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Vivas-Acevedo Giovanny - - 2010
To evaluate the effect of presence, grade and anatomical side of varicocele on semen parameters and to identify age-related modifications in semen quality in men with varicocele. A prospective clinical study was performed in 363 men with varicocele and 155 normozoospermic men without varicocele. We determined the presence, grade and ...
Xu Jin - - 2010
The determination of paternity of offspring produced by polyandrous females is essential for the understanding of sperm competition mechanisms. The sterile male technique using radiation is one of the most commonly employed methods for this purpose. However, sterilization using radiation is likely to be restricted by the equipment availability and ...
Wilson Ben - - 2010
The stability of couple partnerships is of continual interest to policy makers and many users of official statistics. This research used a sample of adults (from the Office for National Statistics Longitudinal Study) who were in a partnership (married or cohabiting) in the 1991 Census of England and Wales, and ...
Katz Karin - - 2010
This study investigated a potential independent association between hypovitaminosis D and suspected nonalcoholic fatty liver disease (NAFLD) in a nationally representative sample of the US adolescents. Data from 1630 subjects 12-19 years of age were examined using the National Health and Nutrition Examination Survey, 2001-2004. The vitamin D status of subjects ...
Akter Shamima - - 2010
Early cessation of breastfeeding is a cause of significant concern in many developing countries. Premature discontinuation of breastfeeding is known to be associated with avoidable childhood morbidity and mortality as well as high levels of parity and avoidable pregnancies. Using a publicly available demographic dataset from Bangladesh, we applied a ...
Ga??n Natalia - - 2010
The Iberian lynx (Lynx pardinus) is the most endangered felid in the world. Adequate genetic management of in situ and ex situ populations, and linkage between both, require knowledge on male reproductive biology and factors influencing it. We examined the influence of age, free-ranging versus captive conditions and seasonality on ...
Koskas Martin - - 2010
Objective. To study incidence of abnormal hysteroscopic findings according to age. Methods. We retrospectively studied 557 consecutive office hysteroscopies in patients referred for incapacity to conceive lasting at least 1 year or prior to in vitro fertilization. Rates of abnormal findings were reviewed according to age. Results. In 219 cases, ...
Ally Dilara - - 2010
From bacteria to multicellular animals, most organisms exhibit declines in survivorship or reproductive performance with increasing age ("senescence"). Evidence for senescence in clonal plants, however, is scant. During asexual growth, we expect that somatic mutations, which negatively impact sexual fitness, should accumulate and contribute to senescence, especially among long-lived clonal ...
Charlton Benjamin D - - 2010
Although female mammal vocal behaviour is known to advertise fertility, to date, no non-human mammal study has shown that the acoustic structure of female calls varies significantly around their fertile period. Here, we used a combination of hormone measurements and acoustic analyses to determine whether female giant panda chirps have ...
Wiser A - - 2009
The aim of this study was to evaluate the affect of age at the time of orchidopexy on testicular sperm extraction (TESE) results among patients with a history of cryptorchidism and azoospermia. This retrospective study compared TESE results for couples undergoing IVF treatment, among two groups of patients. Group A ...
Canavese F - - 2009
INTRODUCTION: Recent data has indicated the usefulness of performing orchiopexy in the first years of life. In this study, we evaluated testicular function in young men operated on for cryptorchidism in the first year of life. To our knowledge, this is the first report on the effects of such an ...
Beets Gijs - - 2009
Fertility curves sometimes resemble sea waves. During periods that the fertility age patterns change, according to whatever reason, 'this sea' may become very turbulent. Also other sea-like phenomena, for example tsunamis, are discernible in fertility behaviour. This article gives a short overview of the relationships between age of the mother ...
Cardona Maya W??lter - - 2009
Although the effect of maternal age on fertility is well known, it is unclear whether paternal age also affects fertility. The aim of this retrospective study was to establish an association between the age of the individuals from Medellin, Colombia with semen volume, rapid progressive motility (a), total progressive motility ...
Au Phil Chi Khang - - 2010
Induced ovulation maximizes captive breeding success, increasing productivity and facilitating the contribution of otherwise infertile animals to the genetic pool. In marsupials, induced ovulation to produce fertile young is unknown. Here we present an induction protocol efficient in inducing non-cycling and non-reproductive females to cycle, mate, ovulate, and conceive. Ovulation ...
Serour Gamal - - 2010
OBJECTIVE: To estimate the live-birth and miscarriage rates in 1-year age increments for women aged ≥40 years undergoing in vitro fertilization or intracytoplasmic sperm injection (ICSI-IVF) with autologous oocytes. DESIGN: Retrospective database and chart analysis. SETTING: Egyptian IVF and embryo transfer center. PATIENT(S): One thousand six hundred forty-five women aged ...
Kumar Davendra - - 2010
A study was conducted to evaluate the semen production and sperm motion characteristics of ram lambs by computer-aided semen analysis technique. Eight Malpura rams were raised under intensive management system and were trained for semen collection at a weekly interval from the age of 6 months. Rams were scheduled for ...
Rako L - - 2009
In insects including Drosophila melanogaster, females can overwinter at the adult stage by adopting a shallow reproductive diapause, but almost nothing is known about male reproductive diapause. In this study, we test for the maintenance of fertility in overwintering males from the eastern Australian D. melanogaster cline. Males from southern ...
La Vignera S - - 2009
Cryptorchidism is the most frequent defect of the male urogenital tract at birth. It represents a risk factor for primitive testiculopathy associated with long-term complications (infertility, testicular neoplasia, and hormonal changes). An only consensus exists: "children with bilateral cryptorchidism who are not treated in early age are certainly set to ...
Eltigani Eltigani E - - 2009
Egypt and Tunisia began their fertility transition at almost identical fertility levels and at roughly the same time period, yet the difference in the pace of decline has been such that the total fertility rate (TFR) in Tunisia reached replacement level by the year 2001, whereas the TFR in Egypt ...
Gögele Martin - - 2009
Stelvio, Martello and Curon, three villages of the Venosta Valley, South Tyrol (Italy), were recently included in a large genetic survey because of their isolation. This study focuses on the long-term reproductive behaviour of these villages. Family size, age at marriage and marital fertility were estimated based on a genealogy ...
Goff K - - 2009
To determine whether sperm derived from the vas deferens could be retrieved and successfully cryopreserved, testes were collected from 20 rhesus macaques (Macaca mulatta). The males ranged in age from 3 to 19 yr with an average age of 8.5 yr. No sperm was obtained from three animals that were ...
Wedell Nina - - 2009
Sexual conflict can promote rapid evolution of male and female reproductive traits. Males of many polyandrous butterflies transfer nutrients at mating that enhances female fecundity, but generates sexual conflict over female remating due to sperm competition. Butterflies produce both normal fertilizing sperm and large numbers of non-fertile sperm. In the ...
Cornwallis Charlie K - - 2009
An important predictor of male fitness is the fertilizing efficiency of their ejaculates. Ejaculates are costly to produce and males are predicted to devote greater resources to copulations with reproductively superior females. It is well established that males allocate different numbers of sperm to ejaculates. However, less is known about ...
Schneider M I - - 2009
Few ecotoxicological studies have used life table analysis to evaluate the toxicity of pesticides on beneficial organisms. This study is the first report of the effect of the herbicide glyphosate on a predator insect, Chrysoperla externa, using a demographic approach. This predator is associated to soybean pests and has a ...
Shenk Mary K - - 2009
Over the last three decades many authors have addressed the demographic transition from the perspective of evolutionary theory. Some authors have emphasized parental investment factors such as the costs of raising children, others have emphasized the effects of mortality and other forms of risk, and others have emphasized the biased ...
Hawkes Kristen - - 2009
A grandmother hypothesis may explain why humans evolved greater longevity while continuing to end female fertility at about the same age as do the other great apes. With that grandmother hypothesis in mind, we sought to compare age-specific mortality and fertility rates between humans and chimpanzees, our closest living relatives, ...
Chotirmall S H - - 2009
Infertility rates among males with cystic fibrosis (CF) approximate 97%. No information is currently available within Ireland determining an understanding of fertility issues and the best methods of information provision to this specialized group. This study aimed to determine understanding and preferred approaches to information provision on fertility issues to ...
Crawshaw M A - - 2009
Discussion and management of potential reproductive health sequelae of adolescent cancer are essential and challenging components of care for the multidisciplinary team. Despite this, research has been limited to specific experiences (e.g. sperm banking) or fertility-related concerns of adult survivors. This grounded theory study of 38 male and female survivors ...
Gagnon Alain - - 2009
Frontier populations provide exceptional opportunities to test the hypothesis of a trade-off between fertility and longevity. In such populations, mechanisms favoring reproduction usually find fertile ground, and if these mechanisms reduce longevity, demographers should observe higher postreproductive mortality among highly fertile women. We test this hypothesis using complete female reproductive ...
Vahidi Serajeldin - - 2009
This study aimed to determine the prevalence of lifetime and current primary infertility in Iran. The study was conducted in 2004-5 in all the 28 provinces of Iran. A cluster sampling method was used to select 10 783 women aged 19 to 49 years for the survey. Lifetime primary infertility ...
Baéza E - - 2009
The aim of this study was to determine the specific characteristics of carcass and meat from an old French chicken breed, the 'Géline de Touraine' (GT), characterised by a very slow-growing rate and usually slaughtered at 120 days of age. For this purpose, we compared the GT with an experimental ...
Billingsley Sunnee - - 2010
Fertility has unanimously declined across the entire post-communist region. This study explores the variation in fertility trends over time among these countries and assesses to what degree three explanations are applicable: second demographic transition (SDT), postponement transition (PPT) or reaction to the economic crisis. Moreover, on the basis of SDT ...
Ssebuliba, R N
There are 84 distinct cultivars of highland bananas (Musa   spp.) in Uganda, grouped in five clone sets and it is not known which among these are female fertile. The objective of the study reported herein was to identify female fertile highland bananas that can be used in a cross ...
Trsinar Bojan - - 2009
OBJECTIVES: The aim of the study was to compare fertility potential in patients who had been operated upon in childhood because of unilateral or bilateral cryptorchidism. METHODS: The study covered 68 men (age 25-30 years) with a history of unilateral (49) or bilateral orchidopexy (Mandat et al. in Eur J ...
Stradaioli G - - 2009
Phospholipid hydroperoxide glutathione peroxidase (PHGPx) is a selenoperoxidase accounting for most of the selenium content in mammalian testis, which has been found to be linked to fertility in humans. In this study, we addressed the issue whether PHGPx content in spermatozoa could be a predictive index of fertilization capacity for ...
Cremin I - - 2009
OBJECTIVE: To identify reporting biases and to determine the influence of inconsistent reporting on observed trends in the timing of age at first sex and age at marriage. METHODS: Longitudinal data from three rounds of a population-based cohort in eastern Zimbabwe were analysed. Reports of age at first sex and ...
Mukhopadhyay Dyutiman - - 2010
OBJECTIVE: To compare the semen quality and age-specific changes in men between the 1980s and 2000s. DESIGN: Prospective study. SETTING: Andrology laboratory, University of Calcutta, India. PATIENT(S): A semen sample was obtained from 3729 men presenting for infertility problems in two distinct decades, that is, between 1981-85 and 2000-2006. INTERVENTION(S): ...
Evans Jonathan P - - 2009
Sperm competition theory predicts that males should tailor their investment in ejaculates according to the number of rival males competing to fertilize a female's eggs. Research spanning several taxa supports this prediction by showing that males are often sensitive to the level of sperm competition and adjust their investment in ...
Bretherick Karla L - - 2010
OBJECTIVE: Female fertility declines with age; however, women are increasingly delaying childbearing until later in their reproductive years. One of the factors that may contribute to this trend is a general lack of knowledge about the decline in fertility with age. DESIGN: Self-report survey. Questions pertained to participant demographics and ...
Resler J H - - 2009
The spermatozoa of ticks are anomalous in many respects: they are very large, cytoplasm-rich cells which lack a flagellum but move with a peculiar gliding motility. Their metamorphosis after deposition in the female has been well documented, but many of the subsequent events in the career of the spermatozoa are ...
Akande A A - - 2009
BACKGROUND: Biochemical laboratory investigations potentially contribute to the diagnosis of over 50-75% of couples being investigated for infertility. Both hormonal and anti-hormonal treatments have achieved great successes in the treatment of infertility. Our aim therefore was to investigate the pattern of biochemical abnormalities in females diagnosed as infertile form anovulation. ...
Oborna Ivana - - 2009
AIMS: Excessive production of reactive oxygen species (ROS) in semen has been linked to male infertility. Main sources of ROS in male genital tract are immature and/or damaged spermatozoa and a subpopulation of leukocytes known as polymorphonuclear neutrophils (PMN). METHODS: Study group included male partners of infertile couples, 67 normospermic ...
Ugwuja, EI; ;
In order to provide an insight to the prevalence of low sperm count and abnormal semen parameters in suspected subfertile/ infertile men in our environment, semen samples collected from one hundred and seventy (170) men aged 21-50 years, whose wives were seen at a private fertility clinic in Abakaliki, Nigeria ...
Machado G M - - 2009
The objective was to evaluate the effect of Percoll volume, and duration and force of centrifugation on sperm quality characteristics, embryo development, and sex ratio of in vitro-produced (IVP) bovine embryos. Frozen-thawed semen from four bulls were submitted to three Percoll procedures: T1-4 mL of Percoll, centrifuged for 20 min ...
Xia Yankai - - 2009
BACKGROUND: Limited studies have suggested that male reproductive function might be associated with exposure to polycyclic aromatic hydrocarbons (PAHs). METHODS: Five hundred and thirteen idiopathic infertile male subjects and 273 fertile males as controls were recruited in this study, through eligibility screening procedures. Individual exposures to PAHs were measured as ...
Feki N Chakroun - - 2009
Concerns about the worldwide decline in semen quality over the past 50 years are increasing. Western countries have shown a decline in semen quality. However, in non-Western countries studies are sparse. We investigated trends in semen parameters between 1996 and 2007 in the Sfax area of southern Tunisia in a ...
Wolf J - - 2009
The objective of this study was to investigate individual fixed effects in an animal model for breeding value estimation for semen traits of pig sire breeds. Data (151,755 ejaculates collected from 2000 through 2007 from 2,077 Duroc, sire line of Large White, Piétrain, and single cross boars between these breeds) ...
Maalouf W E - - 2009
The objectives of these studies were to determine the effects of cumulus cell removal and caffeine treatment on the development of in vitro matured ovine oocytes aged in vitro until until fertilization. Oocytes were denuded (DO) at 24h post-onset of maturation (hpm), control cumulus oocyte complexes (COC's) and DO groups ...
Schmidt Jonathan A - - 2009
Reproductive aging of the male is characterized by decreasing fertility; however, factors that protect against reproductive aging in the male are largely unknown. Previous work has demonstrated that both female presence and aging have a dramatic effect on fertility in the male; yet, the effect of female presence on fertility ...
Wade Michael J - - 2009
Many essential organelles and endosymbionts exhibit a strict matrilineal pattern of inheritance. The absence of paternal transmission of such extranuclear components is thought to preclude a response to selection on their effects on male viability and fertility. We overturn this dogma by showing that two mechanisms, inbreeding and kin selection, ...
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