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1.

Background

Testicular cancer (TC) represents 1% of all new male cancer cases but remains the most frequent cancer in adolescents and young adults in industrialized countries. In this study, we assessed time trends in use of sperm cryopreservation by men with TC from 1990 to 2013 in France.

Methods

We collected data from patients diagnosed with TC who underwent sperm cryopreservation in the French national network of sperm banks. Trends in the incidence of sperm cryopreservation were estimated through two statistical models: the commonly used Poisson regression model and the Verhulst model.

Results

Between 1990 and 2013, the overall incidence of sperm cryopreservation rose from 1.73 to 5.57 per 100,000 person-years. Poisson regression predicted an incidence of 9 per 100,000 [95% CI?=?8.66–9.34] in 2020. However, since 2005, the observed sperm cryopreservation rate seems to be attenuating. The Verhulst model predicted an incidence of 6 per 100,000 after 2020.

Conclusions

Limitations include the impossibility of analyzing age-standardized incidence. Based on the Verhulst model, results suggest that it is still relevant to follow up TC incidence and sperm cryopreservation in order to confirm or refute the potential decrease already observed in this disease.
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2.
We conducted a phylogeographic analysis of the strictly aquatic and critically endangered Central American river turtle, Dermatemys mawii, as part of a conservation management program for the species. We sampled 238 individuals from 15 different localities throughout the species range. Using sequence fragments from the mtDNA Cyt b and ND4 genes, we identified 16 different haplotypes. Overall, our results reveal a signal of phylogeographic structure throughout the range, which appears to have been secondarily blurred by extensive gene flow. Notably, this also applies to genetic structuring across three major hydrological basins that pose biogeographic breaks in other aquatic taxa. Divergence times of mtDNA haplotypes in D. mawii suggest that the main lineages split in the Pliocene–Pleistocene (3.73–0.227 MA) and demographic tests indicate that the species has undergone drastic demographic size fluctuations since this time period. One ancient haplotype (1D) was found to exhibit sequence divergence of up to 2% from other haplogroups. Divergence of this magnitude is indicative of species level differentiation in other turtle genera. Haplotype 1D was found in only two localities, Sarstun and Salinas, but specimens with other haplotypes were also found in those localities. It is not known whether the individuals with the 1D haplotype interbreed with non-1D individuals. Our results suggest that human activity, such as harvesting and long distance transport of animals, may have influenced the current patterns of genetic diversity. For more than 2000 years, D. mawii has been consumed by people from Middle American cultures, and the archeological record contains strong evidence that the Mayans transported animals between villages and far away from their natural distribution range. Therefore, the large-scale pattern of haplotype sharing even across hydrological barriers, the observed low haplotype diversity in some populations and the contemporary absence of a pronounced phylogeographic pattern is likely due to a combination of population expansions, gene flow, extensive human-mediated-movements and recent bottlenecks resulting from over-harvesting.  相似文献   

3.
Following the 1991 Gulf War, a number of soldiers who fought there began to complain of various symptoms and disorders, the collection of which came to be known as Gulf War syndrome (GWS). A debate has raged about the nature and cause of this illness, with many suggesting that it is a psychiatric condition. GWS continues to be a contested illness, yet there is no disputing that many Gulf veterans are ill. This article considers the way in which GWS sufferers understand their illness to be physical in nature and the way in which they negotiate and resist psychological theories of their illness. Based on 14 months of ethnographic fieldwork in the United Kingdom, data for this article were collected mainly by in-depth, semistructured interviews with GWS sufferers, their family members, doctors, and scientists, as well as healthy Gulf veterans. A total of 93 informants were interviewed, including 67 UK Gulf veterans, most of whom were ill. The paper argues that despite the increasing presence of psychiatry in military discourse, GWS reveals the way that people are able to transform, negotiate and even negate its power and assumptions.  相似文献   

4.
Aggression among wild spider monkeys is most frequently reported to occur between the sexes, with adult males directing aggression towards adult females and the aggression is normally non-injurious. After two severe instances of aggression in the group of spider monkeys housed at Chester Zoo, we developed a questionnaire to investigate the frequency, direction and possible reasons for aggression in zoo-housed spider monkeys. We sent our questionnaire to 55 zoos worldwide and obtained records from 26 groups, which yielded detailed accounts of 143 aggressive incidents: 56 events for the actors and 127 events for the targets of aggression. We found that zoo-housed spider monkeys are predominantly maintained in small social groups, with a single adult male, two adult females and their offspring. Of the aggression reported, 23.1% of incidents resulted in severe or lethal injuries. Adult males were the most frequent actors of aggression and accounted for 66.7% of incidents. Six cases of male–male aggression were lethal. The most striking pattern was that adult males directed aggression towards non-adult males more than any other age/sex category. The most frequently reported context of aggression was tension between adult and non-adult males. These findings contradict previous reports from wild spider monkeys where female-directed male aggression is most frequently reported. In light of our findings, we recommend that males form the core of the group and that females be relocated among groups to reflect the wild condition of male philopatry and female dispersal. In addition, enclosure design should allow opportunities for the monkeys to segregate themselves from other group members, simulating fission, which is a conflict management strategy for avoiding aggression in wild spider monkeys.  相似文献   

5.
The most controversial fishery in U.S. waters of the Gulf of Mexico (Gulf) is for northern red snapper Lutjanus campechanus, which collapsed in the late 1980s when stock biomass became too low to be fished commercially in the eastern Gulf. Red snapper management began in 1989; the stock is now showing signs of recovery. The Gulf of Mexico Fishery Management Council has been slow to sufficiently reduce catches of the directed fisheries to rebuild the stock in a timely fashion, although compliance with the Magnuson-Stevens Reauthorization Act of 2006 (MSRA) required substantial cuts in the harvest of red snapper beginning in 2007. In our opinion, this could have been avoided if conservative management practices had been adopted earlier. We believe that ‘faith-based fisheries’ arguments have been used to defer effective management of red snapper in the Gulf, which in turn has strained the relationship between science, management, and stakeholders there. We provide a simple empirical argument and alternate interpretations of a recently published perspective on the historical fishery of red snapper in the Gulf to conclude that the preponderance of evidence used in the agency stock assessment process, and the simple arguments made here, do not support the perspective that the red snapper stock has increased in size sufficiently to defer compliance with the MSRA.  相似文献   

6.
Abstract

The aim of this special issue is to map the extent of generational change among Britain's ethnic minority population and to understand some of the underlying processes involved. Is there greater integration across generations, or has the ‘new second generation’ in Britain remained isolated from the mainstream, perhaps as a result of the prejudice and discrimination from the white British that they have encountered or because of desires to maintain ethnic values and resist western practices? We also ask whether processes of generational change have proceeded at the same pace and direction in different domains – notably cultural, social, structural and political – and whether it has proceeded at the same pace among different minorities.  相似文献   

7.
Natural levels of infertility in many taxa are often remarkably high, amounting to a considerable fitness cost which one expects to be minimized by natural selection. Several mechanisms have been proposed as potential causes of infertility, including inbreeding depression, genetic incompatibilities and selfish genetic elements. Infertility may also be an inherent result of conflict over fertilization between the sexes in polyandrous species, either because too many sperm enter the egg or because of over‐efficient barriers to such polyspermic fertilizations. We generated phylogenetic independent contrasts to examine the variation in hatching success for a maximum of 58 species of birds in relation to two measures of female polyandry. Hatching success varied enormously across species (range: 61–100%), with a mean of 12% of eggs failing to hatch, but was not related to either the rate of extrapair paternity or to relative testes size. Thus, the causes of this significant fitness cost remains unclear and merits further examination by evolutionary biologists.  相似文献   

8.
Testate amoeba (TA) assemblages were collected in 2005 from four ponds in Komo?any (Prague, Czech Republic). An analysis of seasonal taxonomic variability of TA populations and its correlation with the limnological characteristics of the area (temperature, pH, total organic carbon, nitrogen, phosphorus, heavy metals, etc.) was performed. The predominant genera were Difflugia, Arcella, and Centropyxis. The most significant changes in the TA community occurred between March and July. Arcella genus dominated in March and April; in May, Arcella and Centropyxis genera were present in the same amount; in June, Arcella genus disappeared, and Difflugia genus started to dominate the community. A multivariate redundancy analysis showed statistically significant correlations between the environmental parameters and the composition of the TA community. The results indicate a negative correlation between TA quantities and Ni, Cd, PAH, Mn, As, and Pb. TA were also affected by concentrations of NH4(+), NO3(-), and P, as well as by temperature variations. The observed correlations between the species composition and environmental parameters can be used in paleoecological interpretations of fossil TA communities. Our results also prove the suitability of TA as water quality indicators in urban areas.  相似文献   

9.
Tuberculosis (TB) is an infectious disease that continues to take its toll on human lives. Paleopathological research indicates that it has been a significant cause of death among humans for at least five thousand years. Because of the devastating consequences to human health, social systems, and endangered primate species, TB has been the subject of many and varied research efforts throughout the world, efforts that are amassing an enormous amount of data concerning the causative agent Mycobacterium tuberculosis. Despite sequencing of the M. tuberculosis genome and numerous molecular epidemiological studies, many questions remain regarding the origin, evolution, and future co-evolutionary trajectory of M. tuberculosis and humans. Indeed, the origin of pre-Columbian New World TB has been and remains hotly debated, and resolution of this controversy will likely only come with integration of data and theory from multiple disciplines. In this paper, we discuss the pre-Columbian TB controversy, and then use research from biological and biomedical sciences to help inform paleopathological and archaeological studies of this ubiquitous disease that plagued our ancient forbears.  相似文献   

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Bycatch of unwanted, prohibited, or protected species is a problem in most commercial fisheries. Trawl fisheries are particularly prone to bycatch problems because trawls are not species-selective. In this paper, I review the history of finfish bycatch research in the Gulf of Mexico shrimp trawl fishery and explore the use of quotas to reduce finfish bycatch by examining four fisheries that currently use bycatch quotas: (1) the arrow squid trawl fishery of New Zealand, which uses fleet bycatch quotas for sea lion bycatch, (2) the Alaskan groundfish trawl fisheries, which use fleet quotas under a vessel incentive program for prohibited species, (3) the groundfish trawl fishery of British Columbia, Canada which uses individual vessel bycatch quotas for prohibited species, and (4) the multi-species trawl fisheries of New Zealand, which use catch balancing, or individual transferable quotas, for most commercially landed species. Based on the bycatch quota experiences in these fisheries, elements of successful bycatch quota programs include: (1) individual accountability, in the form of individual or cooperative bycatch quotas, rather than fleet quotas, (2) 100% observer coverage, (3) relatively small, manageable fleets, (4) limited landing ports that can be easily monitored, particularly if observer coverage is incomplete, (5) reliable enforcement, (6) penalties that are true disincentives, and (7) some flexibility in the system for fishermen to have alternatives to manage their bycatch. The Gulf of Mexico shrimp trawl fishery, with an estimated 20,000 licensed boats, is currently too large for individual bycatch quotas to be practical, although individual or cooperative bycatch quotas would be excellent strategies for reducing the bycatch of a smaller fleet. Mobile closed areas might be beneficial for reducing the bycatch of particular species, but these short-term closures would require real-time monitoring of bycatch rates and vessel monitoring systems on all vessels. However, under any management regime, incentives and/or rigorously enforced disincentives are the key to successful bycatch reduction.  相似文献   

13.
Cloning efficiency has not been dramatically improved after the first success of somatic cell nuclear transfer (SCNT) in sheep in 1997. The reasons for the low efficiency of SCNT embryos must be attributed to the insufficient reprogramming of the donor nucleus in ooplasm. It has been clarified that the methylation and acetylation status are disordered in SCNT embryos and the gene expression pattern is different and widely varied in SCNT embryos, compared with fertilized embryos. In this paper, we focused on the role of the donor nuclei in cloning efficiency, and discuss whether ooplasm can reprogram any nucleus.  相似文献   

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15.
Acanthamoeba hosts diverse microbial organisms including viruses, bacteria, yeast and protists, some of which are potential human pathogens. The precise nature of this symbiosis is not clear, but it is suggested that such interactions enable pathogenic microbes to survive hostile conditions and lead to their transmission to susceptible hosts to establish infection. In particular, Acanthamoeba-bacteria interactions have gained significant attention by the scientific and the medical community and have led to speculations of employing anti-amoebic approaches in eradicating 'superbugs' from clinical settings. Here, we discuss the nature of these convoluted interactions and the benefit they represent for the symbionts.  相似文献   

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BACKGROUND: Müllerian adenosarcoma is a rare morphologic variant of uterine sarcoma that, although well described histologically, is scarcely mentioned in the cytologic literature. CASE: A 75-year-old female was suspected of having atypical endometrial hyperplasia on an endometrial smear. However, subsequent imaging techniques revealed the presence of a bulky, polypoid mass filling the uterine cavity. On pathologic examination of the hysterectomy specimen, the polypoid tumor was diagnosed as mullerian adenosarcoma, homologous, with sarcomatous overgrowth, in which the sarcomatous component was compatible with high grade endometrial stromal sarcoma. Imprint smears of the tumor consisted of two morphologic patterns, sarcomatous and glandular. The sarcomatous tumor cells, with coarse chromatin and relatively scant cytoplasm, formed small aggregates or appeared alone. These cells were semiround or oval and had conspicuous nucleoli. In addition to these observations, small and large clusters of glandular cells with mild atypism were interspersed with the sarcomatous cells. CONCLUSION: Cytologic examination of müllerian adenosarcoma well reflects its pathologic features.  相似文献   

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A. Talaat, D. Brinkmann, J. Dhundee, Y. Hana, J. Bevan, R. Irvine, S. Bailey and R. Woolas
Risk of significant gynaecological pathology in women with ?glandular neoplasia on cervical cytology Objective: To review the risk of pre‐invasive and invasive gynaecological pathology in women referred with cervical cytology reporting ?glandular neoplasia. Methods: Review of the case notes of all women referred with cervical cytology reported as ?glandular neoplasia between January 1999 and December 2008 at two UK hospitals: Portsmouth Hospitals NHS Trust and Queen Mary’s Hospital Sidcup. The category of ‘borderline nuclear change in endocervical cells’, result code 8 according to the national health service cancer screening programme (NHSCSP), was excluded from the study. Results: A total of 200 women were identified using the hospitals’ pathology computer systems. Invasive carcinoma was found in 48 women (24%): 28 endocervical adenocarcinomas, eight squamous cell carcinomas (SCC), ten endometrial and two ovarian adenocarcinomas. Pre‐invasive neoplasia was found in 115 (57.5%), including 14 cervical glandular intraepithelial neoplasia (CGIN), 31 cervical intraepithelial neoplasia (CIN) grade 2/3 and 70 concomitant CGIN and CIN2/3. CIN1/HPV was found in 25, simple endometrial hyperplasia in three and no histological abnormality in three. Thirty‐four (70.8%) of 48 invasive carcinomas (of which 23 were endocervical adenocarcinomas) were in asymptomatic women investigated for abnormal cytology. Fourteen of 34 (41.4%) of those with ?glandular neoplasia thought to be endometrial were CGIN or CIN2/3. Colposcopic appearances were normal in 47.6% of women with pure cervical glandular neoplasia (adenocarcinoma or CGIN) compared with 12.8% with squamous cell lesions (CIN2/3 or SCC): P = 0.0001. Thus, colposcopy was more sensitive for detecting squamous cell abnormalities than their glandular counterparts. Although cervical adenocarcinomas are less amenable to prevention by screening than cervical SCC, in our study cervical cytology predominantly detected these abnormalities at their early asymptomatic stages. Conclusion: At least CIN2 was found in 81.5% in women referred with cervical cytology reporting ?glandular neoplasia. A thorough evaluation of the whole genital tract is needed if colposcopy is negative.  相似文献   

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