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21.
Na AF Harnaen EJ Farmer PJ Sourial M Southwell BR Hutson JM 《Journal of pediatric surgery》2007,42(9):1566-1573
Aim/Background
How the gubernaculum guides the testis into the scrotum remains controversial, with various proposals from passive inversion to active growth. We aimed to determine if the gubernaculum contains an area of active proliferation, such as a “progress zone” in a growing embryonic limb bud, using a fluorescent cell membrane marker, 1,1′-didodecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate [DiIC12(3)], to trace cell migration, and 5-bromodeoxyuridine (BUDR) (a thymidine analogue) as a mitotic marker.Methods
Gubernacula were collected from neonatal male rats (n = 42, day 1-2, Sprague-Dawley) and cultured with calcitonin gene-related peptide (CGRP; 714 nmol/L). 1,1′-didodecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate-coated glass beads (diameter, 150-212 μm) were placed next to the bulb for the first 3 hours. Gubernacula were cultured for 3, 18, and 24 hours, then frozen sections cut and examined by confocal microscopy (wavelength, 549 nm). In a second experiment, pups not exposed to exogenous CGRP (n = 53, day 0, Sprague-Dawley) were injected intraperitoneally with BUDR (50 mg/kg of body weight); gubernacula were collected at 2, 48, 72, and 96 hours postinjection (PI), sectioned, and stained using immunohistochemistry to count the number of BUDR-positive cells per 100 cells (labeling index) in the bulb, cremaster, cord, and epididymis.Results
After 24 hours' culture with CGRP, the bulb showed an oval region (diameter, 300 μm) of high fluorescence, and the cremaster region showed elongated cells migrating out of the bulb. When cultured without CGRP, the same oval region contained no fluorescence. In vivo BUDR labeling index increased in all areas until 48 hours postinjection and then decreased most rapidly in the bulb (P < .05), in the presence of endogenous CGRP from the genitofemoral nerve.Conclusions
The rat gubernaculum contains a putative progress zone, such as in a growing limb bud, in the presence of CGRP. Cells migrate out of this zone to form cremaster muscle. We hypothesize that proliferation in the bulb elongates the gubernaculum, whereas proliferation of cremaster cells would increase gubernacular diameter. This brings to “life” the gubernaculum as an actively growing organ in contrast to the inert ligament connecting the testis to the scrotum portrayed in most anatomy textbooks. 相似文献22.
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OBJECTIVE: Accurate information regarding the psychopathological consequences of surviving traumatic injury is of great importance for effective health service design and planning. Regrettably, existing studies vary dramatically in reported prevalence rates of psychopathology within this population. The aim of this study was to identify the prevalence of psychiatric morbidity following severe injury by adopting a longitudinal design with close attention to optimizing the research methodology. METHOD: Consecutive admissions (N=363) to a level 1 trauma service, excluding those with moderate or severe traumatic brain injury, were assessed at three time periods: just before discharge and 3 and 12 months after their injury. Structured clinical interviews were used to assess anxiety disorders, depressive disorders, and substance use disorders. RESULTS: Posttraumatic stress disorder (PTSD) and major depressive disorder were the most frequent diagnoses at both 3 and 12 months, with 10% of participants meeting diagnostic criteria for each disorder at 12 months. Over 20% of the group met criteria for at least one psychiatric diagnosis 12 months after their injury. Comorbidity was common, with the most frequent being PTSD with major depressive disorder. CONCLUSIONS: Psychopathology following injury is a frequent and persistent occurrence. Despite the adoption of a rigorous and potentially conservative methodology, one-fifth of participants met criteria for one or more psychiatric diagnoses 12 months after their injury. These findings have major implications for injury health care providers. 相似文献
25.
Mond JM Rodgers B Hay PJ Owen C Beumont PJ 《The International journal of eating disorders》2004,36(1):89-98
OBJECTIVE: To investigate nonresponse bias in a two-phase epidemiologic study of eating-disordered behavior. METHOD: Self-report questionnaires were delivered to a community sample of women aged 18-45 drawn from the electoral roll. Follow-up interviews were completed with a subgroup of respondents. Eating disorder psychopathology, general physical and mental health, and sociodemographic characteristics were compared among early (n = 259) and late (n = 71) respondents at the first phase of the study and among individuals with whom interviews were completed (n = 208) and individuals declining to be interviewed (n = 63) at the second phase. RESULTS: With respect to levels of eating disorder psychopathology, and on all other measures, individuals who responded at the first phase of the study only after repeated reminders did not differ from those who responded to the initial mailout, and individuals who declined to be interviewed did not differ from individuals with whom interviews were completed. CONCLUSIONS: Nonresponse bias among individuals declining to be interviewed is unlikely to pose a problem in two-phase epidemiologic studies of eating disorders. Further research is needed to examine the characteristics of nonrespondents at the first phase of such studies. 相似文献
26.
OBJECTIVES: Maternal serum alpha-fetoprotein (AFP) levels have been known to be increased in red blood cell alloimmunisation. Since AFP is now thought be a pro-erythropoietic factor, we wished to evaluate fetal serum levels of AFP in cases of alloimmunised pregnancies. METHODS: We studied AFP levels in 32 fetal serum samples from women with red blood cell alloimmunisation at the time of the first fetal blood sampling. We expressed the levels of AFP and haemoglobin as absolute numbers and as delta values (number of SDs by which the observed value differed from the normal mean for the same gestation). Main outcome measures were fetal serum AFP levels and fetal haemoglobin concentration. RESULTS: Overall, fetal AFP level was higher than normal in the cases (delta values 2.4 +/- 5.5 SD). However, mildly affected non-hydropic cases had higher levels than severely affected fetuses with hydrops. CONCLUSIONS: Fetuses affected by red blood cell alloimmunisation have increased levels of serum AFP but these levels fall back to low levels in severe anaemia especially with hydrops, which could represent the failing of a compensatory erythropoietic mechanism. Our results suggest that fetal haematopoiesis is activated early in red blood cell alloimmunisation but was subsequently impaired. 相似文献
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Hay P Katsikitis M Begg J Da Costa J Blumenfeld N 《Psychiatric services (Washington, D.C.)》2003,54(7):1028-1030
A six-month cohort of general adult psychiatric inpatients was followed for up to two years to evaluate outcome and contrast the validity of DSM-IV measures of adaptive functioning-the Global Assessment of Functioning (GAF), the Social and Occupational Functioning Assessment Scale (SOFAS), and the Global Assessment of Relational Functioning Scale (GARF). Detailed data, including quality-of-life ratings and DSM-IV axis I and V codes, were collected by interview and self-report questionnaires for 53 study participants. Patients' retrospective ratings of the care they received were not predictive of outcome. Adaptive functioning at discharge was predictive of both severity of illness and social functioning at follow-up. The SOFAS had the strongest concurrent and predictive validity, the latter both for length of initial inpatient stay and two-year outcome. 相似文献
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