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51.
Mature cystic teratomas of the ovary frequently contain intestinal type epithelium, but they are rarely associated with complete intestinal wall. The association of mature cystic teratoma with mucinous cystadenoma is not unusual. However, the pathogenetic relationship between these two lesions remains unanswered. We report a mature cystic teratoma of the ovary in a 16-yr old female that contained a complete colonic wall in continuity with an endocervical-type mucinous cystadenoma. Both the mucinous cystadenoma and the colonic wall showed the typical histopathological and immunohistochemical patterns of classical mucinous cystadenoma (positive for CK7, negative for CK20) and normal colonic wall (positive for CK20, negative for CK7), respectively. The microscopic and immunohistochemical patterns of the epithelium from the transitional zone between colonic wall-like structure and mucinous cystadenoma demonstrated features of both types of epithelium, positive for both CK7 and CK20, and focally positive for a neuroendocrine marker, chromogranin, which is normally present in colonic mucosa. These results suggest that the mucinous cystadenoma originated from the colonic epithelium of the mature cystic teratoma.  相似文献   
52.
PURPOSE: To identify benchmarks of financial and staff support in internal medicine residency training programs and their correlation with indicators of quality. METHOD: A survey instrument to determine characteristics of support of residency training programs was mailed to each member program of the Association of Program Directors of Internal Medicine. Results were correlated with the three-year running average of the pass rates on the American Board of Internal Medicine certifying examination using bivariate and multivariate analyses. RESULTS: Of 394 surveys, 287 (73%) were completed: 74% of respondents were program directors and 20% were both chair and program director. The mean duration as program director was 7.5 years (median = 5), but it was significantly lower for women than for men (4.9 versus 8.1; p =.001). Respondents spent 62% of their time in educational and administrative duties, 30% in clinical activities, 5% in research, and 2% in other activities. Most chief residents were PGY4s, with 72% receiving compensation additional to base salary. On average, there was one associate program director for every 33 residents, one chief resident for every 27 residents, and one staff person for every 21 residents. Most programs provided trainees with incremental educational stipends, meals while oncall, travel and meeting expenses, and parking. Support from pharmaceutical companies was used for meals, books, and meeting expenses. Almost all programs provided meals for applicants, with 15% providing travel allowances and 37% providing lodging. The programs' board pass rates significantly correlated with the numbers of faculty fulltime equivalents (FTEs), the numbers of resident FTEs per office staff FTEs, and the numbers of categorical and preliminary applications received and ranked by the programs in 1998 and 1999. Regression analyses demonstrated three independent predictors of the programs' board pass rates: number of faculty (a positive predictor), percentage of clinical work performed by the program director (a negative predictor), and financial support from pharmaceutical companies (also a negative predictor). CONCLUSIONS: These results identify benchmarks of financial and staff support provided to internal medicine residency programs. Some of these benchmarks are correlated with board pass rate, an accepted indicator of quality in residency training. Program directors and chairs can use this information to identify areas that may benefit from enhanced financial and administrative support.  相似文献   
53.
Hydrosalpinges adversely affect markers of endometrial receptivity   总被引:22,自引:10,他引:22  
While in-vitro fertilization (IVF) was initially developed in women with tubal factor infertility, recent clinical studies have suggested that the presence of hydrosalpinges lowers implantation and pregnancy rates. We postulated that these hydrosalpinges cause impaired endometrial receptivity. A total of 103 women with hydrosalpinges were prospectively evaluated, and compared with 55 infertile and 44 fertile controls. All women had endometrial biopsies during the window of implantation, analysed by conventional histological criteria, and also stained for three integrin markers of endometrial receptivity (alpha1beta1, alpha4beta1 and alpha vbeta3). Women with hydrosalpinges (cases) expressed significantly less of the alpha vbeta3 integrin compared with controls. There was no difference in expression of alpha1beta1 or alpha4beta1 among groups. A significantly greater number of cases had out of phase histology and missing alpha vbeta3 (type I defects) and absent integrin expression despite normal histological maturation (type II) defects, compared with controls. Of 20 women with impaired endometrial receptivity who were also biopsied after hydrosalpinx surgery, 70% demonstrated increased alpha vbeta3 expression. Seventy-seven percent of type I and 57% of type II defects were corrected postoperatively. Using markers of endometrial receptivity, this study demonstrates that inflammatory hydrosalpinges have an adverse effect on endometrial receptivity, which in some cases may be overcome by surgical treatment of the hydrosalpinx.   相似文献   
54.
Quantification of human immunodeficiency virus type 1 (HIV-1) RNA as a measure of viral load has greatly improved the monitoring of therapies for infected individuals. With the significant reductions in viral load now observed in individuals treated with highly active anti-retroviral therapy (HAART), viral load assays have been adapted to achieve greater sensitivity. Two commercially available ultrasensitive assays, the Bayer Quantiplex HIV-1 bDNA version 3.0 (bDNA 3.0) assay and the Roche Amplicor HIV-1 Monitor Ultrasensitive version 1.5 (Amplicor 1.5) assay, are now being used to monitor HIV-1-infected individuals. Both of these ultrasensitive assays have a reported lower limit of 50 HIV-1 RNA copies/ml and were developed from corresponding older generation assays with lower limits of 400 to 500 copies/ml. However, the comparability of viral load data generated by these ultrasensitive assays and the relative costs of labor, disposables, and biohazardous wastes were not determined in most cases. In this study, we used matched clinical plasma samples to compare the quantification of the newer bDNA 3.0 assay with that of the older bDNA 2.0 assay and to compare the quantification and costs of the bDNA 3.0 assay and the Amplicor 1.5 assay. We found that quantification by the bDNA 3.0 assay was approximately twofold higher than that by the bDNA 2.0 assay and was highly correlated to that by the Amplicor 1.5 assay. Moreover, cost analysis based on labor, disposables, and biohazardous wastes showed significant savings with the bDNA 3.0 assay as compared to the costs of the Amplicor 1.5 assay.  相似文献   
55.
The case of a 40-year-old patient with congenital trisomy 8 and sex chromosome mosaicism is discussed. The main clinical features were: mental retardation, thick and darkly pigmented skin, prominent forehead, convergent strabismus, high arched palate, flexion contractures of the extremities, and numerous skeletal abnormalities. The patient developed severe aplastic anemia followed by an interim period of preleukemia which developed into acute leukemia. Electron microscope examination of the white blood cells at the stage of the aplastic anemia showed ultrastructural abnormalities similar to those observed in other genetic disorders with a predisposition to leukemia, as well as in leukemia.  相似文献   
56.
OBJECTIVE: To evaluate the influence of a brief period of sleep deprivation on cardiac autonomic controls during sleep in healthy infants. DESIGN: Twelve healthy infants with a median age of 8 weeks (range, 7 to 18 weeks) were recorded polygraphically during a morning and an afternoon nap in a sleep laboratory. They were sleep deprived for approximately 2 hours, either in the morning or in the afternoon, before being allowed to fall asleep. Six infants were sleep deprived before the morning nap, and 6 before the afternoon nap. During both naps, their sleep, breathing, and heart-rate characteristics were continuously recorded. Spectral analysis of heart rate was evaluated as a function of sleep stages. Two major peaks were recognizable: a low-frequency component related to sympathetic and parasympathetic activities and a high-frequency component reflecting parasympathetic tonus. The ratio of low-frequency to high-frequency powers was calculated as an index of sympathovagal interaction. RESULTS: When sleep deprived, the infants had an increase in basal heart rate during non-rapid eye movement sleep (P=.021). With sleep deprivation, the ratio of low-frequency to high-frequency powers increased in non-rapid eye movement sleep (P=.005). These findings were consistent with an increase in sympathetic tone. CONCLUSION: Infants exposed to short-term sleep deprivation manifest changes in cardiac autonomic controls during sleep. These findings could be relevant to mechanisms associated with the sudden infant death syndrome.  相似文献   
57.
Summary This study examines the effect of the initial state of hydration on hormone responses to prolonged exercise in the heat. Five subjects at two initial hydration levels (hypohydrated and hyperhydrated) were exposed to a 36°C environment for 3 h of intermittent exercise. During exercise, the subjects were either fluid-deprived, or rehydrated with water or an isotonic electrolyte sucrose solution (ISO). Both the stress hormones, adrenocorticotropic hormone and cortisol, and the main fluid regulatory hormones, aldosterone, renin activity (PRA) and arginine vasopressin (AVP), were measured in blood samples taken every hour. Prior hyperhydration significantly reduced initial AVP, aldosterone and PRA levels. However, except for AVP, which responded to exercise significantly less in previously hyperhydrated subjects (p<0.05), the initial hydration state did not influence the subsequent vascular and hormonal responses when the subjects were fluid-deprived while exercising. Concurrent rehydration, either with water or with ISO, reduced or even abolished the hormonal responses. There were no significant differences according to the initial hydration state, except for PRA responses, which were significantly lower (p<0.01) in previously hyperhydrated subjects who also received water during exercise. These results indicate that prior hydration levels influence only slightly the hormonal responses to prolonged exercise in the heat. Progressive rehydration during exercise, especially when extra electrolytes are given, is more efficient in maintaining plasma volume and osmolarity and in reducing the hormonal responses.  相似文献   
58.

Background  

Genetic polymorphisms of the TCF7L2 gene are strongly associated with large increments in type 2 diabetes risk in different populations worldwide. In this study, we aimed to confirm the effect of the TCF7L2 polymorphism rs7903146 on diabetes risk in a Brazilian population and to assess the use of this genetic marker in improving diabetes risk prediction in the general population.  相似文献   
59.
Bone marrow progenitors migrate to the thymus, where they proliferate and differentiate into immunologically competent T cells. In this report we show that mice transgenic for SV40 T and t antigens under the control of the L-pyruvate kinase promoter develop, in a first step, thymic hyperplasia of both thymocytes and epithelial cells. Morphological studies (histology, immunohistolabeling and electron microscopy) revealed modifications of the thymic microenvironment and gradual expansion of medullary epithelial cells in 1 month-old mice, taking over the cortical region. Then, a thymic carcinoma develops. Two-color labeling of frozen sections identified the transgene in medullary epithelial cells. Flow cytometry analysis demonstrated a marked increase in mature CD4+ and CD8+ thymocytes in adult mice (39 +/- 10 x 10(6) in transgenic mice and 12 +/- 5 x 10(6) in age-matched controls). Furthermore, thymocyte export was disturbed.  相似文献   
60.
BACKGROUND: Pancreatic acinar tissue (PAT) at the gastroesophageal junction (GEJ) has been reported in 3% of adults with Barrett esophagus (BE) and in 24% of healthy subjects. The pathogenesis of this ectopic tissue is controversial. Both an acquired metaplastic process in the setting of BE and a congenital abnormality have been suggested in adults. OBJECTIVE: To clarify the origin of PAT at the GEJ. METHODS: We reviewed material obtained from the GEJ in 69 children and young adults. Each specimen was evaluated by 3 levels stained with hematoxylin-eosin for the presence of PAT, BE, esophagitis, and gastritis. Selected cases were also examined with immunohistochemical stains for lipase, trypsin, and amylase. RESULTS: In 16% of the study population, PAT was present at the GEJ and was not associated with BE. The prevalence of esophagitis and/or gastritis did not vary significantly between patients with and without PAT. CONCLUSIONS: Our data suggest that PAT at the GEJ develops independently of inflammation and is, therefore, likely to be congenital.  相似文献   
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