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71.
72.
A family is described in which the mother made anti-Rh32 as a result of pregnancy; her second liveborn child had hemolytic disease of the newborn and required an exchange transfusion. In investigating the family, it was found that the father's RN gene did not make rhi and that his second Rh gene made normal amounts of c and e but a reduced amount of f. In the two children of the couple, who inherited a normal r or Ro from their mother, the paternally derived RN encoded an amount of rhi that could be detected in direct typing tests. In the father, lack of production of rhi by RN may have represented a suppressive effect of the ce(f) gene in trans to RN or the presence of an unlinked suppressor of Rh that might also have been responsible for the reduced production of f by his r or Ro gene. The two children in this family are the first persons in whom RN has been shown to make rhi. 相似文献
73.
Activation of Fas antigen, a cell surface receptor molecule, by its ligand results in transduction of a signal for cell death. The Fas system has been implicated in target cell recognition, clonal development of immune effector cells, and termination of the cellular immune response. Fas antigen expression on lymphocytes is regulated by interferon gamma (IFN gamma) and tumor necrosis factor alpha (TNF alpha), cytokines that also have inhibitory effects on hematopoiesis. We investigated Fas antigen expression on human marrow cells and the effects of Fas activation on hematopoiesis in vitro. Freshly isolated immature hematopoietic cells, as defined by the CD34 marker, did not express Fas antigen at levels detectable by fluorescent staining. CD34+ cells, which include progenitors and stem cells, showed low levels of Fas expression in culture, even in the presence of growth factors. Stimulation by TNF alpha and IFN gamma markedly increased Fas antigen expression on CD34+ cells. Anti-Fas antibody, which mimics the action of the putative ligand, enhanced IFN gamma- and TNF alpha-mediated suppression of colony formation by bone marrow (BM) in a dose-dependent manner. This effect did not require the presence of accessory cells. Colony formation from mature (CD34+ CD38+) and immature (CD34+ CD38-) progenitor cells and long-term culture initiating cells were susceptible to the inhibitory action of anti-Fas antibody in the presence of IFN gamma and TNF alpha. Apoptosis assays performed on total BM cells and CD34+ cells showed that anti-Fas antibody induced programmed cell death of CD34+ BM cells.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
74.
Fallopian tumor carcinoma and papillary serous carcinoma of the peritoneum are rare tumors that usually mimic advanced ovarian cancer. The current treatment for these tumors is similar to that for ovarian cancer with approximately an 80% response rate, but only a 20% 5-year survival. Uterine sarcomas are probably the most lethal of the gynecologic malignancies, with frequent recurrence and death despite apparent early diagnosis and aggressive therapy. Gestational trophoblastic tumors, on the other hand, are usually curable, even when widely metastatic disease is present. The clinical features, staging, and current treatment of each of these tumors is reviewed. 相似文献
75.
Prognostic factors associated with recurrence in clinical stage I adenocarcinoma of the endometrium 总被引:7,自引:0,他引:7
J R Lurain B L Rice A W Rademaker L E Poggensee J C Schink D S Miller 《Obstetrics and gynecology》1991,78(1):63-69
Two hundred sixty-four consecutive patients with clinical stage I endometrial adenocarcinoma who underwent primary surgical therapy between July 1979 and August 1988 were followed prospectively and evaluated for disease recurrence for 8-112 months (mean 51.5). Thirty-three patients (12.5%) developed recurrence or died of disease. In univariate statistical analysis, prognostic factors significantly associated with disease recurrence were as follows: age (mean 68.6 years with versus 60.3 years without recurrence; P = .0001); histology (adenocarcinoma 8.8%, adenosquamous 35.7%, papillary 25%, clear-cell 57.1%; P less than .0001); tumor grade (grade 1, 7.7%, grade 2, 10.5%, grade 3, 36.1%; P less than .0001); depth of myometrial invasion (none 9.8%, less than one-half 7.4%, one-half or greater 29.6%; P = .0001); lymph node status (negative 8.3%, positive 47.6%; P less than .0001); non-nodal extrauterine disease spread (absent 11.0%, present 50%; P = .0003); peritoneal cytology (negative 9.4%, positive 26.3%; P = .004), and tumor size (2 cm or less 7%, greater than 2 cm 17.3%; P = .05). Cervical extension and uterine size had no significant effect on recurrence. Using multivariate analysis, grade 3 tumor (P = .002), advancing age (P = .004), lymph node metastasis (P = .006), and presence of extrauterine disease spread other than lymph node metastasis (P = .038) were the only variables significantly associated with disease recurrence or death. This study supports the new International Federation of Gynecology and Obstetrics surgical staging system for endometrial cancer.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
76.
77.
Risk status at discharge and cause of death for postneonatal infant deaths: a total population study
A Kempe PH Wise NS Wampler FS Cole H Wallace C Dickinson H Rinehart DC Lezotte B Beaty 《Pediatrics》1997,99(3):338-344
OBJECTIVES: To obtain population-based, clinical information regarding potentially modifiable factors contributing to death during the postneonatal period (28 to 364 days), we examined all postneonatal infant deaths in four areas of the United States to determine: (1) the cause of death from clinical and autopsy data rather than vital statistics, (2) whether death occurred during initial hospitalization or after discharge, and (3) the portion of postneonatal mortality attributable to infants who left the hospital with identified high-risk medical conditions. DESIGN AND SETTING: Retrospective medical record review of all postneonatal infant deaths with birth weights greater than 500 g (total N = 386) born to mothers residing in: (1) the city of Boston (1984 and 1985, N = 55), (2) the city of St Louis and contiguous areas (1985 and 1986, N = 123), (3) San Diego County (1985, N = 112), and (4) the state of Maine (1984 and 1985, N = 96). Deaths were identified using linked birth and death vital statistics, and medical record audits of infants' and mothers' charts were performed. Causes of death were obtained from medical record review in conjunction with autopsy if performed (72%, N = 278), medical record alone (17%, N = 67), or vital statistics if no other source was available (11%, N = 41). The medical conditions at the time of discharge for each infant were reviewed and, if judged to confer an increased risk of morbidity or mortality, were classified as high risk. RESULTS: The causes of death were sudden infant death syndrome (47%, N = 181), congenital conditions (20%, N = 77), prematurity-related conditions (11%, N = 43), infections (9%, N = 34), external causes (including injuries, drownings, ingestions, and burns) (7%, N = 25), and other (6%, N = 23). In 24% of congenital and 25% to 44% of prematurity-related deaths, infection was the acute or associated cause of death. Infants born to black mothers were more likely than those born to white mothers to die during the postneonatal period of all major causes of death (7.3 per 1000 vs 3.0 per 1000). Overall, 18% (N = 68) of deaths occurred to infants who never left the hospital; 79% (N = 305) of the infants were discharged before death; and discharge status was unknown in 3% (N = 13). Eighty-one percent of all infants with prematurity-related postneonatal deaths were never discharged, and of the total infants who were initially discharged, only 1% (N = 4) subsequently died of prematurity-related causes. Of all postneonatal deaths, only 16% (N = 62) left the hospital with identified high-risk medical conditions. CONCLUSIONS: These findings suggest that the etiology of postneonatal mortality is heterogeneous, with significant complexity in attributing specific causes of death and making designations of "preventability." The vast majority of infants who died of prematurity-related postneonatal causes never left the hospital, and only a small percentage of all infants that left the hospital before death were identified as being at high medical risk. Therefore, strategies for further decreasing postneonatal mortality must link high-risk follow-up programs to more comprehensive strategies that address risk throughout pregnancy and early childhood. 相似文献
78.
79.
NS Tekin† S Ozdolap‡ S Sarikaya‡ E Esturk† S Gumustas‡ 《Journal of the European Academy of Dermatology and Venereology》2007,21(1):25-29
Background Behçet's disease (BD) is a systemic inflammatory disease of unknown aetiology. The pathogenesis of rheumatological findings and the status of bone metabolism in this disease are unknown. Inflammatory diseases may predispose to a decrease in bone mineral density (BMD) and there are many studies concerning osteoporosis in chronic inflammatory diseases. Objective The aim of this study was to investigate BMD and bone turnover markers in patients with BD. Methods Thirty BD patients (17 male and 13 female patients, mean age 36.9 ± 12.6 years) and a total of 30 age‐ and sex‐matched healthy controls (17 male and 13 female controls, mean age 34.9 ± 8.95 years) recruited from the general population were enrolled in the study. Bone mineral density was measured at the lumbar spine (L1‐4) and the left hip (total hip) using dual energy X‐ray absorptiometry. Serum samples were collected between 8 and 10 am after overnight fasting. Serum calcium (Ca), phosphate (P), parathormone (PTH), total alkaline phosphatase (ALP), osteocalcin (OC), erythrocyte sedimentation rate (ESR), and C‐reactive protein (CRP) were measured. Free deoxypyridinoline cross‐links (DPD) in second‐void urine and total daily urinary calcium excretion were analysed. Results No statistically significant difference in lumbar spine or femoral BMD and bone turnover markers were found between BD patients and control groups (P > 0.05). Conclusion Although it is difficult to draw definite conclusions because of the limited number of patients involved, our study indicates that bone mineral density and bone turnover markers in Behçet's disease were no different than in healthy subjects. 相似文献
80.
目的:观察正常人近端肾小管上皮细胞(HK2)是否表达黏附分子CD146,初步探讨CD146与肾小管上皮细胞的关系及其生理意义。方法:实验于2005-05/2006-02在上海交通大学医学院临床检验系实验室完成。①实验材料:人近端肾小管上皮细胞株(HK2,由中国科学院上海生物化学与细胞生物学研究所惠赠)。②实验干预:体外培养的HK2连续观察72h。③实验评估:采用倒置显微镜、光学显微镜下观察肾小管上皮细胞的形态;用反转录-聚合酶链反应方法检测CD146 mRNA的表达;流式细胞仪和免疫荧光法测定CD146蛋白质的表达及其定位;进一步在培养细胞的上清液中检测CD146的可溶性形式(sCD146)。结果:①肾小管上皮细胞的形态学观察和鉴定:传代培养的HK2三四天融合后呈铺路石样铺于培养瓶底,相关抗原检测抗人keratin阳性,抗Ⅷ因子相关抗原阴性。②CD146 mRNA水平的表达:HK2在培养早期(24h)即表达CD146 mRNA(0.092±0.012),但延长细胞的培养时间似乎并没有进一步改变CD146 mRNA的表达水平(0.097±0.005,0.113±0.015,P>0.05)。③CD146蛋白质水平的表达和定位:CD146不仅位于肾小管上皮细胞膜上,而且在细胞核和胞浆中也有表达。体外培养的HK2相互融合时,位于细胞膜上的CD146表达增强,呈线性、持续性地表达于细胞-细胞间的连接部位,同时胞内的CD146标记也相应增强。④细胞上清液中sCD146的检测:HK2上清液中存在CD146的可溶性形式(sCD146)。培养细胞观察24~72h,sCD146水平在48h升高[(18.00±0.80)μg/L],到72h达到高峰[(29.33±1.22)μg/L],与24h[(13.87±0.46)μg/L]比较,差异均有显著性意义(P<0.05)。结论:人近端肾小管上皮细胞组成性地表达CD146,是肾小管上皮细胞新的生物学标志;CD146在细胞内外的表达强度有赖于细胞间联系的建立和细胞增殖的程度,CD146在促进细胞生长和维持组织完整性等方面发挥重要作用。肾小管上皮细胞上清液中存在CD146的可溶性形式,sCD146在一定程度上也反映了细胞的生长和增殖状况。 相似文献