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21.
Low amplitude pulses of estradiol-17β (E2-17β) are more effective than large single bolus injections or constant exposure to E2-17β in inducing progesterone-facilitated sex behavior in female rats and guinea pigs. The present study examined whether the increased responsiveness to E2-17β is due to an increase in the number of estrogen receptors in the estrogen receptor rich areas of the hypothalamus and amygdala. Initial studies examined the rapid effects (20 min) of a high dose of E2-17β (50 μg) on estrogen receptor immunostaining using either the H222 antibody or the ER 21 antiserum. ER 21 immunostaining was not affected by the E2-17β treatment suggesting that it binds to both occupied and unoccupied estrogen receptors. Therefore the ER 21 antiserum was used to characterize the regulation of estrogen receptor immunoreactivity (ER-IR) by E2-17β. ER-IR was examined for 48 h and serum E2-17β for 24 h following a 2 μg s.c. injection of E2-17β (a dose similar to that used in multiple pulse paradigms). Serum E2-17β peaked 15 to 30 min following the injection and returned to baseline values by 1 h. In all but one area maximal suppression of ER-IR occurred at 12 h. In summary, 1) decreases in estrogen receptor immunoreactivity following E2-17β are consistent with studies in which estrogen receptors were assayed by binding assays and estrogen receptor mRNA was determined by in situ hybridization; 2) the ER 21 antiserum is able to detect both occupied and unoccupied estrogen receptors and 3) H222 immunoreactivity is influenced by the presence of E2-17β, so that the level of H222-IR is a reflection of ligand/receptor binding dynamics. The data suggest that up-regulation of estrogen receptors does not account for the increase in behavioral sensitivity which is observed following multiple pulses of E2-17β.  相似文献   
22.
Pulmonary embolism is a potentially lethal complication among patients with acetabular fractures requiring surgery. The reliability, safety, and extent of efficacy of pharmacologic as well as existing nonpharmacologic anticoagulation prophylaxis in this patient group has not been determined. A careful analysis of the myriad factors acting on these patients who have had major trauma and have undergone a major surgical procedure about the hip prompted a change in our approach to prophylaxis in this patient group. In the period from March 1984 through October 1987, 51 patients having 52 acetabular fractures underwent osteosynthesis at the Wake Forest University Medical Center. Twenty-four patients had two or more identifiable risk factors and underwent insertion of a Greenfield filter for prevention of pulmonary emboli. Filters were inserted at the time of acetabular surgery with C-arm guidance via the internal jugular vein approach. The average time for insertion was 57 min. Placements were verified by plain roentgenograms. There were no complications during filter insertion. Four patients with filters (17%) developed leg edema; in three the edema was minor, and in one the filter trapped what could have been a fatal embolus but caused lower extremity venous stasis severe enough to result in peripheral lower extremity tissue loss. There were no pulmonary emboli (by clinical criteria). The remaining 27 patients had routine medical prophylaxis and no filters. In this group, two patients had a clinically evident pulmonary embolus (7%), and one of these patients died. Two other patients (7%) had minor chronic leg edema. In one of them, a proximal deep venous thrombosis in the lower extremity was documented with venography, requiring rehospitalization and anticoagulant therapy.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
23.
This paper reviews the association of Huntington's Disease (HD) and tic disorder or Tourette Syndrome (TS) We also present the results of a follow-up study of a male with childhood-onset TS and adult-onset HD who died at 45 years of age. The developmental course and results of neuropathologic and molecular studies of this patient are reported. This is the first case of childhood onset of TS with adult onset of HD reported who has come to autopsy. A developmental model for childhood and adult neuropsychiatric disorders is presented.  相似文献   
24.
Background: Cicatricial deformation in child burn of hand often leads to severe squaelae. According to different causes of disease , different plastic surgery were adopted .The key of operation lies in skin repairing , articulation dealing, and thumb correcting, which aim is to resume normal longitudinal and transverse arcs ,holding and clenching ability.  相似文献   
25.
The purpose of this paper is to point out some of the problems that may arise when the conventional genetic model is applied and there are correlated genetic and environmental effects and to indicate a possible solution to the problems raised.  相似文献   
26.
The MMPI was administered to 28 adolescent offspring from marriages in which both parents had taken the test during the ninth grade. Therefore, parent-offspring comparisons could be made on these measures of personality obtained at approximately the same age, one generation apart. Thus age bias is eliminated. Correlations and regressions for the ten clinical scales and K validity scale were determined. Heritability estimates were computed including corrections for parental assortative mating. The heritability estimates for the psychotic scales (6-Pa, 7-Pt, 8-Sc, and 9-Ma) tended to be higher than those for the remaining test scales.This study was supported by NIH grant MH-10679.  相似文献   
27.
交互信息是一种检测系统之间相依性的方法 ,它可以同时检测线性和非线性相关。本文介绍了交互信息的计算方法和性质 ,讨论了它在单个时间序列上的应用 ,并将它应用于心脏状态研究上。利用实验动物的数据 ,我们发现了心搏的运动既不是随机的也不是周期的 ;并且 ,不同心脏状态下的交互信息有很大的差别 ,浅麻 ,机控呼吸和开胸状态下交互信息都相对较小 ,心肌损伤后有明显增大 ,提示心搏的交互信息与心脏健康程度有很大关系  相似文献   
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目的通过对57例妊娠分别使用二维、三维超声测量相关参数估计胎重,并作统计学比较,从而评价三维超声对于估测胎儿体重、诊断胎儿发育迟缓及巨大胎的优势和价值。方法对2005年10月至2006年3月间在我院分娩的57例妊娠,研究组用三维超声测胎儿股容积估计胎重,对照组用二维超声同步测量相关参数估计胎重。结果对两组估重结果与胎儿实际出生体重作相关统计学分析,研究组相关系数为0.983,对照组为0.906(P〈0.05),前者与实际体重关系更密切。结论三维超声测量胎儿股容积估测胎儿体重,较传统二维超声具有更大优势,对于发现胎儿发育迟缓(FGR)及巨大胎意义重大,有利于指导临床冶疗、选择分娩方式。  相似文献   
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