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31.
应用体视学方法对卵巢浆液性肿瘤进行研究,从定量的角度对卵巢良性、交界性及恶性肿瘤的五项指标进行比较,包括(1)细胞核长短轴之比;(2)结缔组织间质与上皮细胞体积密度之比;(3)细胞核与细胞浆体积密度之比(核浆比);(4)细胞核平均直径;(5)乳头的上皮厚度。结果表明恶性肿瘤核浆体积密度比明显高于交界性及良性肿瘤(p<0.01);恶性肿瘤结缔组织间质与上皮细胞体积密度之比明显小于交界性及良性肿瘤(P<0.01)。  相似文献   
32.
高频彩超对颈部淋巴结囊性病变的诊断价值   总被引:2,自引:2,他引:0  
①目的探讨高频彩超对颈部淋巴结囊性病变的诊断价值。②方法回顾性分析25例颈部淋巴结囊性病变的高频彩超表现。③结果颈部淋巴结囊性病变见于颈淋巴结囊性转移瘤、化脓性淋巴结炎及淋巴结结核。其中13例为颈部淋巴结囊性转移瘤,其特征性超声表现为颈部淋巴结囊性肿大,伴囊壁实性结节;较大囊壁结节内常可探及动脉血流信号,部分囊壁结节可见微钙化。7例为颈部急性化脓性淋巴结炎,其主要超声表现为上颈部淋巴结呈单发、圆形囊性肿大;囊壁略厚,且较均匀;囊液呈细密点状回声。5例为颈部淋巴结干酪脓肿型结核,其主要超声表现为单侧或双侧中下颈部淋巴结呈多发、椭圆形囊性肿大,部分可融合成团;内壁毛糙,囊液内散在分布点状高回声。④结论高频彩超检查对颈部淋巴结囊性病变的诊断和鉴别诊断具有重要价值。  相似文献   
33.
陈伟  许晓华  李泉水  李沿江  王卫东  廖涛  孙雁 《医学争鸣》2003,24(13):1240-1242
目的:应用彩色多普勒超声心动图指导经皮二尖瓣球囊成形术(PBMV)治疗风湿性二尖瓣狭窄的价值、方法:运用彩超对行PBMV的患进行术前术后检查,观察二尖瓣钙化程度及部位、开口形状、瓣口面积、二尖瓣返流(MR)程度、瓣下病变、左房左室大小、左房有无血栓.结果:91例PBMV术后患中,术后MR72例,其中MR新出现19例,MR加重8例、与术前对比,术后二尖瓣开放幅度、二尖瓣口面积、二尖瓣跨瓣压、二尖瓣压差半降时间较术前有明显改善趋势,左房内径、肺动脉内径较术前有缩小趋势.同时,术后左房压、右室压及肺动脉压也有下降趋势。结论:彩超能明确PBMV治疗二尖瓣狭窄的效果。影响:PBMV效果的因素较多,但二尖瓣钙化的程度、部位和瓣膜形态较为重要。  相似文献   
34.
目的:探讨经直肠彩色多普勒超声对良性前列腺增生的诊断价值。方法:采用经直肠彩色多普勒对37例良性前列腺增生患者进行检查,测量大小,计算体积,并按前列腺重量分成四组,测定、分析增生内腺动脉的血液动力学参数。分组评价增生内腺的彩色血流图。结果:随前列腺重量的增加,增生内腺血流分布逐渐增加,血流的最大流度(Vmax)、血流最低流速(Vmin)、血流阻力指数(RI)、搏动指数(PI)逐渐增加。结论:经直肠彩色多普勒检查有助于临床对前列腺增生的准确诊断。  相似文献   
35.
During the years 1959 to 1983 a doubling in the rate of homicide took place in Copenhagen. This increase was exclusively due to an increasing number of male offenders. By comparing with another Danish material, the frequency of female homicide as well as that of homicide combined with suicide was found practically unchanged since 1946, indicating that both of these kinds of homicides seem to have a background different from those of other offences of fatal violence. During the years 1959 to 1983, the criteria of selection of the defendants for a psychiatric examination for the court were fairly consistent. Examinations were performed in practically all cases, where a charge of murder raised by the police was followed by a legal trial for homicide. Less and less of the defendants, however, were hospitalized for the examination, while more were examined in The Clinic of Forensic Psychiatry in Copenhagen.  相似文献   
36.
OBJECTIVE: The purpose of this study was to investigate the incidence of the retroaortic left renal vein (RLRV) in patients with varicocele. METHODS: The left renal vein was ultrasonographically investigated for the presence of the RLRV in 140 patients with varicocele and a control group of 137 age-matched patients. The main diagnostic criteria for varicocele were the presence of a varicose vein with a diameter of 3 mm or larger at rest and with a reflux lasting more than 2 seconds during the Valsalva maneuver. The RLRV was defined as a posterior course of the left renal vein to the aorta at the level of the origin of the superior mesenteric artery. RESULTS: The RLRV was observed in 13 (9.3%) of the 140 patients with varicocele and 3 (2.2%) of the control patients. The incidence of the RLRV was found to be significantly higher in patients with varicocele compared with the control patients (P = .018, Fisher exact test). In 13 patients with the RLRV, left varicocele and bilateral varicocele were detected in 10 and 3 cases, respectively. CONCLUSIONS: In this study, the incidence of the RLRV was found to be significantly higher in patients with varicocele compared with control patients. Thus, we suggest that the presence of the RLRV may be considered one of the etiologic factors in the development of varicocele.  相似文献   
37.
Consecutive male (n=100) and female (n= 100) DSM-IV schizophrenics newly registered for treatment in a large psychiatric hospital were examined with regard to age at onset of the first psychotic symptom. Age at onset of the first psychotic symptom did not differ between the sexes regardless of whether schizophrenia was diagnosed by DSM-IV or by several alternative systems. Age at onset defined by other criteria, namely age at first contact with a physician, and age at first admission for psychiatric care, also did not show any differences between the sexes. Survival analysis of subjects having a documented date of birth revealed a female preponderance at younger ages. A higher positive symptom score predicted older age at onset of the first psychotic symptom in the total sample. These findings call into question the universality of the traditional view of a younger age at onset of schizophrenia among males. Tentative neurodevelopmental and cultural explanations are presented to explain why there is no sex difference in age at onset of schizophrenia in India.  相似文献   
38.
Purpose: To disclose the structure of visual pigment gene for a protanopia with specific variation.Methods: Exon 5 fragments of the red andgreen visual pigment genes from the protanopia with specific varnation as well as controls were amplified by poly-merase chain reaction (PCR). The PCR products were put through heteroduplex-SSCP analysis and PCR-RFLP (restriction fragement length polymorphism) analysis to clarify the specific variation. The specific variation of the exon 5 DNA fragment from the protanopia was identified by sequencing.Results: A novel 5'green-3'red hybrid gene fragment without the normal red and green visual pigment gene was discovered in the protanopia. He should only have a single visual pigment gene, 5'green-3'red hybrid gene, on his X chromosome. The fusion point is between codon 285 and codon 296 in exon 5. Conclusion : Unequal intragenic recombination may occur in exon 5 as well as its upstream. A 5'green-3'red hybrid gene may present independently on the X chromosome without ac  相似文献   
39.
Sex differences in home range size and spatial ability are predictive of sex differences in the relative size of the hippocampus in rodents. Such differences in behavior and hippocampal volume are presumed to be, in part, the result of differences in perinatal exposure to hormones. We predicted from differences in the size of home ranges of male and female Mongolian gerbils (Meriones unguiculatus) in the wild that the hippocampus of male gerbils would be relatively larger than that of females. We examined the effect of prenatal hormonal influences on hippocampal size by comparing hippocampal volume of males and females from 2F and 2M intrauterine positions to that of randomly selected males and females. We found that, as predicted, randomly selected males had a significantly larger hippocampus, relative to telencephalon, than did randomly selected females. However, males and females from 2F and 2M intrauterine positions did not differ in relative hippocampal size. Possible explanations for the absence of a sex difference in hippocampal size in male and female gerbils from 2F and 2M intrauterine positions are discussed.  相似文献   
40.
There is no method available to compare the fit of two non-hierarchical non-linear mixed effects models, although the common practice is to select the model with the lower objective function. Bootstrapping the log-likelihood differences (LLDs) of non-hierarchical models and constructing a bootstrap confidence interval on the LLDs is proposed for comparing the goodness-of-fit of such models. This is illustrated with different parameterizations of clearance models for an anti-infective agent in a longitudinal pharmacokinetic study which are compared. Additive and exponential models of creatinine clearance as a predictor of clearance are used as examples.  相似文献   
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