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41.
Pituitary stalk meningioma: case report   总被引:1,自引:0,他引:1  
We report a 45-year-old woman with a meningioma which was in contact with only the pituitary stalk on MRI. As the pituitary stalk has no dura mater, we suggest this tumour may have originated from the arachnoid membrane of the pituitary stalk. Though some reports have shown that meningiomas can arise from sites lacking a dural component, this is the first report of a meningioma originating from the pituitary stalk. Received: 21 December 1995 Accepted: 26 February 1996  相似文献   
42.
The cell organization of the pituitary gland and the relationship between neurohypophysis and adenohypophysis in the early developmental stages of the gilthead sea bream, Sparus aurata, were studied by electron microscopy. In newly hatched larvae, the pituitary gland was embedded in the ventral floor of the diencephalon and separated from the hypothalamus by a continuous basal lamina. Elongated mesenchymal cells next to the ventral surface were observed. At this stage, there was no neurohypophysis and the adenohypophysis consisted of undifferentiated endocrine cells with small scarce secretory granules and a few stellate cells, with no distinctive zonation. An incipient neurohypophysis was present in 1-day-old larvae. The first evagination of the neurohypophysis into the adenohypophysis were observed in 2-day-old larvae and developed progressively with age, being deeper in the caudal zone. Two regions in the adenohypophysis, one anterior — the presumptive pars distalis — and one posterior — the presumptive pars intermedia — were found in 2-day-old larvae. Three regions (rostral and proximal pars distalis and pars intermedia) were clearly distinguishable in 4-day-old larvae. The ultrastructural features of the pituitary endocrine cells varied during gland differentiation, with the secretory granules gradually increasing in number and size, accompanying organelle development. Nevertheless, even in the oldest larvae studied (65 days), undifferentiated cells similar to those in the earliest stages were observed. The first blood vessels appeared in the neurohypophysis around 16 days after hatching. During early development, the pituitary gland progressively emerged from the ventral floor of the brain. By 16 days, the principal pattern of the pituitary gland architecture appeared to be established.  相似文献   
43.
The community-based course presented is a longitudinal course running through four semesters in the Faculty of Medicine, University of Gezira, Sudan. Students combine their regular work in primary health care centres with attachments to a number of families in Wad Medani town. They continue to visit these families regularly throughout their entire medical course with the aim of studying them and helping them with some of their medical and psychosocial problems.  相似文献   
44.
目的:探讨大肠癌术后早期肠梗阻的诊断与治疗。方法:回顾分析在肠癌手术412例术后早期肠梗阻29例的临床资料。结果:20例经手术探查发现以机械性梗阻占多数(18/20),手术治愈18例;死亡2例,死亡原因均为延误手术时机造成;非手术治愈9例。结论:大肠癌术后早期肠梗阻虽有梗阻症状,但由于术后诸多因素的影响,大多缺乏典型机械性肠梗阻的临床表现。处理中先进行适当时间的非手术治疗,无缓解者再手术。  相似文献   
45.
急性中风中脏腑证型与垂体-肾上腺轴激素关系的研究   总被引:6,自引:0,他引:6  
目的 :探讨急性中风中脏腑证型与垂体—肾上腺轴激素的促肾上腺皮质激素 (ACTH)、皮质醇 (CS)的关系。方法 :对 78例中脏腑患者进行辨证分型 ,同时利用放射免疫分析 (RIA)法测定血中 ACTH、CS含量 ,按证型分为四组 ,对比不同证型间 ACTH、CS的水平 ,并与健康人组 (60例 )作对照。结果 :ACTH、CS含量水平比较 :1四种证型的 ACTH、CS均比正常健康人组高 (P <0 .0 0 1 ) ;2四种证型间比较有明显差异 (P<0 .0 1 ) ,从高到低为 :痰热内闭心窍证 >风火上扰清窍证 >痰湿蒙塞心神证 >元气败脱、心神散乱证。结论 :ACTH、CS含量水平可作为判别中脏腑不同证型间的微观指标  相似文献   
46.
尿路复合性恶性肿瘤(附21例报告)   总被引:4,自引:0,他引:4  
报告21例尿路复合性恶性肿瘤,位于肾盂2例,膀胱19例。主要临床表现为血尿,绝大多数病人伴有尿路刺激症状。低分化的移行细胞癌(TCC)与继发性复合肿瘤有密切关系。21例中1例为TCC复合肉瘤,11例为TCC复合鳞癌,7例为TCC复合腺癌,2例为腺癌复合鳞癌。本组2例肾盂肿瘤分别行肾输尿管全长加膀胱袖口状切除术和肾部分切除术,术后存活6个月和1年;膀胱肿瘤14例行膀胱部分切除术,已生存3年4例,1年2例,未满1年2例,3例1~2年内死亡,失访3例;2例根治性膀胱全切术已生存5年和3年以上;3例行TURBt,已生存3年1例,15年1例,未满1年1例。对尿路复合性恶性肿瘤的组织学、临床和病理特征进行了讨论。  相似文献   
47.
A comparison of 121 mature-age and 270 normal-age entrants who graduated from the University of Queensland Medical School between 1972 and 1987 shows that mature-age entrants are some 7 years older, are more likely to come from public (state) schools and less likely to have parents in professional/technical occupations. Otherwise, the two groups were similar in terms of gender, marital status, number of children, ethnic background and current practice location. The educational background of mature-age entrants prior to admission includes 44.6% with degrees in health-science areas and 31.4% with degrees in non-health areas. Reasons for delayed entry of mature-age entrants include late consideration of medicine as a career (34.7%), financial problems (31.4%), dissatisfaction with previous career (30.6%), poor academic results (19.8%), or a combination of the above factors. Motivations to study medicine include family influences (more so in normal-age entrants), altruistic reasons (more so in mature-age entrants) and a variety of personal/social factors such as intellectual satisfaction, prestige and financial security (similar for both groups) and parental expectations (more so in normal-age entrants). Mature-age entrants experienced greater stress throughout the medical course, especially with regard to financial difficulties, loneliness/isolation from the students and family problems (a greater proportion were married with children). While whole-course grades were similar in both groups, normal-age entrants tended to win more undergraduate honours/prizes and postgraduate diplomas/degrees, including specialist qualifications. Practice settings were similar in terms of group private practice, hospital/clinic practice or medical administration, but there was a greater proportion of mature-age entrants in solo private practice, and a smaller proportion in teaching/research. If given the time over, some two-thirds of both groups would choose medicine as a career. Reasons for job satisfaction include helping patients, intellectual stimulation and financial rewards. Reasons for dissatisfaction include pressure of work, red-tape/paperwork, 'doctor-bashing', long working hours, emotional strain, financial pressure, unfulfilled career expectations and irritation with trivial medical complaints.  相似文献   
48.
The purpose of this study was to assess the degree of consistency in student ratings of teacher effectiveness during the first year of medical school. Student ratings of teaching effectiveness represent a commonly used source of information that enters into the academic decision-making process. In medical school, student evaluations often represent a major source of information that is used in promotion and tenure decisions. It is essential that the precision of such ratings be ascertained so that decision-makers will know how much confidence to place in this source of information on teaching effectiveness. In this study, each member of a first-year medical school class was randomly assigned a two-digit identification number at the beginning of the spring semester, 1986. As the semester progressed students were asked to evaluate each full-time teacher in three major courses. Multiple instructors were utilized in each course (n = 10). Each teacher was evaluated immediately after lectures during the first (T1) and second (T2) halves of the course. Students evaluated the teacher a third time (T3) as part of the end-of-semester overall course evaluation. The teachers were evaluated on a short eight-item Likert-type scale that identified several key indicators of effective teaching. Students attached their anonymous identification numbers to individual ratings so that their responses could be matched in the analysis. The results indicate that medical students are only moderately consistent in the extent to which they evaluate teachers. This inconsistency varied by course and by instructors within courses.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
49.
1962~1986年25年间,经尸检病理确诊的29例新生儿肺出血,以早产儿和低出生体重儿为主,生后一周内发病者27例。本组20例有窒息史,口鼻有血性分泌物流出者17例。本文描述了新生儿肺出血的临床表现和病理特征,以及对新生儿肺出血的病因作了讨论。  相似文献   
50.
Teaching of medical ethics   总被引:1,自引:0,他引:1  
Teaching medical ethics in Manchester within the introductory course of obstetrics and gynaecology is a joint activity with the Centre for Social Ethics and Policy. This interdisciplinary teaching has evolved through lecture sessions with small-group discussions dealing with topics of interest in human reproduction. The small-group discussion have been replaced by an open debate conducted by the students. Their own involvement and participation and an exposure to the disciplines of the humanities has broadened their approach to different ways of problem-solving of these real issues.  相似文献   
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