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141.
A two-week elective to introduce first- and second-year medical students to primary care internal medicine was developed and evaluated. Course time is divided between conference sessions (25 percent) provided by full-time clinical faculty members and office experience (75 percent) provided by volunteer clinical faculty members (general internists in private practice and in prepaid health plans). Evaluations by the students (n = 58) who took the elective consisted of a questionnaire assessment of the conference session topics, the student's ability to carry out course objectives, and the preceptor's teaching activities. The conference topics were highly rated, with a mean score of 4.1 on a rating scale ranging from 1 (unfavorable) to 5 (favorable). The course objectives and teaching activities were also well rated, with a mean score of 4.1 and 3.9, respectively, on a rating scale ranging from 1 (none) to 5 (outstanding). 相似文献
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145.
The use of the monoclonal antibody Ki-67 in the identification of proliferating cells: application to surgical neuropathology 总被引:6,自引:0,他引:6
In order to test its potential application to surgical neuropathology, the monoclonal antibody Ki-67 was used to demonstrate immunohistochemically the proliferating cells in 40 neoplasms of the nervous system. The antibody, which reacts with a nuclear protein expressed in the G1, G2, S, and M phases of the cell cycle, was demonstrated in frozen sections of all lesions. The highest incidence of stained nuclei was found in a metastatic carcinoma (57%). The percentage of stained cells in gliomas was in general agreement with the histologic grade and known biologic behavior of the lesions, ranging from 0.6% in a pilocytic astrocytoma to 12.4% in a glioblastoma multiforme. In the fibrillary astrocytic neoplasms of low cellularity, there were good correlations between the percentages of stained cells and the degrees of nuclear pleomorphism and chromatin density. In meningiomas, schwannomas, and a cerebellar hemangioblastoma, the fractions of labeled nuclei were less than 1%. The percentage of stained cells in pituitary adenomas showed considerable variation among the four cases (0.2-1.5%), the biologic significance of which is unknown. In four of the above cases, Ki-67 staining was performed on air-dried squash preparations with excellent visualization of immunoreactive nuclei. In one case, a hemangioblastoma, no stained nuclei were seen. The results confirm that Ki-67 staining is technically suitable as a diagnostic method, with good correlations between frozen sections and smear preparations. Determination of the replicating cell fraction could become an important additional criterion to predict the biologic behavior of nervous system neoplasms. 相似文献
146.
Horner's syndrome or oculosympathetic paralysis is not an uncommon finding in patients with head and neck neoplasms. While in most cases the syndrome is easily established at the bedside, it can be confirmed and topographically defined as a central, preganglionic, or postganglionic lesion through sequential pharmacologic testing. The importance of such localization lies in differentiating neoplasia vs. a benign condition as the cause of the syndrome. Such variants as congenital Horner's, an alternating Horner's, and a pseudo-Horner's syndrome are discussed in regard to their differential features. 相似文献
147.
148.
Between May 1984 and January 1988, 18 patients (31 pyeloureteral units) with documented symptomatic cystine stones were treated. Stone size ranged from 5 to 56 mm. in largest diameter, with an average of 21 mm. All pyeloureteral units were treated initially by endourological methods, including ureteroscopy in 10, percutaneous ultrasonic lithotripsy in 9, extracorporeal shock wave lithotripsy (ESWL) in 10 and chemolysis in 2. Of the patients 10 required a combination of these technologies and 2 required an open operation. Of the 31 units 23 were free of stones when the patient was discharged from the hospital. Of 8 patients with retained stones only 3 had fragments greater than 3 mm. in diameter. Based on this experience an algorithm was developed for the urological management of cystine stones. Ureteral calculi may be removed by ureteroscopic techniques or manipulated into the renal pelvis and managed as renal stones. Cystine renal calculi of less than 1.5 cm. may be treated with ESWL monotherapy. Stones of 1.5 to 3 cm. may be treated with ESWL and dissolution, or percutaneous ultrasonic lithotripsy plus dissolution. Staghorn calculi may be treated by percutaneous ultrasonic lithotripsy plus ESWL and/or dissolution for retained fragments. 相似文献
149.
Single-channel K+ currents recorded from the somatic and dendritic regions of cerebellar Purkinje neurons in culture 总被引:4,自引:0,他引:4
Voltage-sensitive K+ channels were studied in rat cerebellar Purkinje neurons in culture using the single-channel recording technique. Recordings in the cell-attached and outside-out configuration revealed multiple voltage-sensitive K+ channel types in patches from both the somatic and the dendritic regions. K+ channel types were present in all patches studied. The same channel types were observed in somatic and dendritic recordings. Channel types were identified by reversal potential, single-channel conductance, voltage sensitivity, and patterns of activity. In cell-attached patches recorded under physiological conditions, 3 channel types were identified. Mean single-channel conductances were 92, 57, and 12 pS. All 3 channel types were activated by membrane depolarization. Similar channel types were identified in inside-out and outside-out patches recorded under physiological conditions. Two additional channel types were identified in the outside-out patches, with mean single-channel conductances of 41 and 26 pS. In cell-attached recordings under symmetrical K+ conditions, 6 channel types were identified. Mean single-channel conductances were 222, 134, 39, 25, 14, and 15 pS. Channel types with mean conductances of 222, 134, and 39 pS required membrane depolarization for activation. A comparison of channel properties indicated that these channel types correlated with the 3 channel types observed in cell-attached patches under physiological conditions. The 3 smaller-conductance channel types (25, 14, and 15 pS) were active at potentials around rest or at hyperpolarized membrane potentials. Two K+ channel types (39 and 25 pS) were commonly associated with the late phase of extracellularly recorded spontaneous spike events, suggesting a functional role in the repolarizing phase of somatic and dendritic action potentials. These results demonstrate that voltage-sensitive K+ channels are a prominent component of both the somatic and the dendritic membrane of the cerebellar Purkinje neuron and support the view that multiple voltage-sensitive K+ channel types contribute to the membrane functions of both cellular regions in this CNS neuronal type. 相似文献
150.
B A Fallon B T Walsh C Sadik J B Saoud V Lukasik 《The Journal of clinical psychiatry》1991,52(6):272-278
BACKGROUND: One previous follow-up study suggested that inpatient bulimic women do quite poorly; after an interval of 2 to 5 years, only 13% were recovered. To examine the course and outcome of a sample of patients with bulimia nervosa that was severe enough to require inpatient hospitalization, the authors conducted the following study. METHOD: Women (N = 52) with DSM-III-R bulimia nervosa were sought 2 to 9 years after hospitalization. Prior to contact, a retrospective chart review was conducted to determine global functioning and admission diagnoses. At follow-up, patients participated in a 4 to 6 hour interview that assessed current and lifetime Axis I disorders (SCID-I), current Axis II disorders (PDE), eating behaviors (EAT, BSQ, EDI, PSR), global functioning (GAF), social adjustment (SAS-SR), and treatment and medical problems experienced since discharge. To assess the significance of differences between the recovered and the currently bulimic women, Yates-corrected chi-square tests and two-tailed t tests were used. RESULTS: Of the 52 women, 46 were interviewed, 1 had died, and 5 could not be located. Of the 46 interviewed women, 39% had fully recovered, 20% had partially recovered, and 41% were currently bulimic. The likelihood of recovery increased with length of time since discharge. While medical problems related to the bulimia were few, treatment with phenelzine was associated with three reports of serious hypertensive episodes, one of which led to death. Global functioning before hospitalization, lifetime DSM-III-R Axis I diagnoses, and current Axis II diagnoses were not associated with outcome. CONCLUSIONS: These findings suggest that even severely ill bulimic patients have a significant chance of achieving full recovery. 相似文献