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21.
Shah-Hwa Chou Eing-Long Kao Chien-Chih Lin Meei-Feng Huang 《Clinical autonomic research》2006,16(3):240-242
A total of 114 patients with various sympathetic disorders underwent endoscopic sympathetic block over different thoracic
ganglions by the clipping method. The advantages of this method include the recognition of the clipped level, changeability,
and reversibility. However, 4.4% of patients were unilaterally clipped at the wrong level. 相似文献
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Three cases of proved peritoneal carcinomatosis were examined by magnetic resonance imaging (MRI). Air was used to distend the entire gastrointestinal tract via an antegrade method. The findings included seedings along the small intestine, transverse and sigmoid colon, stellate pattern in the mesentery, plaque-like and bulky tumor masses in the mesentery and greater omentum, and focal thickenings along the right subdiaphragmatic parietal peritoneum. Stenosis caused by tumor encasement at the duodenojejunal junction and ileocolic anastomosis were first detected by MRI and later confirmed by barium studies. Ascites was present in all cases. One case showed ascites located only along the left paracolic gutter. This report shows that MRI is also able to demonstrate peritoneal carcinomatosis by using air as a gastrointestinal contrast medium. 相似文献
24.
The purpose of this study is to develop an evaluation instrument with high feasibility and acceptability, and to quantify the outcome of evaluation, in order to set up an efficient evaluation system. Teaching evaluation with questionnaire by students has been carried out in National Yang-Ming Medical College for two years. With the support of both teachers and students, the system has been established and conducted on a regular basis. The most important purpose of evaluation is to improve the quality of teaching. During the two academic years (Sep. 1986-June 1988) of the program, the overall response rate was 44.5%, the Department of Nursing had the highest response rate, followed by Dentistry, Medicine-Post Graduate, Medical Technology, and Medicine. Taking into consideration of the year and the class size, the regression analysis found that higher year or smaller size of the class had better response rate. The response rates dropped significantly after the first academic year regardless of department or year. A total of 23 classes were included in the evaluation program and 99 courses were evaluated. All questions in the questionnaire used a 0 to 4 ordinal scale, in which 0 (improvement needed) was the low end and 4 (excellent) the high end. The mean score of the seven questions of teaching evaluation was 2.47. As a whole, the students were satisfied with the teaching. As to the categories of courses, clinical courses had better mean score than basic medical courses, and basic medical courses had better mean score than common required courses. To evaluate the effectiveness of the teaching, students' achievement was used as the outcome variable. The most important predictive variable was the method of instruction, followed by the content of lecture such as degree of difficulty of the lecture and cognitiveness of the contents. The above 3 variables explained 76% of the variation of the students' achievement. However, the significant of teachers' speech, performance and attitude were not so influential. Analysis based on the characteristics of the teachers (sex, age, position, and teaching experience), the characteristics of students (department and year), teaching environments (time and place), and the 3 categories of courses (clinical, basic medical and common required courses) showed that all the above variables only explained less then 10% of the variation of the students' achievement. 相似文献
25.
Cytoskeletal perturbations have been associated with exposures to a variety of toxic agents as well as a number of human pathological conditions. We have observed dramatic alterations in the organization of microtubules (MT), a major component of the cytoskeleton, in 3T3 cells exposed to Ni2+. Severe perinuclear bundling and aggregation of MT occurred in both a time- and dose-dependent fashion, and this MT damage was reversible upon removal of Ni2+ from the culture media. To understand the mechanism of the Ni2(+)-induced MT change, we investigated the effect of Ni2+ (0.01 to 3.0 mM) on in vitro tubulin polymerization. Ni2+ at lower concentrations (0.01 to 1.0 mM) had little or no significant effect on the kinetics of MT polymerization. In contrast, in the presence of 1.5 to 2.0 mM Ni2+, a significant promoting effect on both the rate and the final extent of polymerization was observed. However, at Ni2+ concentrations higher than 2.0 mM, such stimulatory effect on the rate and the final extent of tubulin polymerization declined. Furthermore, the promoting effects of Ni2+ on MT polymerization were accompanied by a significant decrease in the lag period. Electron microscopic examination of samples of the polymerization product showed that MT, polymerized in the presence of 2.0 mM Ni2+, appeared more numerous and shorter (1.10 +/- 1.02 microns) than those of control (3.81 +/- 2.29 microns; p less than 0.005). This was probably a direct result of an increase in the number of initiation centers in the presence of Ni2+ as a consequence of the decreased critical concentration (7%, p less than 0.05) necessary for polymerization to occur. Our results suggest that Ni2+ may exert its toxic effect on MT in cultured cells by altering the normal kinetics of MT polymerization. 相似文献
26.
Retrograde air insufflation in MRI: A technical note 总被引:2,自引:0,他引:2
Retrograde air insufflation was employed to distend the colon and the ileum in 18 patients and five volunteers for magnetic resonance examination. Good and moderate marking of the ileum was obtained in 18 cases. The colon was nearly completely distended in every case. Intraluminal tumor, mural thickening, and extraluminal lesion were outlined by intraluminal air and surrounding air-distended bowel. This study shows that retrograde air insufflation is a useful method to mark the colon and most parts of the ileum. 相似文献
27.
S. Patricia Chou 《Alcoholism, clinical and experimental research》1994,18(1):149-153
Excessive alcohol consumption causes damages to the stomach or duodenum by impairing the integrity of the mucosal barrier. The aim of this study was to estimate the association between alcohol consumption and peptic ulcer, utilizing a large representative sample of the U.S. population, while controlling for cigarette smoking and major sociodemographic variables. Results indicated that alcohol consumption only minimally increased the odds of peptic ulcer. Thus, this study offers little support for the association between ethanol intake and peptic ulcer. 相似文献
28.
INVOLVEMENT OF NON-NMDA AND NMDA RECEPTORS IN GLUTAMATE-INDUCED PRESSOR OR DEPRESSOR RESPONSES OF THE PONS AND MEDULLA 总被引:1,自引:0,他引:1
SY Chen WC Wu CJ Tseng JS Kuo CY Chai 《Clinical and experimental pharmacology & physiology》1997,24(1):46-56
1. Fifty-five intact and six baroreceptor denervated and vagotomized cats of either sex were anaesthetized intraperito-neally with urethane (400 mg/kg) and a-chloralose (40 mg/kg). Responses of the systemic arterial pressure (SAP), mean SAP (MSAP) and sympathetic vertebral nerve (VNA) and renal nerve activities (RNA) were recorded. 2. In intact animals, monosodium L-glutamate (Glu, 0.1 mol/L, 50 nL) was microinjected into pressor areas of the locus coeruleus (LC), gigantocellular tegmental field (GTF), rostral ventrolateral medulla (RVLM) and dorsomedial medulla (DM), and the depressor areas of caudal ventrolateral medulla (CVLM). The induced actions were compared before and after microinjection of either glutamate antagonists, glutamate diethylester (GDEE, 0.5 mol/L, 50–100nL), a competitive AMPA receptor blocker, or 2-amino-5-phosphonovaleric acid (D-AP5, 0.025 mol/L, 50–100 nL), a competitive N-methyl-D-aspartate (NMDA) receptor blocker. GDEE completely blocked the increases of SAP and VNA elicited from all pressor areas. D-AP5 only partially blocked the pressor but slightly blocked VNA and RNA responses from LC, GTF and DM, particularly those from RVLM. Neither GDEE nor D-AP5 blocked the depressor responses of SAP and two nerve activities elicited from CVLM. 3. In baroreceptor denervated animals, NMDA (2 mmol/L, 50–100 nL) and AMPA (0.2 mmol/L, 50–100 nL) were micro-injected into the same pressor areas of GTF, RVLM and DM and the depressor area of CVLM responsive to Glu activation (0.1 mol/L, 30 nL). In RVLM, DM and CVLM, the results of either NMDA or AMPA were similar to those induced by Glu. However, in GTF, microinjection of either NMDA or AMPA did not induce similar responses to Glu. This suggests that the nature of GTF may differ from RVLM and DM. 4. The above results suggest that the Glu-induced pressor responses from LC, GTF, DM and especially RVLM, are primarily mediated through AMPA receptors. The Glu-induced depressor responses from CVLM may not be predominantly mediated by either AMPA or NMDA receptors. 5. In both baroreceptor-intact and -denervated cats stimulation of the pressor areas often produced an increase of VNA and a decrease of RNA, while in the depressor CVLM decreased both VNA and RNA. The VNA, but not RNA were positively correlated with the pressor responses, while both VNA and RNA were positively correlated with the depressor responses. This may suggest that neurons of the sympathetic vertebral and renal nerves are topographically organized in the brain. 相似文献
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