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21.
BACKGROUND AND PURPOSE: Marine luminous bacteria were isolated and identified from samples in shallow coastal waters of Taiwan during the relatively warm seasons. METHODS: Identification of the luminous isolates was performed based on differences of phenotypic and genotypic characteristics together with data from phylogenetic analysis. RESULTS: Twenty seven strains of marine luminous bacteria were isolated. They were divided into five types based on differences of phenotypic characteristics. However, they could be clustered into only two genotypes according to the analysis of restriction patterns of polymerase chain reaction-amplified 16S rRNA genes digested with various restriction enzymes. The characterization data together with the 16S rRNA gene-based phylogenetic analysis revealed that the isolates included in phenotype I (seven isolates) could be Photobacterium leiognathi, and those included in phenotypes II-V (twenty isolates) might be classified as Vibrio harveyi. However, phylogeny based on gyrB sequences indicated that phenotypes II-V could be classified into two species, V. harveyi and Vibrio campbellii. CONCLUSION: Culturable luminous bacteria in the shallow coastal waters of Taiwan during the sampling period are dominated by V. harveyi/campbellii and P. leiognathi, and the former species appeared to be more prevalent and numerous than the latter species in general.  相似文献   
22.
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   
25.
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   
26.
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   
27.
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   
28.
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   
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Immunotherapy through oral routes is thought to be a valuable therapeutic option for asthma. The clinical and immunologic effects of sublingual immunotherapy (SLIT) in children with asthma caused by mites were evaluated in a double-blind, placebo-controlled study for 6 months. Patients (aged 6-12 yr) with mild-to-moderate asthma, with single sensitization to mite allergen, received either SLIT or placebo with a standardized Dermatophagoides pteronyssinus (D.p.)/D. farinae (D.f.) 50/50 extract. The cumulative dose was around 41824 IR, equivalent to 1.7 mg of D.p. and 3.0 mg of D.f. allergen. Symptom and medication scores were assessed throughout the study. Serum total immunoglobulin (Ig)E, eosinophil count, eosinophil cationic protein, specific IgE, specific IgG4, and skin sensitivity were evaluated before starting the treatment and after the treatment period. Twenty patients completed the study. At the beginning of the treatment, no differences were observed between the groups for symptom and medication scores, skin sensitivity, or immunologic parameters. After 6 months of treatment, there was a significant difference in nighttime asthma symptom scores and specific IgG4 (p < 0.05) in the SLIT group compared with the placebo group. Daytime symptom and medication scores, total IgE, eosinophil count, forced expiratory volume in 1 s, and mean evening peak expiratory flow rate reached significant differences in the SLIT group during the treatment period (p < 0.05). No severe adverse effects were reported. Our results revealed that treatment for 6 months with SLIT is clinically effective in decreasing asthmatic symptoms and medication use in children with mild-to-moderate asthma because of mite sensitivity. The clinical usefulness of this form of immunotherapy and the mechanism underlying its immunologic effects deserve further studies.  相似文献   
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