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991.
CT Bever PA Anderson J Leslie HS Panitch S Dhib-Jalbut OA Khan R Milo JR Hebel KL Conway E Katz KP Johnson 《Canadian Metallurgical Quarterly》1996,47(6):1457-1462
To examine the efficacy and toxicity of oral 3,4 diaminopyridine (DAP) in dosages up to 100 mg/day, 36 patients with multiple sclerosis (MS) enrolled in a randomized, double-blind, placebo-controlled, crossover trial. The primary outcome measure was improvement of a prospectively defined neurologic deficit, which was leg weakness in 34 patients. Secondary outcome measures included the patient's subjective response, scored manual motor testing (MMT) of leg strength, scored leg strength from videotaped motor testing (VMT), quadriceps and hamstrings strength (QMT) measured by isometric dynamometry, neuropsychological testing (NPT), ambulation index (AI), and Expanded Disability Status Scale (EDSS) score. Paresthesias and abdominal pain were common and were dose limiting in eight patients. Three patients had episodes of confusion, and one patient had a seizure while on DAP. Eight patients withdrew from the study, leaving 28 evaluable patients for the efficacy analysis. The prospectively defined neurologic deficit improved in 24 patients-22 on DAP and 2 on placebo (p = 0.0005). All improvements were in leg weakness. Subjective response and measures of leg strength and function (MMT, VMT, QMT, and AI) improved on DAP compared with placebo. Neither NPT nor EDSS scores improved. DAP treatment can induce improvements in leg strength in MS patients, but toxicity is limiting in many patients. 相似文献
992.
993.
KL Goh 《Canadian Metallurgical Quarterly》1997,12(6):S29-S35
The aim of the present study was to determine the risk factors for Helicobacter pylori in a dyspeptic Malaysian population. A cross-sectional survey of 1060 consecutive patients presenting with dyspepsia at the Endoscopic Unit, University Hospital, Kuala Lumpur, Malaysia from January 1994 to July 1995 was undertaken. All patients answered a detailed questionnaire and underwent endoscopy, with two antral biopsies taken for diagnosis of H. pylori using a rapid urease test. An overall H. pylori prevalence of 49.0% was recorded. Helicobacter pylori prevalence in relation to the major endoscopic diagnoses were as follows: non-ulcer dyspepsia (NUD) 31.2%; duodenal ulcer (DU) 91.4%; and gastric ulcer (GU) 74.1%. The prevalence among the races were as follows: Malay 16.4%; Chinese 48.5%; and Indians 61.8%. Multiple logistic regression analysis identified the following as independent risk factors: > 45 years old 1.5 (1.1,2.0); male gender 1.6 (1.2,2.1); ethnic group: Chinese 2.5 (1.7,3.7); Indians 4.9 (3.2,7.5); level of education: low 2.3 (1.5,3.5); middle 1.7 (1.1,2.6); and smoking 1.6 (1.2,2.3). Analysis was also performed on DU, GU and non-UD patients separately; in both DU and GU patients, H. pylori prevalence was high regardless of age, sex, race or level of education. However, in DU patients, Indian race had an independent risk factor (Odds ratio = 7.8 (1.2,48.4)). The findings in the NUD group reflected the findings in the ?all patients' group; > 45 years old, male gender, Indian and Chinese race, and low level of education were also significant, independent risk factors. The overall differences in H. pylori prevalence between the different subgroups were mainly due to differences in the NUD group. The increased risk of H. pylori infection in Chinese and Indians points to either an inherent ethnic genetic predisposition or to socio-cultural practices peculiar to the particular race which may be responsible for transmission of the infection. 相似文献
994.
KL Thorpe P Gorman C Thomas D Sheer J Trowsdale S Beck 《Canadian Metallurgical Quarterly》1997,200(1-2):177-183
3,5-Dihydroxy-4-isopropylstilbene (ST), an antibiotic produced by the bacterial symbiont Photorhabdus luminescens of the nematodes of the genus Heterorhabditis was determined quantitatively in nematode bacterium-infected insects using HPLC or TLC for separation and UV for quantification. Comparable and reproducible results were obtained with both HPLC-UV and TLC-UV methods. Several factors, including solvents for extraction of the antibiotic from the infected insects, eluents for TLC development and programs for HPLC operation, were investigated. Of the four solvents used, namely acetone, methanol, ethyl acetate and diethyl ether, acetone had the highest extraction efficacy, and the ST recovery rate was about 95%. ST can be easily separated from all other bacterial metabolites on a TLC plate using a mixture of chloroform-methanol (98.5:1.5) or by HPLC using acetonitrile and water as the mobile phase. 相似文献
995.
This paper reports on an ongoing investigation into health sciences faculty's information-seeking behavior, including their use of new information technologies. A survey was administered to all faculty in medicine, nursing, and pharmacy at the University of Illinois at Chicago. It was similar to one administered to the same population in 1991. The survey asked about faculty's use of electronic resources, documented any shift from the use of print to electronic formats, and measured the utilization of library training. The response rate was 48.5% for medicine faculty, 45.0% for nursing, and 62.5% for pharmacy. The study found that use of the print Index Medicus among faculty was in transition: While 30.5% continued to use the print resources, 68.0% of faculty accessed MEDLINE through electronic means. Faculty preferred accessing electronic databases from their offices to doing so from the library. Health sciences faculty used a wide variety of databases, in addition to MEDLINE, to fill their information needs. Most faculty did not take advantage of either in-house or electronic training sessions offered by librarians. The study concluded that the training preferences of faculty need to be further explored. 相似文献
996.
Developments in methods for identifying antigens from infectious agents and cancers has provided exciting new opportunities in prevention and treatment through vaccination. In many of these situations, however, traditional immunization techniques do not stimulate protective immunity because they fail to fully mobilize the appropriate immune responses. This limitation, together with new insights into the underlying mechanism of immune responses, has spurred development of several new approaches for vaccine delivery. We discuss some of the current efforts being developed to provide effective vaccine delivery systems. 相似文献
997.
U Mehlhorn SJ Allen KL Davis HJ Geissler RD Warters E Rainer de Vivie 《Canadian Metallurgical Quarterly》1998,6(3):274-281
Various mutations in the fibroblast growth factor receptor 3 (FGFR3) gene have recently been reported in thanatophoric dysplasia (TD). We examined the clinical, radiographic, and histologic findings in 91 cases from the International Skeletal Dysplasia Registry and correlated them with the specific FGFR3 mutation. Every case of TD examined had an identifiable FGFR3 mutation. Radiographically, all of the cases with the Lys650Glu substitution demonstrated straight femora with craniosynostosis, and frequently a cloverleaf skull (CS) was demonstrated. In all other cases, the femora were curved, and CS was infrequently present but was occasionally as severe as TD with the Lys650Glu substitution. Histopathologically, all of the cases shared similar abnormalities, but cases with the Lys650Glu substitution had better preservation of the growth plate. Cases with the Tyr373Cys substitution tended to have more severe radiographic manifestations than the Arg248Cys cases, but there was overlap in the phenotypic spectrum between them. One common classification of TD distinguishes affected infants based on the presence or absence of CS. In contrast, and as originally proposed by Langer et al. [1987: Am J Med Genet 3: 167-179], our data suggest that TD can be divided into at least two groups (TD1 and TD2) based on the presence of straight or curved femora. The variable presence of CS and severity of the radiologic and histologic findings in the other substitutions may be due to other genetic, environmental, or stochastic factors. 相似文献
998.
KL Wedding TM Grist JD Folts N Maalej KK Vigen DC Peters H Osman CA Mistretta 《Canadian Metallurgical Quarterly》1998,40(5):656-665
Coronary artery disease continues to be the leading cause of death for adults in the United States. Magnetic resonance imaging (MR) has the potential to dramatically impact the diagnosis of heart disease by noninvasively providing a wide range of anatomic and physiologic information. Previous research has shown that coronary flow, one component of a complete examination, can be accurately measured in the left anterior descending artery in vivo. The current work validates MR flow measurements in canine circumflex arteries using transit time ultrasound as a standard. The circumflex artery experiences greater in-plane motion and is a more stringent test for flow measurement accuracy. This work also compares two methods of processing MR velocity data, phase difference and complex difference techniques, and examines the sources of error present in the animal validation model. Phase difference processing with a 30% magnitude threshold best matched the mean ultrasound flow values (30% PD = 1.04 x US + 1.49, r = 0.94), but it was very sensitive to vessel boundary identification. The complex difference process was less sensitive to vessel boundary identification and correlated well with the transit time ultrasound despite systematic underestimations. The reasons for the discrepancies are shown to stem from a number of possible sources including variability of the ultrasound standard, low signal-to-noise ratios in the MR images, sensitivity of the MR technique to vessel boundary identification, and motion artifacts in the images. 相似文献
999.
Facial swelling caused by a periapical abscess is commonly encountered by dental practitioners. It requires prompt treatment, usually by removal of the infective foci and administration of appropriate antibiotics. However, diagnosis can be difficult, and may be complicated by the presence of retained deciduous teeth. This case report demonstrates a diagnostic dilemma and highlights the importance of looking beyond the obvious. 相似文献
1000.