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排序方式: 共有3282条查询结果,搜索用时 15 毫秒
981.
R Liefooghe JB Baliddawa EM Kipruto C Vermeire AO De Munynck 《Canadian Metallurgical Quarterly》1997,2(8):809-821
Early passive case finding and treatment compliance are the cornerstones of tuberculosis (TB) control programs. As human behavior plays a critical role in both strategies, a better understanding of it is important for the planning and implementation of a successful TB programme, especially for the health education component, Our qualitative study in Uasin Gishu, Kenya, aimed at a better understanding of the community's beliefs and perceptions of TB, recognition of early symptoms and health-seeking behavior. Five focus groups with a total of 49 people were held: on with hospitalized TB patients, two with rural and two with urban participants. Tuberculosis is well known in the communities and many vernacular names for the disease exist. TB is perceived as a contagious, 'sensitive' disease difficult to diagnose and treat. Community members believe that TB should be diagnosed and treated in a hospital or by a medical doctor and not at the peripheric level. TB treatment is perceived as long, agonising and cumbersome. Traditional treatment is considered a valid alternative to modern treatment, believed to be as effective and much shorter. Initial symptoms such as cough and fever are often overlooked and/or confused with malaria or a common cold. Symptoms associated with the disease refer to the later stage of TB. TB is attributed to causes such as smoking, alcohol, hard work, exposure to cold and sharing with TB patients. Many participants believe TB is hereditary. Prolonged self-treatment and consultation with the traditional health sector as well as the social stigma attached to the disease increase patient's delay. Only after symptoms persist for some time and/or the suspect's health deteriorates, are modern health services consulted. These social conditions necessitate culturally sensitive health education, taking into account local perceptions of TB. 相似文献
982.
983.
LH Wieler A Schwanitz E Vieler B Busse H Steinrück JB Kaper G Baljer 《Canadian Metallurgical Quarterly》1998,36(6):1604-1607
Shiga toxin-producing Escherichia coli (STEC) strains of serogroup 0118 are the most prevalent group among STEC strains in diarrheic calves in Germany (L. H. Wieler, Ph.D. thesis, University of Giessen, 1997). To define their virulence properties, 42 0118 (0118:H16 [n = 38] and 0118:H- [n = 4]) strains were characterized. The strains displayed three different Stx combinations (Stx1 [36 of 42], Stx1 and Stx2 [2 of 42], and Stx2 [4 of 42]). A total of 41 strains (97.6%) harbored a large virulence-associated plasmid containing hlyEHEC (hly from enterohemorrhagic E. coli). The strains' adhesive properties varied in relation to the eukaryotic cells tested. Only 28 of 42 strains (66.7%) showed localized adhesion (LA) in the human HEp-2 cell line. In contrast, in bovine fetal calf lung (FCL) cells, the number of LA-positive strains was much higher (37 of 42 [88.1%]). The locus of enterocyte effacement (LEE) was detected in 41 strains (97.6%). However, not all LEE-positive strains reacted positively in the fluorescence actin-staining (FAS) test, which indicated the attaching and effacing (AE) lesion. In HEp-2 cells, only 22 strains (52.4%) were FAS positive, while in FCL cells, the number of FAS-positive strains was significantly higher (38 of 42 [90.5%; P < 0.001]). In conclusion, the vast majority of the 0118 STEC strains from calves (41 of 42 [97.6%]) have a high virulence potential (stx, hlyEHEC, and LEE). This virulence potential and the high prevalence of STEC 0118 strains in calves suggest that these strains could be a major health threat for humans in the future. In addition, the poor association between results of the geno- and phenotypical tests to screen for the AE ability of STEC strains calls the diagnostic value of the FAS test into question. 相似文献
984.
BW Walsh LH Kuller RA Wild S Paul M Farmer JB Lawrence AS Shah PW Anderson 《Canadian Metallurgical Quarterly》1998,279(18):1445-1451
CONTEXT: Raloxifene is a selective estrogen receptor modulator that has estrogen-agonistic effects on bone and estrogen-antagonistic effects on breast and uterus. OBJECTIVE: To identify the effects of raloxifene on markers of cardiovascular risk in postmenopausal women, and to compare them with those induced by hormone replacement therapy (HRT). DESIGN: Double-blind, randomized, parallel trial. SETTING: Eight sites in the United States. PARTICIPANTS: 390 healthy postmenopausal women recruited by advertisement. INTERVENTION: Participants were randomized to receive 1 of 4 treatments: raloxifene, 60 mg/d; raloxifene, 120 mg/d; HRT (conjugated equine estrogen, 0.625 mg/d, and medroxyprogesterone acetate, 2.5 mg/d); or placebo. MAIN OUTCOME MEASURES: Change and percent change from baseline of lipid levels and coagulation parameters after 3 months and 6 months of treatment. RESULTS: At the last visit completed, compared with placebo, both dosages of raloxifene significantly lowered low-density lipoprotein cholesterol (LDL-C) by 12% (P < .001), similar to the 14% reduction with HRT (P < .001). Both dosages of raloxifene significantly lowered lipoprotein(a) by 7% to 8% (P < .001), less than the 19% decrease with HRT (P<.001). Raloxifene increased high-density lipoprotein-2 cholesterol (HDL2-C) by 15% to 17% (P < .05), less than the 33% increase with HRT (P < .001). Raloxifene did not significantly change high-density lipoprotein cholesterol (HDL-C), triglycerides, or plasminogen activator inhibitor-1 (PAI-1); whereas HRT increased HDL-C by 11% and triglycerides by 20%, and decreased PAI-1 by 29% (for all, P < .001). Raloxifene significantly lowered fibrinogen by 12% to 14% (P < .001), unlike HRT, which had no effect. Neither treatment changed fibrinopeptide A or prothrombin fragment 1 and 2. CONCLUSIONS: Raloxifene favorably alters biochemical markers of cardiovascular risk by decreasing LDL-C, fibrinogen, and lipoprotein(a), and by increasing HDL2-C without raising triglycerides. In contrast to HRT, raloxifene had no effect on HDL-C and PAI-1, and a lesser effect on HDL2-C and lipoprotein(a). Further clinical trials are necessary to determine whether these favorable biochemical effects are associated with protection against cardiovascular disease. 相似文献
985.
986.
987.
JD Arnold AD Mumford JO Lindsay U Hegde M Hagan JR Hawkins 《Canadian Metallurgical Quarterly》1997,41(3):408-410
We present a case of a 3-month-old boy presenting with fulminating meningococcal septicaemia associated with extensive peripheral gangrene requiring amputation of three limbs. The surgical management options and the role of early fasciotomy are discussed. 相似文献
988.
JA Cook SY Kim D Teague MC Krishna R Pacelli JB Mitchell Y Vodovotz RW Nims D Christodoulou AM Miles MB Grisham DA Wink 《Canadian Metallurgical Quarterly》1996,238(2):150-158
S-nitrosothiols have been shown to affect a number of physiological functions. Several techniques have been used to detect these species in biological systems, primarily by methods utilizing chemiluminescence. Since the apparatus required for measurement of chemiluminescence are not readily available in most laboratories, methods employing more conventional techniques such as uv-vis and fluorescence spectroscopy may be of greater use. Herein, we report the development of colorimetric and fluorometric methods for the reliable quantitation of S-nitrosothiols. Solutions containing sulfanilamide/N-(1-naphthyl)- ethylenediamine dihydrochloride or 2,2'-azinobis (3-ethylbenzthiazoline-6-sulfonic acid), when exposed to S-nitrosoglutathione (GSNO), S-nitrosocysteine, or S-nitrosoacteylpenicillamine, resulted in no absorbance changes in the range of 400-800 nm. Exposure to HgCl2 or Cu(acetate)2 resulted in release of nitric oxide (NO) from the S-nitrosothiols. The liberated NO reacted subsequently with oxygen and formed a chemical species which reacted with either analysis solution, resulting in an increase in absorption between 400 and 800 nm. A plot of RSNO versus absorbance was linear for both mercury(II) and copper(II) ions where the slope in the presence of mercury ion was significantly greater than that for copper ion. The sensitivity was as low as 5 microM RSNO using HgCl2. The fluorometric method using 2, 3-diaminonaphthalene as the scavenger of the NOsolidusO2 products gave a sensitivity of 50 nM for GSNO. In addition, S-nitrosylated proteins were quantitated using the fluorometric technique. These methods provide accurate determination of low concentrations of S-nitrosothiols, utilizing conventional spectroscopic techniques available in most laboratories. 相似文献
989.
JB Atkinson KL Chamberlin J de Csepel M Srikanth 《Canadian Metallurgical Quarterly》1994,29(3):379-380
In pediatric patients, central line implantation via the subclavian vein can be complicated by the presence of a kink in the peel-away sheath. A technique is described, which has been used on 62 occasions to overcome this problem. Reinserting the catheter through the kinked peel-away sheath in concert with a guidewire that extends 3 to 4 cm beyond the catheter tip can ensure successful placement. 相似文献
990.
MH Siegelbaum JE Moulsdale JB Murphy GR McDonald 《Canadian Metallurgical Quarterly》1994,43(6):869-873
We report on 2 cases of an adrenocortical carcinoma with vena caval involvement. Preoperative evaluation included a magnetic resonance imaging (MRI) scan confirming the presence of vena caval involvement. Extremely precise detail of the vena caval tumor thrombus was very helpful in preparing for the surgical extirpation. MRI detail far outweighed what was seen on the computed tomography scan and venacavogram. The MRI scan correlated exactly with what was found surgically. Although MRI scanning has been used to evaluate renal tumors with vena caval extension, few cases have been reported with similar adrenal tumors. 相似文献