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581.
BACKGROUND: Studies of length of stay (LOS) in hospital usually focus on physician-independent factors. In this study, the authors identified physician-dependent factors and tested an intervention aimed at them to determine its effect on LOS. METHODS: A prospective comparison of LOS on 2 general medical wards in a tertiary care teaching hospital before and after the intervention. The pre-intervention (control) period and the intervention period were each 4 weeks. The intervention consisted of a checklist for planning management and discharge. RESULTS: Overall, the mean LOS was shorter during the intervention period than during the control period, but the difference was not statistically significant (12.0 and 14.4 days respectively, p = 0.13). The difference was significant on ward A (11.0 v. 14.7 days respectively, p = 0.02) but not on ward B (13.0 and 14.0 days respectively, p = 0.90). INTERPRETATION: An intervention at the level of the admitting physician may help to shorten LOS on a general medical ward.  相似文献   
582.
The number of fatal malignant mesotheliomas was ascertained for the period 1960-70 by contacting all pathologists in Canada. The annual incidence was steady between 1966 and 1970 at 1.4 per million population. Of 71 cases registered in 1968-70 and not previously reported, 66% were pleural, 24% peritoneal and the remainder in both sites; 45% of tumours were in women. The diagnosis of mesothelioma was approved by the Canadian Mesothelioma Panel in 59%. Sixty-nine cases were successfully investigated epidemiologically. A history of definite or probable occupational asbestos exposure was found in 30% of male cases compared with 11% of controls, but in none of the female cases or controls. However, among cases, four women and one man had had domestic exposure to dusty clothing of an asbestos worker. Most of the excess occupational exposure was in the manufacture of asbestos products or insulation and little in mining or milling. No case other than those occupationally or domestically exposed had lived within 20 miles of asbestos mines or mills.  相似文献   
583.
RNA-binding proteins have been suggested to move in association with RNA as it leaves the nucleus. The NPL3 gene of the yeast Saccharomyces cerevisiae encodes in nuclear protein with consensus RNA-binding motifs and similarity to heterogeneous nuclear ribonucleoproteins and members of the S/R protein family. We show that although Npl3 is located in the nucleus, it can shuttle between nuclei in yeast heterokaryons. In contrast, other nucleus-targeted proteins do not leave the nucleus under similar conditions. Mutants missing the RNA-binding motifs or the N terminus are still capable of shuttling in and out of the nucleus. Npl3 mutants missing the C terminus fail to localize to the nucleus. Overproduction of Npl3 in wild-type cells shows cell growth. This toxicity depends on the presence of series of unique repeats in the N terminus and localization to the nucleus. We suggest that the properties of Npl3 are consistent with it being involved in export of RNAs from the nucleus.  相似文献   
584.
1. Two peroxidases, differing in ionic character and substrate specificity, have been isolated from the tropical marine sponge Iotrochota birotulata. 2. Both peroxidases catalyze the oxidation of a number of substrates, and one peroxidase possesses a specificity similar to the terrestrial fungal enzyme chloroperoxidase. 3. Based on inhibition studies utilizing sodium azide, potassium cyanide and 8-hydroxyquinoline, it appears that the peroxidases from I. birotulata are haemoprotein complexes. 4. One peroxidase appears to possess subunit structure, and requires bound divalent metal cations for activity.  相似文献   
585.
High molecular weight autolysis products from thermolysin have been isolated and identified. The primary fragments correspond to residues 1 to 187-204 (21kD) and residues 187-204 to 316 (12kD), respectively. The fragments are both capable of independent refolding upon removal of denaturant. On the basis of these results, we suggest that the first step in the unfolding pathway of thermolysin involves unfolding of an interdomain region and domain separation. Bound calcium ions at sites 1, 2 and 4 play a major role in protecting the protein against both autolysis and unfolding, probably by stabilizing the interdomain region and enhancing domain-domain interactions.  相似文献   
586.
587.
Subjective and objective changes in smell and taste perceptionwere evaluated in 16 patients with primary hypothyroidism beforeand after thyroxine (T4) replacement and in 17 control subjects.Visual evoked responses (VER) and brainstem auditory evokedresponses (BAER) were measured in 15 patients. Although 11 ofthe patients reported subjective alterations in smell and tasteand eight of these reported resolution or improvement with euthyroidism,no improvement was found using objective measures (mean follow-up6.4 months) in smell, taste or flavour perception or in visualand auditory brainstem evoked responses. However, on a ‘scratchand sniff’ encapsulated odour identification test, hypothyroidpatients had a significant deficit in detecting and identifyingodours when compared to controls. The possibility that the deficitwas due to age differences between the two groups is discussed.  相似文献   
588.
589.
Di-(2-ethylhexyl)phthalate (DEHP), when fed at high levels in the diet for two years, is reportedly an hepatocarcinogen to rats and mice. Radioactivity from ethylhexyl-labeled, but not from phthalate-labeled, [14C]-DEHP is associated with highly purified DNA from the livers of treated rats and this radioactivity is not accounted for by assumptions of adsorption, intercalation, attachment to RNA or histones, an impurity in the labeled DEHP, or artifactual binding during sample workup. Spontaneous binding of radioactivity to DNA from either ethylhexyl-labeled DEHP or its total urinary metabolites could not be detected. Although rat liver slices generated all of the known metabolites of DEHP in vitro, no binding to DNA occurred. Administration of dual 3H/14C-labeled DEHP to rats yielded liver DNA whose 3H/14C ratio was inconsistent with the attachment of any reasonable multi-carbon fragment from the ethylhexyl portion to the DNA. The observation that roughly 100 times as high a percentage of the 14C administered was found in urea as in total DNA suggests that the 14C entered DNA through carbamyl phosphate, a precursor of both urea and pyrimidine bases. If this is the case, the association of C-1 from the ethylhexyl portion of DEHP with DNA may not involve alteration of the DNA or genetic damage.  相似文献   
590.
The study evaluated the effects of dietary doses of Lactobacillus plantarum VSG3 on the growth performance, immunity, and disease resistance of Labeo rohita juveniles against Aeromonas hydrophila infection. Fish (mean body weight 60 g) were fed with diet containing 0 (control), 106, 108, 1010 cfu g?1 L. plantarum VSG3 for 60 days. Various growth and immune parameters were examined at 30 and 60 days of post-feeding. Fish were challenged with A. hydrophila 60 days post-feeding and mortalities were recorded over 10 days post-infection. Results showed that administration of VSG3 for 60 days had significant effects (P < 0.05) on the specific growth rate (SGR) and feed utilization efficiency of L. rohita. Dietary administration of L. plantarum VSG3 significantly increased the serum lysozyme and alternative complement pathway (ACP) activities, phagocytosis and respiratory burst activity in L. rohita throughout the experimental period. The highest superoxide dismutase (SOD) activity (P < 0.05) was observed in the fish group fed diet containing VSG3 at 108 cfu g?1. The serum IgM levels were significantly higher in the experimental groups compared to the control group after 30 days of feeding; but, the result was opposite after 60 days of feeding. Further, fish fed the diet containing 108 cfu g?1 L. plantarum VSG3 had significantly higher (P < 0.05) post-challenge survival rate (77.7%). These results collectively suggest that dietary supplementation of L. plantarum VSG3 at 108 cfu g?1 to L. rohita is optimal for enhancing the growth, immunity, and disease resistance against A. hydrophila infection.  相似文献   
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