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71.
Matched case‐control paired data are commonly used to study the association between a disease and an exposure of interest. This work provides a consistent test for this association with respect to the conditional odds ratio (), which is a measure of association that is also valid in prospective studies. We formulate the test from the maximum likelihood (ML) estimate of by using data under inverse binomial sampling, in which individuals are selected sequentially to form matched pairs until for the first time one obtains either a prefixed number of index pairs with the case unexposed but the control exposed or with the case exposed but the control unexposed. We discuss the situation of possible early stopping. We compare numerically the performance of our procedure with a competitor proposed by Lui ( 1996 ) in terms of type I error rate, power, average sample number (ASN) and the corresponding standard error. Our numerical study shows a gain in sample size without loss in power as compared to the competitor. Finally, we use the data taken from a case‐control study on the use of X‐rays and the risk of childhood acute myeloid leukemia for illustration.  相似文献   
72.
In order to reduce the ecotoxicity of paper mill, four different enzymatic pretreatment strategies were investigated in comparison to conventional chemical based processes. In strategy I, xylanase-aided pretreatment of pulp was carried out, and in strategy II, xylanase and laccase-mediator systems were used sequentially. Moreover, to compare the efficiency of Bacillus stearothermophilus xylanase and Ceriporiopsis subvermispora laccase in the reduction of ecotoxicity and pollution, parallel strategies (III and IV) were implemented using commercial enzymes. Conventional CDEOPD1D2 (CD, Cl2 with ClO2; EOP, H2O2 extraction; D1 and D2, ClO2) and X/XLCDEOPD1D2 (X, xylanase; L, laccase) sequences were employed with non-enzymatic and enzymatic strategies, respectively. Acute toxicity was determined by the extent of inhibition of bioluminescence of Vibrio fischeri with different dilutions of the effluent. Two-fold increase was observed in EC50 values for strategy I compared to the control process. On the other hand, sequential application of commercial enzymes resulted in higher acute toxicity compared to lab enzymes. In comparison to the control process, strategy II was the most efficient and successfully reduced 60.1 and 25.8% of biological oxygen demand (BOD) and color of effluents, respectively. We report for the first time the comparative analysis of the ecotoxicity of industrial effluents.  相似文献   
73.

Introduction

Insecticide-treated nets (ITNs) are one of the main interventions used for malaria control. However, these nets may also be effective against other vector borne diseases (VBDs). We conducted a systematic review and meta-analysis to estimate the efficacy of ITNs, insecticide-treated curtains (ITCs) and insecticide-treated house screening (ITS) against Chagas disease, cutaneous and visceral leishmaniasis, dengue, human African trypanosomiasis, Japanese encephalitis, lymphatic filariasis and onchocerciasis.

Methods

MEDLINE, EMBASE, LILACS and Tropical Disease Bulletin databases were searched using intervention, vector- and disease-specific search terms. Cluster or individually randomised controlled trials, non-randomised trials with pre- and post-intervention data and rotational design studies were included. Analysis assessed the efficacy of ITNs, ITCs or ITS versus no intervention. Meta-analysis of clinical data was performed and percentage reduction in vector density calculated.

Results

Twenty-one studies were identified which met the inclusion criteria. Meta-analysis of clinical data could only be performed for four cutaneous leishmaniasis studies which together showed a protective efficacy of ITNs of 77% (95%CI: 39%–91%). Studies of ITC and ITS against cutaneous leishmaniasis also reported significant reductions in disease incidence. Single studies reported a high protective efficacy of ITS against dengue and ITNs against Japanese encephalitis. No studies of Chagas disease, human African trypanosomiasis or onchocerciasis were identified.

Conclusion

There are likely to be considerable collateral benefits of ITN roll out on cutaneous leishmaniasis where this disease is co-endemic with malaria. Due to the low number of studies identified, issues with reporting of entomological outcomes, and few studies reporting clinical outcomes, it is difficult to make strong conclusions on the effect of ITNs, ITCs or ITS on other VBDs and therefore further studies be conducted. Nonetheless, it is clear that insecticide-treated materials such as ITNs have the potential to reduce pathogen transmission and morbidity from VBDs where vectors enter houses.  相似文献   
74.
A highly efficient laccase-producing fungus was isolated from soil and identified as Coltricia perennis SKU0322 by its morphology and by comparison of its internal transcribed spacer (ITS) rDNA gene sequence. Extracellular laccase (Cplac) from C. perennis was purified to homogeneity by anion-exchange and gel filtration chromatography. Cplac is a monomeric glycoprotein with 12% carbohydrate content and a molecular mass of 66 kDa determined by polyacrylamide-gel electrophoresis. Ultraviolet-visible absorption spectroscopy observed type 1 and type 3 copper signals from Cplac. The enzyme acted optimally at pH 3–4 and 75 °C. Its optimal activity was with 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonate) (ABTS), it also oxidized various lignin-related phenols. The enzyme was characterized as a multi-copper blue laccase by its substrate specificity and internal amino acid sequence. It showed a higher catalytic efficiency towards ABTS (kcat/Km = 18.5 s?1 μM?1) and 2,6-dimethoxyphenol (kcat/Km = 13.9 s?1 μM?1) than any other reported laccase. Its high stability and catalytic efficiency suggest its suitability for industrial applications: it detoxified phenolic compounds in acid-pretreated rice straw and enhanced saccharification yield.  相似文献   
75.
In a typical case-control study, exposure information is collected at a single time point for the cases and controls. However, case-control studies are often embedded in existing cohort studies containing a wealth of longitudinal exposure history about the participants. Recent medical studies have indicated that incorporating past exposure history, or a constructed summary measure of cumulative exposure derived from the past exposure history, when available, may lead to more precise and clinically meaningful estimates of the disease risk. In this article, we propose a flexible Bayesian semiparametric approach to model the longitudinal exposure profiles of the cases and controls and then use measures of cumulative exposure based on a weighted integral of this trajectory in the final disease risk model. The estimation is done via a joint likelihood. In the construction of the cumulative exposure summary, we introduce an influence function, a smooth function of time to characterize the association pattern of the exposure profile on the disease status with different time windows potentially having differential influence/weights. This enables us to analyze how the present disease status of a subject is influenced by his/her past exposure history conditional on the current ones. The joint likelihood formulation allows us to properly account for uncertainties associated with both stages of the estimation process in an integrated manner. Analysis is carried out in a hierarchical Bayesian framework using reversible jump Markov chain Monte Carlo algorithms. The proposed methodology is motivated by, and applied to a case-control study of prostate cancer where longitudinal biomarker information is available for the cases and controls.  相似文献   
76.
NADH oxidase (Nox) catalyzes the conversion of NADH to NAD(+). A previously uncharacterized Nox gene (LrNox) was cloned from Lactobacillus rhamnosus and overexpressed in Escherichia coli BL21(DE3). Sequence analysis revealed an open reading frame of 1359 bp, capable of encoding a polypeptide of 453 amino acid residues. The molecular mass of the purified LrNox enzyme was estimated to be ~50 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and 100 kDa by gel filtration chromatography, suggesting that the enzyme is a homodimer. The enzyme had optimal activity at pH 5.6 and temperature 65 °C, and k(cat)/K(m) of 3.77×10(7) s(-1) M(-1), the highest ever reported. Heat inactivation studies revealed that LrNox had high thermostability, with a half-life of 120 min at 80 °C. Molecular dynamics simulation studies shed light on the factors contributing to the high activity of LrNox. Although the properties of Nox from several microorganisms have been reported, this is the first report on the characterization of a recombinant H(2)O-forming Nox with high activity and thermostability. The characteristics of the LrNox enzyme could prove to be of interest in industrial applications such as NAD(+) regeneration.  相似文献   
77.
A novel series of complexes of the type [M(C(24)H(16)N(4))X(2)]; where M = Co(II), Ni(II), Cu(II), Zn(II) and Cd(II); X = Cl(-1), NO(-1)(3), CH(3)COO(-1) has been synthesized by template condensation of 1,8-diaminonaphthalene and glyoxal in the presence of divalent metal salts in methanolic medium. The complexes have been characterized with the help of elemental analyses, conductance measurements, molecular weight determination, magnetic measurements, electronic, NMR, infrared and far infrared spectral studies. The low value of molar conductance indicates them to be non-electrolytes. On the basis of various studies a distorted octahedral geometry may be proposed for all of these complexes. These metal complexes were also tested for their in vitro antibacterial and antifungal activities to assess their inhibiting potential.  相似文献   
78.
The purpose of this study was to determine the effect of permeation enhancers on the transbuccal delivery of 5-fluorouracil (FU). The effect of permeation enhancers on in vitro buccal permeability was assessed using sodium deoxycholate (SDC), sodium dodecyl sulphate (SDS), sodium tauroglycocholate (STGC), and oleic acid and their concentrations for absorption enhancement were optimized. STGC appeared to be most effective for enhancing the buccal permeation of FU than the other enhancers. These enhancements by STGC were statistically significant (p < 0.05) compared to control. The order of permeation enhancement was STGC > SDS > SDC > oleic acid. Histological investigations were performed on buccal mucosa and indicated no major morphological changes. The enhancing effect of STGC on the buccal absorption of FU was evaluated from the mucoadhesive gels in rabbits. The absolute bioavailability of FU from mucoadhesive gels containing STGC increased 1.6-fold as compared to the gels containing no permeation enhancer. The mean residence time and mean absorption time considerably increased following administration of gel containing penetration enhancer compared with the gel without penetration enhancer.  相似文献   
79.
Opportunistic fungal infections increase morbidity and mortality in COVID-19 patients monitored in intensive care units (ICU). As patients’ hospitalization days in the ICU and intubation period increase, opportunistic infections also increase, which prolongs hospital stay days and elevates costs. The study aimed to describe the profile of fungal infections and identify the risk factors associated with mortality in COVID-19 intensive care patients. The records of 627 patients hospitalized in ICU with the diagnosis of COVID-19 were investigated from electronic health records and hospitalization files. The demographic characteristics (age, gender), the number of ICU hospitalization days and mortality rates, APACHE II scores, accompanying diseases, antibiotic-steroid treatments taken during hospitalization, and microbiological results (blood, urine, tracheal aspirate samples) of the patients were recorded. Opportunistic fungal infection was detected in 32 patients (5.10%) of 627 patients monitored in ICU with a COVID-19 diagnosis. The average APACHE II score of the patients was 28 ± 6. While 25 of the patients (78.12%) died, seven (21.87%) were discharged from the ICU. Candida parapsilosis (43.7%) was the opportunistic fungal agent isolated from most blood samples taken from COVID-19 positive patients. The mortality rate of COVID-19 positive patients with candidemia was 80%. While two out of the three patients (66.6%) for whom fungi were grown from their tracheal aspirate died, one patient (33.3%) was transferred to the ward. Opportunistic fungal infections increase the mortality rate of COVID-19-positive patients. In addition to the risk factors that we cannot change, invasive procedures should be avoided, constant blood sugar regulation should be applied, and unnecessary antibiotics use should be avoided.  相似文献   
80.
Mosquito control using different methods remains an integral component of intervention programmes which aim to protect humans from various mosquito-borne diseases. The host seeking behaviour of mosquitoes is essentially guided by odorant receptor neurons housed in the antenna, maxillary palps and proboscis. The odorant receptor neurons are responsible for detecting chemical cues from hosts and also useful for developing sustainable mosquito-control strategies that exploit host-seeking behaviours. The present investigation evaluates host seeking behavioural responses of a novel, non-toxic and environment friendly repellent, ethyl 2-aminobenzoate against three known vector species of mosquitoes viz. Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus maintained in laboratory. The flight orientation of the test mosquitoes was studied using Y-tube olfactometer, whereas the antennae of adult female mosquitoes were used to investigate the effect of ethyl 2-aminobenzoate on the peripheral olfactory system using electroantennogram (EAG). The findings demonstrate that ethyl 2-aminobenzoate exhibited significant response in Y-tube olfactometer against all the three known vector species of mosquitoes. However, only Anopheles stephensi significantly elicited responses in EAG experiments, while the responses obtained for Aedes aegypti and Culex quinquefasciatus were not statistically significant. The results conclude that currently evaluated chemical ethyl 2-aminobenzoate has potential against some well established mosquito vector species and could be exploited to develop new and comparatively more effective anti-mosquito formulations.  相似文献   
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