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1.
An inhibitor of Aspergillus flavus has been isolated from peanuts and identified as 5,7-dimethoxyisoflavone. Authentic 5,7-dimethoxyisoflavone, synthesized from benzyl-2-hydroxy-4,6 dimethoxyphenyl (3), and the isolated compound display identical ultraviolet spectra in methanol, in methanol+sodium methoxide, and in methanol+AlCl3; similar behavior in solvent extraction, column chromatography, TLC, and fungal inhibition.  相似文献   
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A series of environmental and clinical isolates of Sporothrix schenckii being studied in our laboratories under standard conditions of temperature, humidity and media, displayed, in some of the isolates, large dematiaceous hyphae. The large hyphae could be seen to produce the fine hyphae associated with S. schenckii on which typical microconidia developed. Typical microconidia also developed occasionally on the large hyphae, and strands of the unusually large hyphae also were seen to form arthroconidia. Some strains formed large, thin-walled cells on thin and/or thick hyphae resembling the balloon cells seen in mature colonies of Trichophyton tonsurans.All strains which have demonstrated these various and unusual structures histopathologically produced typical sporotrichosis in laboratory animals. When reisolated from these animals, the cultures again exhibited the unusual structures, as well as those typical of S. schenckii.  相似文献   
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OBJECTIVE--To assess the validity, reliability, and acceptability of the short form 36 (SF 36) health survey questionnaire (a shortened version of a battery of 149 health status questions) as a measure of patient outcome in a broad sample of patients suffering from four common clinical conditions. DESIGN--Postal questionnaire, followed up by two reminders at two week intervals. SETTING--Clinics and four training practices in north east Scotland. SUBJECTS--Over 1700 patients aged 16-86 with one of four conditions--low back pain, menorrhagia, suspected peptic ulcer, or varicose veins--and a comparison sample of 900 members of the general population. MAIN OUTCOME MEASURES--The eight scales within the SF36 health profile. RESULTS--The response rate exceeded 75% in the patient population (1310 respondents). The SF36 satisfied rigorous psychometric criteria for validity and internal consistency. Clinical validity was shown by the distinctive profiles generated for each condition, each of which differed from that in the general population in a predictable manner. Furthermore, SF36 scores were lower in referred patients than in patients not referred and were closely related to general practitioners'' perceptions of severity. CONCLUSIONS--These results provide support for the SF36 as a potential measure of patient outcome within the NHS. The SF36 seems acceptable to patients, internally consistent, and a valid measure of the health status of a wide range of patients. Before it can be used in the new health service, however, its sensitivity to changes in health status over time must also be tested.  相似文献   
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Spore suspensions from 7 day old cultures of Curvularia lunata (Wakker) Boedijn var. aeria (Batista, Lima and Vasconcelos) M.B. Ellis were added to soil samples originally devoid of Curvularia propagules. The test fungus disappeared after six weeks of inoculation irrespective of soil amendments, like the application of green manure, urea, superphosphate, or soil cropped to Sorghum (dura) or cotton seedlings.  相似文献   
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Unlike many higher plants Euphorbia granulata and E. heterophylla do not encourage the development of fungi in their rhizospheres. Fungi recovered therefrom were limited both in number and range of species. The rhizosphere of E. heterophylla was slightly favourable to soil fungi when compared with the other weed plant. Aspergillus niger was least affected by both types of rhizosphere. Expressed latexcontaining sap of E. granulata was remarkably inhibitory to submerged cultures of A. flavus, A. nidulans, Fusarium sp., Curvularia sp. and Helminthosporium. Conidia and mycelial fragments recovered from these cultures failed either to germinate or resume growth thus exhibiting an antifungal property of E. granulata latex.  相似文献   
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The effect of neurotensin on submaximally-stimulated hepatobiliary and pancreatic secretion was studied in 6 healthy subjects. An intravenous infusion of neurotensin 1.4 ± 0.3 pmol/kg/min, designed to reproduce plasma neurotensin immunoreactivity levels within the physiological range, produced a significant increase in pancreatic bicarbonate output. Plasma concentrations of pancreatic polypeptide rose by 83 ± 16 pmol/l and were associated with a small reduction in trypsin, but no significant change in bilirubin outputs.  相似文献   
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Hepatitis C virus (HCV) subtypes are pre-requisite to predict endemicity, epidemiology, clinical pathogenesis, diagnosis, and treatment of chronic hepatitis C infection. HCV genotypes 4 and 1 are the most prevalent in Saudi Arabia, however; less consensus data exist on circulating HCV subtypes in infected individuals. This study was aimed to demonstrate the virological surveillance, phylogenetic analysis, and evolutionary relationship of HCV genotypes 4 and 1 subtypes in the Saudi population with the rest of the world. Fifty-five clinical specimens from different parts of the country were analyzed based on 5′ untranslated region (5′ UTR) amplification, direct sequencing, and for molecular evolutionary genetic analysis. Pair-wise comparison and multiple sequence alignment were performed to determine the nucleotide conservation, nucleotide variation, and positional mutations within the sequenced isolates. The evolutionary relationship of sequenced HCV isolates with referenced HCV strains from the rest of the world was established by computing pairwise genetic distances and generating phylogenetic trees. Twelve new sequences were submitted to GenBank, NCBI database. The results revealed that HCV subtype 4a is more prevalent preceded by 1a in the Saudi population. Molecular phylogeny predicts the descendants’ relationship of subtype 4a isolates very close to Egyptian prototype HCV strains, while 1a isolates were homogeneous and clustering to the European and North American genetic lineages. The implications of this study highlight the importance of HCV subtyping as an indispensable tool to monitor the distribution of viral strains, to determine the risk factors of infection prevalence, and to investigate clinical differences of treatment outcomes among intergenotypic and intragenotypic isolates in the treated population.  相似文献   
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