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991.
Yolanda K. Mueller Mathieu Bastard Patrick Nkemenang Eric Comte Geneviève Ehounou Sara Eyangoh Barbara Rusch Earnest Njih Tabah Laurence Toutous Trellu Jean-Francois Etard 《PLoS neglected tropical diseases》2016,10(4)
Background
Access to laboratory diagnosis can be a challenge for individuals suspected of Buruli Ulcer (BU). Our objective was to develop a clinical score to assist clinicians working in resource-limited settings for BU diagnosis.Methododology/Principal Findings
Between 2011 and 2013, individuals presenting at Akonolinga District Hospital, Cameroon, were enrolled consecutively. Clinical data were collected prospectively. Based on a latent class model using laboratory test results (ZN, PCR, culture), patients were categorized into high, or low BU likelihood. Variables associated with a high BU likelihood in a multivariate logistic model were included in the Buruli score. Score cut-offs were chosen based on calculated predictive values. Of 325 patients with an ulcerative lesion, 51 (15.7%) had a high BU likelihood. The variables identified for the Buruli score were: characteristic smell (+3 points), yellow color (+2), female gender (+2), undermining (+1), green color (+1), lesion hyposensitivity (+1), pain at rest (-1), size >5cm (-1), locoregional adenopathy (-2), age above 20 up to 40 years (-3), or above 40 (-5). This score had AUC of 0.86 (95%CI 0.82–0.89), indicating good discrimination between infected and non-infected individuals. The cut-off to reasonably exclude BU was set at scores <0 (NPV 96.5%; 95%CI 93.0–98.6). The treatment threshold was set at a cut-off ≥4 (PPV 69.0%; 95%CI 49.2–84.7). Patients with intermediate BU probability needed to be tested by PCR.Conclusions/Significance
We developed a decisional algorithm based on a clinical score assessing BU probability. The Buruli score still requires further validation before it can be recommended for wide use. 相似文献992.
Dr. Michael J. Rutten Robert G. Garrison C. Diane Moore A. Max Fiskin Laurence Y. Cheung 《Cell and tissue research》1989,258(3):555-561
Summary Electron-cytochemical localization of alkaline phosphatase activity was performed on G cells of Necturus maculosus antral mucosa. Alkaline phosphatase activity was localized to the nuclear membrane, the Golgi/endoplasmic reticulum, and the limiting membranes of G cell peptide-secretion vesicles. There was no specific localization of alkaline phosphatase activity to the plasma membrane. Treatment of the tissues with levamisole (an alkaline phosphatase inhibitor) did not markedly reduce the specific alkaline phosphatase activity. Specific lead deposition was reduced by removal of the substrate from the reaction mixture. The results from this study on N. maculosus G cells demonstrate that alkaline phosphatase activity can be found in a non-mammalian gastric endocrine cell and that specific activity was localized primarily to those intracellular structures involved with protein biosynthesis. 相似文献
993.
The conservation of scarce land resources is essential to the long-term viability of agriculture in Rwanda. High population density, steep slopes, and abundant rainfall prevail in the highland portions of this African country, making the task of erosion control uncommonly difficult for the peasant farmer. The specific use to which land is put, e.g., cultivation, fallow, pasture, woodlots, and, if it is cultivated, the particular combination of crops grown, can be seen as contributing to both the cause and the solution of the land degradation problem. Based on data from a nationwide survey of over 4800 agricultural fields in Rwanda, this study reviews the extent to which the land use and cropping patterns employed by farmers are appropriately suited, in terms of erosion control, to the topographical and environmental characteristics of their landholdings. Analyses of other aspects of the traditional agricultural system, e.g., variations in relative soil fertility, the use of organic fertilizers, and the location of fields relative to the household, are introduced to help explain why farmers often fail to maximize erosion control through land use and cropping practices. Adjustments to current land use practices that can be expected to reduce soil loss are discussed. 相似文献
994.
995.
Istvan Berczi Valerie Holford-Strevens Zamir H. Warsi Laurence S. McMorris Robert H. Thorlakson Thorburn K. Thorlakson Alec H. Sehon 《Cancer immunology, immunotherapy : CII》1983,14(3):180-184
A total of 208 plasma samples from 115 patients with gastrointestinal carcinomas and nine patients with other intestinal disease were examined for the presence of IgE tumor antibodies by a solid-phase radioimmunoassay. Approximately one-third of the patients gave significant reactions with gastrointestinal carcinoma extracts compared with normal tissue extracts. Absorption with tumor and normal tissue extracts, with type AB human red cells, and with CEA indicated tumor specificity in some of the samples so examined. None of the 50 serum samples tested from normal blood donors contained tumor-specific IgE. IgE tumor antibodies decreased or completely disappeared in the majority of patients 8-13 days after surgical treatment. 相似文献
996.
The audible cries of three species of young myomorph rodents were found to be emitted through the nose and the mouth, buccal and nasal cavity resonances being involved in the production of the formant structures of the emitted cries. Ultrasonic cries were found to be emitted mainly through the mouth, with no evidence for the involvement of cavity resonances. Nerve sectioning experiments on adult and young rats implicated the larynx as the source of both their audible and their ultrasonic cries. However, consideration of the considerable differences in physical structure between the typically "vocal" audible cries and the ultrasonic cries, as well as other differences noted in the experimental conditions here and elsewhere, leads to the conclusion that the rodent larynx may operate in two quite different sound production modes. 相似文献
997.
998.
A. J. Boakes D. R. Laurence P. C. Teoh F. S. K. Barar L. T. Benedikter B. N. C. Prichard 《BMJ (Clinical research ed.)》1973,1(5849):311-315
Intravenous infusions of phenylephrine, noradrenaline, adrenaline, and isoprenaline were given to healthy human volunteers after five to seven days on phenelzine, tranylcypromine, or imipramine, and cardiovascular responses were compared with those observed under control conditions. With monoamine oxidase inhibitors there was a 2-2½ fold potentiation of the pressor effect of phenylephrine, but no clinically significant potentiation of cardiovascular effects of noradrenaline, adrenaline, or isoprenaline. With imipramine there was potentiation of the pressor effects of phenylephrine (2-3 fold), noradrenaline (4-8 fold), and adrenaline (2-4 fold); there were dysrhythmias during adrenaline infusions, but no noticeable or consistent changes in response to isoprenaline.Noradrenaline and adrenaline in amounts contained in local anaesthetics used in dentistry are not likely to be significantly potentiated in otherwise healthy patients receiving monoamine oxidase inhibitors. Hazardous potentiation of their cardiovascular effects might occur in patients receiving tricyclic antidepressants.Our observations do not indicate that the hazards associated with isoprenaline inhalation by bronchial asthmatics would be increased by coincident therapy with a monoamine oxidase inhibitor or tricyclic antidepressant. 相似文献
999.
Factors Affecting Virulence of Shigella flexneri: Defective Methionine Synthesis in an Escherichia coli-Shigella Hybrid 下载免费PDF全文
An Escherichia coli-Shigella flexneri hybrid of intermediate virulence was studied to determine whether its shorter survival in host cells might be due to a metabolic defect. Investigation of its growth in minimal glucose medium showed that the hybrid, like its E. coli parent, had a longer lag phase and a slower growth rate than its virulent Shigella parent. Methionine was found to increase the growth rate of the hybrid. The Shigella parent of the hybrid can synthesize methionine normally, but the E. coli parent has a point mutation in its metA gene. Since it synthesizes enough methionine to grow slowly, it is postulated that the hybrid strain has a hybrid metA gene, that is, a gene composed partly of deoxyribonucleic acid (DNA) from E. coli, with the balance of the DNA from S. flexneri. Phage P1-mediated transduction, with the metA(-)E. coli parent as recipient and the Shigella parent as donor, yielded a few transductants that responded to methionine in the same way the hybrid did. Many more transductants of the hybrid type were produced when the hybrid strain was used as a donor. It is suggested that this poorly functioning gene acts synergistically with the hybrid strain's relaxed synthesis of ribonucleic acid to prevent its survival in the host. 相似文献
1000.
Escherichia coli Mutant with Elevated Nicotinamide Adenine Dinucleotide Phosphate (Reduced) Oxidase Activity 下载免费PDF全文
A slow-growing mutant of Escherichia coli with greatly elevated nicotinamide adenine dinucleotide phosphate (reduced; NADPH) oxidase activity has been isolated. The oxidase activity of the wild-type organism, normally low at pH 7.5, was increased when the assay was performed at pH 6.0. Sucrose density gradients of sonic extracts of the mutant and wild-type strains revealed several peaks of NADPH oxidase activity at pH 6.0. The parent organism had a peak of activity of high molecular weight which was absent from the mutant. The mutant strain had an activator capable of increasing the activity of all wild-type density gradient peaks, especially the one of high molecular weight. The activator was either missing or masked in the wild type. Agar gel electrophoresis of the extracts uncovered a rapidly moving band from the wild type, missing from the mutant; the material in this band had weak NADPH-diaphorase activity and strongly inhibited the activity of the mutant NADPH oxidase. It was concluded that, in wild-type E. coli, NADPH oxidase activity is regulated by a proper balance of an activator and an inhibitor. The absence of the inhibitor, as in the mutant, or the inactivation of the inhibitor at acid pH levels, results in a high level of NADPH oxidase activity. The relation of high NADPH oxidase levels and subsequent decrease of the NADPH pool to the decrease in growth rate is considered. 相似文献