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Staurosporine (3-100 nM), frequently used as a protein kinase C (PKC) inhibitor, increased accumulation of nitrite in the culture medium of rat peritoneal macrophages up to 6 times above the control level. Moreover, when used in combination with the stable analogue of cyclic AMP, dibutyrylcyclic AMP (db cyclic AMP; 0.1 mM), and/or a cytokine, tumour necrosis factor-alpha (TNF alpha; 100 u ml-1), staurosporine synergistically potentiated, up to 30 times, nitrite accumulation. On the other hand, the other PKC inhibitors, calphostin C and H-7 (10 nM-10 microM) were not effective under the same conditions. The staurosporine-induced nitrite accumulation, in both the presence and the absence of TNF alpha and/or db cyclic AMP was effectively inhibited by the protein synthesis inhibitor, cycloheximide, or by the nitric oxide (NO) synthesis inhibitor, NG-monomethyl-L-arginine (L-NMMA). Thus our data suggest that staurosporine may enhance NO production in macrophages via intracellular mechanisms unrelated to the PKC inhibition.  相似文献   
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Eighteen patients received gastrectomy for primary cancer of the gastric remnant were studied clinico-histopathologically. Gastric ulcer had been the most common condition requiring previous gastric surgery, and Billroth II resection had been the most often employed procedure. The cancer of the gastric remnant was in an advanced stage in all patients. Tumors were detected in the sutured or anastomosed region (especially the latter) of the remnant stomach in a great majority of the patients studied. In spite of combined resection of the adjacent organs, such as spleen, pancreas and colon in most patients, curative resection could be done in only a half of them and the prognosis was poor in general. These observations seem to stress the importance of following up gastrectomized patients periodically and precautiously by endoscopic examination with multiple biopsy, because early detection of cancer of remnant stomach may lead to improvements in therapeutic results.  相似文献   
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Ovarian protein content and fat body protein synthesis were measured during the first gonotrophic cycle in virgin female Blaberus discoidalis cockroaches. Protein synthesis was measured for in vitro fat bodies from animals treated with combinations of a juvenile hormone analog (JHA = methoprene) and corpora cardiaca (CC) extracts. Ovarian protein content began to increase on Day 5 of adult life and reached its maximum at Days 20-22. Synthesis of proteins secreted by the in vitro fat body increased by 12-fold between emergence and its maximum on Day 18, then declined to nearly its original level by Day 33. Synthesis of nonsecreted, fat body proteins increased by 4-fold between emergence and a maximum on Day 21, then declined. CC extracts and JHA were administered to decapitated females to determine their regulative effects on fat body protein synthesis. The synthesis by the fat body of nonsecreted proteins was increased by both JHA and CC extracts. In contrast, synthesis of secreted proteins increased only in the presence of JHA. CC extracts, alone, had no effects on the synthesis of secreted proteins, but administration of CC extracts in combination with JHA increased the synthesis of the secreted proteins by 55% above that observed with JHA alone. SDS-PAGE of proteins secreted into the medium by the in vitro fat body demonstrated that JHA stimulated the synthesis of specific polypeptides, whereas CC extracts did not affect the synthesis of specific-secreted polypeptides. These results suggest that JH regulates specific protein synthesis by the fat body of B. discoidalis; neurohormones elevate the general capacity of the fat body for protein synthesis and amplify the specific effects of JH.  相似文献   
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Since October 1985, the New Jersey Department of Health (NJDOH) has required hospitals to report all patients with a discharge diagnosis of asbestosis. As follow-up to a needs assessment survey of these patients, the NJDOH developed an educational packet including an information bulletin titled “Asbestos Disease: Medical and Legal Facts for Employees” and a pre-stamped postcard evaluation survey. The packet was sent to 1,418 patients reported by hospitals; 433 patients returned the evaluation questionnaire. The survey assessed attitudinal responses (were the materials helpful and easy to understand?) and behavioral responses (did the respondent plan on discussing the materials with a doctor or lawyer?) to the information in the packet. Of the postcard respondents, 85% found the materials helpful, and approximately half indicated that they would discuss the materials with a doctor or lawyer. Of the 33% who were proxy respondents, half appeared not to have understood that the materials had relevance to them as family members. Modifications to the protocol for the asbestos disease educational packet were made based on the evaluation data. Limitations of the evaluation survey and the value of process evaluations in risk communication projects are discussed. © 1993 Wiley-Liss, Inc.  相似文献   
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The advent of systems biology approaches that have stemmed from the sequencing of the human genome has led to the search for new methods to diagnose diseases. While much effort has been focused on the identification of disease-specific biomarkers, recent efforts are underway toward the use of proteomic and metabonomic patterns to indicate disease. We have developed and contrasted the use of both proteomic and metabonomic patterns in urine for the detection of interstitial cystitis (IC). The methodology relies on advanced bioinformatics to scrutinize information contained within mass spectrometry (MS) and high-resolution proton nuclear magnetic resonance (1H-NMR) spectral patterns to distinguish IC-affected from non-affected individuals as well as those suffering from bacterial cystitis (BC). We have applied a novel pattern recognition tool that employs an unsupervised system (self-organizing-type cluster mapping) as a fitness test for a supervised system (a genetic algorithm). With this approach, a training set comprised of mass spectra and 1H-NMR spectra from urine derived from either unaffected individuals or patients with IC is employed so that the most fit combination of relative, normalized intensity features defined at precise m/z or chemical shift values plotted in n-space can reliably distinguish the cohorts used in training. Using this bioinformatic approach, we were able to discriminate spectral patterns associated with IC-affected, BC-affected, and unaffected patients with a success rate of approximately 84%.  相似文献   
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Recombinant bacteriophage expressing Brucella abortus antigens have been isolated from a lambda gt11 expression library by using antibody raised against a sodium dodecyl sulfate-polyacrylamide gel electrophoresis-purified cell envelope protein of 36 kilodaltons. Fusion products expressed by these recombinants vary in apparent molecular mass by sodium dodecyl sulfate-polyacrylamide gel electrophoresis but only slightly exceed the size of beta-galactosidase. Western blot (immunoblot) analysis of crude lysates derived from lambda gt11 lysogens indicates that the fusion products react specifically with the original antisera used for recombinant selection and selectively bind antibody directed against the 36-kilodalton cell envelope protein. Analysis of the DNA inserts from 11 independently selected recombinants reveals similar-size EcoRI fragments which range in size from 150 to 300 base pairs (bp), all of which cross-hybridize via Southern blot analysis. Three independently selected EcoRI inserts ranging in size from 200 to 270 bp have been subcloned into M13mp18 and sequenced; all three contain a common region of about 200 bp. Southern blot analysis of B. abortus genomic DNAs digested with EcoRI, PstI, or DdeI indicates the presence of two fragments which hybridize to these DNA probes while single BamHI and HindIII fragments hybridize. The absence of these sites from the internal DNA sequence of the cloned probes suggests the presence of more than one copy of these sequences within the B. abortus genome. The same DNA probes have been used to select genomic clones of approximately 20 kbp from a lambda 2001 library. The lambda 2001 recombinants contain single BamHI fragments and two PstI fragments which hybridize to these oligonucleotide probe constructed on the basis of the amino-terminal sequence of the mature gene product hybridizes to the same BamHI and PstI fragments as the lambda gt11-derived DNA probe. Although the relative positions of the oligonucleotide sequences and the lambda gt11 insert within the genes is not known, the two sequences flank a region which corresponds to at least 40% of the size of the predicted gene. Additional experimentation must be performed to determine whether these sequences represent either two complete structural genes encoding major cell envelope proteins or repetitive sequences within a single structural gene.  相似文献   
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Early dental caries detection will facilitate implementation of nonsurgical methods for arresting caries progression and promoting tooth remineralization. We present a method that combines optical coherence tomography (OCT) and Raman spectroscopy to provide morphological information and biochemical specificity for detecting and characterizing incipient carious lesions found in extracted human teeth. OCT imaging of tooth samples demonstrated increased light backscattering intensity at sites of carious lesions as compared to the sound enamel. The observed lesion depth on an OCT image was approximately 290 microm matching those previously documented for incipient caries. Using Raman microspectroscopy and fiber-optic-based Raman spectroscopy to characterize the caries further, spectral changes were observed in PO4 (3-) vibrations arising from hydroxyapatite of mineralized tooth tissue. Examination of various ratios of PO4 (3-) nu2, nu3, nu4 vibrations against the nu1 vibration showed consistent increases in carious lesions compared to sound enamel. The changes were attributed to demineralization-induced alterations of enamel crystallite morphology and/or orientation. OCT imaging is useful for screening carious sites and determining lesion depth, with Raman spectroscopy providing biochemical confirmation of caries. The combination has potential for development into a new fiber-optic diagnostic tool enabling dentists to identify early caries lesions with greater sensitivity and specificity.  相似文献   
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