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151.
Early tangential excision sometimes results in considerable blood loss, prolonged operative time, and partial loss of the graft secondary to hematoma formation. Previous reports document positive hemostatic effects and improved skin fixation with fibrin "glue." The commercial preparation used in Europe, however, has not been approved by the United States Food and Drug Administration because of the high risk of hepatitis and human immunodeficiency virus transmission. Using a method developed at the University of Virginia, we applied single-donor fibrin glue as an adjunct in early excision and grafting in 16 patients (26 hands). The overall graft take was 99%. In all patients, better adherence of the split-thickness graft to the recipient bed, during and immediately after application, was noted. We have observed no negative effects with regard to infection or healing. We recommend the use of single-donor fibrin glue to reduce operative blood loss, improve survival and ease of graft application, and possibly to accelerate healing. 相似文献
152.
Richard A. Winegar John W. Phillips Louise H. Lutze William F. Morgan 《Somatic Cell and Molecular Genetics》1990,16(3):251-256
The isoschizomer pair MspI and HpaII were used to investigate whether the putative specificity of restriction endonucleases would be maintained when they were introduced into mammalian cells. Although both enzymes recognize the sequence CCGG, HpaII will cut only if the internal cytosine is unmethylated, whereas MspI will cut regardless of the methylation status. Cleavage results in a cohesive-end DNA double-strand break, which can lead to the formation of chromosome aberrations. Since mammalian DNA is heavily methylated, one would expect MspI to be much more effective than HpaII at inducing chromosome aberrations in Chinese hamster ovary cells. In fact, during G1, MspI induced a >90-fold higher number of aberrations than did HpaII. Cell cycle studies indicated that during early S there was a 30-fold increase in HpaII-induced aberrations. This increase may be due to increased accessibility of replicating hypomethylated DNA. Cells that were treated with the demethylating agent 5-aza-2-deoxycytidine (AzdC) displayed only a moderate increase in HpaII-induced aberrations during G1. This observation, together with the results of restriction enzyme analysis of genomic DNA, indicated that demethylation was incomplete. The effects of AzdC on the induction of aberrations by MspI suggested that AzdC increases chromatin accessibility. Our results were consistent with the expected specificity of MspI and HpaII. Thus, it appears that restriction endonucleases can play a useful role in determining the biological consequences of DNA double-strand breaks. 相似文献
153.
Gillies RR Shortell SM Anderson DA Mitchell JB Morgan KL 《Hospital & health services administration》1993,38(4):467-489
Given the pressures for health care reform, interest in the concept of integrated or organized delivery systems as a means to offer more coordinated cost-effective care is growing. This article has two primary objectives: (1) to clarify the different types of integration associated with the notion of an organized delivery system, and (2) to share the results from an ongoing study of 12 organized delivery systems. The findings indicate a moderate level of integration overall, particularly in the areas of culture, financial planning, and strategic planning. The study found that corporate staff respondents perceive their systems to be more integrated and effective than do operating unit managers, and that some functional integration areas are positively associated with both physician-system and clinical integration that, in turn, are positively related to each other. Overall, perceived integration was found to be positively associated with perceived effectiveness. 相似文献
154.
We determined the prevalence of recent cocaine and alcohol use among motor vehicle fatalities occurring in New York, NY, from 1984 through 1987. Recent cocaine use was detected at autopsy in 18.2% of the sample and no significant difference between drivers (20.0%) and passengers (13.9%) was found. Both alcohol and cocaine metabolites were found in 10.0% of cases tested. The prevalence of cocaine metabolites or alcohol detected in driver fatalities aged 16 through 45 years did not change significantly when the period prior to the widespread availability of "crack" cocaine (1984 through 1985) was compared with the period immediately following the introduction of crack cocaine (1986 through 1987). Additional studies are needed both to elucidate the association between cocaine use and these fatalities and to determine the value of screening persons seriously injured in traffic accidents in areas where such drug use is endemic. 相似文献
155.
Plutonium-237 decays mainly by electron capture with a half-life of 45 d. Alpha particles are emitted in only 5 x 10(-3)% of its disintegrations. This nuclide can now be produced with relatively small amounts of alpha-emitting contaminants so that, in principle, 237Pu can be used for studies of Pu biokinetics in man. However, because of its high specific activity, there was some doubt that its metabolism would be the same as that of the alpha- and beta-emitting isotopes of Pu normally encountered in the nuclear industry. In this study, the biokinetics of nearly "pure," high specific activity 237Pu are compared with those of lower specific activity, "impure" 237Pu containing significant amounts of alpha-emitting Pu, following administration to rats by intravenous injection as the citrate. Both the distribution and excretion of the "pure" and "impure" 237Pu used in the two studies were similar and also in good agreement with the results of previously reported studies using 239Pu and 241Pu citrate, thus validating the use of 237Pu for studies of Pu metabolism in man. Data on the biokinetics of 237Pu nitrate are also included. 相似文献
156.
Interactions between imidazoline compounds and sulphonylureas in the regulation of insulin secretion
Mirna Mourtada Colin A Brown Stephen A Smith Valerie Piercy Susan L F Chan Noel G Morgan 《British journal of pharmacology》1997,121(4):799-805
- Imidazoline α2-antagonist drugs such as efaroxan have been shown to increase the insulin secretory response to sulphonylureas from rat pancreatic B-cells. We have investigated whether this reflects binding to an islet imidazoline receptor or whether α2-adrenoceptor antagonism is involved.
- Administration of (±)-efaroxan or glibenclamide to Wistar rats was associated with a transient increase in plasma insulin. When both drugs were administered together, the resultant increase in insulin levels was much greater than that obtained with either drug alone.
- Use of the resolved enantiomers of efaroxan revealed that the ability of the compound to enhance the insulin secretory response to glibenclamide resided only in the α2-selective-(+)-enantiomer; the imidazoline receptor-selective-(−)-enantiomer was ineffective.
- In vitro, (+)-efaroxan increased the insulin secretory response to glibenclamide in rat freshly isolated and cultured islets of Langerhans, whereas (−)-efaroxan was inactive. By contrast, (+)-efaroxan did not potentiate glucose-induced insulin secretion but (−)-efaroxan induced a marked increase in insulin secretion from islets incubated in the presence of 6 mM glucose.
- Incubation of rat islets under conditions designed to minimize the extent of α2-adrenoceptor signalling (by receptor blockade with phenoxybenzamine; receptor down-regulation or treatment with pertussis toxin) abolished the capacity of (+)-and (±)-efaroxan to enhance the insulin secretory response to glibenclamide. However, these manoeuvres did not alter the ability of (±)-efaroxan to potentiate glucose-induced insulin secretion.
- The results indicate that the enantiomers of efaroxan exert differential effects on insulin secretion which may result from binding to effector sites having opposite stereoselectivity. Binding of (−)-efaroxan (presumably to imidazoline receptors) results in potentiation of glucose-induced insulin secretion, whereas interaction of (+)-efaroxan with a second site leads to selective enhancement of sulphonylurea-induced insulin release.
157.
Sloan NE Peroutka JA Morgan DE Ross MB Mutnick AH 《Topics in hospital pharmacy management / Aspen Systems Corporation》1994,14(3):1-12
Influencing prescribing practices and the implementation of pharmaceutical care utilizing the drug use evaluation (DUE) process at a 891-bed teaching hospital are described. The DUE program has been structured to provide for significant pharmacy involvement while maintaining medical staff responsibility as outlined by the Joint Commission on Accreditation of Healthcare Organizations. A multidisciplinary approach is used to identify problems and develop prescribing criteria and educational initiatives. Pharmacists provide drug therapy monitoring and engage in clinical interventions and documentation of outcomes on a daily basis. DUE program pharmacists help target possible interventions, assure monitoring and outcome documentation, and compile results of all initiatives for reporting purposes to the medical staff and quality assessment program. Specific performance compliance and problems are identified and incorporated into the credentialing process. Corrective measures are determined by the Pharmacy and Therapeutics (P&T) Subcommittee with subsequent actions carried out by peer physicians. The net result is a positive influence on prescribing practices that improves the appropriate and effective use of drugs and improves patient outcomes. 相似文献
158.
It has been suggested that albumin reduces quinidine capillary permeability (PS) in the single-pass perfused heart preparation by reducing paracellular transport of quinidine ions. Using this preparation, we examined the effect of albumin (0.1 per cent) on quinidine PS at perfusate pHs of 7.1 and 7.9 during uptake of quinidine (19 µM) and also during washout of the drug using a randomized design. Quinidine PS was approximately 16 ml/min/g heart at pH 7.9 and was not altered by the presence of albumin in perfusate. At pH 7.1, in the absence of albumin, quinidine PS was also 16 ml/min/g, but in the presence of albumin (0.1 per cent) PS was reduced significantly to approximately 5 ml/min/g (P < 0.001). In the absence of albumin PS was the same at pH 7.1 and 7.9 in spite of a greater degree of ionisation of quinidine at pH 7.1. This suggests that there is significant uptake of ionised quinidine at pH 7.1. The greater effect of albumin on PS at pH 7.1 supports the hypothesis that albumin reduces paracellular transport of quinidine ions. 相似文献
159.
Some recent scientific advances in the study of the cannabinoids are outlined. The mode of action of marihuana and the cannabinoids has now been described. They belong to a new class of drug that acts on a hitherto undescribed neuro-physiological system. An endogenous neurotransmitter or neuromodulator for this system has been isolated, identified and named “anandamide”. These findings throw new light and imbue new confidence for the future of the therapeutic application of compounds derived from and related to the cannabinoids and anandamide. An outline is also provided of the current knowledge and future potential of cannabinoids in therapeutics. The effect of the current legal classification of the cannabinoids on the research and development of these compounds is discussed. 相似文献
160.
A review of parameters influencing the prognosis of patients with stages IV and IIA-B carcinoma of the cervix treated with radiotherapy alone is presented. The effect of tumor diameter, a factor not included in the International Federation of Gynecology and Obstetrics staging system, is emphasized. Potential alternative treatment strategies, particularly adjuvant hysterectomy, are addressed. 相似文献