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991.
OBJECTIVE: To more clearly define the relationship between an oxygen flux test, oxygen supply dependency, and outcome in patients with sepsis, severe sepsis, or septic shock. DESIGN: Prospective, interventional clinical trial. SETTING: A teaching hospital general intensive care unit in London, UK. PATIENTS: A total of 36 patients with sepsis, severe sepsis, or septic shock were studied during a 10-month period. INTERVENTIONS: After resuscitation, patients were given an intravenous infusion of dobutamine at 10 microg/kg/min for 1 hr. Cardiac and respiratory variables were measured before the infusion and then while the infusion was in progress. Any patient who was able to increase his or her oxygen consumption by >15% was designated a responder to the test. MEASUREMENTS AND MAIN RESULTS: Hemodynamic, oxygen transport, and lactate measurements were made at baseline and after 1 hr of the dobutamine infusion. All patients were then followed up until hospital discharge. Responders to this test had a hospital mortality of 14%, whereas nonresponders had a mortality of 91% (p<.01). The responders were characterized by being younger (p<.05), having higher Acute Physiology and Chronic Health Evaluation III scores (p<.05), and having a greater requirement for inotropic support (p<.05). After the test, the responders had significantly higher oxygen delivery (p<.01) and oxygen consumption (p<.05) than the nonresponders, as well as a significantly greater temperature increase as a result of the infusion (p<.05). The nonresponders were unable to increase either oxygen delivery or oxygen consumption to the dobutamine. This test was highly predictive of outcome (p<.0001). The identification of an increase in both oxygen delivery and oxygen consumption (oxygen supply dependency) was not associated with a poor outcome. CONCLUSION: A dobutamine oxygen flux test provides evidence of the intrinsic function of cells. The inability of these cells to increase oxidative metabolism during sepsis, as indicated by the dobutamine test, is associated with a high mortality.  相似文献   
992.
993.
Acute myocardial infarction occurred in a 43 year-old premenopausal woman with controlled hypertension and no known coronary artery disease following the use of the antimigraine medications sumatriptan succinate injectable form and methysergide maleate. The use of sumatriptan is contraindicated within 24 hours of using ergotamine or ergotamine-type medications such as methysergide. This contraindication is based on the theoretical possibility of prolonged vasospasm with the combined use. Methysergide is primarily a serotonin type 2 (5-HT2) antagonist, although it does act as a partial agonist at 5-HT1 receptors. It is believed that a major component of coronary artery vasospasm is possibly due to 5-HT supersensitivity mediated by 5-HT1Dbeta receptor activation. Drugs that selectively stimulate the 5-HT(D) receptors, such as sumatriptan, are potentially hazardous in people with underlying coronary artery disease, and agents with additional agonistic properties at these receptors may potentiate this effect. Physicians should be warned to inquire about prior 24-hour medication use before prescribing antimigraine medication.  相似文献   
994.
Dimensionality of parkinsonian signs in aging and Alzheimer's disease   总被引:1,自引:0,他引:1  
BACKGROUND: Parkinsonian signs are commonly found on the neurologic examination of older persons and are associated with morbidity and mortality. The extent to which parkinsonian signs in aging and Alzheimer's disease cluster in groups typical of Parkinson's disease has not been investigated previously. METHODS: The motor portion of the Unified Parkinson's Disease Rating Scale (UPDRS), or a version with minor modifications, was administered to more than 2,800 persons in three cohorts: (a) 637 older persons with a wide range of neurologic conditions participating in the Chicago Health and Aging Project, a study of common health problems of a random sample of older persons from a geographically defined biracial community population; (b) 638 relatively healthy and highly educated older persons from 25 Catholic religious communities participating in the Religious Orders Study, a longitudinal clinical-pathologic study of aging; and (c) 1,546 older persons undergoing evaluation for possible dementia at the Rush Alzheimer's Disease Center, an urban, tertiary care center that evaluates persons for possible dementia. Separate factor analyses were performed on each data set. Additional analyses examined the factor structure in subsets by gender and race. RESULTS: A similar grouping of items emerged in each cohort and did not differ substantially by gender or race. The factors corresponded closely with the traditional grouping of parkinsonian signs into bradykinesia, gait disturbance, rigidity, and tremor. CONCLUSIONS: The grouping of parkinsonian signs is consistent in diverse samples of older persons and does not vary substantially across gender or race. The results provide an empirical basis for summarizing the principal motoric manifestations of parkinsonism.  相似文献   
995.
Epidermolysis bullosa is a group of hereditary blistering disorders for which there is no definitive therapy. Wound care is an important component of management. Regular dressing changes are required to protect blistered and eroded skin, and to prevent secondary infection and sepsis. These dressing changes can be very painful for patients with extensive erosions. We report our experience of pain management in an 11-year-old boy with severe junctional epidermolysis bullosa. Amitryptiline and cognitive behavioral techniques were effective in relieving chronic pain and discomfort. Oral midazolam 0.33 mg/kg administered 20 minutes prior to baths and dressing changes substantially improved his tolerance of wound care.  相似文献   
996.
Binding affinities of a series of 44 beta-carbolines with various substituents at the 3-, 4-, 6- and 7-positions are reported at 5 distinct recombinant GABAA/benzodiazepine receptor (BzR) subtypes [alpha x beta 3 gamma 2 (x = 1-3, 5, 6)]. Many of these ligands displayed better selectivity for the alpha 1 containing GABAA isoform. The most selective BCCT 2 and SPH 195 (17) displayed potent affinity (Ki = 0.72 and 7.2 nM for the alpha 1 beta 3 gamma 2 receptor subtype, respectively) and an overall selectivity of 20 and 23 fold, respectively, for the alpha 1 beta 3 gamma 2 receptor subtype. These are the most selective ligands in vitro for the alpha 1 containing GABAA/Bz receptor isoform reported to date to our knowledge. QSAR studies of these ligands for each receptor subtype have been carried out via a Comparative Molecular Field Analysis (CoMFA) and an included volume analysis. Geometries and charge distributions of these ligands have been optimized using ab initio methods (J. Med. Chem., 1992, 35, 4001-4010). Active conformations of flexible 3-alkoxylated beta-carbolines have been examined via a CoMFA approach. QSAR studies via CoMFA support the previous hypothesis that beta-carbolines with different intrinsic activities may follow an alternative alignment rule when they bind into the pharmacophore/receptor site of the BzR. Examination of binding affinities of beta-carbolines by this modeling strategy has established some of the differences, in particular, topologic differences between the lipophilic pockets in the alpha 1 beta 3 gamma 2, alpha 2 beta 3 gamma 2, alpha 3 beta 3 gamma 2, alpha 5 beta 3 gamma 2 and alpha 6 beta 3 gamma 2 subtypes as well as some of the similarities among the pharmacophore/receptor models of these five distinct GABAA/Bz receptor subtypes.  相似文献   
997.
998.
Mutation testing in melanoma families: INK4A, CDK4 and INK4D.   总被引:3,自引:0,他引:3  
The INK4A gene which codes for the cyclin-dependent kinase (CDK) inhibitor INK4A or p16 underlies susceptibility to melanoma in some families. Germline mutations in the gene that codes for the target protein of p16, CDK4, underlie susceptibility in very rare families. We report mutation screening of the INK4A and CDK4 genes in 42 UK families. A total of nine families were identified with INK4A mutations and none with CDK4 exon 2 mutations. These mutations were in 8/22 (35%) families with three or more cases of melanoma and 1/20 (5%) families with only two cases. In one of these nine families a novel single base pair substitution was identified, Gly67Arg. In an attempt to identify another melanoma susceptibility gene, a member of the INK4 family, the p19 INK4D gene has been studied. The p19 gene was sequenced in DNA from the 42 UK families and six additional US families. No mutations were identified.  相似文献   
999.
Economic evaluations of new AIDS treatment drugs are important. For physicians treating patients with Kaposi's sarcoma, these issues are especially meaningful since cancer treatment costs for this group of patients are high. Kaposi's sarcoma is the most frequently occurring neoplasm in AIDS patients, affecting about 15% of this population. In our study, a retrospective economic evaluation has been made based on data from two randomized phase III clinical studies of severely immune-compromised HIV-infected individuals and which compares liposomal doxorubicin with liposomal daunorubicin. We have estimated the cost and cost effectiveness of the two drugs. The costs per complete or partial response are USS 18340 for daunorubicin and USS 8871 for doxorubicin. The incremental cost per additional responder by using liposomal doxorubicin instead of liposomal daunorubicin is USS 1910. Sensitivity analysis shows that these results hold over a wide range of assumptions.  相似文献   
1000.
Up-regulation of ephrin-A1 during melanoma progression.   总被引:14,自引:0,他引:14  
Ephrin-A1, formerly called B61, is a new melanoma growth factor; it is angiogenic and chemoattractant for endothelial cells. EPH-A2, or ECK (a receptor for ephrin-A1), is ectopically expressed in most melanoma cell lines; the pathology where this expression is first manifested and the possible role of the receptor in tumor progression are unknown. To determine these, we studied the expression of this ligand and receptor in biopsies of benign and malignant melanocytic lesions. EPH-A2 was not detected in normal melanocytes, benign compound nevi or advanced melanomas, though it was found in 2 of 9 biopsies of malignant melanoma in situ. Ephrin-A1 was present in occasional early lesions and in advanced primary melanomas (43%) and metastatic melanomas (67%). Expression of ephrin-A1 was induced in melanoma cells by pro-inflammatory cytokines. Our findings are consistent with 2 possible roles for ephrin-A1 in melanoma development: it may promote melanocytic cell growth or survival and induce vascularization in advanced melanomas. Both effects may be potentiated by inflammatory responses. Our data are consistent with earlier observations that an inflammatory infiltrate is associated with poor prognosis in thin primary melanomas.  相似文献   
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