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141.
142.
Chronic schizophrenics from three different hospitals were compared to normal subjects on skin conductance parameters. In addition to “Responders” and “Nonresponders” as reported by Gruzelier and Venables (1972), a group of “Fast Habituator” schizophrenics was found. These subjects produce one or at most two responses before habituation in an orienting series. The SC waveform of fast habituator subjects shows long latency, slow risetime and long recovery, although the amplitude of response is within normal limits.  相似文献   
143.
This report describes a spectrum of respiratory symptoms in workers exposed to trimellitic anhydride (TMA), a biologically reactive chemical used in the plastics industry. Fourteen workers who had worked on a unit which synthesized TMA were evaluated by clinical and immunologic methods. Respiratory syndromes induced by TMA inhalation included asthma and rhinitis of the immediate type, late onset asthma with systemic symptoms, and airway irritation. TMA was shown to couple rapidly to human serum albumin, forming an immunoreactive hapten-protein complex. The workers' immunologic reactivity to this complex could be quantitated and correlated with the three respiratory syndromes. The asthma-rhinitis syndrome was mediated by IgE antibody specific for the TMA hapten. The syndrome of late onset asthma with systemic symptoms was accompanied by elevated levels of TMA-specific IgG antibody. Rheumatoid factor in high titer was found in one worker with IgE-mediated asthma and in two workers with asthma of late onset. Lymphocyte reactivity of TMA-HSA was demonstrated in three workers representative of the three clinical syndromes. Leukocyte histamine release was demonstrated to TMA-HSA in one worker with high levels of IgE antibody specific for TMA-HSA who had severe symptoms of acute rhinitis and asthma.  相似文献   
144.
145.
Inhaled trimellitic anhydride (TMA) reacts with airway proteins to produce trimellityl (TM) proteins. The TM-proteins result in both systemic and local immune responses, of which various proteins present in the airway can be used for markers. Thus TM-human serum albumin (HSA), TM-IgG, and TM-IgA can be used as hapten-protein complexes for immunologic studies in sera of humans exposed to TMA by inhalation. Various immunologic assays have been established to measure antibodies against TM-proteins and have various purposes. With TM-HSA as a model antigen, total serum antibody may be measured by the ammonium sulfate technique of coprecipitation of TM-125I HSA. By solid-phase radioimmunoassays, IgE, IgG, IgA, and IgM antibodies can be measured. Lymphocyte reactivity can be measured by 3H thymidine uptake of TM-protein-stimulated lymphocytes. Biologic effects of IgE antibody can be measured by allergy skin tests and leukocyte histamine release with TM-proteins such as TM-HSA. The reaction of TMA with proteins results in alteration of those proteins that include changes in charge and physical conformation, the latter resulting in an apparent change in molecular size. These changes may relate to the observations that human antibody is not merely directed against the hapten in the hapten-human protein complex but also against new antigenic determinants formed by the TM-protein complex. Correlations have been made with certain human immunologic responses and lung disease after TMA inhalation, as follows: IgE antibody against TM-proteins correlates with TMA-induced rhinitis, conjunctivitis, and asthma; high levels of total antibody, IgG, and IgA antibody appear to correlate with the late respiratory systemic syndrome, probably a variant of hypersensitivity pneumonitis; workers exposed to TMA fumes (rather than TMA powder) have the highest levels of antibody, and this may correlate with occurrence of the hemorrhagic pneumonitis seen in this group of workers; patients with no symptoms or mild irritative symptoms have the lowest or no antibody levels. The immunopathogenetic relationships may be better understood with the further development of animal models of TMA lung disease now available.  相似文献   
146.
BACKGROUND: Patients with familial adenomatous polyposis have a nearly 100 percent risk of colorectal cancer. In this disease, the chemopreventive effects of nonsteroidal antiinflammatory drugs may be related to their inhibition of cyclooxygenase-2. METHODS: We studied the effect of celecoxib, a selective cyclooxygenase-2 inhibitor, on colorectal polyps in patients with familial adenomatous polyposis. In a double-blind, placebo-controlled study, we randomly assigned 77 patients to treatment with celecoxib (100 or 400 mg twice daily) or placebo for six months. Patients underwent endoscopy at the beginning and end of the study. We determined the number and size of polyps from photographs and videotapes; the response to treatment was expressed as the mean percent change from base line. RESULTS: At base line, the mean (+/-SD) number of polyps in focal areas where polyps were counted was 15.5+/-13.4 in the 15 patients assigned to placebo, 11.5+/-8.5 in the 32 patients assigned to 100 mg of celecoxib twice a day, and 12.3+/-8.2 in the 30 patients assigned to 400 mg of celecoxib twice a day (P=0.66 for the comparison among groups). After six months, the patients receiving 400 mg of celecoxib twice a day had a 28.0 percent reduction in the mean number of colorectal polyps (P=0.003 for the comparison with placebo) and a 30.7 percent reduction in the polyp burden (the sum of polyp diameters) (P=0.001), as compared with reductions of 4.5 and 4.9 percent, respectively, in the placebo group. The improvement in the extent of colorectal polyposis in the group receiving 400 mg twice a day was confirmed by a panel of endoscopists who reviewed the videotapes. The reductions in the group receiving 100 mg of celecoxib twice a day were 11.9 percent (P=0.33 for the comparison with placebo) and 14.6 percent (P=0.09), respectively. The incidence of adverse events was similar among the groups. CONCLUSIONS: In patients with familial adenomatous polyposis, six months of twice-daily treatment with 400 mg of celecoxib, a cyclooxygenase-2 inhibitor, leads to a significant reduction in the number of colorectal polyps.  相似文献   
147.
Many cognitive psychological, computational, and neuropsychological approaches to the organisation of semantic memory have incorporated the idea that concepts are, at least partly, represented in terms of their fine-grained features. We asked 20 normal volunteers to provide properties of 64 concrete items, drawn from living and nonliving categories, by completing simple sentence stems (e.g., an owl is __, has __, can__). At a later date, the same participants rated the same concepts for prototypicality and familiarity. The features generated were classified as to type of knowledge (sensory, functional, or encyclopaedic), and also quantified with regard to both dominance (the number of participants specifying that property for that concept) and distinctiveness (the proportion of exemplars within a conceptual category of which that feature was considered characteristic). The results demonstrate that rated prototypicality is related to both the familiarity of the concept and its distance from the average of the exemplars within the same category (the category centroid). The feature database was also used to replicate, resolve, and extend a variety of previous observations on the structure of semantic representations. Specifically, the results of our analyses (1) resolve two conflicting claims regarding the relative ratio of sensory to other kinds of attributes in living vs. nonliving concepts; (2) offer new information regarding the types of features-across different domains-that distinguish concepts from their category coordinates; and (3) corroborate some previous claims of higher intercorrelations between features of living things than those of artefacts.  相似文献   
148.
The calcium ionophore A23187(A23) at concentrations exceeding 1 microgram/ml has been shown to be progressively cytotoxic for human blood basophils, neutrophils, lymphocytes, and erythrocytes. Toxicity to basophils was considered to be manifested by the increasing inability of 2-deoxyglucose (2DG) to inhibit histamine release (HR) at increasing concentrations of A23. The toxicity to neutrophils and lymphocytes was demonstrated by decreased lactate production (LP) after incubation with A23 of Ficoll-Hypaque fractions greatly enriched in each respective cell type. Red cells present in dextran-sedimented leukocytes were increasingly susceptible to lysis during washing subsequent to exposure to increasing concentrations of A23. A concentration of 4 microgram A23/ml, which is cytotoxic at 37 degrees C, produced optimal and noncytotoxic HR at 22 degrees C. It was possible to reduce A23 concentrations required for optimal HR by increasing Ca++ from 0.6 to 3 mM.  相似文献   
149.
Previous studies have documented poor recognition memory for faces in patients with semantic dementia. Preserved face recognition memory was found in this study, however, so long as atrophy was confined predominantly to the left temporal lobe. Patients with structural damage to the right temporal lobe were typically impaired, with the status of the hippocampus and parahippocampal gyrus (including the perirhinal cortex) on the right being critical. Two single-case studies of patients with predominantly left temporal lobe pathology confirmed good recognition memory for famous faces, even if semantic knowledge about the celebrities depicted was severely degraded. An effect of semantic knowledge on recognition memory became apparent only when perceptually different photographs of the famous people were used at study and test. These results support the view that new episodic learning typically draws on information from both perceptual and semantic systems.  相似文献   
150.
BACKGROUND: Randomised controlled trials have shown the efficacy of several treatment modalities for lower urinary tract symptoms (LUTS) in selected populations. The effectiveness in daily practice has hardly been investigated, especially in primary care and is dependent on choices between all possible treatment options and best investigated in a comprehensive study, including all treatment modalities (watchful waiting, alpha-blockers, 5-alpha-reductase inhibitors, and surgery). AIM: Assessment of the effectiveness of a comprehensive treatment protocol for LUTS in primary care. DESIGN OF STUDY: Randomised controlled trial. SETTING: Fourteen general practices in the Netherlands. METHOD: Intervention: treatment protocol based on a formalised expert opinion. Control condition: usual care. Study population: 208 subjects with moderate to severe LUTS (IPSS > or =8, median = 13). OUTCOME MEASURES: symptom severity (IPSS [International Prostate Symptom Score]), bother score (Dan-PSS [Danish Prostate Symptom Score]), and maximum urinary flow (Q(max)); incidence of acute urinary retention and urinary tract infections. RESULTS: In the intervention group markedly more subjects used an alpha-blocker at end of follow-up than in the usual care group (24% versus 6%). No significant differences were found between intervention and control group in IPSS, Q(max) or Dan-PSS. CONCLUSION: alpha-blockers and watchful waiting are the most frequent treatment modalities for LUTS in primary care. Our study showed no evidence that a protocol using well-defined indications for all possible treatment modalities based on a formalised expert opinion procedure has added value. Based on our results, we cannot recommend a broadening of the indication for alpha-blockers, which, however, seems to be the current trend.  相似文献   
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