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991.
A case of a squamous cell lung carcinoma detected with 99mTc-DPD, 67Ga-citrate and 99mTc-glucoheptonate (GH) is reported. The highest uptake was seen with DPD and the lowest with 67Ga. Emission-computed tomography was very useful in DPD imaging but gave less new information in GH and 67Ga studies in comparison to traditional planar imaging. The patient had been given both irradiation and chemotherapy, which might be the cause of good accumulation of DPD and rather poor accumulation of GH and 67Ga.  相似文献   
992.
Recent clinical evidence indicates a potential for skeletal muscle toxicity after therapy with HMG-CoA reductase inhibitors (HMGRIs) in man. Although the incidence of drug-induced skeletal muscle toxicity is very low (0.1-0.2%) with monotherapy, it may increase following concomitant drug therapy with the immunosuppressant, cyclosporine A (CsA), and possibly with certain other hypolipidemic agents. In the Sprague-Dawley rat, very high, pharmacologically comparable dosages (150-1200 mg/kg/day) of structurally similar HMGRIs (lovastatin, simvastatin, pravastatin and L-647, 318) produced dose-related increases in the incidence and severity of skeletal muscle degeneration. Physical signs included inappetence, decreased activity, loss of body weight, localized alopecia and mortality. To evaluate the interaction between HMGRIs and CsA, a rat model of CsA-induced cholestasis was developed. In this 2-week model, the skeletal muscle toxicity of the HMGRIs was clearly potentiated by CsA (10 mg/kg/day). Doses of HMGRIs which did not produce skeletal muscle toxicity when given alone caused between 75 and 100% incidence of myopathy (very slight to marked skeletal muscle degeneration) when CsA was coadministered. Typical light microscopic changes included myofiber necrosis with interstitial edema and inflammatory infiltration in areas of acute injury. Histochemical characterization of the muscle lesion indicated that type 2B fibers (primarily glycolytic white fibers) were most sensitive to this toxicity but that, with prolonged administration, all fiber types were ultimately affected. Results of pharmacokinetic studies in rats treated with various HMGRIs +/- CsA indicated that coadministration of CsA alters the disposition of these compounds, resulting in increased systemic exposure (e.g., increased area under the plasma drug concentration vs. time curve-AUC) and consequent (up to 13-fold) increases in skeletal muscle drug levels. Evaluation of the potential interaction between the HMGRI, lovastatin and CsA at the level of hepatic microsomal metabolism indicated that CsA did not inhibit the metabolism of lovastatin in isolated microsomes from female rats. In light of the above findings, it appears that HMGRI-induced myopathy is a class effect in the rat, which is potentiated by CsA as the result of altered clearance and resultant increased tissue exposure. Cholestasis associated with CsA and HMGRIs may form the basis for decreased elimination and the resultant elevated systemic exposure. Furthermore, this toxicity is muscle fiber-selective and may be associated with impaired skeletal muscle energy metabolism.  相似文献   
993.
The distribution of cytokeratins Nos. 19 (CK 19), 14, 16 and 17 (CK2-27), and 8 and 18 (CK 60-61) in 96 oral mucosal biopsies taken from women with genital HPV infections were studied by immunohistochemistry, using polyclonal antibody CK 19, as well as monoclonal antibodies CK 2-27 and CK 60-61. White staining of the buccal mucosa after acetic acid application, which recently was shown to be affected mostly by smoking and age, could not be explained by differences in cytokeratin pattern. In HPV DNA-positive biopsies, the staining with CK 19 antibody in the basal cell layer was more intense than in HPV DNA-negative biopsies. The staining with CK 2-27 antibody was seen in 76% and 91% of the basal and superficial layers, respectively, even though these low molecular weight cytokeratins should be found mainly from the basal and parabasal cells. CK 60-61 staining was almost similar to that seen recently in normal genital mucosa. When trying to distinguish oral HPV infections from normal mucosa, CK 2-27 and CK 60-61 stainings were of no diagnostic value. The more efficient expression of CK 19 in HPV DNA-positive samples suggests that viral infection might accelerate the production of low molecular weight cytoskeletal protein. This could be interpreted as evidence that HPV might disturb the keratinocyte differentiation in the basal cells. As a result of the present study, CK 19 staining in oral mucosa needs to be further studied in regard to viral infections, because it may help to better understand the interaction between a virus and a host cell.  相似文献   
994.
20 patients with juvenile periodontitis (JP) were treated with oral hygiene instruction, scaling and root planing, possibly with flap surgery but with no antibiotics. The patients were monitored after 6 to 12 years. Re-examination revealed that no probing depth of 7 mm or more existed any longer, and that sites with probing depth of 4 to 6 mm had decreased from 237 to 46. The bone loss scores had changed from 18% (range 2.0 to 48.1) to 14% (range 0 to 44.4) and the bleeding on probing scores from 39% (range 0 to 100) to 10% (range 0 to 40). Actinobacillus actinomycetemcomitans (A.a.) had neither been cultivated nor serologically tested at the initial examination. At the re-examination, it was found in 2 patients out of 20 at 5 sites. 7 patients, the 2 with positive cultures included, had elevated titers to A.a. strain Y4 in whole or parotid saliva or both. It is concluded that there is a marked improvement in the periodontal condition of these patients, and that good periodontal health in patients with JP can be reached without antibiotics.  相似文献   
995.
Single neurons in culture express a heterogeneity of neurotransmitter receptor subtypes. The study of the effects of neurotransmitters on neuronal function is complicated by this heterogeneity. It would therefore be useful to be able to identify live neurons that express the receptors of interest and then use these neurons for functional studies. We have used quantitative fluorescence microscopy to identify single live striatal neurons that express D1 dopamine receptors. The binding of the fluorescent D1 dopamine receptor antagonist bodipy-SCH 23390 was measured in 2–3-week-old primary striatal cultures derived from fetal rats (embryonic day 18). Binding of bodipy-SCH 23390 to live neurons was displaced by (+)-butaclamol, dopamine or SCH 23390, indicating that it specifically labelled D1 dopamine receptors. However, the fraction of bodipy-SCH 23390 binding that was specific varied substantially among individual neurons indicating heterogeneity of D1 dopamine receptor expression. Interestingly, bodipy-SCH 23390 also specifically labelled discrete spots of receptors on the neuronal processes. This technique should prove useful in the study of the effects of dopaminergic drugs on neuronal function in primary culture.  相似文献   
996.
The purpose of the present investigation was to assess whether different positions of the vaginal measuring device affect the pressure readings during pelvic floor muscle (PFM) contraction. Twelve women with stress urinary incontinence (SUI) participating in a PFM exercise program, volunteered for the study. The diagnosis of SUI was based on urodynamic investigation and pad test. The mean age of the women was 40.9 years (24–50). The women performed three PFM contractions with a vaginal balloon placed in four different positions: 1) against the vaginal vault and in the posterior fornix, 2) in the proximal upper third of the vagina, 3) with the middle of the balloon 3.5 cm from the introitus vagina and 4) with half of the balloon outside the introitus vagina. The results demonstrated significant differences between recordings from the four vaginal positions: position 1, median pressure 5 cm H2O; position 2, 9 cm H2O; position 3, 15 cm H2O; and position 4, 8 cm H2O. It is concluded that the position of the vaginal device affects the results. This may be one important factor which could explain the variability of vaginal pressure recordings during PFM contractions. For most women the highest pressure was recorded in position 3. © 1992 Wiley-Liss, Inc.  相似文献   
997.
Stings from scorpions (Buthus tamulus) produce acute myocarditis and can result in death in children and adults. Acute myocarditis was induced in anaesthetised dogs by intravenous injection of 4 mg/kg venom (Buthus tamulus). Myocarditis was confirmed by ECG. Blood was collected before and 30 minutes after venom treatment and processed for osmotic fragility. An increase in osmotic fragility of red cells in addition to initial hypertension followed by hypotension were observed in venom treated animals. These results suggest that scorpion venom causes autonomic storm and the released catecholamines were responsible for acute myocarditis, changes in the blood pressure and increased osmotic fragility of red cells.  相似文献   
998.
In a central institution for persons with mental retardation, the dental status in 30 adult patients with Down syndrome was compared with that in a carefully selected group of gender-and age-matched mentally retarded patients. This investigation showed an increased frequency of periodontitis in the population with Down syndrome. The caries rate, however, did not differ demonstrably between the groups. Edentulism was more frequent in patients with Down syndrome than in controls, and this fact may substantiate the observation of increased frequency of periodontitis. Caries seems to be less prevalent in institutionalized patients with mental retardation than in the population at large  相似文献   
999.
The COP regimen has been widely used as a second-line treatment for advanced chronic lymphocytic leukemia (CLL). In this retrospective analysis of COP therapy 24 patients with CLL were included. All but two patients had previously been treated with alkylating agents and had become refractory to the therapy. The overall response rate to COP was 25%. Three patients had CR (12.5%), three PR (12.5%), five SD (21%), four PD (17%), and nine patients died (37.5%) during the COP treatments. The cause of death was neutropenic sepsis in all cases. The median duration of responses was 18 months. The median survival of all patients was 9.5 months. The survival of responders was 24.5 and of non-responders only 5.5 months. The COP regimen seems to have low efficacy in the treatment of refractory CLL and the toxicity of this regimen in the late disease phase appears to be unacceptable.  相似文献   
1000.
The study comprises 149 refugees from various countries, reporting exposure to severe traumata, who were referred for psychiatric diagnosis and assessment of suicide risk. The stressors reported comprised both personal experience of and/or forced witnessing of combat atrocities (including explosions or missile impacts in urban areas), imprisonment (including isolation), torture and inflicted pain, sexual violence, witnessing others' suicide, and of summary and/or mock executions. Posttraumatic stress disorder (PTSD) was diagnosed in 79% of all cases, other psychiatric illness in 16% and no mental pathology in 5%. The prevalence of suicidal behavior was significantly greater among refugees with principal PTSD diagnoses than among the remainder. PTSD patients with depression comorbidity reported higher frequency of suicidal thoughts; PTSD nondepressive patients manifested increased frequency of suicide attempts.  相似文献   
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