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971.
972.
973.
Electromyography is frequently used to measure the activity of masticatory muscles. It requires the precise setting of the electrodes, which demands the accurate location of the muscle to be evaluated. The purpose of this study was to investigate the accuracy of an external method to locate the buccinator muscle. Fifteen human cadavers were evaluated and planes were determined on the face using anatomic landmarks. An angle (a) was obtained at the intersection of these planes on the central point of buccinator muscle and measured with a protractor. The value of the angle allows locating the central point of buccinator muscle based on anatomic landmarks on the face. Statistical analysis of the collected data indicated an angle of 90 masculine with 95% reliability, thus proving the efficacy of the proposed method.  相似文献   
974.
OBJECTIVES: To evaluate the efficacy of a multistep cleaning method using a cleaner and a chemical disinfectant on blood-contaminated angiographic catheters and spinal needles intended to be sterilized by hydrogen peroxide gas plasma. METHOD: A mixture of radiopaque iodine contrast, bovine blood (plus ethylenediaminetetraacetic acid), and a suspension of Bacillus subtilis spores was used to simulate catheterization and needle use. The mixture was a 1:1 proportion of contrast and blood, inoculated so that there was a final concentration of B subtilis spores of 1.0x10(6) colony-forming units (CFU)/mL. The inoculated devices were cleaned using a hydrogen peroxide solution at a concentration of 1.5+/-0.5 percent by weight, followed by distilled water with enzymatic detergent. After drying, the devices were sterilized with hydrogen peroxide gas plasma. RESULTS: The initial B subtilis spore concentration inoculated into catheters and needles varied from 2.12x10(4) to 2.74x10(7) CFU/mL. The residual load of B. subtilis spores after cleaning varied from zero (no count) to a maximum of 200 CFU/device. The multistep cleaning procedure was responsible for an average 5log10 reduction of B. subtilis spores in the catheter and needle lumens. CONCLUSIONS: The hydrogen peroxide and enzymatic detergent aqueous solutions were shown to be efficacious when used as part of a multistep cleaning method. The low level of microbial contamination prior to sterilization with hydrogen peroxide gas plasma assured that the intended sterility assurance level was reached.  相似文献   
975.
We investigated the influence of CD4+ T lymphocytes, CD8+ T lymphocytes, and B lymphocytes on the efficacy of posaconazole (POS) and the reference drug benznidazole (BZ) during treatment of acute Trypanosoma cruzi infection in a murine model. Wild-type mice infected with T. cruzi and treated with POS or BZ presented no parasitemia, 100% survival, and 86 to 89% cure rates, defined as the percentages of animals with negative hemocultures at the end of the observation period. CD4+-T-lymphocyte-knockout (KO) mice infected with T. cruzi and treated with BZ or POS controlled parasitemia during treatment, although circulating parasites reappeared after drug pressure cessation, leading to only a 6% survival rate and no cure. CD8+-T-lymphocyte-KO mice infected with T. cruzi and treated with POS or BZ had intermediate results, displaying discrete parasitemia after the treatment was ended, 81 and 86% survival, and cure rates of 31 and 66%, respectively. B-lymphocyte-KO mice infected with T. cruzi and treated with BZ relapsed with parasitemia 1 week after the end of treatment and had a 67% survival rate and only a 22% cure rate. In contrast, the activity of POS was much less affected in these animals, with permanent suppression of parasitemia, 100% survival, and a 71% cure rate. Our results demonstrate that abrogation of different lymphocytes’ activities has distinct effects on the efficacy of POS and BZ in this experimental model, probably reflecting different parasite stages preferentially targeted by the two drugs and distinct cooperation patterns with the host immune system.  相似文献   
976.
Considering that mycobacterial heat-shock protein 65 (hsp65) gene transfer can elicit a profound antitumoral effect, this study aimed to establish the safety, maximum-tolerated dose (MTD) and preliminary efficacy of DNA-hsp65 immunotherapy in patients with advanced head and neck squamous cell carcinoma (HNSCC). For this purpose, 21 patients with unresectable and recurrent HNSCC were studied. Each patient received three ultrasound-guided injections at 21-day intervals of: 150, 600 or 400 microg of DNA-hsp65. Toxicity was graded according to CTCAE directions. Tumor volume was measured before and after treatment using computed tomography scan. The evaluation included tumor mass variation, delayed-type hypersensitivity response and spontaneous peripheral blood mononuclear cell proliferation before and after treatment. The MTD was 400 microg per dose. DNA-hsp65 immunotherapy was well tolerated with moderate pain, edema and infections as the most frequent adverse effects. None of the patients showed clinical or laboratory alterations compatible with autoimmune reactions. Partial response was observed in 4 out of 14 patients who completed treatment, 2 of which are still alive more than 3 years after the completion of the trial. Therefore, DNA-hsp65 immunotherapy is a feasible and safe approach at the dose of 400 microg per injection in patients with HNSCC refractory to standard treatment. Further studies in a larger number of patients are needed to confirm the efficacy of this novel strategy.  相似文献   
977.
Cutaneous leishmaniasis (CL) is an important public health issue worldwide. The control of Leishmania infection depends on cellular immune mechanisms, and the inflammatory response may contribute to pathogenesis. A beneficial role of CD8+ T lymphocytes has been proposed; nevertheless, other studies suggest a cytotoxic role of CD8+ T lymphocytes involved in tissue damage, showing controversial role of these cells. The goal of the current study was to understand the immunopathology of CL and determine the profile of cytotoxic cells – such as CD4+ T, natural killer and natural killer T cells – that might be involved in triggering immunological mechanisms, and may lead to cure or disease progression. The frequencies of cytotoxic cell populations in peripheral blood, obtained from patients with active disease, during treatment and after clinical healing, were assessed by flow cytometry. Cytotoxicity could not be related to a deleterious role in Leishmania braziliensis infection, as patients with active CL showed similar percentages of degranulation to healthy individuals (HI). Cured patients exhibited a lower percentage of degranulating cells, which may be due to a downregulation of the immune response. The understanding of the immunopathological mechanisms involved in CL and the commitment of cytotoxic cells enables improvements in therapeutic strategies.  相似文献   
978.
Multilayered coatings composed of mixtures of hydroxyapatite (HA) and P(2)O(5)-based bioactive glasses offer potential clinical benefits in orthopedic and dental surgery. In this study double-layer plasma-sprayed coatings were prepared and the biological response evaluated in tissue culture using two human osteosarcoma cell lines, MG63 and HOS TE85 (HOS). The cells were cultured on the materials and the effects on cell growth were determined using a spectrophometric assay of a mitochondrial enzyme that is active in viable cells. While none of the materials influenced the growth of the MG63 cells, the HOS cells appeared to undergo less proliferation on all the HA materials. Flow cytometry analysis was carried out using rabbit antibodies against osteonectin, osteopontin, bone sialoprotein, fibronectin, and collagen type I to measure the effects of the materials on key cellular functions. The results showed that the materials downregulated the expression of these extracellular matrix antigens by MG63 cells whereas they had less effect on the HOS cells compared to the same cells incubated on a plastic surface. Notably, with both cell lines the composite with the higher percentage of glass restored the production of connective tissue proteins to levels that were more similar to those present in the control cells.  相似文献   
979.
AIM To assess lactase gene(LCT)-13910CT polymorphisms in Brazilian non-alcoholic fatty liver disease(NAFLD) and nonalcoholic steatohepatitis(NASH) patients in comparison with healthy controls.METHODS This was a transverse observational clinical study with NAFLD patients who were followed at the Hepatology Outpatient Unit of the Hospital das Clínicas, S?o Paulo, Brazil. The polymorphism of lactase non-persistence/lactase persistence(LCT-13910CT) was examined by PCR-restriction fragment length polymorphism technique in 102 liver biopsy-proven NAFLD patients(steatosis in 9 and NASH in 93) and compared to those of 501 unrelated healthy volunteers. Anthropometric, clinical, biochemical and liver histology data were analyzed. Continuous variables were compared using the t or Mann-Whitney tests, and categorical data were compared with the Fisher's exact test. Univariate logistic regression and multivariate logistic regression adjusted for gender and age were performed.RESULTS No differences in the LCT-13910 genotype frequencies were noted between the NAFLD patients(66.67% of the patients with steatosis were CC, 33.33% were CT, and none were TT; 55.91% of the patients with NASH were CC, 39.78% were CT, and 4.3% were TT; P = 0.941) and the healthy controls(59.12% were CC, 35.67% were CT, and 5.21% were TT) or between the steatosis and NASH patients. That is, the distribution of the lactase non-persistence/lactase persistence polymorphism(LCT-13910CT) in the patients with NAFLD was equal to that in the general population. In the NASH patients, the univariate analysis revealed that the lactase nonpersistence(low lactase activity or hypolactasia) phenotype was associated with higher insulin levels(23.47 ± 15.94 μU/m L vs 15.8 ± 8.33 μU/m L, P = 0.027) and a higher frequency of insulin resistance(91.84% vs 72.22%, P = 0.02) compared with the lactase persistence phenotype. There were no associations between the LCT genotypes and diabetes(P = 0.651), dyslipidaemia(P = 0.328), hypertension(P = 0.507) or liver histology in these patients. Moreover, in the NASH patients, hypolactasia was an independent risk factor for insulin resistance even after adjusting for gender and age [OR = 5.0(95%CI: 1.35-20; P = 0.017)].CONCLUSION The LCT-13910 genotype distribution in Brazilian NAFLD patients was the same as that of the general population, but hypolactasia increased the risk of insulin resistance in the NASH patients.  相似文献   
980.
Non-verbal pain assessment scales are useful tools for pain evaluation in persons with communication disorders and moderate–severe dementia. The Doloplus® was one of the first scales to be developed and validated as a pain assessment tool in older adults with dementia. This study aims at evaluating the translation of the Doloplus® scale in five languages, as regards test–retest and inter-rater reliability. Results show that both tests are good or excellent for the English, Italian, Portuguese and Spanish versions and moderate for the Dutch version. These results bring a unique opportunity to include the translated Doloplus® scale in daily assessment of elderly persons with communication disorders, and future studies should focus on enriching the validation of the scale in each language.  相似文献   
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