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991.
Synovial chondromatosis is an uncommon disorder with rare occurrence in the elbow. Case reports in the literature for elbow synovial chondromatosis have described presenting symptoms secondary to peripheral nerve compressions or localized bursitis. We discuss a case of synovial chondromatosis of the elbow that presented as an isolated soft-tissue mass over the radial head-more suggestive of a soft-tissue tumor than of synovial chondromatosis.  相似文献   
992.
BACKGROUND: Transplant-associated coronary artery disease (TxCAD) is the most serious long-term complication after cardiac transplantation. Anti-endothelial antibodies are associated with disease, and one of the major endothelial antigens recognized in the sera of patients has been shown to be the protein filament vimentin. In this study, we investigated whether antivimentin antibodies are associated with TxCAD and whether their presence can be used to identify patients at high risk of developing angiographically detectable TxCAD. METHODS: Up to 5 years after transplantation, 880 sequential sera (7.07+/-1.8 samples/patient) were collected retrospectively from 109 patients; the majority were collected in the first 2 years. Sera were assessed for antivimentin antibodies using ELISA. TxCAD was assessed by annual angiography. RESULTS: Mean titres of antivimentin antibodies, calculated up to 1, 2, and 5 years, were significantly higher in patients who developed TxCAD than those who remained disease free (P<0.0001, P<0.0038, and P<0.0001, respectively). A predictive test based on the first-year mean vimentin titre alone (> or = 120) produced a test with 63% sensitivity and 76% specificity. Inclusion of persistent rejection or high 1-year mean titre (> or = 270) as a risk factor produced a test with 66% sensitivity and 82% specificity. Multivariate analysis of time to occurrence of transplant vasculopathy showed that mean titre at 1 or 2 years was an independent predictor of time until disease in the presence of all other variables. CONCLUSIONS: Antivimentin antibodies are an independent predictor of TxCAD and can be used to identify some of the patients who are at high risk of developing this complication.  相似文献   
993.
BACKGROUND: Since the last British study of the microbial aetiology of community acquired pneumonia (CAP) about 20 years ago, new organisms have been identified (for example, Chlamydia pneumoniae), new antibiotics introduced, and fresh advances made in microbiological techniques. Pathogens implicated in CAP in adults admitted to hospital in the UK using modern and traditional microbiological investigations are described. METHODS: Adults aged 16 years and over admitted to a teaching hospital with CAP over a 12 month period from 4 October 1998 were prospectively studied. Samples of blood, sputum, and urine were collected for microbiological testing by standard culture techniques and new serological and urine antigen detection methods. RESULTS: Of 309 patients admitted with CAP, 267 fulfilled the study criteria; 135 (50.6%) were men and the mean (SD) age was 65.4 (19.6) years. Aetiological agents were identified from 199 (75%) patients (one pathogen in 124 (46%), two in 53 (20%), and three or more in 22 (8%)): Streptococcus pneumoniae 129 (48%), influenza A virus 50 (19%), Chlamydia pneumoniae 35 (13%), Haemophilus influenzae 20 (7%), Mycoplasma pneumoniae 9 (3%), Legionella pneumophilia 9 (3%), other Chlamydia spp 7 (2%), Moraxella catarrhalis 5 (2%), Coxiella burnetii 2 (0.7%), others 8 (3%). Atypical pathogens were less common in patients aged 75 years and over than in younger patients (16% v 27%; OR 0.5, 95% CI 0.3 to 0.9). The 30 day mortality was 14.9%. Mortality risk could be stratified by the presence of four "core" adverse features. Three of 60 patients (5%) infected with an atypical pathogen died. CONCLUSION: S pneumoniae remains the most important pathogen to cover by initial antibiotic therapy in adults of all ages admitted to hospital with CAP. Atypical pathogens are more common in younger patients. They should also be covered in all patients with severe pneumonia and younger patients with non-severe infection.  相似文献   
994.
Sympathetic reinnervation of rat kidney grafts   总被引:3,自引:0,他引:3  
Grisk O  Gröne HJ  Rose HJ  Rettig R 《Transplantation》2001,72(6):1153-1155
BACKGROUND: Reinnervation occurs in many transplanted tissues and organs. Sympathetic reinnervation in rat kidney grafts was investigated. METHODS: Rats were syngeneically transplanted with a kidney and bilaterally nephrectomized. Reinnervation was assessed by immunohistochemical staining for neuron-specific protein gene product 9.5 (PGP 9.5) and by tissue norepinephrine measurements in grafts removed 1.5 (n=6), 3 (n=7), 6 (n=8), and 9 (n=7) months after transplantation. RESULTS: PGP 9.5-positive neural structures were significantly reduced in grafts removed 1.5 and 3 months after transplantation compared with native kidneys with slightly increased numbers at 6 and 9 months after transplantation. Median transplant norepinephrine concentrations remained at approximately 3% compared with native kidneys until 9 months after transplantation. CONCLUSIONS: In transplanted rat kidneys, some reinnervation occurs in the hilum within 9 months after transplantation. This is not accompanied by a significant recovery of norepinephrine concentration in renal tissue indicating persistent sympathetic denervation.  相似文献   
995.
OBJECTIVES: Rainfall and runoff have been implicated in site-specific waterborne disease outbreaks. Because upward trends in heavy precipitation in the United States are projected to increase with climate change, this study sought to quantify the relationship between precipitation and disease outbreaks. METHODS: The US Environmental Protection Agency waterborne disease database, totaling 548 reported outbreaks from 1948 through 1994, and precipitation data of the National Climatic Data Center were used to analyze the relationship between precipitation and waterborne diseases. Analyses were at the watershed level, stratified by groundwater and surface water contamination and controlled for effects due to season and hydrologic region. A Monte Carlo version of the Fisher exact test was used to test for statistical significance. RESULTS: Fifty-one percent of waterborne disease outbreaks were preceded by precipitation events above the 90th percentile (P = .002), and 68% by events above the 80th percentile (P = .001). Outbreaks due to surface water contamination showed the strongest association with extreme precipitation during the month of the outbreak; a 2-month lag applied to groundwater contamination events. CONCLUSIONS: The statistically significant association found between rainfall and disease in the United States is important for water managers, public health officials, and risk assessors of future climate change.  相似文献   
996.
997.
Virus-like particles (VLPs) of the high-risk human papillomavirus (HPV) types 16, 18, 31, 33, and 45 were used as antigen in enzyme-linked immunosorbent assay (ELISA) to determine the prevalence of serum IgG in a group of San people originally from Namibia, now residing in South Africa. The San children had low seroprevalence to all VLP types, but 26/115 (22.6%) of the children were seropositive to at least 1 VLP type. Among the adults, seroprevalence was significantly higher. The seroprevalence of antibodies in 101 San women to VLP-16 was 16.8%, VLP-18 18.8%, VLP-31 12.9%, VLP-33 17.8%, and VLP-45 22.8%. Five of the 11 men were seropositive: 2 for VLP-31, 1 for VLP-18, 1 for VLP-33, and 1 for VLP-45. Seroreactivity appeared to be type specific, except possibly to VLP-18 and -45. Of the adults, 50.5% were seropositive to at least 1 VLP type and 24.8% were seropositive to >1 VLP type. From this study, it is concluded that the San people are exposed to HPV-16, -18, -31, -33, and -45, with antibodies to VLP-45 being the most prevalent.  相似文献   
998.
OBJECTIVES: Fallopian tube carcinoma is similar to ovarian and peritoneal carcinoma with respect to histology, response to chemotherapy, and prognosis. BRCA germline mutations have been commonly reported in ovarian and peritoneal carcinoma but rarely in other gynecologic cancers. METHODS: A patient with fallopian tube carcinoma and a family history of ovarian carcinoma underwent genetic counseling and BRCA testing as did her daughter. RESULTS: The patient and her daughter were found to have a germline BRCA2 mutation. CONCLUSION: Like a family history of ovarian or peritoneal carcinoma, the occurrence of fallopian tube cancer should alert the clinician to the possibility of an abnormality in the breast cancer susceptibility 1 or 2 genes.  相似文献   
999.
BACKGROUND: As suggested by preclinical trials, prolonged administration of topotecan, a reversible inhibitor of topoisomerase-I, may have a therapeutic advantage. Following a phase I trial of weekly 72-h topotecan infusion, we performed a phase II trial utilizing this schedule in ovarian carcinoma. METHODS: Eligibility included platinum-/paclitaxel-resistant ovarian carcinoma, measurable disease, and adequate hematologic, renal, and hepatic function. A dose of 2.0 mg/m(2) of topotecan was administered as a 72-h infusion weekly via an ambulatory pump. Plasma topotecan concentrations were determined prior to and at the completion of each weekly course. RESULTS: Twenty-four patients were entered and 23 patients were evaluable for toxicity and response. Two hundred eighteen weekly courses of therapy were administered (median 7 weeks, range 4-46 weeks). Toxicity was mild with grade 3 leukopenia, neutropenia, and anemia occurring in 13, 13, and 17% of patients, respectively. Two of 23 patients (9.1%) (CI 1-28%) had partial responses of 2 and 3 months' duration and 6 had stable disease. Steady state plasma topotecan lactone concentrations were a median of 1.2 ng/ml (range 0.4-8.00 ng/ml) following the first week of infusion. Steady state topotecan lactone concentrations after the first week of infusion were highest in 2 patients with partial responses. Mean steady state plasma topotecan lactone concentrations after the first week of infusion were 4.6, 2.0, and 1.3 ng/ml for partial response, stable disease, and progressive disease, respectively. An analysis of variance of steady state plasma topotecan concentrations after the first week of infusion over all administered cycles demonstrated a significant difference in steady state plasma topotecan lactone concentrations between patients with partial response and stable disease and between partial response and no response (significant at the 0.05 level after adjustment for multiple comparisons). Controlling for cycle number, steady state topotecan lactone concentrations are significantly greater for patients with responding or stable disease than those with progressive disease (P = 0.0003) and have a lower bound of > or = 1.9 ng/ml (95% confidence level). CONCLUSION: Steady state topotecan lactone concentrations are associated with responding or stable disease in platinum- and paclitaxel-resistant ovarian cancer. Steady state topotecan concentrations could potentially be utilized to modify tumor exposure and response.  相似文献   
1000.
Experimental autoimmune thyroiditis (EAT), produced in the mouse by immunization with murine thyroglobulin plus complete Freund's adjuvant, represents a valuable model for studying the pathogenesis of human chronic (Hashimoto's) thyroiditis. A major issue requiring clarification is the difference between benign autoimmunity, characterized solely by production of autoantibodies to thyroglobulin, and pathogenic autoimmunity where injury occurs to the thyroid cells. In this article, we describe the role of two key cytokines, IL12 and IFNgamma, in modifying the pathogenic immune response. EAT, defined by cellular infiltration of the thyroid and the development of thyroglobulin-specific autoantibodies, is a dynamic process. Consequently, a cytokine may exert a different effect at different times during the disease process. For purposes of discussion, we propose that there are three stages in the development of EAT: priming; initiation; and progression. Administration of anti-IL12 during the priming stage and initiation dramatically decreases disease and lowers autoantibody levels. In contrast, injection of recombinant IL12 after disease was established significantly decreases the severity of disease and reduces autoantibody levels. Unlike IL-12, IFNgamma was not essential for the priming of EAT. However, the severity of disease in the anti-IFNgamma-treated initiation- and progression-treated animals was higher than in controls, implying a regulatory role for IFNgamma. These findings emphasize that EAT involves a complex array of pathogenic mechanisms. The balance of cytokines produced during the early phase of the autoimmune reaction probably determines the progression from a harmless autoimmune response to autoimmune disease.  相似文献   
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