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Revolution in biotechnology made possible to identify those gene errors, which via their encoded proteins (mostly kinase enzymes) are key players in tumor development, growth and progression, and could be considered as molecular targets in tumor diagnosis and therapy. Activity of EGFR (epidermal growth factor receptor), an outstanding representative of the regulatory cell surface receptors, can be inhibited by drugs proved for clinical use. In the past year many groups observed that those lung adenocarcinoma cells, which contain activating mutation in the tyrosine kinase domain of EGFR show remarkable sensitivity to anti-EGFR compounds. The basis of the effective therapy is the identification of the mutations. The clinical advantage of EGFR is an example from the coming age of tumor chemotherapy, when the presence of molecular targets will guide the therapeutic choice.  相似文献   
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Multiple endocrine neoplasia type 1 syndrome is an autosomal dominant disorder characterized by endocrinopathies involving the parathyroid glands, anterior pituitary gland, and pancreas. Also, it may be associated with foregut carcinoid, adrenocortical tumors and non-endocrine tumors. After reviewing the prevalence, genetic background, clinical symptoms, diagnosis and treatment of the disorder, the authors present their genetic screening method used for the detection of mutations of the MEN1 gene (prescreening of polymerase chain reaction amplified exons using temporal temperature gradient gel electrophoresis followed by direct DNA sequencing). Using this method, the authors identified disease-causing MEN1 gene mutations in 9 probands (small deletions in 2 cases, insertion in 2 cases, nonsense mutations in 2 cases and missense mutations in 3 cases). Of the 9 mutations, 4 proved to be novel mutation not reported in the literature. Family screening indicated de novo mutations in 2 probands. In addition to mutations, several sequence polymorphisms were also detected. The authors conclude that one of the major advantages of genetic screening in families with MEN1 syndrome was the identification of family members carrying the mutation who should be regularly screened for disease manifestations and those not carrying the mutation in whom clinical screening is unnecessary. Also, genetic screening may be useful in cases when MEN1 syndrome is suspected, but the clinical manifestations do not fully establish the diagnosis of MEN1 syndrome.  相似文献   
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INTRODUCTION: The authors analyzed the incidence of interstitial lung disease in mixed connective tissue disease. They were seeking an answer to the following problems: the nature of the pathological course of mixed connective tissue disease complicated by and the therapy to be used in interstitial lung disease. PATIENTS AND METHODS: 179 patients were followed up during a period of 15.9 +/- 6.1 years. Interstitial lung disease was diagnosed using high resolution computed tomography. The diagnosis of interstitial lung disease was not obvious in 5 patients thus open lung biopsy was performed, which confirmed common interstitial pneumonitis. The patients were followed-up, and the data of computed tomography and respiratory function tests were detected 6 months, and then 4 years after the acute lung disease complicated by mixed connective tissue disease. RESULTS: Out of the 179 mixed connective tissue disease patients 96 (53.6%) had interstitial lung disease. The onset of interstitial lung disease was the most frequent in the 2-4 years of the disease. Four years after the first appearance of interstitial lung disease severe fibrosis was diagnosed in 24 patients (25%). A honey comb formation in the lung developed only in one patient. For the treatment of interstitial lung disease, corticosteroid treatment had to be combined with cyclophosphamide in 51 cases. In 4 patients (24%), pulmonary arterial hypertension evolved 2-4 years following interstitial lung disease. The high pulmonary arterial pressure decreased using pulsed corticosteroid treatment, cyclophosphamide, prostacyclin analogue, anticoagulants therapy and the 4 patients stay alive. The pulmonary arterial hypertension was caused by obliterative vasculopathy. CONCLUSION: Pulmonary involvement is found in more than half of the patients with mixed connective tissue disease. Early diagnosis of interstitial lung disease is possible by computed tomography. Interstitial lung disease can be treated by the combination of corticosteroids and cyclophosphamide. The authors were the first to detect the coexistence of interstitial lung disease and pulmonary arterial hypertension in mixed connective tissue disease. Subsequent respiratory alterations in these patient necessitate regular patient follow up.  相似文献   
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AIM: To look for the frequency of oesophageal dysfunction using radionuclide oesophageal transit scintigraphy in 145 patients with undifferentiated connective tissue disease (UCTD); to seek the correlation between the clinical/laboratory data and scintigraphic alterations; and to determine predictive value of radionuclide oesophageal transit scintigraphy for evolution to established connective tissue disease (CTD). METHOD: One hundred and forty-five patients with UCTD were examined by 99mTc-DTPA oesophageal transit scintigraphy. The intraoesophageal transport of the radiopharmaceutical was followed and imaged by a gamma camera, a series of 128 x 128 images were stored and evaluated. The correlation between the scintigraphic data and clinical and laboratory parameters was analysed statistically. RESULTS: Unequivocally positive scintigraphy, indicative of motor abnormality was found in 46% of patients (66), 71% (47) of whom were totally asymptomatic. Significant correlation was found between the presence and severity of scintigraphic alterations and antinuclear antibodies, the anti-beta2GPI, IgM, IgG, the aCL antibody positivity, and the skin symptoms. Scintigraphic positivity was significantly more frequent in patients evolving to definitive CTD (P = 0.0178), and abnormal scan predisposed to transition into the definitive CTD (odds ratio, 2.292; CI, 1.610-4.525). Its cumulative positive predictive value was found to be 43% and cumulative negative predictive value 73% with regard to the development of a definitive CTD. CONCLUSION: Our results show that scintigraphic alterations together with clinical and laboratory alterations can help the clinician in the prediction of final outcome.  相似文献   
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OBJECTIVES: Chemically induced mucosal inflammation in animal models is a suitable tool for studying factors in the pathogenesis of inflammatory bowel disease. The aim of this study was to determine whether absence of histamine has an effect on the development of experimental colitis. METHODS: Histamine-deficient, histidine decarboxylase (HDC) knockout Balb/c mice and genetically identical control animals with intact HDC were studied. Colitis was induced by the administration of 2% dextran sodium sulphate in drinking water. Mice were killed after 5 days and disease activity assessed by clinical, histologic, and immunohistologic parameters. Bacterial components of stool were examined. RESULTS: Clinical disease activity was higher in the mice with intact HDC (disease activity index, 2.21) than in the histamine-deficient knock-out mice (1.88). Histologic findings were similar in the two groups. On day 5, the inflammation score of the HDC sufficient group was 5.25 (+/-1.055) and the crypt score was 5.00 (+/-1.128). The scores in the HDC knock-out group were 4.667 (+/- 0.707) and 4.667 (+/- 0.86), respectively. There was a significant difference in the number of interleukin (IL-10)-producing lymphocytes in colon mucosa. Large numbers of IL-10-positive lymphocytes were observed in wild type mice both those with DSS induced colitis and untreated controls. Only sporadic IL-10 positivity was found in histamine-deficient mice. Significant differences were found in the composition of the fecal bacterial flora between the two groups. CONCLUSION: The reduced number of IL-10-positive lymphocytes in the intestinal mucosa of histamine-deficient, histidine decarboxylase knockout mice and the altered fecal bacterial flora in these animals suggest that histamine may play a role in the pathophysiology of inflammation in the colon of normal animals by upregulating local IL-10 production and stimulating a local shift to Th2 response.  相似文献   
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Antineoplastic chemotherapy is associated with nephrotoxic side effects. Data on nephrotoxicity in childhood cancer are scanty, in part because of the difficulties in obtaining reliable markers of glomerular function. We used serum cystatin C (cysC) to assess glomerular function. CysC was compared with serum creatinine concentration (SCr), the endogenous creatinine clearence ( C Cr), and the calculated Counahan formula ( C Counahan) in children with leukemia and solid tumors. CysC was measured by particle-enhanced immunoturbidimetric assay. Serum and urinary creatinine concentrations were determined by the Jaffé method. Samples were obtained from 258 children, including 92 receiving anticancer chemotherapy, 108 long-term survivors, 40 children without any renal disease, and 18 patients with chronic renal insufficiency. CysC of patients on current chemotherapy was assessed both before and after treatment. Significant correlations were found between cysC and SCr and between 1/cysC and C Counahan. CysC increased significantly after cisplatin, methotrexate, cyclophosphamide, ifosfamide, and multimodality treatment. Our results suggest that cysC measurement can be used to characterize glomerular function in children with cancer.  相似文献   
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