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Bullous melanoma represents a rare variant of melanoma, especially in patients without underlying bullous cutaneous disease. Few cases have been described in the literature, including cases of melanoma in patients with bullous epidermolysis or Hailey-Hailey disease. The histopathological diagnosis of bullous melanoma does not show any difficulties, except for the measurement of the Breslow index. The rarity of this case, the dilemma of how to measure the Breslow index and the importance of an early diagnosis motivated this report.  相似文献   
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BACKGROUND: Increased serum gamma-glutamyl transferase (GGT) levels are frequently observed in chronic hepatitis C virus (HCV) infection. However, the significance of this finding remains unclear. The purpose of the present paper was to assess the relationship between GGT levels and clinical, biochemical and histological features in chronic HCV-infected carriers. METHODS: Patients with a liver biopsy presenting anti-HCV and HCV-RNA were evaluated. Age, gender, risk factors of transmission, serum alanine aminotransferase (ALT), GGT and alkaline phosphatase (ALP) levels and histological features were assessed in all. Data were analyzed statistically by the chi2 test and multivariate logistic regression analysis. RESULTS: Among 201 patients studied, elevated GGT levels and bile duct damage were observed in 48% and 35% of them, respectively. No association was seen between GGT level and bile duct damage or between GGT level and hepatic steatosis. Initially, age >40 years (P=0.007), elevated ALT (P=0.01), grading of inflammatory activity (P=0.004) and staging of fibrosis (P<0.001) were found to be associated with elevated GGT levels. After multivariate regression analysis, histology grading 3 and 4 inflammation activity (P=0.01) and staging 3 and 4 fibrosis (P=0.01) remained independently associated with elevated GGT level. CONCLUSIONS: A significant number of patients with chronic HCV infection had elevated serum GGT levels. Furthermore, this enzyme seemed to be useful as an indirect marker of more advanced liver disease in chronic hepatitis C.  相似文献   
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Human and rhesus monkey platelets secrete at least two antiheparin proteins: platelet factor 4 (PF4) and low affinity platelet factor 4 (LA-PF4). Neither of these proteins showed species-related antigenic differences. As determined by radioimmunoassay, the levels of PF4 and LA-PF4 antigen per 10(9) monkey platelets amounted to 10.7 and 20.3 microgram, respectively. One milliliter of monkey plasma prepared from blood collected into an anticoagulant composed of EDTA, prostaglandin E1, and theophylline solution contained 22.4 ng LA-PF4 and 8.0 ng PF4. Concentrations of these two platelet-specific proteins in monkeys closely resembled levels found in human platelets and plasma. Infusion of prostacyclin (PGI2) (100 or 300 ng/kg/min) into monkeys for 15 min resulted in a significant decrease of plasma levels of LA-PF4 antigen and of PF4 by 40%--60% (p < 0.0001). This decrease was related to the inhibitory effect of PGI2 on the secretion of platelets stimulated by a catheter or by venipuncture. Longer infusion of PGI2 did not produce further significant change. The supernate obtained after aggregation of human platelets stimulated by thrombin was injected into monkeys receiving PGI2 infusion. The disappearance of LA-PF4 antigen in monkey plasma followed a biphasic exponential curve with half-lives for the fast and slow components of 8.4 and 63 min. PF4 disappeared faster but followed the same pattern (half-lives for the fast and slow component of 2.1 and 70 min). Analysis of the experimental data suggests that the low levels of secreted platelet proteins in monkey plasma are related to their minimal in vivo release and to their rapid clearance.  相似文献   
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Achondroplasia is a rare genetic disorder resulting in short‐limb skeletal dysplasia. We present the largest European population‐based epidemiological study to date using data provided by the European Surveillance of Congenital Anomalies (EUROCAT) network. All cases of achondroplasia notified to 28 EUROCAT registries (1991–2015) were included in the study. Prevalence, birth outcomes, prenatal diagnosis, associated anomalies, and the impact of paternal and maternal age on de novo achondroplasia were presented. The study population consisted of 434 achondroplasia cases with a prevalence of 3.72 per 100,000 births (95%CIs: 3.14–4.39). There were 350 live births, 82 terminations of pregnancy after prenatal diagnosis, and two fetal deaths. The prenatal detection rate was significantly higher in recent years (71% in 2011–2015 vs. 36% in 1991–1995). Major associated congenital anomalies were present in 10% of cases. About 20% of cases were familial. After adjusting for maternal age, fathers >34 years had a significantly higher risk of having infants with de novo achondroplasia than younger fathers. Prevalence was stable over time, but regional differences were observed. All pregnancy outcomes were included in the prevalence estimate with 80.6% being live born. The study confirmed the increased risk for older fathers of having infants with de novo achondroplasia.  相似文献   
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The evolving phases of acute appendicitis were studied experimentally. Sixty female rabbits (Oryctogalus cuniculus) of New Zealand lineage weighing about 2510 to 3040 g were divided in two groups: a control group and experimental group. The experimental group was divided into three subgroups for observation after 12, 24 and 48 hours of the operation, that consisted on a 4-0 polypropylene circular suture at 8 cm from the distal part of the cecal appendix. The control group was sham operated. The macroscopic exam (increase of the appendix volume, necrosis, perfuration, adherence and secretion in the abdominal cavity) and the microscopic finding showed a progression in the anatomopathological alterations. There was a close relationship between the histopathological findings and time after the appendiceal obstruction. We conclude that the method causes acute appendicitis and that the anathomo pathological alterations depends on the time elapsed between the operation and the postoperation findings.  相似文献   
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Apoptosis,PCNA and p53 in hepatocellular carcinoma   总被引:16,自引:0,他引:16  
BACKGROUND/AIMS: The regulation of cell number is present in normal tissues but is lost in malignant neoplasms. The real meaning of these alterations is not well known. Apoptosis is the programmed cell death. p53, a tumor suppressor gene, has an important function in DNA repair and in regulation of apoptosis. Mutations of p53 were described in malignant tumors and can be the cause of the alterations of this balance. Proliferating cell nuclear antigen is an auxiliary protein present during G1-late phase and S phase. The aim of this study was to compare cell proliferation, apoptosis and expression of p53 in hepatocellular carcinoma. METHODOLOGY: Fifteen patients with hepatocellular carcinoma were included. Ten patients were men. The mean age of the patients was 55.53 years old. Cirrhosis was positive in nine patients, 5 were HBsAg positive and none were anti-HCV positive. The mean level of AST and ALT were respectively, 62.79 and 50.64. Formalin-fixed and paraffin-embedded tissues from these patients were examined retrospectively. Apoptosis were measured by counting the number of apoptotic bodies in 500 tumoral cells. The expression of p53 oncogene and the PCNA were determined by immunohistochemical method, using avidin-biotin method (DAKO). The p53 were considered positive when the number of positive nuclei was more than 5% of the tumoral cells. The proliferative activity was determined by proliferating cell nuclear antigen labeling index. RESULTS: The proliferating cell nuclear antigen-labeling index ranged from 0.48 and 0.95 (mean: 0.82). The p53 was positive in five patients. The number of apoptotic bodies counted ranged from 0 to 15 (mean: 4.20). There were no differences among p53 and the mean levels of proliferating cell nuclear antigen labeling index or p53 and the number of apoptotic bodies. CONCLUSIONS: A high index of proliferation has been shown in the patients studied. Positivity of p53 was seen in less than a half of the patients (35.71%). The index of apoptotic bodies observed was very low. Our results suggest that high-grade proliferation is not associated with increase of apoptosis in hepatocellular carcinoma.  相似文献   
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