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81.
This study proposed a novel ventriculoamniotic shunt device for foetal aqueductal stenosis treatment fabricated with 3Fr or 4Fr size catheters that have a longitudinal bending stiffness with kink resistance, sufficient luminal area for cerebrospinal fluid drainage and capacity for valve integration. Computational flow dynamics studies were carried out to optimise the device design, including size of the lumen and length of the device. An in vitro pressure and flow rate measurement test circuit was constructed to assess the high pressure relieving functionality of draining cerebrospinal fluid from foetal brain. Additionally, a resistance force measurement test platform was built to quantitatively evaluate the anchor performance of various geometric designs. The valve functionality was qualitatively evaluated through the visualisation of the flow patterns in the amniotic sac with injected red coloured fluid under stereomicroscopy. These in vitro results demonstrate the feasibility of the ventriculoamniotic shunt device designed for placement in the foetal brain.  相似文献   
82.
Growing evidence substantiates the role of the insulin-like growth factor I (IGF-I) system in breast tumorigenesis. Retinoids have been shown to affect the IGF system in several experimental models. We extended our previous data on plasma IGF-I modulation by the synthetic retinoid fenretinide (4-HPR) and investigated the effect of the retinoid on plasma IGF binding protein (BP)-3, the major protein binding IGFs. IGF-I and IGFBP-3 were measured on plasma samples obtained at randomization and after an interval of approximately 1 year, from 39 and 33 stage I breast cancer patients assigned to receive 4-HPR, and from 39 and 34 untreated controls, respectively. There was a significant decrease in plasma IGF-I after 4-HPR administration, whereas no significant change was observed in controls. The effect of 4-HPR on IGF-I levels was modified by menopausal status, inasmuch as the decrease in IGF-I was particularly pronounced in pre-menopausal women, whereas the reverse was observed in untreated controls. By contrast, treatment induced an increase of IGFBP-3 with respect to controls. As a result of this dual effect, the bioavailability of IGF-I for interaction with receptors at target levels further decreased in pre-menopausal 4-HPR-treated patients compared with controls, suggesting that retinoid administration may result in lower concentrations of biologically active IGF-I. Our findings may have important implications for the clinical preventive activity of this retinoid. Int. J. Cancer 76:787–790, 1998.© 1998 Wiley-Liss, Inc.  相似文献   
83.
Cerebral cavernous malformations (CCMs) are vascular lesions of the CNS characterized by abnormally enlarged capillary cavities. CCMs can occur as sporadic or familial autosomal dominant form. Familial cases are associated with mutations in CCM1[K-Rev interaction trapped 1 (KRIT1)], CCM2 (MGC4607) and CCM3 (PDCD10) genes. In this study, a three-gene mutation screening was performed by direct exon sequencing, in a cohort of 95 Italian patients either sporadic or familial, as well as on their at-risk relatives. Sixteen mutations in 16 unrelated CCM patients were identified,nine mutations are novel: c.413T > C; c.601C > T; c.846 + 2T > G; c.1254delA; c.1255-4delGTA; c.1682-1683 delTA in CCM1; c.48A > G; c.82-83dupAG in CCM2; and c.395 + 1G > A in CCM3 genes [corrected].The samples, negative to direct exon sequencing, were investigated by MLPA to search for intragenic deletions or duplications. One deletion in CCM1 exon 18 was detected in a sporadic patient. Among familial cases 67% had a mutation in CCM1, 5.5% in CCM2, and 5.5% in CCM3, whereas in the remaining 22% no mutations were detected, suggesting the existence of either undetectable mutations or other CCM genes. This study represents the first extensive research program for a comprehensive molecular screening of the three known genes in an Italian cohort of CCM patients and their at-risk relatives.  相似文献   
84.
85.
Hepatocellular carcinoma (HCC) is the most common liver cancer, accounting for 90% of primary liver cancers. In the last decade it has become one of the most frequently occurring tumors worldwide and is also considered to be the most lethal of the cancer systems, accounting for approximately one third of all malignancies. Although the clinical diagnosis and management of early-stage HCC has improved significantly, HCC prognosis is still extremely poor. Furthermore, advanced HCC is a highly aggressive tumor with a poor or no response to common therapies. Therefore, new effective and well-tolerated therapy strategies are urgently needed. Targeted therapies have entered the field of anti-neoplastic treatment and are being used on their own or in combination with conventional chemotherapy drugs. Molecular-targeted therapy holds great promise in the treatment of HCC. A new therapeutic opportunity for advanced HCC is the use of sorafenib (Nexavar). On the basis of the recent large randomized phase III study, the Sorafenib HCC Assessment Randomized Protocol (SHARP), sorafenib has been approved by the FDA for the treatment of advanced HCC. Sorafenib showed to be able to significantly increase survival in patients with advanced HCC, establishing a new standard of care. Despite this promising breakthrough, patients with HCC still have a dismal prognosis, as it is currently the major cause of death in cirrhotic patients. Nevertheless, the successful results of the SHARP trial underscore the need for a comprehensive understanding of the molecular pathogenesis of this devastating disease. In this review we summarize the most important studies on the signaling pathways implicated in the pathogenesis of HCC, as well as the newest emerging drugs and their potential use in HCC management.  相似文献   
86.
Available evidence suggests that vascular endothelial growth factor (VEGF) a potent regulator of vasculogenesis and tumor angiogenesis may be a predictor of recurrence in breast cancer patients. We sought to determine whether VEGF serum levels (VEGF-A, VEGF-C and VEGF-D) in 377 patients with malignant and benign breast tumors differ and whether there is association between vascular growth factors, clinicopathologic features and prognosis. There was no significant difference in investigated circulating angiogenic markers between patients with malignant and non malignant lesions. We found strong correlation between VEGF-A and VEGF-D and between VEGF- C and VEGF-D. Besides serum VEGF-D levels and estrogen receptor (ER) expressions no other correlations between VEGF and clinicopathologic variables were observed. However, elevated VEGF-A and VEGF-C concentrations were associated with increased number of erythrocytes, leukocytes and platelets. In Cox model values of angiogenic serum markers and recognized prognostic markers in breast cancer, VEGF-C turned out as independent prognostic factor. Our study is the first analysis showing correlation between serum concentrations of three angiogenic factors: VEGF-A, VEGF-C, VEGF-D. Associations between angiogenic cytokines and number of blood cells may be due to release of VEGF from platelets and leucocytes. Prognostic role of VEGF is still uncertain, though VEGF-C has a potential to serve as a prognostic marker.  相似文献   
87.
AIM To assess the etiology of chronic liver diseases(CLD) from 1998 to 2014 at the outpatient clinic of Gastroenterology of the main hospital in Northwest of Italy among those dedicated to hepatology.METHODS A random sample of charts of patients referred to for increased liver enzymes between January 1998 and December 2006, and between January 2012 and December 2014 were reviewed. Etiology search included testing for hepatitis B virus(HBV), hepatitis C virus(HCV), autoimmune hepatitis, primary biliary cirrhosis, Wilson's disease and hereditary hemocromatosis. A risky alcohol consumption was also considered. Nonalcoholic fatty liver disease(NAFLD) was diagnosed in patients with histological and/or ultrasound evidence of steatosis/steatohepatitis, and without other causes of CLD.RESULTS The number of patients included was 1163. Of them, 528(45%) had positivity for HCV and 85(7%) for HBV. Among the virus-free patients, 417(36%) had metabolic disorders whereas the remaining had history of alcohol abuse, less prevalent causes of CLD or concomitant conditions. In comparison to 1998-2000(41%), a reduction of HCV alone-related cases was detected during the periods 2001-2003(35%, OR = 0.75, 95%CI: 0.53-1.06), 2004-2006(33%, OR = 0.70, 95%CI: 0.50-0.97) and 2012-2014(31%, OR = 0.64, 95%CI: 0.46-0.91). On the contrary, in comparison to 1998-2000(31%), metabolic-alone disorders increased in the period 2004-2006(39%, OR = 1.37, 95%CI: 0.99-1.91) and 2012-2014(41%, OR = 1.53, 95%CI: 1.09-2.16). The other etiologies remained stable. The increase of incidence of metabolic-alone etiology during the period 2004-2006 and 2012-2014 tended to be higher in older patients(≥ 50 years) compared to younger(P = 0.058).CONCLUSION In the Northwest of Italy, during this study period, the prevalence of HCV infection decreased notably whereas that of NAFLD increased.  相似文献   
88.
89.
Concentrations of 210Pb and 210Po in air, drinking water, foodstuffs, and human tissues are reported. The main route of 210Pb and 210Po intake in the human body is ingestion with foodstuffs. The absorption coefficient of 210Po into the blood from the digestive tract was estimated to be 35%. The highest concentration of 210Pb and 210Po in the body was observed in the skeleton and hair. The body burden of humans was 773 pCi of 210Pb and 513 pCi of 210Po. Excretion of these radionuclides from the body in urine was 14 to 15 times less than in feces. The calculated annual radiation doses of 710Po in the bone, liver, and kidneys were 2.1 to 5.0 millirad/yr, and in other soft tissues, 0.3 to 0.9 millirad/yr.  相似文献   
90.
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