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71.
Repairing large calvarial bone defects remains a challenging task. Previously, it was discovered that that miR‐148b, when acting in concert with bone morphogenetic protein 2 (BMP‐2), enhanced the osteogenesis of human adipose‐derived stem cells (hASCs) and improved calvarial bone healing in nude mice. However, the molecular target of miR‐148b remained elusive. Here it is revealed that miR‐148b directly targets NOG, whose gene product (noggin) is an antagonist to BMPs and negatively regulates BMP‐induced osteogenic differentiation and bone formation. A new Cre/loxP‐based baculovirus system was employed to drive prolonged BMP‐2 and miR‐148b overexpression in hASCs, wherein the BMP‐2 overexpression induced noggin expression but the concurrent miR‐148b expression downregulated noggin, thus relieving the negative regulatory loop and ameliorating hASC osteogenesis without hindering hASC proliferation or triggering appreciable cytotoxicity. Implantation of the engineered hASCs coexpressing BMP‐2 and miR‐148b into nude mice enabled substantial repair of critical‐size calvarial bone defects (4 mm diameter) at 12 weeks post‐transplantation, filling 83% of the defect area, 75% of bone volume and restoring the bone density to 89% of the original bone density. Such superior healing effects indicate the potential of the Cre/loxP‐based baculovirus‐mediated BMP‐2/miR‐148b expression for calvarial bone repair. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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Females and males are different in brain and behavior. These sex differences occur early during development due to a combination of genetic and hormonal factors and continue throughout the lifespan. Previous studies revealed that male rats exhibited significantly higher levels of contextual fear memory than female rats. However, it remains unknown whether a sex difference exists in the contextual fear extinction. To address this issue, male, normally cycling female, and ovariectomized (OVX) female Sprague‐Dawley rats were subjected to contextual fear conditioning and extinction trials. Here we report that although male rats exhibited higher levels of freezing than cycling female rats after contextual fear conditioning, female rats subjected to conditioning in the proestrus and estrus stage exhibited an enhancement of fear extinction than male rats. An estrogen receptor (ER) β agonist diarylpropionitrile but not an ERα agonist propyl‐pyrazole‐triol administration also enhanced extinction of contextual fear in OVX female rats, suggesting that estrogen‐mediated facilitation of extinction involves the activation of ERβ. Intrahippocampal injection of estradiol or diarylpropionitrile before extinction training in OVX female rats remarkably reduced the levels of freezing response during extinction trials. In addition, the locomotion or anxiety state of female rats does not vary across the ovarian cycle. These results reveal a crucial role for estrogen in mediating sexually dimorphic contextual fear extinction, and that estrogen‐mediated enhancement of fear extinction involves the activation of ERβ. © 2009 Wiley‐Liss, Inc.  相似文献   
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AIM: To evaluate and validate the national trends and predictors of in-patient mortality of transjugular intrahepatic portosystemic shunt(TIPS) in 15 years.METHODS: Using the National Inpatient Sample which is a part of Health Cost and Utilization Project, we identified a discharge-weighted national estimate of 83884 TIPS procedures performed in the United States from 1998 to 2012 using international classification of diseases-9 procedural code 39.1. The demographic, hospital and co-morbility data were analyzed using a multivariant analysis. Using multi-nominal logistic regression analysis, we determined predictive factors related to increases in-hospital mortality. Comorbidity measures are in accordance to the Comorbidity Software designed by the Agency for Healthcare Research and Quality.RESULTS: Overall, 12.3% of patients died during hospitalization with downward trend in-hospitalmortality with the mean length of stay of 10.8 ± 13.1 d. Notable, African American patients(OR = 1.809 vs Caucasian patients, P 0.001), transferred patients(OR = 1.347 vs non-transferred, P 0.001), emergency admissions(OR = 3.032 vs elective cases, P 0.001), patients in the Northeast region(OR = 1.449 vs West, P 0.001) had significantly higher odds of inhospital mortality. Number of diagnoses and number of procedures showed positive correlations with in-hospital death(OR = 1.249 per one increase in number of procedures). Patients diagnosed with acute respiratory failure(OR = 8.246), acute kidney failure(OR = 4.359), hepatic encephalopathy(OR = 2.217) and esophageal variceal bleeding(OR = 2.187) were at considerably higher odds of in-hospital death compared with ascites(OR = 0.136, P 0.001). Comorbidity measures with the highest odds of in-hospital death were fluid and electrolyte disorders(OR = 2.823), coagulopathy(OR = 2.016), and lymphoma(OR = 1.842).CONCLUSION: The overall mortality of the TIPS procedure is steadily decreasing, though the length of stay has remained relatively constant. Specific patient ethnicity, location, transfer status, primary diagnosis and comorbidities correlate with increased odds of TIPS in-hospital death.  相似文献   
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The liver is a common site of metastasis, with essentially all metastatic malignancies having been known to spread to the liver. Nearly half of all patients with extrahepatic primary cancer have hepatic metastases. The severe prognostic implications of hepatic metastases have made surgical resection an important first line treatment in management. However, limitations such as the presence of extrahepatic spread or poor functional hepatic reserve exclude the majority of patients as surgical candidates, leaving chemotherapy and locoregional therapies as next best options. Selective internal radiation therapy (SIRT) is a form of catheter-based locoregional cancer treatment modality for unresectable tumors, involving trans-arterial injection of microspheres embedded with a radio-isotope Yttrium-90. The therapeutic radiation dose is selectively delivered as the microspheres permanently embed themselves within the tumor vascular bed. Use of SIRT has been conventionally aimed at treating primary hepatic tumors (hepatocellular carcinoma) or colorectal and neuroendocrine metastases. Numerous reviews are available for these tumor types. However, little is known or reviewed on non-colorectal or non-neuroendocrine primaries. Therefore, the aim of this paper is to systematically review the current literature to evaluate the effects of Yttrium-90 radioembolization on non-conventional liver tumors including those secondary to breast cancer, cholangiocarcinoma, ocular and percutaneous melanoma, pancreatic cancer, renal cell carcinoma, and lung cancer.  相似文献   
77.
Using a microarray technique, we found decorin to be underexpressed, but osteopontin (OPN) to be overexpressed, in esophageal squamous cell carcinoma (ESCC). This study aims to examine whether plasma decorin and OPN plus personal substances use (tobacco, alcohol and areca) can serve as suitable clinical markers to predict the presence of ESCC. In total, 570 archived plasma specimens (275 patients and 295 controls) were collected from 2 medical centers in Taiwan between 2000 and 2008. Decorin and OPN protein levels were measured by ELISA. Means and standard deviation of plasma decorin were 5.6 ± 3.6 ng/ml in case patients, which were significantly lower than those in controls (7.8 ± 3.1, p < 0.0001). Plasma OPN levels in case patients were not significantly different from controls (p = 0.33). When compared to subjects with the lowest quartile of plasma decorin, those with the highest quartile one had a significantly lower risk to have ESCC (Adjusted OR = 0.03, p < 0.001). Receiver operator characteristic (ROC) analysis was performed for the combination of plasma decorin and 3 substances use (smoke, alcohol and areca) for the patients compared with the controls. The area under the curve was 88.6% and the optimal cut‐point of ROC curve (any 3 factors) had 73.5% sensitivity and 90.2% specificity with ~82% of corrected classification. Plasma decorin, but not OPN, is a potential clinical marker for the detection of ESCC. When plasma decorin plus the use of the 3 substances are combined, this factor cluster could be used to detect the presence of ESCC.  相似文献   
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The role of hyperglycaemia in the pathogenesis of hypotension in diabetic disorders was investigated using the changes in cardiac M2-muscarinic receptor (M2-mAChR) gene expression in type-1-like diabetic rats and cultured cardiomyocytes. Blood pressure was markedly decreased in diabetic rats following the intravenous injection of streptozotocin (STZ) for 8 weeks. Also, the baroreflex sensitivity (ΔHR/ΔBP), as measured by the changes in heart rate (ΔHR) and mean blood pressure (ΔBP) 1 min after the intravenous injection of phenylephrine (10 μg/kg), was significantly increased. Arecaidine propargyl ester (APE), a M2-mAChR agonist produced a marked reduction in heart rate in these diabetic rats. Normalization of plasma glucose in diabetic rats using insulin (0.5 IU) or phlorizin (1 mg/kg) injection attenuated the blood pressure reduction and reversed the mRNA and protein levels of cardiac M2-mAChR. A high concentration of glucose (20 mmol/l) directly influenced the increase in gene expression of M2-mAChR in the H9c2 cardiac cell line. Hyperglycaemia induced an increase in cardiac M2-mAChR gene expression, suggesting a role in the pathogenesis of hypotension in diabetic disorders.  相似文献   
80.
Intrascan subject movement in clinical MR spectroscopic examinations may result in inconsistent water suppression that distorts the metabolite signals, frame‐to‐frame variations in spectral phase and frequency, and consequent reductions in the signal‐to‐noise ratio due to destructive averaging. Frame‐to‐frame phase/frequency corrections, although reported to be successful in achieving constructive averaging, rely on consistent water suppression, which may be difficult in the presence of intrascan motion. In this study, motion correction using non–water‐suppressed data acquisition is proposed to overcome the above difficulties. The time‐domain matrix‐pencil postprocessing method was used to extract water signals from the non–water‐suppressed spectroscopic data, followed by phase and frequency corrections of the metabolite signals based on information obtained from the water signals. From in vivo experiments on seven healthy subjects at 3.0 T, quantification of metabolites using the unsuppressed water signal as a reference showed improved correlation with water‐suppressed data acquired in the absence of motion (R2 = 0.9669; slope = 0.94). The metabolite concentrations derived using the proposed approach were in good agreement with literature values. Computer simulations under various degrees of frequency and phase variations further demonstrated robust performance of the time‐domain postprocessing approach. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
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