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71.
72.
The internal mammary artery (IMA) is increasingly used as a coronary bypass conduit because of better long-term patency and improved prognosis as compared with venous grafts. Previous investigators have suggested that the “steal” of blood flow of the IMA graft via the subclavian artery or a persistent large side branch of the graft may lead to its thinning. However, only a few reports have described the embolization of a large side branch using a transcatheter procedure. We present a case of repeated embolization of a large lateral costal side branch of the left internal mammary arterial graft applying gelatin sponge particles and micro coils, as well as angioplasty to the graft conduit, with resulting easing of chest pain.  相似文献   
73.
Neural and humoral autonomic mechanisms may be important in the maintenance of blood flow in the masseter muscle (MBF). However, their interactions remain unclear. In this study, we examined interactions between neural and humoral regulation of MBF and investigated the mechanisms mediating these interactions in urethane-anesthetized rats. Stimulation of the adrenal nerve (AN) projecting to the adrenal medulla increased MBF, and this increase was mediated by β-adrenoceptors. Sectioning of the superior cervical sympathetic trunk (CST) significantly inhibited increases in MBF induced by AN stimulation during high activity in the CST, but not during low activity. AN stimulation with clonidine after CST sectioning induced a significant increased in MBF, however phenylephrine had no observable effect. Pretreatment with yohimbine or propranolol significantly inhibited the increase in the MBF. Our results suggest an interaction between β-adrenergic vasodilation evoked by circulating adrenaline and the cervical sympathetic nerves that is mediated by α2-adrenoceptors in the masseter muscle.  相似文献   
74.
Levels of 3‐methoxy‐4‐hydroxyphenylglycol (MHPG) may reflect central noradrenergic activity. In this study, we investigated salivary MHPG changes after awakening, and explored their relationships with cortisol and peripheral autonomic activity. The participants were 25 college students. Saliva samples were collected on awakening and 30 min after awakening to determine MHPG and cortisol. Ambulatory electrocardiograms were obtained to assess heart rate, cardiac sympathetic index (CSI), and cardiac vagal index (CVI) before and after awakening. MHPG levels increased significantly during the first 30 min after awakening. Similarly, cortisol, heart rate, and CSI increased during the 30 min after awakening, but changes in MHPG did not correlate with changes in cortisol, heart rate, CSI, and CVI during that period. This study demonstrated that salivary MHPG levels increase after awakening, in common with cortisol, heart rate, and cardiac sympathetic activity.  相似文献   
75.
76.
Human gut microbiota is being increasingly recognized as a player in colorectal cancers (CRCs). Evidence suggests that Fusobacterium nucleatum (F. nucleatum) may contribute to disease progression and is associated with CpG island methylator phenotype (CIMP) and microsatellite instability (MSI) in CRCs; however, to date, there are no reports about the relationship between F. nucleatum and molecular features in the early stage of colorectal tumorigenesis. Therefore, we investigated the presence of F. nucleatum in premalignant colorectal lesions. In total, 465 premalignant lesions (343 serrated lesions and 122 non‐serrated adenomas) and 511 CRCs were studied. We determined the presence of F. nucleatum and analyzed its association with molecular features including CIMP, MSI and microRNA‐31 status. F. nucleatum was detected in 24% of hyperplastic polyps, 35% of sessile serrated adenomas (SSAs), 30% of traditional serrated adenomas (TSAs) and 33% of non‐serrated adenomas. F. nucleatum was more frequently detected in CIMP‐high premalignant lesions than in CIMP‐low/zero lesions (p = 0.0023). In SSAs, F. nucleatum positivity increased gradually from sigmoid colon to cecum (p = 0.042). F. nucleatum positivity was significantly higher in CRCs (56%) than in premalignant lesions of any histological type (p < 0.0001). In conclusion, F. nucleatum was identified in premalignant colorectal lesions regardless of histopathology but was more frequently associated with CIMP‐high lesions. Moreover, F. nucleatum positivity increased according to histological grade, suggesting that it may contribute to the progression of colorectal neoplasia. Our data also indicate that F. nucleatum positivity in SSAs may support the “colorectal continuum” concept.  相似文献   
77.
OBJECTIVE: The role of duodenal contents refluxing into the esophagus in producing reflux esophagitis (RE) remains unclear. We aimed to assess the impact of esophageal bile exposure on the genesis of RE in reference to esophageal pH changes in the absence of gastric acid after total gastrectomy. METHODS: Thirty patients having undergone total gastrectomy were studied with concurrent 24-h esophageal pH and bilimetric monitoring, and were divided into two groups based on endoscopic esophageal mucosal findings: without RE, group 1 (n = 24) and with RE, group 2 (n = 6). Esophageal bile exposure was defined as bilirubin absorbance >0.14 detected in the esophagus. RESULTS: 1) The percentage total time of esophageal bilirubin absorbance >0.14 was not correlated with that of esophageal pH >7.0, >7.4, and >8.0. 2) All parameters for esophageal bilirubin absorbance >0.14 in group 2 were significantly higher than those in group 1, whereas none of the parameters for esophageal pH >7.0, >7.4, and >8.0 showed a significant difference between the two groups. 3) The percentage total time of esophageal bilirubin absorbance >0.14 was over 50% in all subjects with RE, and six of seven subjects with that over 50% had RE. CONCLUSIONS: Esophageal bile exposure plays an important role in the genesis of RE in the absence of gastric acid, which is assessed better with the measurement of esophageal bilirubin absorbance than that of esophageal pH.  相似文献   
78.
BACKGROUND: Until now, large-scale nationwide surveys of acute myocardial infarction (AMI), such as those performed in Europe and America, have not been performed in Japan. Therefore, in 2000 the Japanese Coronary Intervention Study (JCIS) group conducted a nationwide survey on the incidence of AMI in Japan. METHODS AND RESULTS: Questionnaires were collected from 8,268 facilities throughout Japan. The total annual number of patients with AMI was 66,459 (52.4 patients/10(5) population), and the AMI incidence rate in Japan was approximately 25% of that in the United States. Most facilities with AMI patients treated less than 50 AMI patients annually, and that number was 45.0% of total AMI patients. The incidence of AMI patients was highest in Kochi, Kumamoto, and Wakayama prefectures, and lowest in Yamanashi, Saitama and Shiga prefectures. The ratio of the highest incidence to the lowest incidence was 2.0. A significant correlation was observed between the mean age of the prefectural population, as a coronary risk factor, and the incidence of AMI. CONCLUSIONS: The incidence of AMI in Japan is approximately 25% that in the United States and it varies considerably among the prefectures, one of the causes being the difference in the mean age. This provides important information for assessing the guidelines for Japanese patients with AMI.  相似文献   
79.
The asialoglycoprotein receptor (ASGPR) is abundantly expressed on the sinusoidal surfaces of hepatocytes. We aimed to clarify the clinical significance of the regional distribution of ASGPRs in the human liver, especially in chronic viral hepatitis. Eighteen volunteers, 34 patients with chronic hepatitis, and 33 patients with cirrhosis (11/Child-Pugh A, 11/Child-Pugh B, 11/Child-Pugh C) were studied using a newly developed, conventional technetium-99m-diethylenetriaminepentaacetic acid-galactosyl human serum albumin ((99m)Tc-GSA), single photon emission computed tomography (SPECT) method. Using Cantlie's line as a guide, ASGPR dynamics were analyzed separately in the right and left lobes, as well as in the whole liver, using novel indices (the liver uptake ratio [LUR] and the liver uptake density [LUD], which reflect the amount and density of ASGPRs in the liver, respectively). Mean LUR and LUD values for the whole liver and the right and left lobes decreased with increasing progression of chronic viral hepatitis. The LUR for the whole liver correlated well with parameters measuring the hepatic functional reserve and the platelet count. The right LUR correlated particularly well with conventional liver function tests, and comparison of the right LUD with histologic findings showed that it was a good indicator of periportal and/or bridging necrosis and fibrosis. In conclusion, our (99m)Tc-GSA SPECT method was clinically useful in evaluating regional hepatic function and the progression of chronic viral hepatitis using dynamic changes in ASGPRs.  相似文献   
80.
BACKGROUND: Despite the pluripotency of embryonic stem (ES) cells, the specific control of their cardiomyogenic differentiation remains difficult. The aim of the present study was to investigate whether growth factors may efficiently enhance the in vitro cardiac differentiation of ES cells. METHODS AND RESULTS: Recombinant growth factors at various concentrations or their inhibitors were added according to various schedules during the cardiomyogenic differentiation of ES cells. Cardiomyogenic differentiation was assessed by mRNA and protein expressions of several cardiomyocyte-specific genes. Basic fibroblast growth factor-2 (FGF-2) and/or bone morphogenetic protein-2 (BMP-2) efficiently enhanced the cardiomyogenic differentiation, but only when they were added at the optimal concentration (1.0 ng/ml in FGF-2 and 0.2 ng/ml in BMP-2; relatively lower than expected in both cases) for the first 3 days. Inhibition of FGF-2 and/or BMP-2 drastically suppressed the cardiomyogenic differentiation. CONCLUSION: FGF-2 and BMP-2 play a crucial role in early cardiomyogenesis. The achievement of efficient cardiac differentiation using both growth factors may facilitate ES cell-derived cell therapy for heart diseases as well as contribute to developmental studies of the heart.  相似文献   
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