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1.
In order to study the biological activity of endogenous digitalis-like substance (DLS) and Na-K-ATPase inhibitor (ATPI), human urine was partially purified and administered to rats, and its effects on the urinary volume, urinary Na excretion and blood pressure (BP) were determined. In addition, the effect on myocardial Na-K-ATPase activity was also measured. After the extraction of 40L of urine with a reversed phase cartridge column (S-fraction), 20 ml of chloroform was added and extraction was repeated. The chloroform layer was applied to an open silica gel column, and at a fraction with ethylacetate: methanol (60: 40, T-1 fraction), DLS and ATPI were eluted at the highest concentration. The water layer was treated with charcoal (D-1 fraction). The acute administration of K-1, T-1 fraction to rats in vivo caused significant rises in urinary volume, urinary Na excretion and BP. In chronic administration of K-1 fraction, urinary Na excretion was significantly elevated and myocardial Na-K-ATPase activity was also significantly suppressed. These results suggest that DLS and ATPI cause increase in the urinary volume and urinary Na excretion and also possess a hypertensive action; and moreover, these substance may affect the heart like cardiotonic steroids and regulate BP by increasing cardiac contractility.  相似文献   
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The colonic mucosa of 30 patients with ulcerative colitis was analyzed by an immunohistochemical technique. A quantitative evaluation for lymphocyte subsets show significantly increased numbers of CD3+, CD4+, CD8+, and CD28+ cells in ulcerative colitis cases of histological grades 3, 4 and 5 by Matts' classification comparing to normal control cases. CD4/CD8 ratio in each histological grade of ulcerative colitis was not significantly different from those in normal controls and disease controls (infectious colitis cases). However, CD28/CD3 ratio was increased significantly in ulcerative colitis cases of histological grades 3, 4 and 5 comparing to control cases. Most of the lymphocytes were positive for lymphocyte function-associated antigen-1 alpha (LFA-1 alpha). There were increased numbers of S100-beta + dendritic cells and CD68+ macrophages in the luminal area of the lamina propria. Moreover double stainings revealed that most of the S100-beta + dendritic cells and CD68+ macrophages were intercellular adhesion molecule-1 (ICAM-1, a ligand for LFA-1) positive. These findings suggested that the expression of ICAM1 on S100-beta + dendritic cells and CD68+ macrophages is important by the interaction with T cells and T cell antigen recognition.  相似文献   
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The objective of this study was to quantify, in vivo, constitutive and tumor necrosis factor alpha (TNF-alpha)-enhanced expression of mucosal addressin cell adhesion molecule-1 (MAdCAM-1) in different tissues from healthy wild-type mice (C57BL/6) as well as interleukin-10 (IL-10)-deficient mice with and without active colitis. Using the dual radiolabel monoclonal antibody technique, we found substantial constitutive expression of MAdCAM-1 in the intestine, colon, and mesenteric lymph nodes. MAdCAM-1 expression in these tissues was significantly enhanced, in a time-dependent manner, by systemic administration of TNF-alpha. Maximum surface expression was observed at 18 h after TNF-alpha administration and remained significantly elevated at 48 h post-TNF-alpha injection. No significant constitutive nor TNF-alpha-induced expression of MAdCAM-1 was detected in skeletal muscle, brain, or heart. In IL-10-deficient (IL-10 k/o) mice with no clinical or histological evidence of colitis, constitutive and TNF-alpha-induced expression of MAdCAM-1 in the intestine, cecum, and colon was not different from those values obtained with healthy wild-type controls. IL-10-deficient mice with active colitis exhibited a four- to fivefold greater expression of MAdCAM-1 in the cecum and colon compared with their healthy controls or to IL-10 k/o mice with no evidence of colitis. Taken together, these data demonstrate that TNF-alpha enhances surface expression of MAdCAM-1 in intestinal and colonic tissues to the same extent in both wild-type and IL-10 k/o mice with no colonic inflammation, whereas IL-10 k/o mice with active colitis exhibited a profound up-regulation of MAdCAM-1 in the colon.  相似文献   
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To determine whether primary B-cell gastric lymphoma (GL) is one entity, we examined the expression of three adhesion molecules in the microvasculature of lymphomas. Stromal cells, including vascular endothelial cells, within lymphoid follicles of the gastric mucosa were also investigated. Twenty-two surgical specimens of GL were classified into low-grade malignant lymphoma arising from mucosa-associated lymphoid tissue (low-grade lymphoma, n=9), and high-grade malignant lymphoma with (secondary high-grade lymphoma, n=6) or without (primary high-grade lymphoma, n=7) a low-grade component. The proportion of venules positive for ELAM-1 or VCAM-1 was significantly higher (P<0.001) in primary high-grade lymphoma than in low-grade and secondary high-grade lymphomas. In gastric lymphoid follicles, the stromal cells of the germinal centre (GC) were positive for ICAM-1, ELAM-1, and VCAM-1, but the stromal cells of the marginal zone (MZ) were positive only for ICAM-1. We found two patterns of adhesion molecule expression in gastric lymphoid follicles, the MZ pattern and the GC pattern. Low-grade and secondary high-grade lymphomas, which had the MZ pattern, might be of MZ-cell lineage, but most primary high-grade lymphomas, which had the GC pattern, might be of follicular centre cell lineage.  相似文献   
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Omeprazole markedly inhibits basal and stimulated gastric acid secretion and has the ability to produce hypergastrinemia and hyperplasia of enterochromaffin-like cells in humans. On the other hand, paunotol, an acyclic diterpene alcohol, has been reported to inhibit gastrin release by stimulating endogenous secretin release. We investigated the effect of plaunotol on serum gastrin levels after six to eight weeks of omeprazole (20 mg/day) administration in 22 patients (16 males, 6 females; mean age 52.3, range 36–70 years) with peptic ulcer disease. The patients were randomized to the following two groups: 11 subjects with omerprazole alone (single group) and 11 with omeprazole plus plaunotol (240 mg/day) (combination group) treatment. There were no significant differences between the two groups concerning age, sex, ulcer stage, ulcer history, environmental factors, andHelicobacter pylori (HP) prevalence. After complete drug(s) administration, serum immunoreactive (ir) -gastrin levels increased significantly in the single group (P<0.001) in contrast to the combination group, and plaunotol significantly inhibited hypergastrinemia induced by omeprazole administration (P<0.001). Significant increases in serum ir-calcitonin gene-related peptide concentrations were observed in the combination group compared to the single group (P<0.05). However, there were no significant changes in serum ir-secretin, somatostatin, and vasoactive intestinal polypeptide levels as well as ulcer healing and HP prevalence between the two groups. These findings suggest that plaunotol may suppress hypergastrinemia induced by long-term omeprazole administration, at least partly, via a certain brain-gut hormone affecting gastrin release.  相似文献   
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We describe a rare case of pancreas divisum associated with a giant retention cyst (cystic dilatation of the dorsal pancreatic duct), presumably formed following obstruction of the minor papilla. The patient was treated by pancreatico(cysto)jejunostomy. A 50-year-old man was admitted with complaints of increasing upper abdominal distension and body weight loss. There was no previous history of pancreatitis, gallstones, drinking, or abdominal injury. An elastic-hard tumor-like resistance was palpable in the upper abdomen. Computed tomography and ultrasound (US) examinations revealed a giant cystic lesion expanding from the pancreas head to the tail. Endoscopic retrograde cholangiopancreatography findings showed a looping pancreatic duct which drained only the head and uncinate process of the pancreas to the main papilla. A US-guided puncture to the cystic lesion revealed that the lesion continued to the main pancreatic duct in the tail of pancreas. The lesion was connected to a small cystic lesion, which was located inside the minor papilla, and ended there. The amylase level in liquid aspirated from the cyst was 37 869 IU/l, and the result of cytological examination of the liquid showed class II. A pancreatico(cysto)jejunostomy was performed, with the diagnosis being pancreas divisum associated with a retention cyst following obstruction of the minor papilla. The histological findings of a specimen from the cyst wall revealed that the wall was a pancreatic duct covered with mildly inflammatory duct epithelium; there was no evidence of neoplasm. The patient is currently well, and a CT examination 2 years after the operation showed disappearance of the cyst and normal appearance of the whole pancreas. Received: April 24, 2001 / Accepted: September 14, 2001  相似文献   
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BACKGROUND: Although increased levels of interleukin (IL)-8 are known to be associated with infiltration of neutrophils in the gastric mucosa with Helicobacter pylori infection, no study has investigated the relationship between local IL-8 levels and neutrophil infiltration in the duodenal mucosa of patients with duodenal ulcer (DU). METHODS: Duodenal mucosal biopsy specimens with and without gastric metaplasia (GM) were obtained from patients with DU and controls with an endoscopic methylene blue (MB) staining method. Levels of IL-8 secreted in the organ cultures of biopsy specimens were measured with an enzyme-linked immunosorbent assay. The number of myeloperoxidase-positive neutrophils infiltrating the lamina propria was determined in immunohistochemically stained tissue sections. RESULTS: Histologic assessment showed that there was a strong correlation between the absence of endoscopic MB staining and the extent of GM. The levels of IL-8 in both duodenal and antral mucosal tissues were significantly higher in patients with H. pylori infection than in those without infection. In patients with DU the duodenal mucosal tissues with GM (MB-unstained mucosa) showed significantly higher levels of IL-8 than those without GM (MB-stained mucosa) or the antral mucosa. The number of neutrophils showed similar variations among DU and control patients with a positive correlation with IL-8 activity. The levels of IL-8 and the number of neutrophils decreased after H. pylori eradication in both duodenal and antral mucosal tissues, and these changes were more remarkable in the duodenal mucosal tissues with GM. CONCLUSIONS: Increased IL-8 activity in the duodenal mucosa with GM may be important for ulcerogenesis in H. pylori-positive DU patients.  相似文献   
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