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Background. Epidermotropic lymphoid T cell infiltrates are part of a continuous spectrum of lesions ranging from “benign” parapsoriasis to frank cutaneous T cell lymphoma (CTCL, mycosis fungoides). Either the clinical or histologic differentiation between these entities prove often difficult and the prognosis may be difficult to assess. Patients and Methods. We studied 15 patients, men aged 50 to 81 years, mean ± SD 68 ± 12 years, with patch-plaque CTCL. Sections from punch biopsies from active lesions were stained with Feulgen reagent, coupled with a “twin” adjacent hematoxylin and eosin (H&E)-stained section and analyzed with a VIDAS Zeiss-Kontron Image Analyzer. At least 50 dermal infiltrating cells and 50 epidermotropic Pautrierian cells per specimen were counted and the biopsies were repeated periodically. Results. Nine patients with aneuploid Pautrierian cell DNA patterns did well after conventional phototherapy (dermal cell ploidy was irrelevant), whereas six patients with euploid Pautrierian cell DNA patterns had to be treated aggressively (IFN + retinoids, COP). Clinical and histopathologic aspects of the first group were comparable to those of the second group. Conclusions. The classical cytophotometric aphorism seems to be reversed in this sample: “The more abnormal the ploidy of epidermotropic Pautrierian cells, the better the prognosis.” Euploid epidermotropic cell prove more efficient in invading the skin and other areas and this efficiency may be reflected in more aggressive trends in the evolution of the lymphoma. Thus, DSM analysis of epidermotropic cells could prove very useful as an inexpensive tool for routine CTCL grading.  相似文献   
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Portal venous flow velocity (PFV) was measured with duplex-Doppler equipment in 50 normal subjects and in 117 patients with suspected chronic liver disease who showed no evidence of decompensation such as ascites, hepatic encephalopathy, jaundice or oesophageal bleeding. All the patients underwent percutaneous liver biopsy which demonstrated non-cirrhotic liver disease in 58 cases (CH-patients: steatosis 8, persistent chronic hepatitis 8, active chronic hepatitis 42) and liver cirrhosis in the other 59 cases (LC-patients). The normal subjects and the CH-patients had similar values of max-PFV and mean-PFV (max-PFV 26.7±3.2 and 25.7±3.4 cm/s respectively; mean-PFV 22.9±2.8 and 22.4±3.8 cm/s respectively). The LC-patients’ values (max-PFV 19.3±3.5; mean-PFV 16.9±2.9) were significantly lower than those of the normal subjects (P<0.001) and of the CH-patients (P<0.001). Considering the normal max-PFV to be in the range 20–33.1 cm/s (mean±2 s.d. of the normal subjects, 95% confidence limits), max-PFV was reduced in 0/50 normal subjects, 1/58 CH-patients and 39/59 LC-patients (66.1% sensitivity; 98.2% specificity). In conclusion, the duplex-Doppler measurement of PFV is of great interest in the diagnostic study of patients with suspected chronic compensated liver disease and in the early diagnosis of cirrhosis. A low max-PFV is a reliable pointer to liver cirrhosis, whereas a normal max-PFV indicates a non-cirrhotic liver disease but is less probative. Each centre should standardize normal PFV values in order to establish their own threshold value for diagnosing liver cirrhosis.  相似文献   
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Abstract Helicobacter pylori is a major risk factor for peptic ulcer, but studies on the role of H. pylori infection in gastric pathology are limited due to lack of convenient models resembling H. pylori infection in humans. We studied the effects of inoculation of conventional BALB/c mice with a toxigenic (cytotoxin associated gene A (cagA)+ and vacuolating cytotoxin gene A (vacA+) H. pylori strain on the course of healing of gastric ulcers. Following inoculation of toxigenic H. pylori or vehicle, gastric ulcers were produced in mice, which were then killed either at day 0 or after 2, 4, 7, 14 or 28 days and ulcer area and gastric blood flow (GBF) were determined. Gastric secretions from mice with chronic gastric fistulae were studied before and after inoculation with toxigenic H. pylori or vehicle (saline). The area (7 mm2) of ulcers in control mice decreased gradually and disappeared almost completely after 14 or 28 days. The ulcers in H. pylori-infected mice were present at all test days, showing a larger area than in vehicle control animals. The GBF in control mice rose gradually with decreasing ulcer size, being significantly higher at the ulcer margin than the ulcer crater. In contrast, the GBF in H. pylori-infected mice was significantly lower at the ulcer area than that in the vehicle controls but, again, the GBF at the ulcer margin was always higher than at the ulcer crater. Gastric acid output was reduced by more than 50% immediately after H. pylori inoculation and was accompanied by a significant increase in plasma gastrin release and a fall in gastric luminal somatostatin content. These secretory changes persisted at all test days. Oedema/congestion of surface epithelium appeared after 7 days and mucosal inflammatory infiltration appeared after 14 days, to further increase after 28 days, upon the induction of ulcer. Plasma interleukin (IL)-Iß and IL-12 were significantly elevated above the initial values compared with controls. Conventional mice with gastric ulcers can be successfully infected with an H. pylori strain expressing cagA and vacA cytotoxin and this infection markedly delays healing of the ulcers, probably due to the fall in GBF in the ulcer area, mucosal inflammation, cytokine release and impairment of the gastrin-somatostatin link.  相似文献   
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Peptides with a regular sequence of enantiomeric residues (l and d ) along the chain have received considerable attention because of their accessibility to unique conformations and because they are model compounds for the naturally occurring peptide gramicidin A, which shows monovalent cation selective transmembrane transport. The solid-state structure of the linear hexapeptide t-Boc-(d -aIle-l -Ile)3-OMe has been determined by X-ray diffraction techniques and refined to a final R factor of 0.068. The molecule shows a bent U-shaped conformation stabilized by three intramolecular H-bonds of the N—H?O=C type: a type II β-bend (4 → 1 bend or C10 ring structure) with l -Ile2 and d -aIle3 at positions 2 and 3 of the bend, an α-turn (5 → 1 bend or C13 ring structure) and a 1 → 5 bend or C17 ring structure. The first two 10-membered and 13-membered bends are enclosed in the latter 17-membered hydrogen-bonded ring structure. This structural motif is common to hepta- and octa-peptide cyclic molecules, showing that ring closure is not required to achieve a particular topology in the molecular design of specific bended conformations. © Munksgaard 1995.  相似文献   
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We describe a patient who developed cardiac tamponade during electrophysiological mapping aimed at ablating an atrioventricular accessory pathway. Transesophageal echocardiography showed compression of the left pulmonary veins due to pneumohemomediastinum secondary to left subclavian vein cannulation.  相似文献   
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