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Ureteral hernia is uncommon and usually misdiagnosed. From an anatomic point of view, we can distinguish between two uretero-inguinal hernias: intraperitoneal and extraperitoneal. Ureter inguinal hernias are nearly always indirect. This kind of hernia can include the ureter alone or, frequently, other abdominal sliding organs within the hernia sac (bladder, bowel tracts, etc.). Kidneys and urinary tracts present normal anatomic conformation, although renal ptosis may be found. As of July 2004, 139 cases of ureteral hernia had been described in the literature. Here we report a case of inguino-scrotal herniation of double district ureter and review the current literature to analyze the main clinical characteristics of this pathology and to establish pitfalls.  相似文献   
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BACKGROUND: Homocysteine (Hcy) is an independent risk factor for cardiovascular disease (CVD). Individuals with Type 1 and Type 2 diabetes are more susceptible to the effects of homocysteine than non-diabetic subjects. The interaction between homocysteine-thiolactone (Hcy-thiolactone), a reactive product of Hcy, and low-density lipoproteins (LDL) induces the formation of homocystamide-LDL adducts (Hcy-LDL) and it has been suggested that homocysteinylation could increase atherogenicity of lipoproteins. AIM: The aim of the study was to compare the effect of in vitro homocysteinylation of LDL isolated from healthy control subjects (C-LDL) and from Type 1 diabetic patients (DM-LDL) and to investigate the effect of homocysteinylated LDL (Hcy-C-LDL and Hcy-DM-LDL) on peroxynitrite production of endothelial cells. METHODS: The in vitro homocysteinylation of LDL isolated from control (n = 12) and DM subjects (n = 12) was carried out by incubating lipoproteins with Hcy-thiolactone. The reaction was verified by quantifying the increase in sulphydryl groups (-SH groups) in Hcy-LDL with respect to control LDL. Control and homocysteinylated LDL were incubated with human aortic endothelial cells (HAEC) in culture. Peroxynitrite production in cells treated in different experimental conditions was assayed by a fluorimetric method. RESULTS: The increase in -SH groups after incubation with homocysteine was greater in LDL from diabetic subjects compared with LDL from control subjects (P < 0.001). In addition, peroxynitrite production from HAEC incubated with Hcy-LDL from diabetic patients was greater than after incubation with Hcy-LDL from control subjects and untreated LDL from diabetic patients (P < 0.001). CONCLUSIONS: These results show that LDL from diabetic patients is more susceptible to in vitro homocysteinylation than LDL from non-diabetic individuals and demonstrate that the compositional changes in Hcy-LDL from diabetic subjects have cytotoxic effects on human endothelial cells.  相似文献   
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Schistosoma mansoni infection, both in humans and in animal models, is known to induce granulomas in the liver and intestine. It has also been reported that in humans the eggs of this parasite can reach the brain, causing psychiatric and neuropathological disorders. Whether this also occurs in rodents is unknown. To answer this question, mice were infected with this parasite and the central nervous system (CNS) examined at various time intervals. The results show that schistosomiasis induced granulomas in several regions of the CNS and increased nerve growth factor (NGF) levels in the cortex, hypothalamus and brain stem, but not in the hippocampus. The infection also caused paw hyperalgesia, as determined by the hot-plate test, and a local increase in NGF, but not in substance P. These findings indicate that the murine model of infection can be used for studying mechanisms leading to human neuroschistosomiasis and suggest that the neuropathological disorders and the sensory deficits observed in human schistosomiasis are associated with impaired levels of NGF in the peripheral and central nervous system. Received: 18 January 1996 / Revised, accepted: 16 April 1996  相似文献   
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Twenty-seven opening-wedge osteotomies of the proximal part of the tibia were performed in twenty-five patients who had genu recurvatum. In sixteen knees, the genu recurvatum was due entirely to osseous deformity. In the remaining eleven knees, it was due to a combination of osseous and soft-tissue deformity; in five, the deformity was predominantly osseous and in six, primarily in the soft tissues (the ligaments and capsule). The average age of the patients was twenty-three years (range, fifteen to fifty-four years). The osteotomy was proximal to the tibial tuberosity in twenty-two knees. In eighteen of these knees, the tuberosity was detached with its patellar ligament and then reattached to the proximal part of the tibia over the block of bone in the opened wedge; in the remaining four knees, the tibial tuberosity was not detached. The osteotomy was distal to the tuberosity in five knees. The patients were followed for an average of 14.5 years (range, three to thirty years). Of the eighteen knees in which the osteotomy had been proximal to the tibial tuberosity and the tuberosity had been detached and then reattached, nine (50 per cent) had a result that was excellent; five (28 per cent), good; and four (22 per cent), fair. Of the four knees in which the operation had been proximal to but without detachment of the tuberosity, one had a result that was excellent; two, good; and one, fair. Of the five knees in which the osteotomy was distal to the tibial tuberosity, one had a result that was good; three, fair; and one, poor. Of the twenty-one knees in which the deformity was entirely or predominantly osseous, eighteen (86 per cent) had an excellent or good result. None of the six knees in which the deformity was predominantly in the soft tissues had an excellent or good result. Patients in whom the deformity was not primarily osseous, and those in whom the operation was distal to the tibial tubercle, were much more likely to have a fair or poor result.  相似文献   
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Chitambar  CR; Zivkovic  Z 《Blood》1989,74(2):602-608
Information regarding transferrin (Tf) receptor degradation is largely incomplete. HL60 cells were shown to release to their growth medium a Tf-binding protein which could be immunoprecipitated by anti-Tf receptor monoclonal antibodies (MoAbs) B3/25 and OKT9. Soluble Tf receptor was detected in the medium within one hour of replating of cells, and its release was inhibited at 4 degrees C. The affinity of Tf for the soluble receptor released by cells (kd = 2.3 x 10(-10) mol/L) was slightly lower than its affinity for the detergent-solubilized cellular receptor (kd = 1.2 x 10(-10) mol/L). 125I-Tf internalized and released by cells subsequently bound to Tf receptor released by the same cells, and soluble Tf receptor in the conditioned medium (CM) inhibited 125I-Tf binding to intact cells. The soluble Tf receptor isolated from the CM was smaller (78,000 daltons) than the cell surface receptor (94,000 daltons) when analyzed by gel electrophoresis under reducing conditions. Isolated cell membranes readily released soluble receptor; however, this release could be blocked by protease inhibitors. The soluble Tf receptor may represent the extracytoplasmic domain of the cellular Tf receptor released from the surface of HL60 cells through proteolytic cleavage by a membrane-based protease.  相似文献   
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Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm).  相似文献   
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