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91.
PURPOSE: To compare the pathological findings between multifocal choroiditis with panuveitis (MCP) and punctate inner choroidopathy (PIC). METHODS: Fourteen eyes of 14 patients clinically diagnosed as having MCP or PIC who underwent surgical excision of choroidal neovascularization (CNV) were studied. Immunohistochemical findings of the excised CNV in MCP (eight eyes) and PIC (six eyes) cases were compared. Antibodies against vascular endothelial growth factor (VEGF), CD68, CD3, and CD20 were used as primary antibodies. RESULTS: Expression of VEGF and CD68 in the CNV was observed in all MCF and PIC cases. In three of eight eyes with MCP, intraocular inflammatory findings were found clinically, while immunohistochemical study demonstrated infiltration of CD20-positive B lymphocytes in the CNV. No B lymphocyte infiltration was found in the six eyes with PIC. No differences in pathological findings were found between the five MCP eyes without intraocular inflammation and the six PIC eyes, with all eyes showing no B lymphocyte infiltration. CONCLUSIONS: In MPC cases showing clinical inflammatory findings, infiltration of B lymphocytes was also observed histopathologically, suggesting that the presence of inflammatory cells in the anterior chamber or vitreous body clinically is an indicator of active inflammatory CNV. However, this study clarifies that MCP eyes without intraocular inflammation and PIC eyes are not different in histopathological findings.  相似文献   
92.
The mechanism of action of 2(3)-tert-butyl-4-hydroxyanisole (2-BHA or 3-BHA) on rat forestomach epithelium was studied by examining the metabolites of BHA in the stomach and the covalent binding of BHA to macromolecules in the forestomach epithelium. Male F344 rats 6 weeks old were given a single intragastric injection of 1 g/kg body wt of [tert-14C]-3-BHA (Bu-3-BHA) or [methyl-14C]-3-BHA (Me-3-BHA), and 6 h later BHA metabolites in the forestomach, glandular stomach and stomach contents were examined by thin-layer chromatography. No significant amounts of metabolites were detected in the forestomach or glandular stomach epithelium and almost all the radioactivity in these tissues was extracted with organic solvents. In in vitro experiments also, no significant amounts of metabolites were detected when the 9000 g supernatant of the forestomach or glandular stomach epithelium, or gastric juice was incubated with Bu-3-BHA in the absence or presence of NADPH. In binding studies, rats were given Bu-3-BHA, [tert-14C]-2-BHA (Bu-2-BHA), Me-3-BHA or [methyl-14C] butylated hydroxytoluene (Me-BHT) intragastrically at a dose of 1 g/kg body wt with or without pretreatment with unlabelled 1% 3-BHA or BHT in the diet for 6 days. Six hours after treatment with a labelled compound, the rats were sacrificed and the DNA, RNA and protein of their forestomach, glandular stomach, liver and kidney were isolated. Bu-3-BHA, Bu-2-BHA and Me-3-BHA did not bind covalently to forestomach DNA or RNA, and the amounts of radioactivity of these compounds bound to proteins in the 4 tissues were similar. These findings suggest that BHA acts on the forestomach epithelium directly without metabolic activation, and that its action is not related to its binding to DNA or RNA.  相似文献   
93.
The dosimetric effect of set-up error in boron neutron capture therapy (BNCT) for head and neck cancer remains unclear. In this study, we analyzed the tendency of dose error by treatment location when simulating the set-up error of patients. We also determined the tolerance level of the set-up error in BNCT for head and neck cancer. As a method, the distal direction was shifted with an interval of 2.5 mm, from 0.0 mm to +20.0 mm and compared with the dose at the reference position. Similarly, the horizontal direction and vertical direction were shifted, with an interval of 5.0 mm, from −20.0 mm to +20.0 mm. In addition, cases with 3.0 mm and 5.0 mm simultaneous shifts in all directions were analyzed as the worst-case scenario. The dose metrics of the minimum dose of the tumor and the maximum dose of the mucosa were evaluated. From unidirectional set-up error analysis, in most cases, the set-up errors with dose errors within ±5% were Δdistal < +2.5 mm, Δhorizontal < ±5.0 mm and Δvertical < ±5.0 mm. In the simulation of 3.0 mm shifts in all directions, the errors in the minimum tumor dose and maximum mucosal dose were −3.6% ±1.4% (range, −5.4% to −0.6%) and 2% ±1.4% (range, 0.4% to 4.5%), respectively. From these results, if the set-up error was within ±3.0 mm in each direction, the dose errors of the tumor and mucosa could be suppressed within approximately ±5%, which is suggested as a tolerance level.  相似文献   
94.
The irradiation field of boron neutron capture therapy (BNCT) consists of multiple dose components including thermal, epithermal and fast neutron, and gamma. The objective of this work was to establish a methodology of dosimetric quality assurance (QA), using the most standard and reliable measurement methods, and to determine tolerance level for each QA measurement for a commercially available accelerator-based BNCT system. In order to establish a system of dosimetric QA suitable for BNCT, the following steps were taken. First, standard measurement points based on tissue-administered doses in BNCT for brain tumors were defined, and clinical tolerances of dosimetric QA measurements were derived from the contribution to total tissue relative biological effectiveness factor-weighted dose for each dose component. Next, a QA program was proposed based on TG-142 and TG-198, and confirmed that it could be assessed whether constancy of each dose component was assured within the limits of tolerances or not by measurements of the proposed QA program. Finally, the validity of the BNCT QA program as an evaluation system was confirmed in a demonstration experiment for long-term measurement over 1 year. These results offer an easy, reliable QA method that is clinically applicable with dosimetric validity for the mixed irradiation field of accelerator-based BNCT.  相似文献   
95.
A subchronic toxicity study of soybean extract was performed in F344 rats with dietary administration at concentrations of 0%, 1.25%, 2.5% and 5% for 13 weeks. No mortality or abnormal clinical signs in any group were observed. Body weight gains were decreased with a tendency for reduction of feed intake in the 1.25% and above female and 5% male groups. In males, absolute and relative liver weights were increased in the 1.25% and above groups. In females relative kidney weights were increased in the 1.25% and above groups. Other significant changes such as decreased RBC and hematocrit and increased urea nitrogen were detected in the 2.5% and/or 5% groups. On histopathological observation, atrophy of the ventral prostate was observed in all animals in the 5% male group. Mucification and atrophy of the vaginal epithelium and increased atretic follicles in ovaries were noted in 2.5% and 5% female rats. Based on the above findings the lowest-observed-adverse-effect level for male and female rats was estimated to be 1.25% (707.2 and 751.8 mg/kg b.w./day, respectively).  相似文献   
96.
Purpose Hypertension, one of the more common chronic diseases affecting the elderly, has been reported to influence leukocyte–endothelial cell interaction. The leukocyte-mediated inflammatory process contributes to age-related changes in vessels. This study was designed to evaluate age-related changes in leukocyte–endothelial cell interaction in the hypertensive rat retina. Methods Male spontaneous hypertensive rats (SHR; 1.5, 3, 6, 12, and 20 months of age) and age-matched Wistar-Kyoto rats (WKY) were used. The number of accumulated leukocytes was counted in sections of flat-mounted retinal tissue. The expression of intercellular adhesion molecule-1 (ICAM-1) and CD18 (the common β-chain of ICAM-1 ligands) was evaluated. Retinal thickness was evaluated histologically. Results The number of accumulated leukocytes and the expression of ICAM-1 and CD18 increased in the aged retina. The number of leukocytes that accumulated and the expression of CD 18 were significantly higher in the SHR group than in the WKY group (P < 0.01). In addition, retinal thickness decreased with age. Conclusion Leukocyte–endothelial cell interaction increased in the aged retina and these changes were more severe in SHR retina than in WKY retina. This increased interaction was first observed at 3 months, a relatively young age.  相似文献   
97.
98.
Background Disseminated intravascular coagulation (DIC) caused by placental abruption usually improves rapidly after prompt delivery and adequate anti-DIC treatment. Case A 30-year-old nulliparous woman suffered from placental abruption at the 25th week of pregnancy, and emergent cesarean section was done immediately. She exhibited DIC, which continued even after termination of the pregnancy and anti-DIC treatment. She also showed neutropenia. We closely observed her, and at the 58th day postpartum, blast cells appeared in the peripheral blood and she was diagnosed with acute promyelocytic leukemia (APL). Induction chemotherapy was done successfully. The close observation after delivery enabled us to make the prompt diagnosis/treatment, leading to the complete remission. Conclusion APL should be added to the list of differential diagnosis when DIC persists even after prompt delivery and appropriate anti-DIC treatment after placental abruption.  相似文献   
99.
100.
Open in a separate window OBJECTIVESAlthough reoperation has been increasingly performed in cardiovascular surgery in recent years, preventing surgical adhesions remains an unsolved complication. Therefore, this study aimed to investigate whether gelatine sealing sheets are more effective than fibrin sealing sheets in preventing surgical adhesions.METHODSBilateral femoral arteries of 20 beagle dogs under general anaesthesia were pricked with syringe needles, and gelatine and fibrin sealing sheets were applied on the bleeding points to make canine adhesion models. The femoral artery was harvested after 4 and 12 weeks to evaluate adhesion formations. The adhesive grade was quantified by scoring the area and strength of adhesion tissues. Histological staining was performed to examine the structural features of surgical adhesions.RESULTSSignificantly fewer macroscopic adhesions were observed with gelatine sealing sheets than those with fibrin sealing sheets at 4 and 12 weeks postoperatively. Microscopically, CD3+ T lymphocytes at 4 and 12 weeks postoperatively in gelatine sealing sheets were significantly lower than those in fibrin sealing sheets. Microvessel density determined by CD34 at 4 and 12 weeks postoperatively in gelatine sealing sheets was also significantly lower than those in fibrin sealing sheets.CONCLUSIONSThe gelatine sealing sheets are more effective than the fibrin sealing sheets in preventing surgical adhesions. These findings suggest that the gelatine sealing sheet may help prevent adhesions and thus be a therapeutically effective biomaterial in vascular surgery.  相似文献   
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