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991.
We encountered a late pulmonary complication after umbilical cord blood transplantation (UCBT) that has not been previously reported. High-resolution CT (HRCT) findings of this disease were compared with the pathology. HRCT obtained on inspiration showed dilated thick-walled bronchioli, and innumerable centrilobular linear and branching structures in the bilateral middle and lower lobes. Neither mosaic perfusion nor air-trapping was seen in HRCT on inspiration and expiration. These HRCT findings were atypical compared with those of former bronchiolitis obliterans (BO) after bone marrow transplant (BMT). Pathologic specimens obtained by open lung biopsy showed thickening of the wall from the distal bronchioli to the alveolar ducts due to submucosal and intraepithelial infiltration of lymphocytes, histiocytes and foamy macrophages, which was not accompanied by organizing changes. These changes resemble lymphocytic bronchiolitis in lung transplant recipients, which was well correlated with HRCT findings. We think that our case was a new late pulmonary complication after UCBT.  相似文献   
992.
993.
994.
Few researchers have conducted 24-hour total heart beat (THB) studies in patients with bradycardia, and its prevalence and significance in the elderly remain controversial. The aim of this study was to compare of distribution of THB, underlying diseases and effects of medication on THB in inpatients with bradycardia less than 80,000 beats/24 hrs between elderly and young patients. There were 303 Holter monitorings of bradycardia out of 7,687 consecutive monitorings, with only the earliest monitoring registered when duplicating. The age distribution of these 303 patients with bradycardia showed a two-peak pattern: a large peak at age 65-70 and a small peak at age 15-20. Thus we divided them into a young group aged under 65 (194 patients: mean 49.1) and an elderly group aged 65 or more (109 patients: mean 71.0). There was no difference in mean THB or distribution of THB between the two age groups, irrespective of medication which had a side effect of bradycardia. Underlying diseases included three bradyarrhythmias; such as sinus bradycardia, sick sinus syndrome and II or III degree AV block, long QT syndrome, ischemic heart disease, cardiomyopathy, valvular disease and others. There was no difference in mean THB or distribution of THB between the two age groups in each disease group. Moreover, with respect to bradyarrhythmias, there was a small distribution of THB between 75,000 and 70,000 beats/24 hrs in patients without medication while there was a sparse distribution of THB in patients with medication.  相似文献   
995.
A previously healthy 57-year-old woman with peripheral edema and exertional dyspnea had diminished right breath sounds and edema of both legs. Chest radiography showed massive right pleural effusion, and abdominal computed tomography showed ascites. During cardiac catheterization, pressure curves of both ventricles showed "dip-and-plateau" patterns. We diagnosed constrictive pericarditis and conducted pericardiectomy. During surgery, we found a thick fibrous pericardium surrounding the entire heart and a band of calcium in the atrioventricular groove. Histological examination of excised pericardial tissue showed fibrosis, hyalinization, and calcification, with thickening of < or = 18 mm. Cases of localized pericardial thickening, including constricting bands in the atrioventricular groove, are rare and many such complications occur postoperatively. We report a rare case of primary constrictive pericardial band resulting in massive right pleural effusion and ascites.  相似文献   
996.
Cannulation of the abdominal aorta in organ donors with advanced arteriosclerotic disease or extensive trauma may be problematic owing to difficulty in securing a watertight tie around the diseased aorta, the danger of creating a false passageway in the aorta, and the risk of breaking off plaque particles that can advance into the arteries of donated organs. Cannulation problems can be avoided in these challenging donors by using a simplified technique for cannulation of the thoracic aorta in which a Foley catheter is passed down around the aortic arch, the balloon is inflated, and cool flushing is initiated.  相似文献   
997.
BACKGROUND: Posttransplant Epstein-Barr virus-associated B-cell lymphoproliferative disease (PTLD) has a higher incidence after intestinal transplantation than after transplantation of other solid organs and is associated with a high mortality. A new anti-CD20 monoclonal antibody, rituximab, has shown efficiency in the treatment of B-cell lymphoma, including PTLD, but its use has not yet been reported in intestinal transplant recipients. METHODS: We retrospectively reviewed five patients who were diagnosed with PTLD from March 1999 to August 2001, after intestinal transplantation. These patients were primarily managed with rituximab, associated with reduction or interruption of immunosuppression and antiviral therapy with ganciclovir and cytomegalovirus immune globulin. Rituximab was administered at weekly doses of 375 mg/m until full remission was ascertained, and the interval between doses was then increased. No patient received chemotherapy. RESULTS: One patient had nonmalignant lymphoproliferation, and four had malignant PTLD, as assessed by histopathology and monoclonality of the tumor. Two pediatric patients had severe generalized disease. All patients had received OKT3 as treatment of rejection before developing PTLD. All tumors showed proliferation of CD20 cells and were positive for Epstein-Barr virus by in situ hybridization. All patients responded to rituximab therapy and have achieved full remission with a follow-up of 3 to 30 (median, 8) months. CONCLUSION: Prolonged rituximab treatment, in association with reduction of immunosuppression and antiviral therapy, is highly efficient as part of the first-line treatment of CD20 B-cell PTLD after intestinal transplantation.  相似文献   
998.
999.
Calprotectin is a calcium- and zinc-binding protein complex that is abundant in cytosol of neutrophils. The concentration of calprotectin in extracellular fluids is greatly increased under various inflammatory conditions in vivo. We recently demonstrated that calprotectin inhibited cell growth and induced apoptosis of various cell types including tumor cells and normal fibroblasts; therefore, extracellular calprotectin might cause tissue destruction in severe inflammatory diseases. We previously found that an alkaloid, lycorine inhibits induction of apoptosis by calprotectin. In this paper, we examined the inhibitory activities of other Amaryllidaceae alkaloids, namely, lycoricidinol, hippeastrine and ungerine against the cytotoxicity of calprotectin. Lycoricidinol (narciclasine) inhibited calprotectin-induced cytotoxicity at more than 10-fold lower concentration (IC50=0.001-0.01 microg/ml) than lycorine, while the effects of the latter two alkaloids were very weak. Therefore, we next checked the prophylactic effect of lycorine and lycoricidinol on the adjuvant arthritis model in rats. Lycoricidinol, but not lycorine, significantly suppressed the degree of swelling of adjuvant-treated as well as untreated feet, suggesting that lycoricidinol might be a candidate as a the drug having marked suppressive activity for inflammation which might be influenced by calprotectin.  相似文献   
1000.
In our two-stage model of rat urinary bladder carcinogenesis employing N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) as the initiator, sodium L-ascorbate (Na-AsA) exhibits dose-dependent promotion. In the present study, in order to assess the possible reversibility of the promoting effects, we investigated how different administration periods of Na-AsA influence its promoting activity. In experiment 1, rats were treated with 5% Na-AsA for different administration periods with or without withdrawal and injected with 5-bromo-2'-deoxyuridine (BrdU) to allow determination of the cell proliferation status. Replicative DNA synthesis in the urinary bladder epithelium was shown to return to normal after removal of the promoting stimulus. In experiment 2, rats were initially given BBN for 4 weeks and subsequently received 16 weeks of Na-AsA, alternating with basal diet, at intervals of 4, 8 or 16 weeks, within total 32-week period. The longer the continuous exposure to Na-AsA, the greater the yield of papillomas and carcinomas in the urinary bladder. In experiment 3, Na-AsA was given for 4 or 8 weeks after BBN initiation and the animals were killed at weeks 8 and 12. Both promotion of lesion development and increase of DNA synthesis in the urinary bladder epithelium were dependent on the length of exposure to Na-AsA and the total period of exposure. The results indicate that the promoting effects of Na-AsA in urinary bladder carcinogenesis are reversible to certain extent after its withdrawal, and the existence of cumulative exposure time threshold seems likely.  相似文献   
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