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21.
A right liver graft lacking the middle hepatic vein can result in congestion of the anterior segment. We describe a method of reconstructing the middle hepatic vein tributaries by using the recipient’s own middle hepatic vein with vascular closure staples. During a living donor right liver transplantation, the middle hepatic vein tributaries draining segments V (V5) and VIII (V8) of the right lobe graft were reconstructed using the recipient’s own middle hepatic vein and secured with vascular closure staples. Computed tomography showed good venous outflow from the middle hepatic vein and no congestion or atrophy of the anterior segment of the right liver grafts. Thus, using the recipient’s own middle hepatic vein is a suitable option for reconstructing the middle hepatic vein tributaries (V8 and V5) in right-liver living donor transplantation and the application of vascular closure staples helps to accomplish this.  相似文献   
22.
To our knowledge, only a few cases of thyroid carcinoma with an extensive tumor thrombus in the atrium have been reported in literature. We describe a unique case of papillary carcinoma of the thyroid with extensive tumor thrombus in the atrium. A 74-year-old man consulted our hospital because of thyroid carcinoma with an extensive tumor thrombus in the atrium. Computed tomography (CT) revealed a 2-cm tumor with extensive continuous tumor thrombus in the left jugular vein, innominate vein, superior vena cava, and atrium. The tumor was resected to reduce the risk of sudden death from tumor embolism into the pulmonary arteries. Histologically, the diagnosis was papillary carcinoma of the thyroid. Thyroid carcinoma, especially papillary carcinoma, rarely develops a macroscopic tumor thrombus. Patients with an extensive tumor thrombus generally have poor prognoses and high mortality. This patient has been followed for 7 months after successful operation without recurrence.  相似文献   
23.
The purpose of this study was to ascertain the usefulness of preoperative evaluations of donors by computed tomography (CT) volumetry and CT cholangiography for prevention of unexpected liver failure and biliary complications after donor right hepatectomy for adult-to-adult living donor liver transplantation. Fifty-two donors who underwent right hepatectomy without the middle hepatic vein were enrolled in this study. The values of graft weight (GW) were significantly correlated with those of estimated graft volume (GV; P < 0.0001). GW was predicted by the following formula: GW = 155.25 + 0.658 x GV; r(2) = 0.489. CT cholangiography revealed anatomical variants of biliary structure in one-third of the donors and also clearly showed one or two small biliary branches from the caudate lobe to the right hepatic ducts or the confluence in 58% of the donors. Biliary leakage, which was treated by conservative therapy, occurred in only one donor (1.9%). No donors received homologous blood transfusion. Hyperbilirubinemia (serum total bilirubin >5 mg/dl) occurred in 5.8% of the donors during their early postoperative periods. Precise evaluations of liver remnant volume by CT volumetry and biliary variation by CT cholangiography are essential for performing safe donor hepatectomy, preventing hepatic insufficiency and minimizing the risk of biliary tract complications.  相似文献   
24.
PURPOSE: To elucidate the intraocular pressure (IOP)-lowering effects and associated characteristics of Y-39983, a selective Rho-associated coiled coil-forming protein kinase (ROCK) inhibitor derived from Y-27632, in animal eyes. METHODS: Y-39983 was compared with Y-27632 for selectivity of ROCK inhibition by biochemical assay. The IOP was monitored by pneumatonometer in albino rabbits and cynomolgus monkeys that were given topically administered Y-39983. The total outflow facility and uveoscleral outflow were measured by two-level constant-pressure perfusion and perfusion technique using fluorescein isothiocyanate-dextran, respectively, at 2 hours after topical administration of Y-39983 in albino rabbits. The ocular toxicologic effects of topical administration of Y-39983 were observed in albino rabbits and cynomolgus monkeys. RESULTS: A biochemical assay showed that Y-39983 inhibited ROCK more potently than Y-27632. In rabbits, topical administration of Y-39983 significantly increased conventional outflow by 65.5%, followed by significant, dose-dependent reduction in IOP. Maximum IOP reduction was 13.2 +/- 0.6 mm Hg (mean +/- SE) at 0.1% Y-39983 in rabbits. In monkeys, at 3 hours after topical administration of 0.05% Y-39983, maximum reduction of IOP was 2.5 +/- 0.8 mm Hg. No serious side effects were observed in ocular tissues except sporadic punctate subconjunctival hemorrhage during long-term topical administration of Y-39983 four times a day (at 2-hour intervals) in rabbits or monkeys. However, punctate subconjunctival hemorrhage was not observed with administration twice daily (at a 6-hour interval) or three times a day (at 5-hour intervals). CONCLUSIONS: Y-39983 causes increased outflow facility followed by IOP reduction. Y-39983 ophthalmic solution may be a candidate drug for lowering of IOP, since it increases conventional outflow and produces relatively few side effects.  相似文献   
25.
The prick test is a useful skin test for diagnosing immediate hypersensitivity response. Sometimes it is necessary to perform prick tests on patients who have already received antihistamines or corticosteroids. It is, however, occasionally uncertain whether the results of prick tests are reliable. In this study, the inhibitory effects of prednisolone (10 mg/day) and fexofenadine (120 mg/day) on the response to prick tests induced with histamine and compound 48/80 were examined. During a 7-day-continual drug administration, prick tests were performed 8 h after drug administration. The inhibitory effects of fexofenadine on both the histamine- and compound 48/80-induced skin responses were exhibited on the 1st day and persisted from 24 to 36 h after the final administration. The histamine-induced wheal responses were not inhibited by prednisolone, while the compound 48/80-induced flare and wheal responses were significantly inhibited on the 5th day of drug administration. These responses returned to the baseline level 24 h after the last drug administration. Thus, the results of skin tests performed during administration of antihistamines and corticosteroids should be carefully interpreted.  相似文献   
26.
To examine the role of calcium influx in the early phase after brief forebrain ischemia and subsequent delayed neuronal cell death in the hippocampus,45Ca autoradiography and electron microscopic cytochemistry, by a combined oxalate-pyroantimonate method, were carried out in gerbil brains after 5 min bilateral common carotid arterial occlusion. Further, neuronal during the ischemic and postischemic periods was determined by conventional or immunohistochemical staining for microtubule-associated protein 2 (MAP2) with and without calcium-entry blockers.45Ca autoradiography showed a high peak of calcium in the hippocampus at 5 min of recirculation. Electron cytochemical microscopy also demonstrated accumulation of intracellular calcium pyroantimonate deposits in the neuronal cells in all regions. At 30 min of reperfusion, amounts of calcium in the hippocampus returned to the control levels, and intracellular dense calcium pyroantimonate deposits were reduced in these areas. Loss of the reaction for MAP2 was noted in the medial CA1 of the hippocampus immediately after 5 min ischemia and at 5 and 30 min after reperfusion. MK-801 (10 mg kg−1, anN-methyl-d-aspartate (NMDA) receptor antagonist, injected intraperitoneally 1 h before ischemia, suppressed the early increase of calcium in the forebrain and neuronal cell necrosis in the CA1. However, neither injection of MK-801 30 min after reperfusion nor preischemic treatment with 0.5 mg kg−1 Nicardipine, voltage-sensitive calcium channel antagonists, prevented neuronal death. In immunohistochemical staining for MAP2, the ischemic lesion in the medial CA1 maintained after 5 min ischemia and the subsequent early reperfusion period in the untreated brains was protected by the preischemic injection of 10 mg kg−1 MK-801, but was not restored by the injection of 0.5 mg kg−1 Nimodipine or 1 mg kg−1 Nicardipine. In conclusion, it is suggested that an early excess of calcium influx could be caused mainly by excitatory amino acid overload through NMDA receptor-mediated calcium channels during the ischemic and early postischemic periods.  相似文献   
27.
28.
Background We developed and evaluated the clinical usefulness of a scoring system that subclassified type Vi pit patterns. Methods We studied 119 colon cancer lesions (pTis, n = 26; pT1, n = 93) and 22 tubular adenoma lesions with severe atypia in which a type Vi pit pattern was visible under a stereomicroscope. Four type Vi pit pattern formation appearances (existing pits, marginal irregularities of the gland duct, narrowing of the gland duct lumen, and unclear outline of the gland duct) were defined, and the relationship between each appearance and the invasive depth of the cancer was evaluated. Results When the four type Vi pit pattern appearances were considered in a logistic regression analysis, the odds of a more invasive submucosal cancer were significantly increased by the appearance of marginal irregularities, a narrowed lumen, and an unclear outline. In the logistic regression analysis results, when 0.63 was used as the cutoff score for prediction of a more invasive submucosal cancer, 80 cases in the less invasive group were classified correctly (specificity, 1.0), whereas 53 (86.9%) of the 61 cases in the more invasive group were classified correctly (sensitivity, 0.869). Conclusions It is important first to understand the usability and limitations of objective scoring of type V pit pattern findings and then to apply this score to the determination of cancer depth in order to accurately identify lesions suitable for endoscopic treatment.  相似文献   
29.
The reaction of O2 with a Ru13@Pt42 core–shell particle consisting of a Ru13 core and a Pt42 shell was theoretically investigated in comparison with Pt55. The O2 binding energy with Pt55 is larger than that with Ru13@Pt42, and O–O bond cleavage occurs more easily with a smaller activation barrier (Ea) on Pt55 than on Ru13@Pt42. Protonation to the Pt42 surface followed by one-electron reduction leads to the formation of an H atom on the surface with considerable exothermicity. The H atom reacts with the adsorbed O2 molecule to afford an OOH species with a larger Ea value on Pt55 than on Ru13@Pt42. An OOH species is also formed by protonation of the adsorbed O2 molecule, followed by one-electron reduction, with a large exothermicity in both Pt55 and Ru13@Pt42. O–OH bond cleavage occurs with a smaller Ea on Pt55 than on Ru13@Pt42. The lower reactivity of Ru13@Pt42 than that of Pt55 on the O–O and O–OH bond cleavages arises from the presence of lower energy in the d-valence band-top and d-band center in Ru13@Pt42 than in Pt55. The smaller Ea for OOH formation on Ru13@Pt42 than on Pt55 arises from weaker Ru13@Pt42–O2 and Ru13@Pt42–H bonds than the Pt55–O2 and Pt55–H bonds, respectively. The low-energy d-valence band-top is responsible for the weak Ru13@Pt42–O and Ru13@Pt42–OH bonds. Thus, the low-energy d-valence band-top and d-band center are important properties of the Ru13@Pt42 particle.

In this theoretical study by DFT computations, characteristic features of the Ru13@Pt42 core–shell particle in O2 activation are clearly discussed in comparison with Pt55.  相似文献   
30.
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