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81.
G. HARSTEN K. PRELLNER J. HELDRUP O. KALM R. KORNFÄLT 《Acta paediatrica (Oslo, Norway : 1992)》1990,79(4):402-409
ABSTRACT. Respiratory tract infections (RTIs) in small children account for a considerable proportion of health care expenditure. In 113 children, followed for the first three years of life, we studied the frequency of acute RTI and its relationship to the factors: type of day-care, age, sex, family size, living conditions, allergic predisposition, family smoking habits, and season. To elucidate the influence of age, the frequency of acute RTI and its relationship to type of day-care was longitudinally studied on a quarterly basis. The frequency of acute RTI diagnosis increased gradually from birth culminating in a peak at the beginning of the second year. Besides age and season, type of day-care was the only factor studied to show any relationship with the frequency of acute RTI diagnosis. Up to the age of almost 2 1/2 years, children attending day-care centres accounted for more RTI diagnoses than did those in home care or family day-care, categories with comparable frequncies. 相似文献
82.
A Fornasieri S Tazzari M Li S Armelloni LT Tarelli A Sessa G D'Amico 《American journal of kidney diseases》1998,31(3):435-442
Cryoglobulinemic glomerulonephritis is particularly frequent in type II mixed IgMk-IgG cryoglobulinemia. The typical form is a membranoproliferative glomerulonephritis with a particular monocyte infiltration. In the most severe cases, there is occlusion of the capillary lumina by the same immunoglobulin constituents of the cryoprecipitate. While it is generally accepted that the "hyaline thrombi" are endoluminal aggregates of IgG-IgM immune complexes, probably favored by high endocapillary concentration of cryoglobulins, the modality of generation has not been studied. To study the dynamic formation of such "thrombi," we reproduced an experimental model of cryoglobulinemic glomerulonephritis in mice by injecting them twice a day for 3 days with 4 mg human IgMk-IgG cryoglobulins previously solubilized at 37 degrees C. The dynamic formation of immunodeposits was studied by immunofluorescence and electron microscopy. After 1 day, only mesangial deposits were found; after 3 days, in addition to mesangial deposition, all the capillary lumina were occluded by huge electron-dense bodies. To look for and quantify the contacts between such "thrombi" and mesangial or subendothelial deposits, we obtained serial, ultrathin, 0.5-microm sections that allowed us to reconstruct the whole glomerular tuft. Within each serial section, there was continuity between hyaline thrombi and mesangial or subendothelial deposits ranging from 80% to 85% of the capillary loops. The percentage was 100% for two adjacent serial sections. In conclusion, our data demonstrate directly for the first time that hyaline thrombi follow mesangial deposits. The high percentage of contacts between thrombi and mesangial or subendothelial deposits suggests that they result from in situ build-up of true huge endoluminal immunodeposits after saturation of the clearance capacity of the mesangium. 相似文献
83.
蒙医诊断学是具有较强理论性和实践性的学科,这一特点要求我们在蒙医诊断学的教学方法上,既要重视理论教学,又要重视临床教学;既要传授知识,又要培养实际动手能力。 相似文献
84.
Male white Wistar rats (250–300 g), after an overnight fast, were treated with a crude extract (20 mg/kg oral) from the leaves of E. drupifera . The extract was administered 2 h before and 2 h after either an oral glucose load (3 g/kg) or a subcutaneous injection of adrenaline (0.01 mg/kg). The results showed that the extract reduced the blood glucose levels in rats that received the extract 2 h before glucose and adrenaline administration by about 34.3% and 35.2%, respectively. For the group that received the extract 2 h after glucose and adrenaline administration, the blood glucose levels were reduced by about 52.8% and 29.7%, respectively. Comparison was made between the action of the extract and a known hypoglycaemic drug — glibenclamide (0.29 mg/kg oral). The extract (20 mg/kg oral) was found to be faster and more effective than glibenclamide in lowering the blood glucose levels in fasting rats. 相似文献
85.
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87.
Prevalence of HLA sensitization in female apheresis donors 总被引:3,自引:0,他引:3
BACKGROUND: Transfusion-related acute lung injury (TRALI) is a serious complication of plasma-containing blood components. Studies have implicated HLA antibodies along with biologically active lipids in stored blood in the pathogenesis of TRALI. It has been proposed that the exclusion of HLA-untested, multiparous donors of plasma-rich components, including plasma and single-donor apheresis platelets, would substantially reduce the risk of TRALI. STUDY DESIGN AND METHODS: To investigate the feasibility of such an exclusion, 332 female plateletpheresis donors with a record of over 9000 donations, none of which were associated with TRALI, were studied. RESULTS: Seventeen percent of female donors demonstrated HLA sensitization. Parity and HLA sensitization were significantly correlated (p<0.0001), with sensitized donors having an average of 2.9 (+/− 0.6 95% CI) prior pregnancies and unsensitized donors having an average of 1.8 (+/− 0.2 95% CI) prior pregnancies. The percentage of HLA-sensitized women with 0, 1 to 2, and > or = 3 pregnancies was 7.8, 14.6, and 26.3, respectively. CONCLUSION: These findings confirm the hypothesis that multiparous women (> or = 3 pregnancies) represent an increased potential risk for TRALI. However, the exclusion of multiparous plateletpheresis donors would eliminate one-third of our female donor pool. Screening such donors for HLA sensitization may represent the optimal approach for identifying donors at risk for causing TRALI, but this still would result in the deferral of 8 percent of female plateletpheresis donors. At present, prospective screening to identify donors at risk for causing TRALI is not justified. 相似文献
88.
Objective. To determine if a single mailing from the local volunteer fire department can increase the number of homes with proper, visible address numbering. Proper numbering is essential in rapidly locating a house during an emergency response. Methods. The study was conducted at a suburban/rural fire department providing EMS andfire suppression services to a 22 square mile area with residential mailboxes located at the street. During a hazard identification pre-plan tour, each house was examined andassigned a classification: (A) No number visible on the house or mailbox (improper); (B) Number on only one side of the mailbox (improper); (C) Number on both sides or the end of the mailbox, or visible on the house (proper). The homeowners of all residences with improper numbering (A or B) were sent a one-page letter, discussing the need for proper numbering. The tour was repeated six weeks later to determine whether deficiencies had been corrected. It was prospectively determined that a 25% improvement was sought. Results. During the pre-plan tour, 73 houses were classified as type A, 454 as type B, and1706 as type C. At the re-visit, 135 (26%) of the type A andB homes had been properly numbered. Correction of deficiencies was better at type A homes (37, or 51%) than at type B homes (98, or 22%) (p < 0.001 by Chi-square). Conclusion. For houses with improper numbering, a single mailing from the fire department can be effective in encouraging residents to post proper numbers. 相似文献
89.
马缨丹叶的化学成分研究 总被引:3,自引:0,他引:3
自马缨丹(Lantana camara L.)叶中分离到六个化合物。经光谱(UV,IR,MS,1HNMR,13CNMR)和化学分析,分别鉴定为齐墩果酮酸(oleanonic acid,Ⅰ),马缨丹甲素(lantadene A,Ⅱ),马缨丹乙素(lantadene B,Ⅲ),lantanilic acid(Ⅳ),icterogenin(Ⅴ)和4′,5-二羟基-3,7-二甲氧基黄酮-4′-O-β-D-吡喃葡萄糖甙(4′,5-dihydroxy-3,7-dimethoxyflavone-4′-O-β-D-glucopyranoside,Ⅵ)。Ⅵ是新化合物,命名为马缨丹黄酮甙(camaroside)。 相似文献
90.
Simulated pulmonary nodules: detection with dual-energy digital versus conventional radiography 总被引:9,自引:0,他引:9
Niklason LT; Hickey NM; Chakraborty DP; Sabbagh EA; Yester MV; Fraser RG; Barnes GT 《Radiology》1986,160(3):589-593
Performance of a prototype dual-energy digital chest radiography unit in detecting calcified and noncalcified simulated pulmonary nodules was compared with that of a highly optimized, conventional system. Nodules ranging in size (0.5, 1.0, and 1.6 cm), in number (five to 11), and in calcium content (0-25 mg) were superimposed over the lungs of a frozen, unembalmed, human chest phantom. For each technique, six observers examined 50 posteroanterior projections with different randomized nodule locations. Detection consisted of locating and assigning a level of confidence to each perceived nodular opacity. The resulting plots of the true-positive fraction versus the mean number of false-positive calls per projection indicate that for both calcified and noncalcified nodules, the digital unit performed significantly better (P less than .01). 相似文献