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排序方式: 共有248条查询结果,搜索用时 15 毫秒
31.
双嘧达莫在汞电极上的电化学行为和吸附性质   总被引:2,自引:0,他引:2  
曾向群  林树昌  胡乃非 《药学学报》1994,29(11):856-861
在NaOH底液中,双嘧达莫在汞电极上有一不可逆的线性扫描还原峰,EPC=—1.39V(vs饱和Ag/AgCl)。该峰具有明显的吸附性。当搅拌富集时间较长、双嘧达莫的浓度较小、扫描速度较快时,电极反应几乎完全为吸附态的双嘧达莫所控制。选相交流伏安等实验表明,吸附型体为双嘧达莫中性分子。测得该体系的电子转移数n为4,不可逆吸附的αnα值为1.72。探讨了双嘧达莫的电极反应机理,建立了用吸附伏安法测定双嘧达莫的最佳条件。  相似文献   
32.
A higher incidence of sudden cardiac death among soccer spectators has repeatedly been described. Male spectators with known coronary heart disease in particular seem to be at risk of sudden cardiac death while watching a soccer match. This study was initiated to gather further information about this subgroup of visitors to a soccer stadium with an elevated risk of sudden cardiac death. A total of 2,500 spectators of a German premier league soccer match received a questionnaire at the entrance to a soccer stadium, containing questions about gender, age, medical history of coronary heart disease, prior myocardial infarction and cardiovascular risk factors. Of these, 2,431 spectators completed the questionnaire, 1,749 men and 682 women with a mean age of 38.3±13.9 years. Among the respondents, 114 (4.7%) had a medical history of coronary heart disease, including 58 (2.4%) with a prior myocardial infarction; 794 (32.7%) said that they were smokers, 326 (13.3%) had a medical history of elevated blood pressure, and 204 (8.4%) had a medical history of elevated cholesterol level. There are obviously several thousands of soccer fans with an elevated risk of sudden cardiac death in a soccer stadium, emphasizing the need for further preventive measures.  相似文献   
33.
BackgroundThe aim of the project was to identify risk factors associated with visual progression and treatment indications in pediatric patients with neurofibromatosis type 1 associated optic pathway glioma (NF1-OPG).MethodsA multidisciplinary expert group consisting of ophthalmologists, pediatric neuro-oncologists, neurofibromatosis specialists, and neuro-radiologists involved in therapy trials assembled a cohort of children with NF1-OPG from 6 European countries with complete clinical, imaging, and visual outcome datasets. Using methods developed during a consensus workshop, visual and imaging data were reviewed by the expert team and analyzed to identify associations between factors at diagnosis with visual and imaging outcomes.ResultsEighty-three patients (37 males, 46 females, mean age 5.1 ± 2.6 y; 1–13.1 y) registered in the European treatment trial SIOP LGG-2004 (recruited 2004–2012) were included. They were either observed or treated (at diagnosis/after follow-up).In multivariable analysis, factors present at diagnosis associated with adverse visual outcomes included: multiple visual signs and symptoms (adjusted odds ratio [adjOR]: 8.33; 95% CI: 1.9–36.45), abnormal visual behavior (adjOR: 4.15; 95% CI: 1.20–14.34), new onset of visual symptoms (adjOR: 4.04; 95% CI: 1.26–12.95), and optic atrophy (adjOR: 3.73; 95% CI: 1.13–12.53). Squint, posterior visual pathway tumor involvement, and bilateral pathway tumor involvement showed borderline significance. Treatment appeared to reduce tumor size but improved vision in only 10/45 treated patients. Children with visual deterioration after primary observation are more likely to improve with treatment than children treated at diagnosis.ConclusionsThe analysis identified the importance of symptomatology, optic atrophy, and history of vision loss as predictive factors for poor visual outcomes in children with NF1-OPG.  相似文献   
34.
转录因子T-bet与哮喘大鼠气道炎症及川芎嗪的干预效应   总被引:1,自引:0,他引:1  
目的:转录因子T-bet在支气管哮喘的发病中起重要作用,川芎嗪治疗哮喘有效。实验拟观察川芎嗪对哮喘大鼠气道炎症的影响和转录因子T-bet的调控作用。方法:实验于2005-11/2006-06在南京医科大学完成。①实验材料及分组:72只SPF级SD大鼠随机分为正常对照组、哮喘模型组、川芎嗪小剂量组(20mg/kg)、川芎嗪中剂量组(40mg/kg)、川芎嗪大剂量组(80mg/kg)和地塞米松组,每组12只。实验用磷酸川芎嗪注射液为丽珠集团利民制药厂生产)。②实验过程及评估:以卵蛋白腹腔注射并雾化吸入制备大鼠哮喘模型,末次雾化后24h内麻醉后处死大鼠。观察6组大鼠肺组织形态学变化;测定支气管壁厚度、支气管平滑肌厚度、嗜酸粒细胞和淋巴细胞数。采用免疫组织化学半定量法测定肺组织T-bet蛋白的表达;进行转录因子T-bet蛋白表达量与气道炎症的相关性分析。实验过程中对动物处置符合动物伦理学标准。结果:①哮喘模型组嗜酸粒细胞、淋巴细胞、支气管壁厚度和支气管平滑肌厚度,明显高于正常对照组相应指标(P均<0.01);与哮喘模型组比较,川芎嗪小、中、大剂量组和地塞米松组上述4项指标均减少(P均<0.01)。②哮喘模型组、川芎嗪小、中、大剂量组和地塞米松组的T-bet表达量低于正常对照组(P均<0.01);与哮喘模型组比较,川芎嗪小、中、大剂量组T-bet表达量增加(P均<0.01);随着川芎嗪剂量增加,T-bet表达量亦相应增加,川芎嗪小、中、大剂量组之间两两比较,差异均有统计学意义(P均<0.01)。③相关分析显示哮喘模型组T-bet蛋白表达量与嗜酸性粒细胞和淋巴细胞浸润数呈负相关(r=-0.81,-0.85,P<0.01),与支气管管壁厚度和支气管平滑肌厚度呈负相关(r=-0.77,-0.79,P<0.01)。结论:支气管哮喘大鼠存在T-bet低表达;川芎嗪可抑制气道炎症,增加转录因子T-bet蛋白的表达,纠正Th1/Th2失衡,从而治疗支气管哮喘。  相似文献   
35.
The use of automated external defibrillator (AED) by persons other than paramedics and emergency medical technicians is advocated by several US- and European organizations. However, at the present time it is still unclear to identify public places with a high incidence of out-of-hospital cardiac arrest. There are few data on the potential impact of public access defibrillators on survival after out-of-hospital cardiac arrest in sporting arenas or water parks. Therefore, we studied prospectively incidence of out-of-hospital cardiac arrest in the LAGO-die Therme in Herne. This is one of the most important swimming parks in Europe and member of the European Waterpark Association EWA. Eight AEDs were placed in the waterpark LAGO-die Therme. The locations where the defibrillators were stored were chosen to make possible a target interval of 60 seconds from collapse to first defibrillation. Twenty waterpark officers were instructed in cardiopulmonary resuscitation and in the use of the AED. During November 16, 2001 and December 31, 2004, 2.05 Mio. visitors were counted in the LAGO. Out-of-hospital cardiac arrest occurred in none of them. AED were used in two visitors with non arrhythmogenic syncope, no shock was delivered. Questionaires were done in 588 visitors (336 males, 252 females, mean age 38+21 years) in 2002 and in 579 visitors (322 males, 257 females, mean age 37+/-25 years) in 2004. In 2002, 77% of the visitors noticed the AED and, therefore, 49% performed more sporting activities. In addition, in 2004, AED was noticed by 480 visitors (83%) and 277 visitors (48%) did more sporting activities. There were no significant differences between 2002 and 2004 (p=ns). Despite no out-of-hospital cardiac arrest in the waterpark during the 3 year follow- up, it seems reasonable to install AED in sporting places with thousands of visitors per year.  相似文献   
36.
There is uncertainty in ophthalmology concerning the quality and spectral transmission of light of so-called blue filter intraocular lenses (IOL). Clinical users have noticed that such IOL's appear to have different color intensities. The discussion on medical changes by means of such IOL's is dependent on the real light transmission of these IOL's. To add some objective data we compared these IOL's by systematic transmission measurements and observed technical differences of diffraction and geometry as well as transmission differences. The result gives objective indications that differences between blue filter IOL's from different manufacturers are important and are detailed in this paper.  相似文献   
37.
38.
PURPOSE: To improve the quantification of damage to the ocular surface, metabolite levels, electrolyte concentrations, and enzyme activities were assayed in corneal epithelium, stroma and tears. METHODS: In rabbits, rinsing or contact lenses were used to induce microtrauma. For more severe trauma, experimental injuries were induced with 1 N NaOH. Human accidents included epithelial lesions and mild chemical burns. Enzymatic test systems and electron dispersive X-ray analyses (EDXA) were employed. Corneal hydration was assessed by wet and dry weights. Interleukins were analysed with ELISA. RESULTS: In contrast to normal eyes, in ocular surface trauma the interaction between tear fluid and cornea played an important part. After wearing contact lenses or rinsing, glucose and lactate levels in the cornea and in tears increased, and ATP and glycogen in the cornea decreased. After epithelial lesions, N-acetylglucose aminidase (NAcGA, E.C.3.2.1.50) was released into the tears. Epithelial defects alone and--much more--rinsing the denuded stromal surface produced an increase of lactate and glucose in tears and a dramatic fall in Na, Cl, and S levels in the stroma. Rinsing with phosphate induced corneal calcification. IL-1 and IL-6 were increased in human corneal buttons from patients with trauma and inflammation. CONCLUSIONS: Biochemical analyses may be useful to quantify trauma to the ocular surface.  相似文献   
39.
PURPOSE: To report the use of perfluorohexyloctane, a liquid semifluorinated alkane that is heavier than water, as an internal tamponade agent in surgery for complicated retinal detachments. DESIGN: A consecutive interventional case series from three study centers. METHODS: In 23 consecutive eyes (23 patients, 19 men and four women, mean +/- standard deviation (SD) age of 58.5 years +/- 16.1) perfluorohexyloctane was used for long-term internal tamponade. Included were eyes with complicated retinal detachment involving the lower two quadrants of the fundus. Excluded were patients with diseases in the fellow eye or severe systemic disease. A pars plana vitrectomy was performed, including membrane peeling and retinotomy where necessary. RESULTS: The mean duration for perfluorohexyloctane being left in situ was 76 days (SD 37.64) (range, 35-202 days). Four weeks following the removal of perfluorohexyloctane 19 of the 23 patients had total reattachment of the retina; three eyes had a recurrence of retinal detachment. One patient was lost to follow-up. The mean follow-up after perfluorohexyloctane removal was 97 days (range, 48 to 169 days). Cataract formation or progression was noted in nine of the 10 eyes. There were two cases with high intraocular pressures. Dispersion into small droplets was observed as early as 3 days postoperatively in three of the 23 patients. At least 12 of the 23 patients had an obvious dispersion by the time of perfluorohexyloctane removal. There was no sign of optic atrophy, retinal necrosis, or retinal vascular occlusion. CONCLUSION: Perfluorohexyloctane was tolerated as a long-term internal tamponade agent without obvious signs of damage to the retina or optic disk. Of all the complications noted, the most common was that of dispersion of the perfluorohexyloctane bubble into droplets.  相似文献   
40.
Becker  CD; Quenville  NF; Burhenne  HJ 《Radiology》1988,167(1):63-68
Recurrent cholelithiasis must be expected after gallstone removal without cholecystectomy. Chemical gallbladder ablation may offer prevention but requires preliminary cystic duct occlusion. Radio-frequency (RF) electrocoagulation of the cystic duct was performed in 15 pigs to induce occlusion by a controlled thermal epithelial injury. A flexible coagulation catheter was placed into the cystic duct lumen under fluoroscopic control by means of either subhepatic cholecystostomy or direct, percutaneous transhepatic gallbladder puncture. Complete cystic duct occlusion was proved in 14 animals. Follow-up ranged from 1 to 17 weeks (mean, 11 weeks). Histologically, the RF technique induced an intense chronic inflammatory and fibroblastic reaction, which eventually obliterated the coagulated cystic duct segments. There was no epithelial regeneration or recanalization of the fibrotic cystic duct segments. The adjacent structures, particularly the cystic artery, were intact in all specimens.  相似文献   
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