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11.
The morphological base for the impaired function of the blood retinal barrier was studied in 50 eyes of 10 insulin dependent and 21 non-insulin dependent patients with various levels of diabetic retinopathy. The permeability of the blood retinal barrier (PBRB) was determined by vitreous fluorophotometry with correction for autofluorescence, lenstransmission and non-protein bound plasma fluorescein concentration. Morphological abnormalities of diabetic retinopathy assessed by fundus photography and fluorescein angiography were individually scored on a decimal scale and related to the PBRB by multiple regression analysis. The Pbrb was not correlated to morphological abnormalities of non-proliferative retinopathy [(1) microaneurysms, (2) hard exudates, (3) soft exudates, (4) intraretinal hemorrhages, (5) fluorescein leakage, and (6) capillary closure, p > 0.3]. The PBRB was correlated to morphological abnormalities of (pre)proliferative retinopathy [(1) intraretinal microvascular abnormalities (Sirma) and (2) new vessels (Sneo): pbrb = A – B.SIRMA – C.Sneo with PBRB in nm/sec, A = 1.5 ± 0.5, B = 0.9 ± 0.2 and C = 1.7 ± 0.4, R2 = 0.65, p < 0.0001]. It can be concluded that the increased blood retinal barrier permeability in diabetic patients is mainly due to (pre)proliferative abnormalities and not to non-proliferative abnormalities.  相似文献   
12.
郑高欣 《眼科研究》1993,11(3):197-199
报告118例(133眼)由各种疾病引起的玻璃体出血机化患者的视网膜电图(ERG)检查结果,其中31例作了玻璃体手术,结果表明,ERG检查对玻璃体出血机化的患者,能客观地反映其网膜功能,并对玻璃体手术的预后有指导作用。术前ERG检查,a、b波下降越严重,视功能损害显著,术后视力的预后越差,同时证实,玻璃体机化膜是影响a、b波波幅和时间的一个因素。  相似文献   
13.
To study the inheritance and clinical picture of a new form of vitreoretinal dystrophy I examined 18 family members of a family with six generations. Seven patients, three male and four female, in three consecutive generations were observed to be affected indicating autosomal dominant inheritance. The disease was characterized by juvenile degeneration of the vitreous with detachment of the vitreous body and some floating vitreous opacities, cystoid degeneration of the peripheral retina with whitish glistening stippled areas of superficial retinal degeneration, spotty hyperpigmentation, patches of retinal atrophy with pigmentations, occasional atrophic retinal holes, and in four family members at the age of 4 to 12 years, unilateral or bilateral retinal detachment with breaks in the peripheral retina. Most patients had hyperopia with or without astigmatism. In eyes without detached retina, the disease did not show any marked progression, the lens was clear, the posterior fundus and the retinal and choroidal vessels were normal, and the visual acuity, visual fields, dark adaptation, colour vision, electroretinograms, and visually evoked response findings were normal.  相似文献   
14.
This study aimed to investigate whether T cells in aqueous humour are different in different types of uveitis and correlate with clinical phenotype. Patients with clinically different types of uveitis, but all displaying active anterior uveitis, were phenotyped and samples of aqueous humour (AH) and peripheral blood (PB) collected. Cells from AH and PB were separated by centrifugation and by density gradient centrifugation (to obtain mononuclear cells PBMC), respectively. Cells were activated with PMA and ionomycin in the presence of Brefeldin A, stained for surface markers and intracellular cytokines, and analysed by flow cytometry. The cytokine profile was correlated with the clinical phenotype. Increased percentages of interleukin (IL)-10+-, but not interferon (IFN)-gamma+ T lymphocytes were found in AH compared with PB in patients with acute anterior uveitis (AAU), FHC or chronic panuveitis (PU). There was a trend towards elevated levels of IL-10+ T cells in AH from patients with FHC compared with AH from acute uveitis and panuveitis patients. Increased levels of IL-10+ T cells in AH compared with PB were also found in samples from patients with isolated uveitis, but not those with associated systemic disease. Levels of cytokine-positive T cells were not associated with the use of topical steroids or to the severity of the anterior uveitis. While type I cytokine-producing T lymphocytes are present in AH during AU, the presence of increased proportions of IL-10+ T lymphocytes in AH from patients with uveitis may be indicative of an anti-inflammatory mechanism that may influence the type and course of ocular inflammation in these patients.  相似文献   
15.
目的:分析玻璃体切除术治疗严重增殖型糖尿病视网膜病变(PDR)的疗效。方法:PDR患者31例(35眼),在控制血糖、血压情况下行玻璃体切除术,术中均作次全或全视网膜光凝。分析手术前后及随访6~32个月的资料。结果:最后随访时,视网膜平伏,眼底清晰可见,保留一定视力的手术成功眼为29眼,最后成功率为82.9%;病变较轻组比病变重度组成功率高(P〈0.05);出血时间〉6个月组较出血时间≤6个月成功率  相似文献   
16.
Samples of aqueous fluid were obtained from 35 controls who were people undergoing routine cataract surgery. Similar samples were taken from seven patients with clinically definite multiple sclerosis (MS) and a previous history of optic neuritis, either at cataract surgery or as an elective procedure. Oligoclonal bands were found in only one subject who suffered from the MS-uveitis syndrome.  相似文献   
17.
18.
Interspecies differences in pulmonary and pleural responses to the inhalation of natural mineral and synthetic vitreous fibers have been observed in chronic and subchronic studies. However, the reasons for these differences are not clearly understood. There are also fiber-specific differences in the outcome of chronic inhalation exposure to natural mineral and synthetic vitreous fibers. Whether these differences are dependent upon the ability of these fibers to translocate to the pleural space is unknown. The present study was conducted to compare retained fiber burdens and selected pathological responses in the pleural compartments of rats and hamsters following subchronic inhalation of MMVF 10a fiberglass, a fiber negative for tumorigenesis or fibrosis in chronic studies. Fischer 344 rats and Syrian golden hamsters were exposed for 4 or 12 weeks by nose-only inhalation at nominal aerosol mass concentrations of 45 mg/m3 (610 WHO fibers/cc). Pulmonary fiber burdens and pulmonary inflammatory responses were greater in rats than in hamsters. The total number of fibers in the lung was approximately three orders of magnitude greater than in the pleural compartment. Pleural burdens in the hamster (160 fibers/cm2 surface area) were significantly greater than burdens in similarly exposed rats (60 fibers/cm2 surface area) following 12 weeks of exposure. With time postexposure, pleural burdens decreased in hamsters but were essentially unchanged in rats. Pleural inflammatory responses in both species were minimal. In rats, pleural inflammation was characterized by increased numbers of macrophages and increases in mesothelial cell replication during the period of fiber exposure. In contrast, hamsters had increased numbers of macrophages and lymphocytes, and mesothelial-cell replication indices were elevated on the parietal pleura of the costal wall and diaphragm, with some of these responses persisting through 12 weeks of postexposure recovery. Taken together, the results suggest that differences among rodent species in pleural responses to inhaled fibers are due to a delivered dose of fibers and to the biological responses to the presence of the fibers.  相似文献   
19.
中药对实验性玻璃体出血的作用观察   总被引:7,自引:4,他引:7  
观察中药对实验性玻璃体出血的治疗作用。用兔自体血造成玻璃体出血模型,并分眼血宁治疗组,空白对照组,模型对照组及尿激酶对照组,10天后观察玻璃体Fe62+,蛋白浓度和超氧化物歧化酶活性的变化。结果;玻璃体出血时玻璃体内Fe^2+和蛋白浓度升高,SOD活性下降;治疗组Fe^2+浓度明显降低,SOD活性增强。结论:眼血宁不仅能促进玻璃体出血吸收,同时对出血造成的玻璃体组织结构损害有一定促进恢复作用。  相似文献   
20.
目的:观察红参对视网膜、肾、脾动脉硬化的预防作用。方法:分3组观察家兔眼底血管病变反映全身小动脉硬化的程度。A 组为正常对照组,B 组为高血压模型组,均喂普通饲料,C 组为高血压模型组喂红参2g/d。(1)制作高血压动物模型;(2)观察视网膜、肾、脾血管在光学显微镜下的改变。结果:A 组视网膜、肾脏、脾脏血管形态和组织结构正常,B 组小动脉壁呈均质玻璃样变性,C 组血管结构基本正常。结论:红参对高血压性视网膜动脉硬化有预防作用。  相似文献   
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