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31.
The limitations of keratometry and photokeratoscopy are briefly discussed. A new photogrammetric technique of measuring corneal topography is described. Contours and cross-sections of abnormal corneas are presented to illustrate the scope and application of the new technique.  相似文献   
32.
目的 探讨翼状胬肉切除术后并发角膜溃疡的危险因素。方法 选取2017年5月—2022年3月在青岛市中医医院行翼状胬肉切除术的患者153例,统计术后角膜溃疡发生情况,将并发角膜溃疡的患者作为发生组,其余作为未发生组。比较两组患者一般资料,采用多因素Logistic逐步回归模型分析翼状胬肉切除术后并发角膜溃疡的危险因素。结果 153例行翼状胬肉切除术的患者,术后30例并发角膜溃疡作为发生组,其余123例作为未发生组。与未发生组比较,发生组糖尿病、复发性翼状胬肉、手术操作不规范、角膜缝线松动及激素类药物应用不合理的构成比升高(P <0.05)。多因素Logistic逐步回归分析结果显示,糖尿病[OR=2.678(95%CI:2.013,3.343)]、复发性胬肉[OR=2.280(95%CI:1.659,2.900)]、手术操作不规范[OR=7.036(95%CI:4.152,9.919)]、角膜缝线松动[OR=3.466(95%CI:2.632,4.300)]及激素类药物应用不合理[OR=5.217(95%CI:3.021,7.414)]均是翼状胬肉切除术后并发角膜溃疡的危险因素(P...  相似文献   
33.
Problems associated with the use of 5-iodo-2-deoxyundine (IDU) in the treatment of herpes simplex keratitis can be attributed largely to the polar nature of IDU resulting in its poor permeability across the lipoidal epithelial layer of the corneal membrane. Five aliphatic 5-esters of IDU were synthesized and evaluated as prodrugs for potential use in the treatment of deep ocular infections such as stromal keratitis, iritis, and even retinitis. A parabolic relationship between in vitro corneal membrane permeability and carbon chain length of prodrugs is evident. For a given prodrug, enzymatic hydrolysis proceeded most readily in iris–ciliary body, followed by cornea and aqueous humor. An increase in carbon chain length made the prodrugs more enzymatically labile but more resistant to chemical hydrolysis at pH 7.4 and 34°C. The 5-butyryl ester of IDU exhibited an approximately fourfold increase in aqueous humor IDU concentration relative to IDU at 25 min following instillation of 25-µl 5 mM solutions.  相似文献   
34.
正视眼角膜表面形态和屈光力分析   总被引:2,自引:0,他引:2  
目的:为探讨正视眼角膜表面形态和屈光力。方法:83只正视眼用TomeyTMS-2TM型角膜地形图检查角膜表面形态和屈光力。结果:①绝对等级全角膜有2~5种颜色,屈光力有轻微的变化;②角膜中央屈光力为43.854±1.321D,Simk值为44.142±1.342D,平均屈光力(ACP)为43.007±1.473D,角膜表面规则系数(SRI)为0.241±0.213,角膜表面不对称系数(SAI)为0.321±0.130,不规则散光指数(IAI)为0.357±0.006。结论:本文检查的国人正视眼角膜表面形态和屈光力数值,可为屈光性角膜手术提供解剖依据。  相似文献   
35.
异种脱细胞角膜基质囊袋移植的生物相容性研究   总被引:2,自引:0,他引:2  
目的探讨脱细胞猪角膜基质移植入兔角膜囊袋后的生物学反应。方法猪角膜通过不同方式去除细胞及免疫源性成分,保留角膜组织基质的弹力纤维及胶原纤维,将其切取为直径为4mm的植片,植入兔角膜囊袋内,在不同时间点观察生物材料在角膜内生物学反应。结果材料植入兔角膜囊袋3个月,生物相容性良好,材料逐渐降解,材料内有胶原和角膜基质细胞长人。结论新型可降解角膜基质材料植入后未见兔角膜有明显的炎症反应,材料的组织相容性好,可作为组织工程角膜的支架材料。  相似文献   
36.
In nephropathic cystinosis, corneal cystine crystals cause severe photophobia and corneal erosions. Topical cysteamine dissolves these crystals, but cannot be marketed because it rapidly oxidizes to the disulfide form, cystamine, at room temperature. Since cystamine itself could be used commercially, we compared the efficacy of cystamine and cysteamine with respect to cystine crystal dissolution in a randomized, double-masked clinical trial. One eye each of 14 patients with cystinosis was randomized to either cystamine or cysteamine, 0.5%, with 0.01% benzalkonium chloride; the companion eye was treated with the alternate preparation. Corneal crystals were photographed and a density score was assigned to each slide based on 13 standard slides. After 8–20 months, 6 patients showed significant reduction of the corneal crystal score in only one eye. In each case, the improved eye was the cysteamine-treated eye. Theoretically, cysteamine should dissolve both intracellular and extracellular crystals, whereas cystamine should dissolve only intracellular crystals because it must first be reduced to the free thiol by the cytoplasmic-reducing environment. Hence, the lack of efficacy of the disulfide cystamine suggests that some corneal cystine crystals in cystinosis patients are extracellular, and that another form of stable, topical cysteamine must be developed for cystinosis patients.  相似文献   
37.
角膜缘干细胞移植治疗兔眼表碱烧伤的实验研究   总被引:6,自引:1,他引:6  
目的 :探讨眼表碱烧伤后行角膜缘干细胞移植术的疗效 ,并与单纯行角膜移植术组作比较。方法 :在 16只兔双眼上制作碱烧伤模型 ,1d后 ,右眼行异体板层角膜缘干细胞移植术 ,左眼行异体板层角膜移植术 ,术后观察 6月 ,根据术眼的角膜新生血管分级、植片的混浊度、水肿度来计算移植排斥反应指数 (RI) ,以RI值判断植片的存活情况。结果 :行异体板层角膜缘干细胞移植术的 16眼中有 14眼RI <9,治愈率达 87.5 % ;行单纯异体板层角膜移植的 16眼中 6眼RI值 <9,有效率 3 7.5 % ;两者相比有显著性差异 (P <0 .0 0 1)。两组的新生血管数、植片的混浊度、水肿度及RI值均有显著性差异。结论 :含干细胞的异体角膜缘移植治疗眼表碱烧伤的疗效明显优于单纯异体角膜移植 ,是一种较有效的方法。  相似文献   
38.
目的:检测眼表碱烧伤角膜缘移植术后血管抑素抑制角膜新生血管的作用。方法:16只新西兰大白兔双眼制作碱烧伤模型1d后,双眼行角膜缘移植术,术后左眼局部应用血管抑素治疗2周,右眼作对照;观测4周,根据新生血管侵入角膜缘内的范围、角膜混浊与水肿程度进行分级并作统计学处理;同时测量术后7、14、21及28d的眼压。结果:术后4周时,应用血管抑素的左眼的新生血管的评分为1.19±0.10,而对照组为1.63±0.72,统计学处理显示左眼的新生血管较右眼的明显减少(P<0.05),角膜混浊与水肿程度亦明显下降。各时间点各术眼的眼压均在正常范围,无统计学差异。结论:局部应用血管抑素能有效抑制眼表碱烧伤角膜缘移植术后的新生血管增生。  相似文献   
39.
Mutations in the fibroblast growth factor receptor genes (FGFR) have been known to be associated with many craniosynostosis syndromes with overlapping phenotypes. We studied a 15‐year‐old Thai boy with an unspecified craniosynostosis syndrome characterized by multiple suture craniosynostoses, a persistent anterior fontanel, corneal scleralization, choanal stenosis, atresia of the auditory meatus, broad thumbs and great toes, severe scoliosis, acanthosis nigricans, hydrocephalus, and mental retardation. Radiography revealed bony ankyloses of vertebral bodies of T9–12, humero‐radio‐ulnar joints, intercarpal joints, distal interphalangeal joints of fifth fingers, fibulo‐tibial joints, intertarsal joints, and distal interphalangeal joints of the first toes. The patient was a heterozygous for a 870G → T change resulting in a W290C amino acid substitution in the extracellular domain of the fibroblast growth factor receptor 2 gene (FGFR2). This mutation has previously been reported in a patient with severe Pfeiffer syndrome type 2 that is distinct from the craniosynostosis in our patient. These findings emphasize locus, allelic, and phenotypic heterogeneity of craniofacial‐skeletal‐dermatological syndrome due to FGFR2 mutations. © 2002 Wiley‐Liss, Inc.  相似文献   
40.
A moderately severe thermal injury of the central cornea of 48 Dutch-belted rabbit eyes was produced with a carbon (CO2) laser. The lesions were photographed with a slit lamp (SL) camera immediately following the injury and at 1, 2, 4, 7, 14, 21, 30 and 60 days after the exposure. Lesion size, opaqueness, and depth were graded clinically by SL biomicroscopy at the same intervals. No significant differences were found (p 0.05) between groups of eyes treated with flurbiprofen (0.03%), prednisolone acetate (1%), and vehicle control four-times-a-day for three weeks following injury. Additionally, eyes were studied histopathologically at 3 and 60 days following injury by light and transmission electron microscopy, and clinically at 30 and 60 days by endothelial specular microscopy. Important clinical and histopathological findings included coagulative necrosis of the corneal epithelium, epithelial sloughing, fusion of stromal collagen, stromal edema and inflammatory cell infiltration, stromal scar formation, corneal thinning, endothelial hyperplasia and metaplasia, fibrinous anterior chamber reaction with hypopyon, and retrocorneal fibrous membrane formation.  相似文献   
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