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91.
BACKGROUND: Although it has been reported that ghost cells are present in odontomas, the generation mechanism of these cells is unclear. To evaluate the presence of ghost cells and involvement of the Wnt signaling pathway, we examined the expression of hard keratins, beta-catenin and Lef-1 in odontomas. METHODS: Sixty-nine cases of odontoma were examined immunohistochemically with the use of antibodies against human hair proteins, beta-catenin and Lef-1. RESULTS: Expression of hard keratins was found only in the cytoplasm of ghost cells in 46 (66.7%) of the 69 odontomas. Compound odontomas (78.8%) showed a higher incidence of ghost cells than complex odontomas (29.4%). Histopathologically, ghost cells were found within odontogenic epithelium adjacent to immature enamel and in the centre of Liesegang-ring-like calcified materials. Expression of beta-catenin and Lef-1 was observed in the cytoplasm and nucleus of odontogenic epithelial cells adjacent to the ghost cells in immature odontomas. CONCLUSION: These findings suggest that odontoma is a hard keratin-expressing tumor-like lesion, and that the Wnt signaling pathway may be involved in the formation of ghost cells in odontomas.  相似文献   
92.
中药白芷硫熏前后香豆素成分含量比较   总被引:16,自引:6,他引:10  
用薄层扫描法对川白芷和杭白芷药材加工(硫熏)前后的香豆素类成分进行了含量测定。香豆素含量分别为0.190%、0.571%、0.178%、0.421%。  相似文献   
93.
目的:构建含有目的基因kring5的真核植物细胞穿酸表达载体。方法:应用RT-PCR方法,从正常人肝脏组织中获得kringle5基因,测序后,再通过DNA重组技术,将kringle5基因片段克隆到真核植物细胞表达载体pBI121和pCAMBIA3301上。结果:得到的kringle5基因序列测定结果与文献相符,重组载体pB1k5和pC33k5经酶切鉴定正确,含有植物高效表达CaMV35S启动子。结论:重组载体pB1k5和pC33k5不仅可以在大肠杆菌中稳定复制,而且可以在植物细胞中表达。  相似文献   
94.
头孢氨苄缓释片在健康人体内的生物利用度和药物动力学   总被引:2,自引:0,他引:2  
目的:比较头孢氨苄缓释片和普通胶囊的生物利用度和药物动力学。方法:10例健康志愿者分别单剂量口服500mg头孢氨苄缓释片和普通胶囊,血药浓度测定方法为HPLC法。结果:两种剂型体内过程均符合一室开放模型,缓释片的达峰时间(Tmax)为(2.58±0.59)h,峰浓度(Cmax)为(10.08±1.68)μg/ml.吸收速率常数(Ka)为(0.90±0.53)/h,消除速率常数(Ke)为(0.26±0.02)/g,半衰期(T1/2)为(2.67±0.23)h,清除率(Cl)为(6.93±1.71)L/h,分布容积(Vd)为(26.66±6.72)L,药一时曲线下面积(AUC)为(48.31±9.32)μg·h/ml。两种剂型T一C一Ka、Ke、T1/2和Cl均存在显著性差异(P<0.01),Vd、AUC无显著性差异(P>0.05);缓释片的相对生物利用度为(104.90±8.35)%。结论:缓释片的吸收减慢,Tmax推迟,T1/2延长,可减少服药次数,提高药物治疗的顺应性。  相似文献   
95.
96.
周围神经损伤后勃起功能障碍的治疗进展   总被引:3,自引:0,他引:3  
外伤、手术可因盆神经丛和 (或 )海绵体神经损伤而造成勃起功能障碍。较理想的治疗方法是使损伤神经自我再生修复 ,完全恢复勃起功能。本文综述近年来勃起神经损伤后再生修复方面的研究进展 ,试图寻找出一种促进损伤的勃起神经再生的最佳方法  相似文献   
97.
莫沙必利联合铝碳酸镁治疗胆汁反流性胃炎疗效观察   总被引:2,自引:0,他引:2  
成祝森  吴震 《右江医学》2004,32(6):525-526
目的 探讨铝碳酸镁及莫沙必利对胆汁反流性胃炎的疗效。方法 将 45例经胃镜证实胃液内有胆汁贮留及胃窦明显炎症的胆汁反流性胃炎随机分为A、B、C组。A组 ( 15例 )服用莫沙必利 5mg/次 ,3次 /d ;B组 ( 16例 )服用铝碳酸镁 1.0g/次 ,3次/d ;C组 ( 14例 )同时服用西沙必利和铝碳酸镁 ,剂量同A、B组。治疗 4周后观察上腹痛、腹胀、恶心、呕吐症状变化。结果 治疗后三组患者症状均明显减轻 ( P <0 .0 5或 <0 .0 1) ,C组症状改善更明显 ( P <0 .0 5或 <0 .0 1)。结论 莫沙必利、铝碳酸镁联合应用治疗肝胆汁反流性胃炎的疗效优于单一用药  相似文献   
98.
目的 对供者肝脏等器官的联合获取、修整和保存方法进行研究。方法 采用原位腹主动脉和门静脉插管、低温灌注,快速多器官联合获取、低温保存技术及体外修整获得可供移植的肝移植物。结果 获取122例供者的移植物,平均热缺血时间为4min30s,平均获取时间为20min,平均冷缺血时间为10h。均采用4℃的HCA液(高渗枸橼酸盐腺嘌呤溶液)和UW液灌注和保存。118例修整成适用于临床用的肝的移植物,76例供肝在移植前留取了病理活检标本,病理检查提示供肝结构正常。移植术后,无原发性肝无功能发生。结论 该方法适合于供者肝脏等器官的快速联合获取、修整和保存。  相似文献   
99.
慢性前列腺炎相关危险因素的调查报告   总被引:8,自引:1,他引:7  
目的:探索不良生活习惯、精神、心理等相关因素与慢性前列腺炎发病的关系. 方法:对600例慢性前列腺炎患者进行流行病学调查,采用单因素及多因素条件Logistic回归法进行统计分析,判断危险因素.结果:多因素Logistic回归分析发现引起慢性前列腺炎的可能因素为尿道炎、无节制的性生活、频繁的手淫、固定体位(尤其长时间骑跨、坐位)、酗酒、生活方式改变、长时间憋尿、紧张焦虑心理等.结论:本研究结果对慢性前列腺炎的预防、治疗及防止复发具有参考价值.  相似文献   
100.
BACKGROUND: Human insulin-like growth factor (hIGF-1) has been successful in treating peripheral nerve injury, but it is still unclear whether hIGF-1 after transgene in vivo has the effect on promoting the regeneration of peripheral nerve. OBJECTIVE: To observe the effect of hIGF-1 on the regeneration of peripheral nerve by transgene in vivo with electrophysiology, histological morphology and ultromicro morphology. DESIGN: A univariate design. SETTINGS: Jilin Institute of Surgery, China-Japan Friendship Hospital Affiliated to Jilin University; School of Basic Medical Sciences, Jilin University. MATERIALS: Thirty male adult Wistar rats of grade Ⅱ, weighing 200-250 g, were provided by the Animal Experimental Center of Jilin University [certification number: SCXK-(Ji)20030001]. The rats were raised in the environment at the temperature of 25 ℃ and humidity of 70%. All the rats were randomly divided into hIGF-1-treated group, treatment control group and blank control group, 10 rats in each group. Positive liposomes (mass concentration of 2 g/L) and pcDNA3.1 (mass concentration of 1 g/L) were purchased from Beijing Yuanpinghao Company; pcDNAhIGF-1 (mass concentration of 1 g/L) was provided by Dr. Shen from the School of Public Health of Jilin University. The liposomes were mixed with plasmids with the mass ratio of 1.5 to 10.Operative microscope was made by Jiangsu Zhenjiang Microsurgical Instrument Factory; EMB-5304K electromyogram (EMG) evoked potential meter by Nihon Kohden Corporation. HPIAS-1 000 high-acuity color pathological imaging analytical system (Japan) and JEM-1200EX transmission electron microscope (Japan) were also used. METHODS: The experiments were carried out in Jilin Institute of Surgery from April to June in 2004. ① All the rats were anesthetized, and the right sciatic nerve was exposed, and it was clipped with a clip at 5 mm below the piriform muscle for 3 times, 10 s for each time. The pressed width was 3 mm, and formed as membrane under operating microscope (×6). Rats in the hIGF-1-treated group were subepineurially injected with the mixture of pcDNAhIGF-1 and positive liposomes (10 μL) immediately, those in the treatment control group were injected with the mixture of pcDNA3.1, positive liposomes and distilled water (10 μL), and those in the blank control group were not given any injection. ② The sciatic nerve functional indexes (SFI) were measured within 56 days postoperatively according to the methods used by Shen et al. ISFI=0 was taken as normal, and ISFI=-100 as completely damaged. EMG evoked potential meter was used to record the electrophysiological changes of the regenerated nerve fibers. The indexes of histological morphology in 5 randomly selected sights were determined with the color pathological imaging analytical system, and the ultrostructures of the regenerated nerve fibers were also observed. MAIN OUTCOME MEASURES: ① Comparison of the SFI within 56 days postoperatively; ② Comparison of the electrophysiology, histological morphology and ultrastructure of the regenerated nerve fibers 56 days postoperatively. RESULTS: All the 30 Wistar rats were involved in the analysis of results. ① SFI: The SFI values were gradually increased as time prolonged in all the three groups, and the changes were more obvious after 24 days, the SFI values recovered better at each time point in the hIGF-1-treated group than in the other two groups. ② Eelectrophysiological results of right sciatic nerve: The latency of motor evoked potential (MEP) was close between the treatment control group and the blank control group [(2.55±0.36), (2.65±0.55) ms, P > 0.05], but higher in the hIGF-1-treated group [(2.14±0.22) ms] than in the blank control group (P < 0.01). The amplitude and conduction velocity of MEP in the treatment control group [(6.67±0.69) mV, (29.57±4.06) m/s] were close to those in the blank control group [(6.60±0.59) mV, (29.22±3.20) m/s, P > 0.05], but those in the hIGF-1-treated group [(7.81±0.84) mV, (36.91±4.37) m/s] were larger or faster than those in the blank control group (P < 0.01). ③ Results of the pathological image analysis of the regenerated nerve fibers: The axonal diameter, thickness of myelin sheath of the regenerated nerve fiber and the number of myelinated nerve fiber in the treatment control group [(2.28±0.33) μm, (1.08±0.18) μm2, (71.80±8.25) fibers] were close to those in the blank control group [(2.18±0.29) μm, (1.03±0.15) μm2, (68.60±8.55) fibers] (P > 0.05), and those in the hIGF-1-treated group [(3.03±0.35) μm, (1.65±0.24) μm2, (88.20±8.82) fibers] were obviously larger or more than those in the blank control group (P < 0.01). ④ Ultrastructure of the regenerated nerve fibers of sciatic nerve: In the hIGF-1-treated group, the regenerated fibers of sciatic nerve were more and mature, manifested by thicker nerve fibers, thicker and evener myelin sheath, which were better than those in the other two groups. CONCLUSION: The results of the quantitative parameters of the electrophysiology, gross histological morphology and ultrostructural changes in the process of repairing damaged peripheral nerve indicate that transgene in vivo with hIGF-1 can promote the neural regeneration after peripheral nerve injury.  相似文献   
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