首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   92054篇
  免费   8027篇
  国内免费   6219篇
耳鼻咽喉   764篇
儿科学   1024篇
妇产科学   942篇
基础医学   8669篇
口腔科学   1638篇
临床医学   13056篇
内科学   11413篇
皮肤病学   1000篇
神经病学   3545篇
特种医学   2888篇
外国民族医学   40篇
外科学   7693篇
综合类   19572篇
现状与发展   25篇
一般理论   3篇
预防医学   7805篇
眼科学   2302篇
药学   10692篇
  110篇
中国医学   6499篇
肿瘤学   6620篇
  2024年   302篇
  2023年   1112篇
  2022年   3002篇
  2021年   3704篇
  2020年   3030篇
  2019年   2527篇
  2018年   2415篇
  2017年   2780篇
  2016年   2331篇
  2015年   3947篇
  2014年   4930篇
  2013年   4829篇
  2012年   7451篇
  2011年   7988篇
  2010年   6105篇
  2009年   5408篇
  2008年   6007篇
  2007年   5981篇
  2006年   5771篇
  2005年   5398篇
  2004年   3633篇
  2003年   3197篇
  2002年   2699篇
  2001年   2111篇
  2000年   1788篇
  1999年   1585篇
  1998年   1041篇
  1997年   1002篇
  1996年   730篇
  1995年   654篇
  1994年   599篇
  1993年   373篇
  1992年   359篇
  1991年   313篇
  1990年   278篇
  1989年   197篇
  1988年   194篇
  1987年   158篇
  1986年   135篇
  1985年   89篇
  1984年   35篇
  1983年   29篇
  1982年   18篇
  1981年   23篇
  1980年   12篇
  1979年   11篇
  1974年   5篇
  1972年   3篇
  1970年   3篇
  1936年   2篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
目的 探讨自制苏芪合剂对Ⅲ~Ⅳ级IgA肾病患者的疗效及患者T细胞功能的改善.方法 28例Ⅲ~Ⅳ级IgA肾病患者随机分为两组,对照组:醋酸泼尼松-日1mg,kg,隔日晨起顿服,盐酸苯那普利-日10mg;治疗组:在上述用药的基础上加用自制苏芪合剂.8周后,观察患者缓解率、T细胞功能及不良反应.结果 治疗组患者在缓解率、T细胞功能改善等方面优于对照组,且因糖皮质激素的使用而出现的不良反应少于对照组.结论 苏芪合剂联合治疗Ⅲ~Ⅳ级IgA肾病疗效显著并能有效改善T细胞功能.  相似文献   
62.
According to traditional teaching mode, the courses in preclinical medicine including pharmacology are separately run. This mode causes a series of disadvantages including loose connection between knowledge in different disciplines and weak ability to bridge basic preclinical knowledge and clinical practice. In order to overcome the disadvantages and promote the teaching efficiency, we constructed a new integrated course-Course of Basic Medical Sciences, which includes 6 traditional courses, anatomy, histology and embryology, physiology, pathology, pathophysiology and pharmacology. We integrated these courses based on the human organ systems and according to the principle-" From macro to micro, From morphological to functional, From normal to abnormal and From disease to drug therapy" and published the series of textbook in 2004. The contents of pharmacology are taught just after pathology and pathophysiology in every organ system. In comparison with the traditional teaching mode, teachers of pharmacology need not spend a lot of time to review preceding knowledge of anatomy and histology, physiology, pathophysiology and pathology. This is helpful in saving time and improving the teaching efficiency.  相似文献   
63.
目前治疗腰椎间盘突出症主要用椎间的旋转复位法,包括定点旋转复位和侧卧斜扳复位。自2004年8月以来,笔者在临床中遇到部分患者不配合或不能完成旋转复位法,因而采用自创凿击复位法,取得满意效果,现报告如下。  相似文献   
64.
BACKGROUND: Thrombolysis therapy is not suitable for the elderly patients with acute ischemic stroke who delayed to be diagnosed for more than 3 hours, but traditional medicine is also not very ideal.OBJECTIVE: To observe the clinical therapeutic effect of modified hemodilution combined therapy applied in elderly patients with acute cerebral thrombosis and analyze the mechanism of this therapeutic method.DESIGN: 1:1 paired grouping according to gender and controlled observation.SETTING: Department of Internal Medicine, Chengzhanyuan District, First Hospital Affiliated to Zhejiang University.PARTICIPANTS Totally 90 elderly patients with acute ischemic stroke who received the treatment in the Cadre Ward and Mental Ward, Department of Internal Medicine, Chengzhanyuan District, First Hospital Affiliated to Zhejiang University from March 1996 to June 2004 were recruited. They all met the diagnosis criteria revised by the Fourth Academic Conference of National Cerebrovascular Diseases in 1995 and were diagnosed as acute ischemic stroke by skull CT. They were informed of therapeutic plan and detected items.According to 1:1 paired principle in gender, 90 enrolled patients were assigned into treated group (n=45)and control group (n=45). There were 39 male and 6 female in the treatment group, and they were aged (76±6)years, ranging from 71 to 84 years, and hospitalized at the 14th to 76th hours after onset. There were 39 male and 6 female in the control group, and they were aged (76±6)years , ranging from 70 to 82years, and hospitalized at the 16th to 72th hours after onset.METHODS: Therapeutic method: Patients of treated group received modified hemodilution combined therapy.200 mL whole blood of patients was exchanged with 500 mL dextran-40 (including 20 mL danshen parenteral solution and 32 mg heparin) at the beginning of therapy; From the 2nd day, compound huangqi tea bag (Huangqi mainly, including danshen, honghua, chuanxiong, shishao and a little acetyl salicylic acid) was made, twice a day, 1 bag once. At the same time, the above-mentioned dextran-40 liquid of 500 mL was intravenously injected, once a day, 14 days in total; On the 6th day after therapy, the above-mentioned aseptic autoblood stored in refrigerator at 4 ℃ was transfused back into the patients following pre-treatment of high-concentration oxygenation and ultraviolet irradiation by light quantum instrument. Patients of control group were intravenously injected of 0.4 g venoruton(Traditional Chinese medicine compound parenteral solution for promoting blood circulation and removing blood stasis ) and 50 g/L glucose of 500 mL, 75 mg coagulation index, change of platelet aggregation rate and change of hemorrheology of patients in two groups were monitored before and after therapy. The level of blood lipid of patients in two groups was measured with American Beckman automatic biochemistry analyzer. Blood flow rate of middle cerebral artery of resting electrocardiogram were measured with American HP SONOS 2500 sonoscope. Neuro-dysfunction score revised in the national conference (1995) was used to evaluate the recovery of neurological function effect were observed at the same time.effect of drug.RESULTS: Totally 90 patients were enrolled in the experiment. One patient from treated group died of hyperosmolar nonketotic diabetic coma of complicated diabetes mellitus. One patient from control group died ulation index and platelet aggregation rate: prothrombin time (PT), activated partial thromboplastin time (APTT) and thrombin time (TT) of patients after therapy were significantly longer than those before therapy in the treated group and those after therapy in control group [After therapy in treated group: (18.4±1.9),(41.8±2.1), (19.7±1.7)s, Before therapy in treated group: (13.4±1.3), (35.8±1.3), (12.5±0.9)s, After therapy in control group: (16.9±1.5), (39.1±1.1), (11.9±2.1) s, P < 0.05] ;Concentration of fibrinogen (Fbg) after therapy was significantly lower than that before therapy in the treated group and that after therapy in control group[After therapy in treated group: (3.4±0.4) g/L; Before therapy in treated group: (4.3±0.7) g/L;After therapy in control group:(4.0±0.6) g/L; P < 0.05]. Platelet aggregation rate decreased from (37.92of total cholesterol (TC), triacylglycerol(TG) and Iow density lipoprotein cholesterol (LDL-C) of patients after therapy were significantly lower than those before therapy in treated group and those after therapy in control group [After therapy in treated group: (5.2±0.9), (1.9±0.9), (2.08±1.1) mmol/L, before therapy in treated group:(5.9±1.2), (2.8±0.9), (3.94±0.5) mmol/L, After therapy in control group: (6.0±1.1), (2.6±0.8), (3.84±0.9) mmol/L,after therapy than before therapy [Before therapy: (43.84±4.55)% ;After therapy: (40.48±4.02)% ;P < 0.05].cantly lower than of control group 14 days after therapy. The total effective rate after therapy was signifiadverse effect.CONCLUSION: Modified hemodilution combined therapy can improve hemorheology, decrease hematocrit,increase blood flow rate of middle cerebral artery, so as to improve the impaired clinical neurological function of elderly patients with acute cerebral thrombosis through anticoagulation and antiplatelet aggregative activity as well as regulating blood lipid.BACKGROUND: Thrombolysis therapy is not suitable for the elderly patients with acute ischemic stroke who delayed to be diagnosed for more than 3 hours, but traditional medicine is also not very ideal.OBJECTIVE: To observe the clinical therapeutic effect of modified hemodilution combined therapy applied in elderly patients with acute cerebral thrombosis and analyze the mechanism of this therapeutic method.DESIGN: 1:1 paired grouping according to gender and controlled observation.SETTING: Department of Internal Medicine, Chengzhanyuan District, First Hospital Affiliated to Zhejiang University.PARTICIPANTS:Totally 90 elderly patients with acute ischemic stroke who received the treatment in the Cadre Ward and Mental Ward, Department of Internal Medicine, Chengzhanyuan District, First Hospital Affiliated to Zhejiang University from March 1996 to June 2004 were recruited. They all met the diagnosis criteria revised by the Fourth Academic Conference of National Cerebrovascular Diseases in 1995 and were diagnosed as acute ischemic stroke by skull CT. They were informed of therapeutic plan and detected items.According to 1:1 paired principle in gender, 90 enrolled patients were assigned into treated group (n=45)and control group (n=45). There were 39 male and 6 female in the treatment group, and they were aged (76±6)years, ranging from 71 to 84 years, and hospitalized at the 14th to 76th hours after onset. There were 39 male and 6 female in the control group, and they were aged (76±6)years , ranging from 70 to 82years, and hospitalized at the 16th to 72th hours after onset.METHODS: Therapeutic method: Patients of treated group received modified hemodilution combined therapy.200 mL whole blood of patients was exchanged with 500 mL dextran-40 (including 20 mL danshen parenteral solution and 32 mg heparin) at the beginning of therapy; From the 2nd day, compound huangqi tea bag (Huangqi mainly, including danshen, honghua, chuanxiong, shishao and a little acetyl salicylic acid) was made, twice a day, 1 bag once. At the same time, the above-mentioned dextran-40 liquid of 500 mL was intravenously injected, once a day, 14 days in total; On the 6th day after therapy, the above-mentioned aseptic autoblood stored in refrigerator at 4 ℃ was transfused back into the patients following pre-treatment of high-concentration oxygenation and ultraviolet irradiation by light quantum instrument. Patients of control group were intravenously injected of 0.4 g venoruton(Traditional Chinese medicine compound parenteral solution for promoting blood circulation and removing blood stasis ) and 50 g/L glucose of 500 mL, 75 mg acetosal was taken orally, once a day, 14 days in total. ② Measurement and observation of index: Blood coagulation index, change of platelet aggregation rate and change of hemorrheology of patients in two groups were monitored before and after therapy. The level of blood lipid of patients in two groups was measured with American Beckman automatic biochemistry analyzer. Blood flow rate of middle cerebral artery of resting electrocardiogram were measured with American HP SONOS 2500 sonoscope. Neuro-dysfunction score revised in the national conference (1995) was used to evaluate the recovery of neurological function of the patients in two groups at the 3rd, 5th, 7th and 14th days after therapy. ③Therapeutic effect and adverse effect were observed at the same time.MAIN OUTCOME MEASURES: ① Changes of coagulation index, blood lipid level and hemorheology; ② Blood flow rate of middle cerebral artery and NDS of patients with acute ischemic stroke in two groups; ③Adverse effect of drug.RESULTS: Totally 90 patients were enrolled in the experiment. One patient from treated group died of hyperosmolar nonketotic diabetic coma of complicated diabetes mellitus. One patient from control group died of severe pulmonary infection. The rest 88 patients entered the stage of result analysis. ① Change of coagulation index and platelet aggregation rate: prothrombin time (PT), activated partial thromboplastin time (APTT) and thrombin time (TT) of patients after therapy were significantly longer than those before therapy in the treated group and those after therapy in control group [After therapy in treated group: (18.4±1.9),(41.8±2.1), (19.7±1.7)s, Before therapy in treated group: (13.4±1.3), (35.8±1.3), (12.5±0.9)s, After therapy in control group: (16.9±1.5), (39.1±1.1), (11.9±2.1) s, P < 0.05] ;Concentration of fibrinogen (Fbg) after therapy was significantly lower than that before therapy in the treated group and that after therapy in control group[After therapy in treated group: (3.4±0.4) g/L; Before therapy in treated group: (4.3±0.7) g/L;After therapy in control group:(4.0±0.6) g/L; P < 0.05]. Platelet aggregation rate decreased from (37.92±0.85)% before therapy to (26.42±1.01)% after therapy (P < 0.01). ②Change of blood lipid level: Levels of total cholesterol (TC), triacylglycerol(TG) and Iow density lipoprotein cholesterol (LDL-C) of patients after therapy were significantly lower than those before therapy in treated group and those after therapy in control group [After therapy in treated group: (5.2±0.9), (1.9±0.9), (2.08±1.1) mmol/L, before therapy in treated group:(5.9±1.2), (2.8±0.9), (3.94±0.5) mmol/L, After therapy in control group: (6.0±1.1), (2.6±0.8), (3.84±0.9) mmol/L,P < 0.05]. ③ Change of hemorheology index: Hematocrit of patients of treated group was significantly lower after therapy than before therapy [Before therapy: (43.84±4.55)% ;After therapy: (40.48±4.02)% ;P < 0.05].④ Blood flow rate of middle cerebral artery of patients of treated group was significantly lower before therapy than after therapy [(90±1.2), (97±2.1) cm/s,P < 0.01]. ⑤ NDS of patients in treated group was significantly lower than of control group 14 days after therapy. The total effective rate after therapy was significantly higher in the treated group than in the control group (93%,78%, P < 0.05). ⑥There was no obvious adverse effect.CONCLUSION: Modified hemodilution combined therapy can improve hemorheology, decrease hematocrit,increase blood flow rate of middle cerebral artery, so as to improve the impaired clinical neurological function of elderly patients with acute cerebral thrombosis through anticoagulation and antiplatelet aggregative activity as well as regulating blood lipid.  相似文献   
65.
Objective To investigate the role of p38a pathway and HO-1 in the genesis and chemotherapy resistance of breast cancer. Methods The proliferation and apoptosis of human breast cancer cells were examined by MTT assay. The expression of p38a and HO-1 mRNA were examined by RT-PCR. Results The p38a mRNA level in 78 % of samples was significantly greater than that in the normal tissue and the p38a mRNA level in patients with lymph node metastasis was higher than that without lymph node metastasis (P 〈 0.01 ). The HO-1 activated with 5 μmol/L pirarubicin increased more in MCF-7/adr cells than in MCF-7 cells, and was completely blocked by p38a inhibitor in MCF-7/ADR but only partially in the MCF-7 cell line.  相似文献   
66.
The role of MHC class Ⅱ transactivator (CⅡTA) in constitutive or IFN-γ inducib|e expression of HLA molecules in human malignant hematological cell lines was investigated. The expression of HLA molecules and CⅡTA protein was detected by Western blot, immunohistochemistry and flow cytometry. The expression of CⅡTA gene was determined by RT-PCR. The capability of peripheral blood T cell reaction stimulated by tumor cells was monitored by mixed lymphocyte reaction. It was found that the HLA Ⅱ-positive tumor cells expressed the CⅡTA quite well, andthe expression of HLA Ⅰ+Ⅱ was increased in the tumor cells with constitutive or inducible expression of CⅡTA after induced by IFN-γ. The tumor cells which did not express CⅡTA after in-duced by IFN-γ were not response to the expression of HLA Ⅱ promoted by IFN-γ. It suggests a correlation between the inability of some malignant hematological cell lines in response to IFN-γ for HLA expression and the deficiency in the inducible expression of CⅡTA, indicating CⅡTA might take part in the regu|ation of HLA Ⅰ+Ⅱ expression in the tumor cells, which might p|ay an important role in tumor immunologic escape.  相似文献   
67.
目的研究MAGE-A3抗原肽负载对乳腺癌患者树突状细胞(DC)的功能的影响,探讨其是否可以在体外诱导特异性细胞毒性T淋巴细胞(CTL)应答.方法体外培养HLA-A2乳腺癌患者外周血来源的DC,并经孵育携带MAGE-A3抗原肽,用以刺激CTL,用3H-TdR渗入法检测抗原肽负载前后DC刺激同种淋巴细胞增殖能力(MLR),并用乳酸脱氢酶(LDH)释放法检测CTL对靶细胞的杀伤效应.结果DC:T为1:10时,单纯DC组刺激能力显著高于抗原肽负载组DC(DC-P)(P<0.05),但当DC:T低于1:20时后DC-P组刺激能力显著强于单纯DC组(P<0.05).DC-P组和单纯DC组所激发的CTL对细胞株MCF-7,Sk-Br-3,MDA-MB-435s的杀伤活性有显著性差异,而对细胞株Raji无显著性差异,DC-P组对细胞株MCF-7,Sk-Br-3,MDA-MB-435s的杀伤活性明显高于对细胞株Raji的杀伤活性.结论负载MAGE-A3抗原肽的DC在体外可以诱导乳腺癌患者特异性的CTL免疫应答,为临床以DC为基础的过继免疫治疗的应用提供理论基础.  相似文献   
68.
血管内皮生长因子与妊娠高血压综合征发病的关系   总被引:2,自引:0,他引:2  
谢兰  罗军  陈廉  邹冰玉  杨年 《四川医学》2003,24(8):773-775
目的 探讨血管内皮生长因子 (VEGF)在妊娠高血压综合征发病中的作用。方法 分别采用酶联免疫吸附试验检测 40例妊高征孕妇的血清VEGF水平 ,免疫组化检测胎盘及蜕膜组织VEGF及CD3 4表达情况 ,35例正常孕妇作对照。结果 ①妊高征组孕妇的外周血VEGF水平及胎盘组织MVD明显低于正常妊娠组 (P <0 0 5 ) ;②两组胎盘绒毛滋养叶细胞和蜕膜组织中均有VEGF阳性表达 ,胎盘组织强阳性表达高于蜕膜。与对照组比较 ,其胎盘组织VEGF强阳性表达的轻度妊高征无显著性差异 ;而中度和重度妊高征与对照组相比 ,则明显降低 ,差异显著 (P <0 0 5 )。各组孕妇蜕膜组织中VEGF的表达强度和差异无显著性。③孕妇外周血VEGF水平与新生儿出生体重 (r =0 2 9,P <0 0 5 )和胎盘重量 (r =0 34,P <0 0 1)均存在直线正相关关系。结论 妊高征患者血清VEGF水平和胎盘组织MVD降低 ,胎盘组织VEGF表达明显下降 ,都可能在妊高征的发病中起一定的作用。  相似文献   
69.
目的 判定增龄对皮肤血流量的影响。方法 用PIM2-LDPI检测皮肤血流量。结果 老年组前额、左手指背、命门穴部位皮肤血流量分别为:(1.94±0.86)V,(1.92±0.52)V和(0.71±0.19)V,与青年组比较差异无显著性。但是,老年男性在命门穴的皮肤血流量明显高于青年男性(P<0.05),老年女性前额的皮肤血流量明显降低(P<0.01)。男性比女性的皮肤血流量高。结论 皮肤血流量的差异无年龄相关性,男性组的皮肤血流量比女性组高。  相似文献   
70.
螺旋CT多功能重建在骨关节外伤中的应用   总被引:2,自引:0,他引:2  
目的 探讨螺旋cT功能重建在骨与关节外伤中的应用,提高重建技术的使用能力和诊断水平。方法 对使用双层螺旋CT,SSD,MPR,MIP等多种方式重建检查的49例复杂的骨与关节外伤病例进行回顾性分析。结果 49例骨关节外伤重建成像,其中,颅底3例,颌面部7例,颈、胸、腰、骶椎共17例,肩胛骨3例,髋关节8例,膝关节11例。SSD在显示碎骨片明显移位的空间关系方面较MIP,MPR为佳,它可以直观地、立体地、清晰地、多角度显示骨关节损伤,而MIP在显示骨折细节方面较优,尤其在外伤中颅窝观察有关神经孔方面。结论 螺旋CT的SSD,MPR和MIP技术的综合应用,对复杂的骨折、关节损伤的显示效果良好,具有较高的临床应用价值。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号