全文获取类型
收费全文 | 31860篇 |
免费 | 2892篇 |
国内免费 | 2416篇 |
专业分类
耳鼻咽喉 | 234篇 |
儿科学 | 259篇 |
妇产科学 | 331篇 |
基础医学 | 3745篇 |
口腔科学 | 490篇 |
临床医学 | 4706篇 |
内科学 | 4647篇 |
皮肤病学 | 249篇 |
神经病学 | 1712篇 |
特种医学 | 1062篇 |
外国民族医学 | 21篇 |
外科学 | 2903篇 |
综合类 | 5404篇 |
现状与发展 | 5篇 |
一般理论 | 2篇 |
预防医学 | 1820篇 |
眼科学 | 1192篇 |
药学 | 3603篇 |
26篇 | |
中国医学 | 1886篇 |
肿瘤学 | 2871篇 |
出版年
2024年 | 114篇 |
2023年 | 565篇 |
2022年 | 1475篇 |
2021年 | 1758篇 |
2020年 | 1353篇 |
2019年 | 1210篇 |
2018年 | 1115篇 |
2017年 | 1155篇 |
2016年 | 996篇 |
2015年 | 1584篇 |
2014年 | 1848篇 |
2013年 | 1521篇 |
2012年 | 2316篇 |
2011年 | 2533篇 |
2010年 | 1510篇 |
2009年 | 1178篇 |
2008年 | 1575篇 |
2007年 | 1574篇 |
2006年 | 1610篇 |
2005年 | 1818篇 |
2004年 | 993篇 |
2003年 | 854篇 |
2002年 | 779篇 |
2001年 | 676篇 |
2000年 | 651篇 |
1999年 | 762篇 |
1998年 | 537篇 |
1997年 | 503篇 |
1996年 | 397篇 |
1995年 | 369篇 |
1994年 | 308篇 |
1993年 | 219篇 |
1992年 | 236篇 |
1991年 | 213篇 |
1990年 | 193篇 |
1989年 | 147篇 |
1988年 | 149篇 |
1987年 | 106篇 |
1986年 | 101篇 |
1985年 | 66篇 |
1984年 | 29篇 |
1983年 | 24篇 |
1982年 | 11篇 |
1981年 | 19篇 |
1980年 | 9篇 |
1979年 | 8篇 |
1977年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
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
52.
叶颖江 《中国医学文摘:外科学分册英文版》2006,15(2):98-99
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
53.
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
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
54.
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
55.
Z-Y Sun J Wei L Xie Y Shen S-Z Liu G-Z Ju J-P Shi Y-Q Yu X Zhang Q Xu G P Hemmings 《European psychiatry》2004,19(6):354-357
The present study was designed to detect three single nucleotide polymorphisms (SNPs) located on 22q11 that was thought as being of particularly importance for genetic research into schizophrenia. We recruited a total of 176 Chinese family trios of Han descent, consisting of mothers, fathers and affected offspring with schizophrenia for the genetic analysis. The transmission disequilibrium test (TDT) showed that of three SNPs, rs10314 in the 3'-untranslated region of the CLDN5 locus was associated with schizophrenia (chi(2) = 4.75, P = 0.029). The other two SNPs, rs1548359 present in the CDC45L locus centromeric of rs10314 and rs739371 in the 5'-flanking region of the CLDN5 locus, did not show such an association. The global chi-square (chi(2)) test showed that the 3-SNP haplotype system was not associated with schizophrenia although the 1-df test for individual haplotypes showed that the rs1548359(C)-rs10314(G)-rs739371(C) haplotype was excessively non-transmitted (chi(2) = 5.32, P = 0.02). Because the claudin proteins are a major component for barrier-forming tight junctions that could play a crucial role in response to changing natural, physiological and pathological conditions, the CLDN5 association with schizophrenia may be an important clue leading to look into a meeting point of genetic and environmental factors. 相似文献
56.
口腔局部使用干扰素对小鼠唾液SIgA的调节 总被引:1,自引:0,他引:1
目的 :了解干扰素对口腔粘膜分泌SIgA的调节作用。方法 :以生物素 -ELISA法检测口腔使用干扰素前后小鼠唾液SIgA的水平。结果 :大、小剂量干扰素组在用药后 10天、2 0天和 3 0天都能增高唾液SIgA ,并同对照组相比有显著差异 (P <0 0 5 ) ;大剂量组SIgA的增高更多 ,特别是在 2 0天时明显高于小剂量组 (P <0 0 5 ) ;干扰素的调节作用持续至少 3 0天 ,小剂量在维持作用方面不亚于大剂量。结论 :干扰素直接作用于口腔粘膜 ,可提高局部的SIgA的分泌水平。 相似文献
57.
58.
59.
股骨头缺血坏死的低场MRI评价 总被引:9,自引:1,他引:8
目的: 分析股骨头缺血坏死(ANFH)低场MRI征象,评价ANFH的MRI分期及其关节积液的分级.材料和方法:在分析50例正常髋MRI基础上回顾性对照分析51例(90个股骨头)ANFH的低场MRI和X线平片资料.结果:90个ANFH中,20个(22 %) X线平片为阴性;64个(71%)MRI示"脂肪强度征"即坏死区内或近侧可见类似皮下脂肪样信号.按照 Hungerford分期:0期9个,Ⅰ期13个,Ⅱ期31个,Ⅲ期26个,Ⅳ期11个.ANFH引起的关节积液多为2~3级(60个髋,占67%);Ⅲ、Ⅳ期ANFH合并关节积液量比0~Ⅱ期明显多(P<0.005).结论:低场MRI能够准确显示ANFH的范围、程度、信号特征及其关节积液的情况,并能够对早期ANFH作出可靠诊断;"脂肪强度征"为低场MRI的特征性表现,对诊断ANFH有非常重要的价值. 相似文献
60.
Jiyou Li Yuquan Xie Guizhi Shi Heling Sun Xinhua Ji Maolin Jin Boqin Yang Mingsheng Wang 《中国癌症研究》1992,4(2):10-12
In order to investigate the antagonistic effect of Glycyrrhiza Uralensis Fish (GUF) and Chelidonium maJus L (CML) on gastrccarcinogenesis
induced by MNNG in Wastar rats, we treated the rats with MNNG alone (group 1) and with MNNG plus GUF and CML (group 2 and
3) respectively. The incidence of infiltrating adenocarcinoma of the glandular stomach and duodenum in group 2 was significantly
lower than that in group 1 (26.7% vs. 67.8%). The differentiation and aggressivenees of carcinomas occured in group 2 were
much better and mild than those in group 1. Present study also demonstrated that the inhibitory effect of CML on proliferation
of human stomach carcinoma cell line MGC-803 was very remarkable; in addition, GUF and CML were able to antagonise the mutagenic
activation of MNNG. These results suggest that GUF and CML may be empoyed in prevention of gastric carcinoma. 相似文献