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31.
目的 研究偏头痛患儿的脑动脉血流动力学改变 ,探讨其在小儿偏头痛发生中的作用。方法 应用经颅多普勒 (TCD)技术 ,检测 90例 7~ 14岁头痛间歇期的偏头痛患儿和 80例健康同龄儿童脑动脉血管血流动力学指标。结果  90例偏头痛患儿中脑动脉血流动力学异常者 77例 (86 % ) ,其中 6 0例 (6 7% )流速增快 ,9例 (10 % )减慢 ,与对照组相比 ,差异具有显著性 (P <0 0 1) ;90例中 2 3例 (2 6 % )存在双侧同名动脉血流速度不对称 ,其中伴有血流速度异常者15例 ,血流速度正常者 8例 ,差异具有显著性 (P <0 0 1)。结论 脑动脉血流动力学因素异常改变 ,在小儿偏头痛的发生中具有重要作用。尤其值得注意的是 ,双侧同名动脉流速不对称的改变 ,在小儿偏头痛的发生中同样可能起着重要的作用。  相似文献   
32.
目的:探讨缬沙坦和氯沙坦治疗轻中度原发性高血压的临床疗效及安全性。方法:117例轻中度原发性高血压患者随机分为两组,缬沙坦(治疗)组59例,80~160mg/d,口服,疗程半年;氯沙坦(对照)组58例,50~100mg/d,口服,疗程半年。治疗前后测偶测血压、动态血压、肝肾功能、血脂、血糖、血尿酸,血浆肾素活性(PRA)、血管紧张素Ⅱ(AngⅡ)醛固酮(ALd)、内皮素(ET)等,并观察心脑事件发生情况。结果:治疗组总有效率74.6%(44/59例),降压幅度26.2/15.1mmHg,谷/峰(T/P)比值:收缩压(SBP)0.28、舒张压(DBP)0.78,与对照组总有效率74.1%(43/58例),降压幅度25.9/15.8mmHg,T/P比值:SBP 0.81、DBP 0.79均相似(P均>0.05)。两组治疗后PRA、AngⅡ均升高(P均<0.05);Ald、ET均降低(P均<0.05),但组间对照无显著性差异(P>0.05)。血尿酸也明显下降(P均<0.05),且基础值越高,降幅越大,对于治疗前高尿酸血症患者,对照组降压大于治疗组(P<0.05)。半年随访,两组心脑血管事件发生率相似(P>0.05),治疗组不良么应轻微。结论:缬沙坦是一种安全、作用持久、稳定、耐受性好、用药方便的治疗轻中度原发性高血压的新型AngⅡⅠ型受(AT1)拮抗药物之一,值得临床推广应用。  相似文献   
33.

Chronic hepatitis B (CHB) has a wide range of outcomes depending on host immune responses mainly Toll-like receptors (TLRs) signaling and released cytokines. Toll-like receptor 2 (TLR2) single nucleotide polymorphisms (SNPs) and interleukin 6 (IL-6) may influence the course of CHB. We aimed to elucidate the relation between TLR-2 polymorphism, IL-6 profile, and CHB progression. We analyzed TLR-2 polymorphism (SNP; rs3804099) in 185 CHB patients and 60 controls using TaqMan allelic discrimination assay. Serum IL-6 levels were assessed by ELISA. IL-6 levels were considerably higher in active CHB and cirrhotic patients compared with inactive carriers and controls (P < 0.001). IL-6 showed positive correlation with ALT and advanced fibrosis in active CHB patients (r = 0.31, P = 0.02). A significant positive correlation was noticed between IL-6 and HBV DNA PCR in all CHB groups. TT genotype of rs3804099/TLR-2 was significantly more prevalent in inactive carriers compared to active hepatitis patients (P = 0.04, OR = 0.39 and 95% CI: 0.16–0.95). Both heterozygous CT and mutant TT genotypes were significantly more frequent among inactive carriers compared to cirrhotic patients (P = 0.01, OR = 0.33, 95% CI: 0.13–0.81 and P = 0.009, OR = 0.32, 95% CI: 0.13–0.77). TT genotype was significantly related to lower IL-6 levels in active hepatitis and cirrhotic groups (P = 0.005 and P = 0.001, respectively) showing that TLR mutations would be associated with milder hepatitis activity and lower possibility for disease progression. There may be a positive association between TLR2 rs3804099 polymorphism and hepatitis B activity. IL-6 is a good indicator of CHB disease progression.

  相似文献   
34.
目的:探讨L-精氨酸对病毒性心肌炎病理变化的影响。方法:将接种柯萨基病毒B3的Balb/c雄性小鼠随机分为饲服L-精氨酸组和对照组,于接种病毒后第5d测小鼠血清NO(NO2/NO3)和CK-MB,心肌组织病理学改变和超微结构变化。结果:血清NO(NO2/NO3)和血清CK-MB,L-精氨酸组高于对照组;心肌组织病理学检查可见L-精氨酸组小鼠心肌细胞有程度不等的空泡变性和坏死,病理损伤较对照组严重;  相似文献   
35.
目的:评价植入新型人工腰椎间盘的腰椎节段的稳定性和压缩力学性能。方法:将人工腰椎间盘植入6具新鲜青壮年尸体标本的L4-5椎间隙,进行三维运动范围和压缩刚度测试,并与植入前和髓核切除后进行比较。结果:新型人工腰椎间盘植入后,腰椎节段的三维运动范围为前屈146°,后伸66°,左侧弯79°,右侧弯89°,左轴向旋转85°,右轴向旋转87°。其压缩刚度比髓核切除后高(P<005)。结论:新型人工腰椎间盘植入后既保证了腰椎节段的三维运动功能,又起到了稳定脊柱的功能。  相似文献   
36.
 Cyclosporine is a powerful immunosuppressant with a narrow therapeutic window and considerable inter- and intrapatient variability. The pre-dose trough concentration (Cmin) is commonly used for therapeutic drug monitoring. With the new microemulsion (Neoral), intrapatient variability was reduced. However, the usefulness of Neoral Cmin was questioned. Firstly, because of the improved and more-rapid absorption, accidental intake before blood sampling has a greater impact on Cmin than with classic cyclosporine. Secondly, Cmin may be low despite high drug exposure, due to rapid clearance in children. A full pharmacokinetic (PK) profile with determination of the area under the curve (AUC) is expensive and cumbersome, and therefore a search for an abbreviated AUC began. Here, we present a retrospective analysis of 84 PK profiles from 78 pediatric renal transplant recipients. By analysis of rejection episodes and toxicity, we estimated a target AUC above 5,000 ng×h/ml in the early post-transplant period and 3,900 ng×h/ml beyond 100 days. The abbreviated AUC using the 2- and 6-h concentrations (C2 and C6) and a simple estimate derived from the 3-h concentration (C3) were equally well correlated with the AUC. From our data, we recommend a target C3 at approximately 800 ng/ml early after transplantation and 450–550 ng/ml beyond 100 days. Received: 28 January 1998 / Revised: 10 June 1998 / Accepted: 15 June 1998  相似文献   
37.
BACKGROUND/AIMS: Obstructive jaundice due to intraductal tumour growth is a rare symptom in association with hepatocellular carcinoma (HCC). METHODS: We report a 65-year-old white male who was admitted to our department with a 2-week history of progressive jaundice. At laparotomy, the liver showed advanced cirrhosis due to long-standing biliary obstruction. Cholangiography confirmed total obstruction of the main bifurcation of the hepatic duct by intraductal tumour growth. Combination treatment with surgical segment III drainage, transcatheter arterial embolization and radioembolization with yttrium-90 resin particles and endoscopic stenting was performed. This form of treatment has never been reported before. RESULTS: With these combined procedures, relief of jaundice and a survival time of 32 months could be achieved. CONCLUSION: The combination of palliative methods may relieve jaundice, ensure a good quality of life and possibly prolong survival in patients with mechanical tumour obstruction of the biliary tree by HCC.  相似文献   
38.
2-(1-Aryl-1-hydroxymethyl)- and 2-aroyl-DHAQ derivatives (DHAQ, 1,4-dihydroxy-9,10-anthraquinone), and 2-(1-aryl-1-hydroxymethyl)-ATO derivatives (ATO, anthracene-1,4,9,10-tetraone) were synthesized and their antitumor activities were determined. 2-(1-Aryl-1-hydroxymethyl)-DHAQ derivatives showed a stronger cytotoxicity compared to the series of 2-(1-hydroxyalkyl)-1,4-dihydroxy-9,10-anthraquinone derivatives. It was suggested that the presence of aryl group at the side chain accelerated the bioreductive activation leading to cell death. 2-Aroyl-DHAQ derivatives, despite their higher electrophilicity, revealed smaller cytotoxicity and antitumor activity (expressed by T/C value) than 2-(1-aryl-1-hydroxymethyl)-DHAQ derivatives. Thus, no consistent relationship between the electronic effect on aromatic side chain and the cytotoxicity was observed. ATO series exhibited a higher antitumor activity (T/C, 125 to approximately 218%), though their cytotoxicity was not further improved compared to that of 2-(1-aryl-1-hydroxymethyl)-1,4-dihydroxy-9,10-anthraquinones. They manifested no correlation between the cytotoxicity and the antitumor activity. In case of 2-[1-hydroxy-1-(4-propylphenyl)-methyl]-ATO, the most bioactive one in vivo among the same series, it showed an ED50 value of 10.2 mg/mL and a T/C value of 218%. It is assumed that the anthracene-1,4,9,10-tetraones after uptake into cellular tissues might be transformed to a cytotoxic metabolite(s).  相似文献   
39.
To determine the role of site of tumor implantation on tumor angiogenesis, we implanted gastric cancer cells in the orthotopic (stomach) and ectopic (subcutaneous) locations in nude mice. Tumors in the stomach demonstrated greater vascularization, higher levels of vascular endothelial growth factor (VEGF) expression, and greater proliferation compared with tumors in the subcutaneous tissues. These data suggest that the relationships among the expression of VEGF, vascularization, and proliferation of human gastric cancer cells are regulated by the organ microenvironment. In addition, VEGF may provide a target for anti-angiogenic therapy for gastric cancers.  相似文献   
40.
RELATIONSHIP BETWEEN CORNEAL DELLEN AND TEARFILM BREAKUP TIME   总被引:1,自引:0,他引:1  
The BUT of 51 strabismus patients were measured before and after operation. The average pre-op BUT was 28.75 seconds(10.96"-91.80"). The post-op BUT in all operated eyes were reduced significantly, no matter what procedures had been performed and whether dellen appeared or not(P<0.01). The BUT in the group complicated dellen reduced from 23.22"(pre-op) to 8.61"(post-op). The incidence of dellen was 22.54% in this study. The incidence of dellen after rectus resection procedure(47.75%) was much higher than that after rectus recession(5.13%)(P<0.01). This study showed that dellen was closelyre related to the BUT and occurred more often in the eyes on which resection procedure was performed. It is considered that excessive lacrimation and elevation of the bulbar conjunctiva near the limbus may disturb the stability of the precornea tearfilm and cause the tearfilm break up earlier. Local corneal dehydration and dellen formation may be caused by reduced BUT. The incidence of dellen after operation may be higher if the cornea was carefully observed.  相似文献   
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