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51.
 We have already presented a two-dimensional cell motility assay using a highly metastatic variant (L-10) of human rectal adenocarcinoma cell line RCM-1 as a motility model of tumour cells of epithelial origin. In this model, L-10 cells showed locomotion as a coherent sheet when stimulated with 12-O-tetradecanoylphorbol-13-acetate (TPA), and we called this type of movement ”cohort migration”. Electron and immunoelectron microscopic study of the migrating cell sheets demonstrated localized release from cell–cell adhesion only at the lower portion of the cells with loss of E-cadherin immunoreactivity, and this change was associated with increased tyrosine phosphorylation of the E-cadherin–catenin complex, including β-catenin. Cell–extracellular matrix (ECM) interactions involved in this TPA-induced cohort migration and their effect on tyrosine phosphorylation of the E-cadherin-catenin complex have now been investigated. L-10 cell cohort migration was almost completely inhibited by addition of Arg-Gly-Asp (RGD) peptide into the medium, and thus RGD dependent. Cohort migration was stimulated on type I and IV collagens, fibronectin (FN)- and laminin-coated substratum, but was inhibited by RGD only on FN-coated surface. By using immunofluorescent techniques, FN was demonstrated preferentially around migrating cells, and a protein synthesis inhibitor, cycloheximide, inhibited the migration by about 75%. FN produced by L-10 cells were found to be mostly EDA+ FN when analysed by RT-PCR. Moreover, anti-FN antibody, but not anti-vitronectin antibody, inhibited the TPA-induced cohort migration almost completely. Thus, it was likely that L-10 cells produced FN themselves and moved on the FN substrate in an RGD-dependent manner. However, stimulation of migration by type I collagen coating and inhibition by RGD treatment did not affect the tyrosine phosphorylation of the E-cadherin–catenin complex induced by TPA, indicating that cell–cell interactions were adjusted to suit cell migration, irrespective of the condition of cell–ECM adhesion, during TPA-induced cohort migration. Received: 31 December 1997 / Accepted: 2 April 1998  相似文献   
52.
Metastatic dissemination is the primary cause of death in ovarian cancer (OvCa) patients, and dissemination to pleural and peritoneal effusions is a common clinical event. Effusion samples were collected from 15 OvCa patients. Twenty-six samples were collected prospectively, two were archival, and eight were taken from patients with other malignancies. Twenty-nine samples were from malignant ascites, and seven specimens were pleural fluids. In addition, six ascites and two pleural fluids from noncancer patients were studied as effusion controls. Effusion supernatants were tested for migration-stimulation activity, using A2058 human melanoma cells as the index responder cell. Malignant samples induced a 400-1200% increase in migration. Sixty percent of the migration was inhibited by incubation of the malignant fluid with antifibronectin (FN) antibody, in contrast to 75% inhibition of control fluid-stimulated migration (P = 0.017). Gelatin zymography and Western blot analyses showed that latent and activated MMP-2 and MMP-9 collagenases, and tissue inhibitor of metalloproteinase-2 (TIMP-2) were present in all malignant fluids. Serial samples were taken from several patients, and a trend for correlation between MMPs and clinical behavior of the tumors was shown. Free TIMP-2 correlated with CA-125 levels in two patients for whom serial samples were available. The demonstration of promigratory and proinvasive activity in malignant effusions is consistent with their association with other metastatic disease in OvCa patients and their function as a haven for metastatic cells.  相似文献   
53.
For a reasonable analysis of sperm motility, consideration should be given to the morphology of the flagellum. Among various tail disturbances, the present paper describes a structural shaft defect that is characterized by variations in diameter, poor outline and/or lacking endpiece. Electron microscopical examinations, especially the negative staining technique, have shown that in addition to membrane alterations there is one essential cause for the limited extension of the outer dense fibres. This disturbance may be of genetic origin or due to toxic or inflammatory influences. Further molecular biological studies are required to detect the actual cause of this defect, for which there is so far no adequate therapy.  相似文献   
54.
我国正常生育力男子精浆的微量元素研究   总被引:12,自引:5,他引:7  
本文报告测试了68例正常生育力成年男子精浆中的锌、铜,铁等微量元素和镁,测试结果如下:锌130±5.64μg/ml,铜1.84±0.158μg/ml,铁0.801±0.104μg/ml,镁103.86±10.01μg/ml。所测得的数值均在正常范围内。在正常范围内的精液,精浆中的锌、镁含量与精液质量(精子密度和活动力)之间无显著差异。但铜的含量与精子活动度关系密切,含量高则活动度差,反之则活动度好。铁的含量与精子密度关系也十分密切,含量高时精子密度也高。  相似文献   
55.
Probiotics have been suggested to be effective for functional dyspepsia, but their effect on gastric motility is not clear. We evaluated the effect of Lactobacillus gasseri OLL2716 (LG21 strain) on mild to moderate delayed gastric emptying by a double-blind, parallel-group, placebo-controlled, randomized trial. Participants (n = 28) were randomly assigned to ingest LG21 strain-containing yogurt (LG21 strain group) or LG21 strain-free yogurt (placebo group) for 12 weeks. The 13C gastric emptying breath test was performed to measure the gastric emptying rate over time following ingestion of a liquid meal, and the time to reach the peak (Tmax) was used as an indicator of gastric emptying. We also measured the salivary amylase concentration, an indicator of autonomic dysfunction under stress. The per-protocol population (n = 27, male n = 4, female n = 23) was evaluated for efficacy. When a ≥30% reduction in the difference between participant’s Tmax and the Japanese mean Tmax was defined as an improvement, the odds ratio of improvement in delayed gastric emptying compared to placebo after 12 weeks was 4.1 (95% confidence interval, 0.8 to 20.2). Moreover, salivary amylase concentrations were significantly lower than in the placebo group, indicating an improvement in autonomic function. The present data were not enough to support the beneficial effects of the LG21 strain on delayed gastric emptying. However, if we define the odds ratio in further study investigated with a larger number of participants, LG21 strain might be expected to have some impact on delayed gastric emptying.  相似文献   
56.
目的 :探讨贲门失弛缓症患者食管动力学及气囊扩张的疗效。方法 :在内镜及X线监视下 ,用OTW气囊对 1 6例患者进行扩张 ,压力为 80~ 1 5 5kPa,维持 30s~1min ,反复 3~ 5次。对 7例患者在扩张前后使用瑞典产C—TD、PCPolyral压力测定仪作了下食管括约肌 (LES)压力、上食管括约肌 (UES)压力检测。结果 :1 6例患者临床症状显著改善 ,可进半流食和普食。 7例患者治疗前LES压力 (7 4± 1 4)kPa,扩张治疗LES压力 (3 4± 0 5 2 )kPa ,扩张治疗后LES压力较治疗前明显下降 (P <0 0 1 )。结论 :贲门失弛缓症存在明显食管动力障碍 ,气囊扩张疗效显著 ,采用渐进式气囊扩张方法 ,可避免食管穿孔的发生。  相似文献   
57.
下丘脑室旁核胃动素对胃运动的作用及其机制   总被引:3,自引:2,他引:1  
①目的 探讨室旁核胃动素对胃运动的影响 ,了解中枢胃动素参与胃运动调节的作用和机制。②方法 应用清醒动物核团微量注射记录胃运动 ,迷走神经切断 ,辣根过氧化物酶 (HRP)逆行追踪的方法 ,观察室旁核胃动素对胃运动的影响。③结果 清醒动物微量注射胃动素入室旁核可使胃运动的幅度和频率均增大 (t =2 .2 134~ 3.0 34 4,P <0 .0 5 ) ,膈下迷走神经切断后 ,室旁核注入胃动素对胃运动幅度及频率变化的影响消失 ;HRP逆行追踪实验中 ,迷走复合体注入HRP ,动物存活 2d后可在室旁核找到HRP标记细胞。④结论 下丘脑室旁核内胃动素参与胃运动的调节 ,下丘脑 延髓迷走复合体 迷走神经 胃轴可能是实现此作用的主要神经通路  相似文献   
58.
BackgroundThe aim of the study is to determine if barium esophagram (BE) alone is sufficient to diagnose esophageal dysmotility when compared to the gold standard, high-resolution manometry (HRM).MethodsThis is a retrospective review of patients that underwent laparoscopic fundoplication by two surgeons at a single institution from 10/1/2015-6/29/2019. Patients with large paraesophageal hernias and patients without both BE and HRM were excluded.ResultsForty-six patients met the inclusion criteria. BE was found to be concordant with HRM for esophageal motility in only 21 patients (46%). Setting HRM as the gold standard, BE had a sensitivity of 14% (95% CI: 5%–35%), specificity of 72% (95% CI: 52%–86%), PPV of 30% (95% CI: 11%–60%), and NPV of 50% (95% CI: 35%–66%). The accuracy was 46%, while a McNemar test showed p = 0.028.ConclusionTraditional BE should not be used in place of HRM for assessing pre-operative motility in patients undergoing anti-reflux surgery.  相似文献   
59.
The treatment of antibody-mediated spermagglutination by corticosteroidtherapy has a high incidence of side-effects and sperm washingis often followed by re-agglutination. The possibility of enzymaticdisagglutination was therefore investigated. In the first partof the study the effects of four proteases on sperm motility,vitality and longevity were evaluated. Subtilisin had prohibitivelydetrimental effects even at 10 U/ml. However, chymotrypsin (500U/ml), trypsin (500 U/ml) and papain (50 U/ml) had no adverseeffects. In the second series of experiments one or more ofthese latter three enzymes was found to disagglutinate spermatozoawhich had previously been incubated with sperm-agglutinatingantibody-positive sera in 87% of cases. Although further investigationis required, enzymatic disagglutination may be beneficial forthe treatment of immunologically mediated spermagglutination.  相似文献   
60.
摄入水温度对儿童胃动力的影响   总被引:2,自引:0,他引:2  
目的 研究温度对小儿胃动力的影响 .方法 健康儿童 40例 ,随机分为温水组及冷水组 ,每组 2 0例 ,温水组平均年龄为 8.8岁 ,冷水组 10 .5岁 ,两组摄入水的温度分别为37~ 40℃和 4~ 6℃ ,每例饮水 30 0 m L,在 B超下观察两组不同时间点的胃运动及排空情况 .结果  6 0 min时胃体蠕动频率以温水组 (2 .8± 0 .7)次· min- 1 快于冷水组 (1.5± 0 .5 )次· min- 1 ,但冷水组 90 %及 10 0 %胃腔排空时间明显短于温水组 ,分别为 (19.1± 3.1与 31.9± 7.1)和 (5 2 .5± 3.7与 5 9.5± 3.0 ) min.两组 10 % ,5 0 % ,90 %及 10 0 %胃窦排空时间分别为 (0 .8± 0 .8与 2 .8± 0 .3) ,(4 .5± 3.8与 17.4± 0 .4) ,(17.2± 2 .2与 41.7± 1.8)和 (4 9.2± 3.8与 5 6 .4± 3.6 ) min,冷水组均明显短于温水组 ,胃腔与胃窦残留率与上述结果完全相符 .结论 冷饮可使胃排空加速 ,频繁饮用低温饮料可能干扰胃的正常运动节律 .  相似文献   
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