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乙肝疫苗接种无、弱应答与遗传因素关系   总被引:35,自引:2,他引:33  
从现场流行病学和实验研究两方面探讨乙肝疫苗接种无、弱应答是否与遗传因素有关。方法健康小学生634名接种3针血源性乙肝疫苗,共筛选出29我、弱应答,同时选择30名强应答作为对照,对无、弱应答和强应答一级亲属中符疫苗接种条件的对象接种3针乙肝疫苗,观察免疫反应。另外,从无、弱应答和强应答中选择部分对象检测了人类白细胞抗原(HLA)-A,B,C,DR,DQ座位等位基因。结果小学生无、弱应答率为  相似文献   
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Resveratrol (Res) is a naturally occurring phytoalexin with apoptotic and inducing-glob effects in leukemic cells, but the potential induction of erythroid differentiation in cells is not fully understood. Here, we investigated the effects of Res on human erythro-megakaryoblastic leukemia cell line K562. Among the treated cells, proliferation was inhibited and the occurrence of cell apoptosis and cell death were detected. Erythroid differentiation assay was explored, and we found that Res could increase the expression of glycophorin A (GPA), HBA1, HBB, and γ-globin genes and enforced the expression of GPA, CD71, and Band3 proteins. Res also induced K562 cell autophagy when the concentration of Res was increased up to 50 or 100 μM. Our findings suggested that Res possesses the potency not only inducing apoptosis but also inducing erythroid differentiation and autophagy in K562 cells. These results provide that Res may be a therapeutic candidate for chronic myelogenous leukemia treatment.  相似文献   
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Eugenol, a natural phenolic constituent of clove oil, has a wide range of applications in medicine as a local antiseptic and anesthetic. However, the effect of eugenol on human glioblastoma is unclear. This study examined whether eugenol elevated intracellular free Ca2+ levels ([Ca2+]i) and induced apoptosis in DBTRG-05MG human glioblastoma cells. Eugenol evoked [Ca2+]i rises which were reduced by removing extracellular Ca2+. Eugenol-induced [Ca2+]i rises were not altered by store-operated Ca2+ channel blockers but were inhibited by the PKC inhibitor GF109203X and the transient receptor potential channel melastatin 8 (TRPM8) antagonist capsazepine. In Ca2+-free medium, pretreatment with the endoplasmic reticulum Ca2+ pump inhibitor thapsigargin (TG) or 2,5-di-tert-butylhydroquinone (BHQ) abolished eugenol-induced [Ca2+]i rises. The phospholipase C (PLC) inhibitor U73122 significantly inhibited eugenol-induced [Ca2+]i rises. Eugenol killed cells which were not reversed by prechelating cytosolic Ca2+ with 1,2-bis(2-aminophenoxy) ethane-N,N,N′,N′-tetraacetic acid-acetoxymethyl ester (BAPTA-AM). Eugenol induced apoptosis through increasing reactive oxygen species (ROS) production, decreasing mitochondrial membrane potential, releasing cytochrome c and activating caspase-9/caspase-3. Together, in DBTRG-05MG cells, eugenol evoked [Ca2+]i rises by inducing PLC-dependent release of Ca2+ from the endoplasmic reticulum and caused Ca2+ influx possibly through TRPM8 or PKC-sensitive channels. Furthermore, eugenol induced the mitochondrial apoptotic pathway.  相似文献   
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Background

The risk of colorectal cancer (CRC) in chronic kidney disease (CKD) patients relative to the general population is unknown. The aim of this population-based study was to investigate the risk of CRC in patients with CKD.

Methods

The study cohort included patients aged ≥18 years diagnosed with CKD between 2004 and 2005 (n = 15,975). The comparison cohort (n = 79,875) included five randomly selected age- and gender-matched controls for each patient in the study cohort. All the subjects were followed up from the date of cohort entry until they developed CRC or until the end of 2006.

Results

We identified 15,975 patients with a diagnosis of CKD who matched the inclusion criteria. A total of 460 patients developed CRC during the study period, of whom 116 were from the CKD cohort and 344 were from the comparison cohort. After adjusting for potential confounding factors, the CKD patients not undergoing dialysis were independently associated with a greater risk of CRC (hazard ratio, 1.79; 95 % confidence interval [CI] 1.41–2.27). The overall incidence rate of CRC was 341 per 100,000 person-years for CKD patients not undergoing dialysis, compared to 174 per 100,000 person-years. The age-matched hazard ratio of CRC after excluding dialysis patients was 1.64 (95 % CI 1.27–2.11) in patients 50 years and older, and 3.7 (95 % CI 1.83–7.49) in patients younger than 50 years.

Conclusions

This population-based cohort study indicated that CKD patients not requiring dialysis have an increased risk of CRC compared to the general population, independent of comorbidities.  相似文献   
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There are reports of an association between benign paroxysmal positional vertigo and hyperuricemia. We sought to determine the risk of vertigo among patients with gout compared with the general population, using a nationwide Taiwanese population-based claims database. Our study cohort consisted of patients with a diagnosis of gout disorders in 2004 (N = 18 773). Four age- and gender-matched controls for every patient in the study cohort were selected using random sampling as the comparison cohort (N = 75 092). All subjects were followed from the date of cohort entry until they developed vertigo or to the end of 2006. Cox proportional hazard regressions were performed to evaluate the 3-year vertigo-free survival rates. Of the total sample, 2563 (incidence, 10.09 per 1000 person-years) had vertigo during the 3-year follow-up period: 570 (incidence, 11.78 per 1000 person-years) from the study cohort and 1993 (incidence, 9.69 per 1000 person-years) from the comparison cohort. The adjusted hazard ratios (HR) of peripheral and central vertigo in patients with gout compared with controls during the 2–3-year follow-up were 1.17 (95% confidence interval [CI] = 1.05–1.29, p = 0.003) and 1.08 (95% CI = 0.86–1.36, p = 0.53), respectively. This is the first population-based study performed to suggest that patients with gout may have an increased risk of peripheral vertigo but not central vertigo. Benign paroxysmal positional vertigo may be the reason for the observed association; however, future studies are required to further ascertain the relationship between gout and the various causes of peripheral vertigo.  相似文献   
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目的:评价胶原蛋白(Collagen)的细胞相容性;研究胶原蛋白(C)与大鼠胎脑神经细胞(FBN)复合体(C-FBN)脑内移植对脑损伤的修复作用。方法:将大鼠FBN与胶原蛋白联合体外培养,进行光镜、扫描电镜观察。并将体外联合培养3~5d的C-FBN(移植前48h培养液中加入BrdU)移植到大脑皮质损伤模型的大鼠脑损伤部位,术后3,6,10,15及30d光镜、BrdU免疫细胞化学染色(ICC)、透射电镜观察脑组织对移植物的反应、移植细胞生长状态及载体在体内的降解情况等。结果:胶原蛋白对FBN生长无不良影响;脑组织对移植物无明显的免疫排斥反应;胶原蛋白与周围脑组织整合好,有血管长入移植物中;载体内有大量存活神经细胞,而且术后各时段都检出BrdU阳性细胞;移植区有突触形成;胶原蛋白海绵吸收、降解快,可诱导组织再生。结论:胶原具有良好的细胞相容性和组织相容性,是神经组织工程的一种较为理想的生物载体材料;生物材料与胎脑神经细胞联合培养移植是治疗脑损伤较有前途的新方法。  相似文献   
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Porcine epidemic diarrhea virus (PEDV) is a coronavirus that causes serious and highly contagious enteric disease in swine worldwide. In this study, we constructed a recombinant baculovirus (S-Bac) expressing full-length spike protein of the virulent epidemic genotype 2b (G2b) PEDV strain for serological studies of infected pigs. We found that most spike-specific antibodies produced upon PEDV infection in pigs are conformation-specific and they could be detected on S-Bac-infected insect cells by immunofluorescent assay, but they were insensitive to Western blot analysis, the typical method for antiserum analysis. These results indicated that spike conformation is crucial for serum recognition. Since it is difficult to purify trimeric spike membrane protein for conventional enzyme-linked immunosorbent assay (ELISA), we used S-Bac to generate a novel cell-based ELISA for convenient PEDV detection. We analyzed 100 pig serum samples, and our cell-based ELISA exhibited a sensitivity of 100%, a specificity of 97%, and almost perfect agreement [Cohen’s kappa coefficient value (κ) = 0.98] with immunocytochemical staining results. Our cell-based ELISA rapidly presented antigen for proper detection of conformation-specific antibodies, making PEDV detection more convenient, and it will be useful for detecting many viral diseases in the future.  相似文献   
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