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《Saudi Dental Journal》2021,33(7):620-627
ObjectiveThe goal of this study was to investigate the flexural strength, Young’s modulus and Weibull modulus of two heat-pressed and one CAD/CAM processed lithium disilicate (LD) ceramics.Material and methodsA total of 45 specimens with dimensions 16 × 4 × 1.2 ± 0.2 mm were fabricated out of three LD ceramics. For heat-pressed LD specimens, acrylate polymer blocks were cut and divided into two groups (n = 15 per group); a GC LiSi Press LD group (LP) and an IPS e.max Press group (EP). Specimens for each group were pressed corresponding to the manufacturer’s recommendations. For the CAD-CAM Group (EC), IPS e.max CAD blocks were cut to obtain specimens (n = 15) to the desired dimensions. Flexural strength and Young’s modulus tests were executed using a universal testing machine. A one-way ANOVA and post-hoc Tuckey’s tests were applied to analyze the results (p ≤ 0.05).ResultsRegarding flexural strength, the EC group showed higher statistically substantial difference than the EP and LP groups (p = 0.001), while there was no pronounced difference between the EP and LP groups (p = 0.065). For Young’s modulus test, all the three tested groups had no statistically substantial difference (p = 0.798).ConclusionThe IPS e.max CAD group had higher mechanical performance than the IPS e.max Press and GC LiSi Press groups.  相似文献   
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In lysosomal diseases, enzyme deficiency is caused by misfolding of mutant enzyme protein with abnormal steric structure that is expressed by gene mutation. Chaperone therapy is a new molecular therapeutic approach primarily for lysosomal diseases. The misfolded mutant enzyme is digested rapidly or aggregated to induce endoplasmic reticulum stress. As a result, the catalytic activity is lost. The following sequence of events results in chaperone therapy to achieve correction of molecular pathology. An orally administered low molecular competitive inhibitor (chaperone) is absorbed into the bloodstream and reaches the target cells and tissues. The mutant enzyme is stabilized by the chaperone and subjected to normal enzyme protein folding (proteostasis). The first chaperone drug was developed for Fabry disease and is currently available in medical practice. At present three types of chaperones are available: competitive chaperone with enzyme inhibitory bioactivity (exogenous), non-competitive (or allosteric) chaperone without inhibitory bioactivity (exogenous), and molecular chaperone (heat shock protein; endogenous). The third endogenous chaperone would be directed to overexpression or activated by an exogenous low-molecular inducer. This new molecular therapeutic approach, utilizing the three types of chaperone, is expected to apply to a variety of diseases, genetic or non-genetic, and neurological or non-neurological, in addition to lysosomal diseases.  相似文献   
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BackgroundHeat shock protein 70 (HSP70) is a significant cellular stress response protein that has intrinsic and extrinsic pathways to protect cells against apoptosis. It is one of the most induced proteins in cancer cells. The aim of the present study is to investigate the significant role of the HSP70 expression in Egyptian patients with breast cancer (BC) and its potential to be as a diagnostic and prognostic marker.Materials and MethodsHSP70 was examined in 155 cases in this prospective study; patients were subdivided into 3 groups: 60 patients with malignant metastatic disease, 60 patients with malignant non-metastatic disease, and 35 patients with benign lesions as control. HSP70 expression was detected using enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry (IHC).ResultsMost cases of breast cancer expressed HSP70 in both serum (98.3%) and tumor tissue (90%). A strong positive correlation was found between HSP70 IHC and ELISA (r = 0.811). The mean HSP70 levels, as detected in both patients’ serum by ELISA and tumor tissue by IHC, was significantly higher in patients with BC than in benign cases (P = .001). HSP70 was significantly higher in patients with metastatic BC than in those with non-metastatic BC (P = .001). HSP70 showed positive correlation with tumor size (pT stage) and number of lymph node metastases (P ≤ .001).ConclusionHSP70 is over-expressed in patients with metastatic and non-metastatic BC than in benign cases. A high level of HSP70 either in patient’s serum or in tumor tissue correlated significantly with advanced disease in patients with BC. This present study suggests that HSP70 can serve as a BC biomarker for early screening, diagnosis, and follow-up.  相似文献   
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目的 基于多重PCR技术,建立一种快速检测蜡样芽胞杆菌nhe、cytK和entFM 3种毒素基因的方法,并评价其效能。 方法 煮沸法提取蜡样芽胞杆菌DNA,以蜡样芽胞杆菌nhe、cytK和entFM特异性毒素基因作为靶基因,采用NCBI primer-BLAST 5.0软件设计特异性引物,优化反应体系。建立三重PCR检测体系,并检测其特异性、灵敏度和稳定性。 结果 煮沸法提取蜡样芽胞杆菌DNA,浓度为227 mg·L-1,纯度为1.50~1.60。采用多重PCR体系同时检测蜡样芽胞杆菌3种毒素致病基因,于退火温度56 ℃时,蜡样芽胞杆菌基因引物nhe499的扩增片段为499 bp,基因引物cytK191的扩增片段为191 bp,基因引物entFM363的扩增片段为363 bp。PCR体系扩增蜡样芽胞杆菌3种毒素基因后条带清晰明亮,且无非特异性条带,与金黄色葡萄球菌、大肠埃希菌和铜绿假单胞菌均无扩增,表明蜡样芽胞杆菌基因引物nhe499、cytK191和entFM363特异性强;3种引物在同一反应体系中互不干扰。灵敏度检测,多重PCR体系最低检测限可同时达到10-1 mg·L-1;稳定性检测,多重PCR体系自制备起每6个月检测稳定性一致。 结论 建立的多重PCR检测体系对于蜡样芽胞杆菌nhe499、cytK191和entFM363 3种毒素基因灵敏度高、特异性强,检测结果准确稳定,检测体系具有良好稳定性,适用于快速检出蜡样芽胞杆菌的3种不同致病毒素基因。  相似文献   
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Objective To observe the differential expression of high mobility group box-1 protein (HMGB1) in renal tissues of heat stroke mice models, and to explore its role in the pathogenesis of heat stroke associated acute kidney injury(HS-associated AKI). Methods According to random number table, 20 healthy male C57BL/6J mice were randomly divided into 2 groups, including normal control (n=10) and heat stroke group (n=10). The mice in heat stroke group were given with a 2-hour-exposure in biological simulation chamber (temperature 41℃, humidity 70%). Heat stroke was defined as anal temperature lasting more than 40 degrees Celsius. A 18F-deoxyglucose nuclide labeled vivo imaging was conducted with micro- positron emission tomography(PET)/computer tomography (CT). Serum creatinine was examined with blood example. In order to evaluate the pathological changes, HE stain was conducted with kidney tissue, and mitochondrial morphological changes in kidney tissue were observed by transmission electron microscopy. The expressions of HMGB1 and apoptosis inducing factor mitochondria associated 2 (Aifm2) were examined by immunohistochemical method, and the levels of HMGB1 and RAGE were examined by Western blotting. The cell apoptosis of renal tissue was detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay (TUNEL). The metabolomics of kidney tissue in mice were detected by liquid chromatography-mass spectrometry (LC-MS), and the pathway enrichment analysis was carried out by KEEG database. Results (1) The body temperature of the mice in heat shock group was significantly higher than that in normal control group 45 min after model establishment (P<0.05). The level of serum creatinine in heat shock group was significantly higher than that in normal control group (P<0.05), and the levels of 18F-deoxyglucose increased in skeletal muscle and visceral tissue of the mice in heat-shock group. (2) HE staining showed hemorrhage in collecting duct and tubular endothelial cell swelling, and mitochondrial swelling and deformation were observed by transmission electron microscopy in kidney tissue of the heat shock group. (3)Immunohistochemical method showed that the levels of Aifm2 and HMGB1 in heat shock group were higher (P<0.05). (4) Western blotting showed that the levels of HMGB1 and RAGE in heat shock group were higher than those in normal control group (P<0.05). (5) TUNEL showed that the number of cells with positive stain in kidney tissue of the heat shock group was higher than that in normal control group (P<0.05). (6) Between normal control group and heat shock group, 136 differential metabolites were detected in kidney tissues. After analysis by KEGG database, pathway abnormalities such as unsaturated fatty acid metabolism disorder may be associated with HS-associated AKI, and many differential metabolites such as adrenic acid may be important regulatory points in the pathogenesis. Conclusion Acute kidney injury is a common complication of heat shock. It may be related to the dysfunction of renal mitochondria and activation of apoptotic pathway caused by systemic hypercatabolism, which may be related to the disorder of unsaturated fatty acid metabolism and activation of HMGB1. Some differential metabolites may be of high value in HS- associated AKI studies.  相似文献   
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目的 观察穴位热痛刺激治疗无先兆偏头痛患者的近期镇痛疗效。 方法 采用随机数字表法将120例无先兆偏头痛患者分为观察组及对照组,每组60例。对照组患者给予西比灵口服,每晚1次,每次5 mg,治疗4周为1个疗程。观察组患者在对照组干预基础上辅以穴位热痛刺激,取穴风池、率谷、阳陵泉、外关、太阳、印堂,选用Pathway疼痛及感觉评估系统配置的圆形刺激器,当刺激器加热至54.5 ℃时发放可调节脉冲热刺激,单个脉冲热刺激其脉宽为0.3 s,刺激间隔10 s,每个穴位连续刺激5次后换下一穴位,各穴位循环交替刺激,共治疗20 min,每日治疗1次,治疗4周为1个疗程。记录治疗前、后2组患者头痛发作频率、持续时间、疼痛视觉模拟评分(VAS)、头痛伴随症状评分、偏头痛特异生活质量问卷量表(MSQ)评分,并对比2组患者近期疗效差异。 结果 治疗后观察组患者头痛发作频率[(1.27±0.13)次/月]、头痛持续时间[(2.51±0.22)分钟/次]、疼痛VAS评分[(0.43±0.08)分]、头痛伴随症状评分[(0.21±0.20)分]、MSQ功能受限评分[(79.0±10.2)分]、功能障碍评分[(82.6±10.3)分]及情感评分[(85.2±10.5)分]均较治疗前及对照组明显改善(均P<0.05);另外治疗后观察组患者总有效率(95.0%)亦显著优于对照组水平(80.0%),组间差异具有统计学意义(P<0.05)。所有患者在治疗期间其心率、血压均未出现不良反应,热痛刺激部位无感染、红肿等异常表现。 结论 穴位热痛刺激治疗无先兆偏头痛患者近期疗效显著,并且治疗过程安全可靠、副反应少,为偏头痛患者提供了一种新的治疗方法,值得临床推广、应用。  相似文献   
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热敏灸作为一种新型的灸疗方法,《医宗金鉴》中述“凡灸诸病,必火足气到,始能求愈”,故热敏灸讲究“敏消量足”,举一临床顽固性呃逆病案加以细说。  相似文献   
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BackgroundBiliopancreatic diversion (BPD) is more effective than Roux-en-Y gastric bypass (RYGB) on both insulin resistance and diabetes.ObjectivesBecause the major difference between the 2 procedures resides in the length of jejunal bypass, we investigated the role of the jejunum in insulin resistance.SettingUniversity hospital in Italy.MethodsInsulin sensitivity (IS) and secretion were measured before and 4 weeks after RYGB or BPD in 16 patients. A translational study was also conducted in 6 pigs, by isolating a jejunal loop with its vascular and nerve supply (Thiry-Vella loop [TVL]). TVL was doubly stomatized and bowel continuity restored by a side-to-side jejuno-jejunostomy. At baseline and 4 weeks postoperatively a glucose bolus was injected either in the stomach or in the TVL. Whole-body IS and jejunal heat shock proteins (HSPs) were measured. Primary porcine hepatocyte cultures were incubated with plasma or individual HSPs.ResultsWhole-body IS increased from 353.5 ± 26.7 to 442.0 ± 37.4 (P < .05) after RYGB and from 312.4 ± 14.9 to 441.2 ± 15.9 mL/m−2/min−1 (P < .001) after BPD. Hepatic IS was unchanged after RYGB, while it increased from .3 ± .01 to .4 ± .1 (μM/pM) – 1 (P < .01) after BPD. Total insulin secretion rate remained unchanged after RYGB but decreased (from 58.3 ± 23.6 to 33.1 ± 7.8 nmol/m−2, P < .05) after BPD. Jejunectomy in pigs enhanced IS (.3 ± .01 versus .2 ± .01 mM/pM, P < .001), while injection of glucose into TVL reduced it (.1 ± .01 versus .3 ± .01 mM/pM, P < .0001). The jejunum secreted HSPs, Hsp70, and GRP78, which impaired insulin signaling in hepatocyte cultures.ConclusionsThis study shows that jejunal bypass in both humans and pigs improves IS. Injection of glucose into the TVL in pigs determines insulin resistance. In response to glucose, the jejunum secretes HSPs that impair insulin signaling.  相似文献   
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