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排序方式: 共有1445条查询结果,搜索用时 102 毫秒
1.
Objective: To investigate the association between the diversity of urease gene and urease activity of clinical isolates of Helicobacter pylori (H. pylori). Methods: Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) of urease gene and rapid urease activity test were used to study the urease activity of different clinical isolates of H. pylori. Results: H. pylori clinical isolates were divided into 4 types according to their PCR-RFLP results of urease gene and urease activity. Type Ⅰ , possessing strong urease activity (0. 11) and presented 1 fragment of 1. 7 kb by PCR-RFLP, had close relations with gastric ulcer; type Ⅱ , with the weakest urease activity (0. 07) and 2 fragments (1. 3 and 0. 4 kb respectively) , was associated with duodenal bulb ulcer; type Ⅲ , with the strongest urease activity (0. 12) and 2 fragments (0. 4 and 0. 17 kb) with or without 1 fragment (0. 23 or 0. 37 kb) , was responsible for gastritis; type Ⅳ , with weak urease activity (0. 09) and 2 fragments 相似文献
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CT扫描对股骨头坏死的诊断价值(CT片与X线片对比分析) 总被引:1,自引:0,他引:1
为了检验CT扫描对股骨头坏死的诊断价值,我们对病理证实的33例病人,42例股骨头坏死的X线平片与CT片进行了对比分析。37例股骨头坏死由CT扫描检出(88.1%),其中仅有26例股骨头坏死从X线平片中检出(61.9%)CT优于X线平片。但仍有5个早期股骨头坏死是靠放射核素扫描得以确诊,因而早期股骨头坏死CT扫描诊断尚存在一定限制。 相似文献
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湖北人群Toll样受体4基因多态性研究 总被引:5,自引:0,他引:5
目的 研究湖北人群Toll样受体4(TLR4)Asp299Gly和Thr399Ile基因多态性分布特征。方法 采用等位基因特异性聚合酶链反应(ASPCR)-限制酶片断长度多态性(RFLP)检测TLR4 Asp299Gly和Thr399 Ile基因多态性。结果 在所有的253例中国湖北人群样本中,没有检测到TLR4 Asp299Gly和Thr399Ile基因多态性存在。结论 TLR4基因多态性在不同地区和人群发生的频率是不同的,与白种人相比,中国湖北人群的TLR4Asp299G1y和Thr399Ile的基因多态性非常罕见。 相似文献
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小儿高胆固醇血症的筛查和饮食治疗 总被引:2,自引:0,他引:2
动脉粥样硬化引起的心血管疾病是人类的主要死因之一。大量研究表明,动脉粥样硬化性病变始于儿童时期,高胆固醇血症是促使其发展的主要因素。降低血清胆固醇浓度可减少发生冠心病的危险性。依据美国国家胆固醇教育计划专家委员会制定的诊断标准,对2岁以上有阳性家族史的儿童进行选择性血脂筛查,并对高胆固醇血症儿童进行饮食治疗。研究证实,美国心脏病协会和美国国家胆固醇教育计划专家委员会推荐的饮食控制方案可有效降低血清总胆固醇和低密度脂蛋白胆固醇水平。只要提供足够的热量和营养素,适当的低胆固醇饮食不会影响儿童的生长发育。 相似文献
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湖南省乙肝病毒基因型分布及临床意义 总被引:1,自引:0,他引:1
目的 :研究湖南省乙肝病毒 (HBV)基因型分布及临床意义。方法 :选择湖南省HBVDNA阳性慢性乙肝病人共 185例 ,其中病毒携带者 (ASC) 4 2例 ,慢性轻、中度肝炎 (CH) 38例 ,重型肝炎 (FHF) 80例 (伴有肝硬化者 4 9例 ) ,肝细胞癌 (HCC) 2 5例 ,采用聚合酶链反应 限制性片段长度多态性 (PCR RFLP)方法检测HBV基因型。结果 :基因型B136例 (73.5 % ) ,基因型C 4 9例 (2 6 .5 % )。基因型B在FHF中占绝对优势 (83.7% ) ,其次为HCC(76 % ) ,与ASC(5 7.1% )比较 ,差异有显著性 (P <0 .0 1)。与基因型B相比 ,基因型C在垂直传播感染者中多见 (38.8%与 13.2 % ,P <0 .0 0 1) ;HBeAg阳性率明显增高 (5 7.1%与 30 .9% ,P <0 .0 0 1) ;抗HBe阳性率明显下降 (36 .9%与 6 6 .2 % ,P <0 .0 0 1)。与基因型C相比 ,基因型B感染者ALT水平明显增高 (2 6 4 .5± 2 5 6 .5与 10 0± 12 0 .6 ,P <0 .0 0 1)。结论 :湖南省存在乙肝病毒基因型B和基因型C ;基因型B为优势基因型并与肝脏疾病活动性相关 ,基因型C与母婴垂直传播感染有关 相似文献
7.
Objective To investigate whether low-protein diet has protective effect on the progression of renal interstitial fibrosis in rats with cyclosporine A (CsA)-induced nephropathy. Methods Eighteen male Sprague-Dawley rats were randomly divided into three groups (6 rats in each group). The rats in control group (C group) received common diet; in model group (M group) low-salt diet; in intervention group (Ⅰ group) low-salt and low-protein diet. After diet adaptation period of one week, the rats in C group received subcutaneous injection of olive oil 1 mg/kg daily for 5 weeks, while M group and Ⅰ group subcutaneous injection of CsA (diluted into 25 g/L with olive oil) 1 ml/kg for 5 weeks. All the rats were sacrificed at the end of the 5th week. The food-intake and body weight were measured daily. The creatinine clearance (Ccr) was examined before rats were sacrificed. The semi-quantitative pathological analysis on kidney sections was performed. The mRNA and protein expression of transforming growth factor-β1 (TGF-βI) and type Ⅰ collagen (Col Ⅰ) in kidney tissue was determined with real time PCR and immunohistochemical staining, respectively. Results The food-intake and body weight of rats in M and I groups were significantly lower than those in C group (P<0.05). Compared with C group, the Ccr levels in M and Ⅰ groups were significantly reduced [(0.65±0.15) ml/min, (0.40+0.13) ml/min vs (1.55±0.29) ml/min, P<0.05], the relative fibrosis areas of kidney interstitium in M and I groups were significantly increased (3.60%±0.46%, 3.26%±0.75% vs 0.44%±0.24%, P<0.05), the mRNA and protein expression of TGF-β1 in M and I group was significantly up-regulated (by 2.6 and 3.1 times in mRNA and by 1.5 and 1.6 times in protein, respectively, P<0.05), and the mRNA and protein expression of Col Ⅰ in M and I groups was also significantly up-regulated (by 3.0 and 3.5 times in mRNA and by 2.3 and 2.1 times in protein, respectively, P<0.05). There were no significant differences between M and I groups in every parameters above-mentioned except the rat body weight and Ccr. Both the body weight and Ccr in Ⅰ group were significantly lower than those in M group (P<0.05). Compared with C group, the urine osmotic pressure in M group and in I group were deceased (for M group, P>0.05; for I group, P<0.05). Compared with C group, the serum cholesterol levels in M and I groups were significantly increased (P<0.05), and the serum phosphorus level in I group was significantly decreased (P<0.05). The levels of serum albumin and serum calcium of all three groups had no statistical differences (P>0.05). Conclusion Low-protein diet has no renoprutective effects on the rat model of cyclosporin A nephropathy, on the contrary, may induce body weight loss. 相似文献
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面对医学影像科学技术的飞速发展和各种新诊疗技术的广泛应用,如何不断提高X线诊断质量,为临床提供确有参考价值的诊断意见,是值得我们探讨的问题。 相似文献