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991.
严重会阴部挫裂伤治疗方案探讨   总被引:2,自引:0,他引:2  
目的探讨会阴部严重挫裂伤治疗的合理方案,提高治疗质量。方法通过回顾我院收治的18例会阴部严重挫裂伤病例的治疗过程,总结与分析了这类损伤不宜Ⅰ期修复的原因和结肠造瘘术在治疗中的作用。结果本组18例会阴部严重挫裂伤,均在早期清创缝合修复,后因感染,同时并发不同程度、不同范围的皮肤坏死而造成缺损和伤口裂开。均需再次清创、皮瓣转移和植皮予以修复。在此过程中,采用结肠造瘘术来控制创面感染和预防创面继发感染,收到了良好效果。结论严重会阴部挫裂伤创面的早期治疗,特别是污染重、挫伤重、损伤范围大的,均不宜Ⅰ期修复。早期行结肠造瘘术对预防和控制会阴部创面感染能起到重要的作用。  相似文献   
992.
目的:初步探讨在异基因造血干细胞移植(HSCT)中发生移植物抗宿主病(GVHD)患者DC40L表达的变化以及意义。方法:HSCT治疗重型β-地中海贫血(n=12)和遗传性溶血性贫血(n=1)成功植入的儿童患者,其中脐血移植(UCBT)8例,异基因外周血造血干细胞移植(allo-PBSCT)5例,在移植前、移植后发生GVHD时采用流式细胞仪检测和比较外周血中CD40L和CD40的表达。结果:3例UCBT无GVHD,其余均发生了Ⅰ-Ⅳ度急性GVHD。急性GVHD发生时CD4^ CD40L^ 和CD8^ CD40LT细胞表达明显升高,allo-PBSCT者更明显;慢性GVHD发生时患者的CD40L^ 、CD25^ 和CD69^ 在CD4^ 和CD8^ T细胞上的表达亦增加。CD19^ CD40^ B细胞的表达在UCBT和allo-PBSCT的3个月内则一直处于低于正常的水平。结论:CD40L高表达与GVHD的发生相关,提示CD40-CD40L共刺激途径在GVHD的发生中可能起着重要作用。  相似文献   
993.
观察妥布霉素伤用凝胶的体外抗菌活性 ,为临床应用提供试验依据。采用平皿二倍稀释法测定了妥布霉素伤用凝胶对临床分离的 12 0株临床常见的革兰氏阳性及革兰氏阴性菌的体外抗菌作用。以对青霉素敏感的金葡菌、表葡菌、对庆大霉素敏感的大肠杆菌、敏感绿脓杆菌的作用为最强 ,MIC50 均为 0 2 5mg/L。妥布霉素伤用凝胶抗菌谱较广 ,对试验中的革兰氏阳性及革兰氏阴性菌均具有较强的杀灭或抑制作用 ,显示出较好的抗菌活性。  相似文献   
994.
BACKGROUND: RANTES promoter polymorphisms were found associated with asthma/atopy in some studies but not others, possibly reflecting the genetic heterogeneity among different ethnicities and different asthma severity. OBJECTIVE: The purpose of this investigation was to test the genetic association between the RANTES -28C/G and -403G/A polymorphisms and asthma/atopy in a cohort of Chinese children, with particular emphasis on those patients who had experienced life-threatening asthma attacks. METHODS: Forty-eight children with near-fatal asthma, 134 children with mild-to-moderate asthma, 69 children with allergic disorders but no asthma, and 107 nonasthmatic nonatopic control children were genotyped through use of a PCR-based assay. RESULTS: No significant difference was demonstrated for frequency of the RANTES -28C/G polymorphism when the mild-to-moderate asthma, atopic/nonasthmatic, and normal control groups were compared. The RANTES -28G allele was present in a significantly higher proportion of the children with near-fatal asthma compared with the nonasthmatic nonatopic controls (odds ratio, 2.93 [1.41-6.06]; P =.006) and the children with mild-to-moderate asthma (odds ratio, 3.52 [1.73-7.16]; P =.001). The frequency of -28G allele carriage correlated with asthma severity. The RANTES -28G allele was also associated with an increased blood eosinophil count and a higher degree of bronchial hyperresponsiveness. The RANTES -403G/A polymorphism did not influence asthma/atopy susceptibility, blood eosinophil count, or bronchial hyperresponsiveness. Interestingly, a higher frequency of -403A allele carriage was observed in the moderate asthma subgroup compared with the mild asthma analog. CONCLUSIONS: We conclude that the RANTES -28C/G polymorphism exacerbates asthma severity, representing a genetic risk factor for life-threatening asthma attacks in Chinese children. In addition, the linkage disequilibrium between these 2 polymorphisms is a potential confounder that must be considered in the design and interpretation of RANTES gene association studies.  相似文献   
995.
This article describes the identification of a novel locus (DFNB39) responsible for an autosomal recessive form of hearing loss segregating in a Pakistani consanguineous family. The hearing impaired members of this family present with profound prelingual sensorineural hearing impairment and use sign language for communications. Linkage was established to microsatellite markers located on chromosome 7q with a maximum multipoint lod score of 3.8. The region of homozygosity spans a 19 cM region that is bounded by markers D7S3046 and D7S644.  相似文献   
996.
建立毛细管电泳分离分析多巴胺和 5一羟色胺的方法。采用自由区带电泳法 (CZE) ,4 0mmol/L硼砂缓冲液 2 0PSI气压进样 5s ,定电流 75 μA分离 10min ,二极管阵列PDA检测器检测 ,应用 2 0 0nm检测波长 ,结果显示两种物质完全分离。  相似文献   
997.
目的 构建HPV 18 L1-E6,L1-E7嵌合基因的表达载体,并在CHO细胞中表达。方法 克隆HPV18 L1-E6和L1-E7基因,插入中介载体pGEMT-Easy中并测序鉴定。采用PCR定点突变法,突变L1-E6,L1-E7基因序列中与转化作用相关的位点,分别与L1基因连接后插入真核表达载体pVAX1,构建真核表达质粒pVAX-1L1 E6Mxx,L1E7Mxx。用磷酸钙沉淀法,转染CHO细胞,以抗HPV-18L1,抗E6和抗E7特异性单克隆抗体(mAb)做ELISA和免疫细胞化学法检测。结果 ELISA检测显示,转染各种pVAX1-LIE6Mxx-L1E7Mxx融合蛋白表达质粒的细胞提取物的P-N值均>2.1;免疫细胞化学检测,在胞浆,胞核可见棕黄色颗粒。结论 我建的pVAX1-L1E6Mxx-E7Mxx融合蛋白质表达质粒,可在转当细胞内表达相应的L1-E6Mxx和L1-E7Mxx蛋白,为今后进行DNA疫苗的研究奠定了基础。  相似文献   
998.
999.
The major consequence of long-term diabetes is the increased incidence of disease of the vasculature. Of the underlying mechanisms leading to disease, the accumulation of advanced glycation end products (AGEs), resulting from the associated hyperglycemia, is the most convincing. Interaction of AGEs with their receptor, RAGE, activates numerous signaling pathways leading to activation of proinflammatory and procoagulatory genes. Studies in rodent models of macro- and microvascular disease have demonstrated that blockade of RAGE can prevent development of disease. These observations highlight RAGE as a therapeutic target for treatment of diabetic vascular disease.  相似文献   
1000.
Wu X  Gao J  Yan J  Owyang C  Li Y 《Journal of neurophysiology》2004,91(4):1734-1747
Circulating glucose levels significantly affect vagal neural activity, which is important in the regulation of pancreatic functions. Little is known about the mechanisms involved. This study investigates the neural pathways responsible for hypoglycemia-induced vagal efferent signaling to the pancreas and identifies the neurotransmitters involved. Vagal pancreatic efferent nerve activities were recorded in anesthetized rats. Insulin-induced hypoglycemia, a decrease of blood glucose levels from 114 +/- 5 to 74 +/- 6 mg dl(-1), stimulated an increase in pancreatic efferent nerve firing from a basal rate of 1.1 +/- 0.3 to 19 +/- 3 impulses 30 s(-1). In contrast, vagal primary afferent neuronal discharges recorded in the nodose ganglia were unaltered by systemic hypoglycemia. Vagal afferent rootlet section plus splanchnicotomy had no effect on hypoglycemia-induced vagal efferent firing, suggesting a central site of action. Decerebration reduced the increase in nerve firing stimulated by hypoglycemia from 21 +/- 4 to 9.6 +/- 2 impulses 30 s(-1). Chemical ablation of the lateral hypothalamic area, but not the arcuate nucleus, inhibited pancreatic nerve firing evoked by hypoglycemia. Microinjection of the orexin-A receptor antagonist SB-334867 into the dorsal motor nucleus of the vagus (DMV) inhibited pancreatic nerve firing evoked by insulin-induced hypoglycemia by 56%. In contrast, injection of orexin-A (20 pmol) into the DMV elicited a 30-fold increase in pancreatic nerve firing. We concluded that systemic hypoglycemia stimulates pancreatic efferent nerve firing through a central mechanism. Full expression of pancreatic nerve activities during hypoglycemia requires both the forebrain and the brain stem. In addition to activating neurons in the brain stem, central neuroglucopenia activates subpopulations of neurons in the lateral hypothalamic area that contain orexin. The released orexin acts on DMV neurons to stimulate pancreatic efferent nerve activities and thus regulate pancreatic functions.  相似文献   
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