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1.
Deoxynivalenol (DON) has broad toxicity in animals and humans. In this study the impact of DON treatment on apoptotic pathways in PC12 cells was determined. The effects of DON were evaluated on (i) typical indicators of apoptosis, including cellular morphology, cell activity, lactate dehydrogenase (LDH) release, and apoptosis ratio in PC12 cells, and on (ii) the expression of key genes and proteins related to apoptosis, including Bcl-2, Bax, Bid, cytochrome C (Cyt C), apoptosis inducing factor (AIF), cleaved-Caspase9, and cleaved-Caspase3. DON treatment inhibited proliferation of PC12 cells, induced significant morphological changes and apoptosis, promoted the release of Cyt C and AIF from the mitochondria, and increased the activities of cleaved-Caspase9 and cleaved-Caspase3. Bcl-2 expression decreased with increasing DON concentrations, in contrast to Bax and Bid, which were increased with increasing DON concentration. These data demonstrate that DON induces apoptosis in PC12 cells through the mitochondrial apoptosis pathway.  相似文献   
2.
According to conservative estimates, >230 million people are infected with schistosomiasis,which becomes one of the most common parasitic diseases. This study focuses on investigating in vivo and in vitro effects of mmu-miR-92a-2-5p in Schistosoma japonicum-induced liver fibrosis by targeting TLR2. Through bioinformatic analysis, the overexpression of TLR2 and the down-regulation of mmu-miR-92a-2-5p were revealed in the progression of S. japonicum-induced liver fibrosis. BALB/C mice were taken advantage to construct normal control and schistosomiasis liver fibrosis (SLF) model. The mice in model groups were transfected recombinant lentivirus (Lenti-mmu-miR-92a-2-5p or Lenti-NC) to alter the expression of mmu-miR-92a-2-5p in vivo. HE and Masson staining were employed to observe the pathological changes and collagenous fibrosis. QRT-PCR showed that mmu-miR-92a-2-5p was decreased while TLR2 was elevated in the infected groups. However, lenti-mmu-miR-92a-2-5p group could inhibit liver fibrosis. Then the effect of mmu-miR-92a-2-5p on S. japonicum-induced liver fibrosis including cell apoptosis rates, proliferation and proteins related to liver fibrosis was examined in NIH-3T3 mouse embryonic fibroblasts. Moreover, the association between mmu-miR-92a-2-5p and TLR2 was detected by dual-luciferase reporter gene assay and the expression of cytokines IL-4, IFN-γ and TNF-α in SLF model was detected by ELISA. Further, the knockout of TLR2 in C57BL/6J mice was used to confirm the association between mmu-miR-92a-2-5p and TLR2. Thus, these findings demonstrated that mmu-miR-92a-2-5p inhibited S. japonicum-induced liver fibrosis by targeting TLR2 in vitro and in vivo.  相似文献   
3.
《世界针灸杂志》2023,33(3):237-243
ObjectiveTo observe the effects of long-snake moxibustion on the hypothalamic-pituitary-adrenocortical (HPA) axis and hepatic 11β-hydroxy steroid dehydrogenase type 1 (11β-HSD1) expression in rats with kidney yang deficiency to provide a basis for later in-depth exploration of the action mechanism of long-snake moxibustion on such rats.MethodsFifteen SPF-grade, male, SD rats were randomly divided into a blank control group, a model group, and a long-snake moxibustion treatment group, with five rats in each group. Hydrocortisone powder (30 mg/kg) was administered by gavage at a volume of 10 mL/kg to prepare the rat model of kidney yang deficiency. After successful modeling, the rats in the long-snake moxibustion treatment group underwent long-snake moxibustion treatment every other day (along the governor vessel from Dazhui (GV14) to Shenshu(BL23), for a period of 14 days. The remaining two groups were secured in the same way as the long-snake moxibustion treatment group, although they did not receive any treatment. The body weight, rectal temperature, and spontaneous activity count of the rats, as well as serum levels of corticotropin releasing hormone (CRH) and corticosterone (CORT) were detected by ELISA before modeling, after modeling, and after treatment. The amount of 11β-HSD1 protein in rat liver was determined by immunohistochemistry and Western blot analysis.ResultsCompared with the rats in the blank control group, those in the model group exhibited a significant decrease in the trend of body weight growth and in rectal temperature (P <0.05), as well as a slight yet non-significant decrease in spontaneous activity count (P >0.05); compared with the rats in the model group, the rats in the treatment group exhibited a significant increase in rectal temperature (P <0.05) and in spontaneous activity count (P <0.05). Moreover, after 14 days of treatment, compared with the rats in the blank, the rats in the model group exhibited a significant decrease in serum CORT content (P <0.05) and in the expression of 11β-HSD1 in the liver (P <0.05), as well as a slight yet non-significant decrease in serum CRH content (P >0.05); compared with the rats in the model group, the rats in the treatment group exhibited a significant increase in serum CRH content (P <0.05) and in the expression of 11β-HSD1 in the liver (P <0.05), as well as a slight yet non-significant increase in serum CORT content (P >0.05).ConclusionLong-snake moxibustion can increase the rectal temperature and spontaneous activity count of rats with kidney yang deficiency, improve the function of the HPA axis, and increase the expression of 11β-HSD1 in the liver.  相似文献   
4.
横窦是颅内静脉回流重要通路,对维持脑循环及稳定颅内压至关重要。横窦狭窄(TSS)为横窦最常见变异,可致窦腔血流动力学及压力变化,与特发性颅高压、搏动性耳鸣及慢性头痛等密切相关。本文对影像学研究TSS进展进行综述。  相似文献   
5.
神经性厌食症40例临床分析   总被引:2,自引:0,他引:2  
目的探讨神经性厌食症(anorexia nervosa,AN)的临床特点,提高对该病的诊治水平.方法对住院治疗的40例AN患者进行回顾性分析.结果本病青年女性多见(95%),平均年龄20.8±8.4岁.常见诱因为学习或工作压力大(55%),临床上以厌食(100%)、消瘦(100%)、闭经或月经稀发(70%)为主要表现,伴有多种内分泌功能紊乱;57.5%的患者被误诊为甲状腺功能减退症或非溃疡性消化不良等疾病.所有患者入院后均给予心理治疗、促胃肠动力药及营养支持治疗.平均住院21±13d,除1例患者入院3d后自动出院外,其余患者食欲基本恢复正常,体重增加(1~5kg),全身情况改善.结论AN仍是一个被人们认识不足的疾病,临床上应予以重视.  相似文献   
6.
The capitated payment model has been used to address the high cost of health care. Under capitation, physicians are compensated with a fixed amount per patient, regardless of the services generated. We provide new evidence on how the capitation payment model changes physicians behaviors by studying the treatment of lower back pain, as this type of treatment provides substantial scope for physicians discretion. We use data from 2003 to 2006 from a large database of employer-sponsored health insurance claims and leverage capitation variation within the plan and physician to mitigate selection concerns. The results show that the treatment intensity—primarily derived from therapy and diagnostic testing —of patients under a capitation system is 7–12% lower than that of similar patients in a non-capitated plan. Furthermore, we find no evidence of increased relapse rates for patients in a capitated plan.  相似文献   
7.
This paper empirically investigates how competition affects physicians’ opportunistic behavior in the context of the utilization of MRI scanners. We examine micro-panel data on Japanese hospitals, where we observe how physicians change their usage of MRI scanners in response to MRI adoption by nearby hospitals. We identify competition-driven physician-induced demand: Hospitals lose patients because of MRI adoption by nearby hospitals, and, to compensate for this loss, physicians perform more MRI scans per patient. Although competition may benefit consumers through better access to MRI scanners, it also causes additional physician-induced demand.  相似文献   
8.
9.
When consumers gain Medicaid, their cost of healthcare changes. The direction of this change determines how utilization changes. The previously uninsured see a stark decrease in the price of primary care after gaining public insurance. Due to charity care, they may face an increase in the price of emergency department care. The previously insured see a reduction in emergency department prices and decreased access to primary care. We examine the impact of the prior insurance status of the newly publicly insured on substitution between healthcare. We base our identification on California’s LIHP and ACA Medicaid expansions. One challenge we face is estimating crowd-out. We use machine learning techniques to predict prior insurance status based on observable covariates in cross-sectional data. We find an increase in emergency department utilization caused entirely by those crowded-out whose access to primary care has decreased. We find the opposite utilization patterns for the previously uninsured.  相似文献   
10.
《Vaccine》2015,33(30):3480-3487
Our previous study showed that IL-2 and IL-7 could mutually enhance the immunogenicity of canine parvovirus VP2 DNA vaccine, although the underlying mechanism remained unknown. Here, we used the OVA gene as a DNA vaccine in a mouse model to test their enhancement on DNA vaccine immunogenicity and to explore the molecular mechanism. Results showed that both IL-2 and IL-7 genes significantly increased the immunogenicity of OVA DNA vaccine in mice. Co-administration of IL-2 and IL-7 genes with OVA DNA significantly increased OVA-specific antibody titers, T cell proliferation and IFN-γ production compared with IL-2 or IL-7 alone, confirming that IL-2 and IL-7 mutually enhanced DNA vaccine immunogenicity. Mechanistically, we have shown that IL-2 significantly stimulated generation of IL-7 receptor-expressing lymphocytes, and that IL-7 significantly induced IL-2 receptor expression. These results contribute to an explanation of the mechanism of the mutual effects of IL-2 and IL-7 on enhancing DNA vaccine immunogenicity and provided a basis for further investigation on their mutual effects on adjuvant activity and immune regulation.  相似文献   
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