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91.
The most common cause of Pelizaeus‐Merzbacher (PMD) is due to duplication of the PLP1 gene but it is unclear how increased gene dosage affects PLP turnover and causes dysmyelination. We have studied the dynamics of PLP/DM20 in a transgenic mouse model of PMD with increased gene dosage of the proteolipid protein gene (Plp1). The turnover of PLP/DM20 were investigated using an ex‐vivo brain slice system and cultured oligodendrocytes. Homozygous mice have reduced PLP translation, markedly enhanced PLP degradation, and markedly reduced incorporation of PLP into myelin. Proteasome inhibition (MG132) prevented the enhanced degradation. Numerous autophagic vesicles are present in homozygous transgenic mice that may influence protein dynamics. Surprisingly, promoting autophagy with rapamycin decreases the degradation of nascent PLP suggesting autophagic vacuoles serve as a cellular storage compartment. We suggest that there are multiple subcellular fates of PLP/DM20 when overexpressed: the vast majority being degraded by the proteasome, a proportion sequestered into autophagic vacuoles, probably fused with endolysosomes, and only a small proportion entering the myelin sheath, where its association with lipid rafts is perturbed. Transgenic oligodendrocytes have fewer membrane sheets and this phenotype is improved with siRNA‐mediated knockdown of PLP expression that promotes the formation of MBP+ myelin‐like sheets. This finding suggests that RNAi technology is in principle applicable to improve CNS myelination when compromised by PLP/DM20 overexpression. © 2010 Wiley‐Liss, Inc.  相似文献   
92.
Analysis of the apparent diffusion coefficient (ADC) maps derived from diffusion-weighted MR imaging is emerging as a reproducible, sensitive, and quantitative tool to evaluate brain damage in diseases of the white and gray matter. To explore the potentials of ADC maps analysis in degenerative ataxias, we examined 28 patients and 26 age-matched controls with T1, T2, and diffusion (b values 0-1000 along the three main body axes)-weighted MR images. Twenty-four patients had inherited genetically proven diseases including spinocerebellar ataxia type 1 (SCA1) (n = 9), spinocerebellar ataxia type 2 (SCA2) (n = 8), and Friedreich's ataxia (FA) (n = 7), whereas four patients had sporadic adult onset pure cerebellar ataxia (three idiopathic, one gluten intolerance). Area and linear measurements of the CNS structures contained in the posterior cranial fossa (PCF) preliminary enabled classification of the patients in the three morphological categories reflecting the gross pathology findings, namely olivopontocerebellar atrophy (OPCA) (n = 10: six SCA2 and four SCA1), spinal atrophy (SA) (n = 7: all FA), and cortical cerebellar atrophy (CCA) (n = 4: three idiopathic and one gluten intolerance). Seven patients with SCA1 (n = 5) or SCA2 (n = 2) had morphologic changes reminiscent of OPCA, but their values were still in the lower normal range and were classified as undefined. Mean diffusivity (D) maps of the entire brain were generated and D was measured with regions of interest (ROI) in the medulla, pons, middle cerebellar peduncles, and the peridentate white matter. Moreover, after exclusion of the skull with manual segmentation and of the CSF with application of a threshold value, histograms were obtained for D of the brainstem and cerebellum and for D of the cerebral hemispheres. As compared to controls, a (P < 0.001) increase of D was observed in the medulla, middle cerebellar peduncles, and peridentate white matter in OPCA and undefined patients groups who had also significantly increased values of the 25th and 50th percentiles in the brainstem and cerebellum D histogram. In CCA (P = 0.01), an increase of the 25th and 50th percentile of the D value was observed in the brainstem and cerebellum histograms. The SA group showed (P < 0.001) an increased D in the medulla only. A correlation between clinical severity as assessed with the Inherited Ataxias Clinical Rating Scale (IACRS) and the 50th percentile of the D value in the brainstem and cerebellum histogram (r = 0.69) was observed in patients with SCA1 or SCA2. Diffusion MR imaging reveals variable patterns of increase of D in the brainstem, cerebellum, and cerebral hemispheres in degenerative ataxias that match the known distribution of the neuropathological changes.  相似文献   
93.
A model of corrective gene transfer in X-linked ichthyosis   总被引:5,自引:0,他引:5  
Single gene recessive genetic skin disorders offer attractive prototypes for the development of therapeutic cutaneous gene delivery. We have utilized X-linked ichthyosis (XLI), characterized by loss of function of the steroid sulfatase arylsulfatase C (STS), to develop a model of corrective gene delivery to human skin in vivo. A new retroviral expression vector was produced and utilized to effect STS gene transfer to primary keratinocytes from XLI patients. Transduction was associated with restoration of full-length STS protein expression as well as steroid sulfatase enzymatic activity in proportion to the number of proviral integrations in XLI cells. Transduced and uncorrected XLI keratinocytes, along with normal controls, were then grafted onto immunodeficient mice to regenerate full thickness human epidermis. Unmodified XLI keratinocytes regenerated a hyperkeratotic epidermis lacking STS expression with defective skin barrier function, effectively recapitulating the human disease in vivo. Transduced XLI keratinocytes from the same patients, however, regenerated epidermis histologically indistinguishable from that formed by keratinocytes from patients with normal skin. Transduced XLI epidermis demonstrated STS expression in vivo by immunostaining as well as a normalization of histologic appearance at 5 weeks post-grafting. In addition, transduced XLI epidermis demonstrated a return of barrier function parameters to normal. These findings demonstrate corrective gene delivery in human XLI patient skin tissue at both molecular and functional levels and provide a model of human cutaneous gene therapy.   相似文献   
94.
95.
目的;探讨手术治疗胸椎结核的更好方法。方法;自1990年以来,对21例胸椎结核导致椎柱不稳的患者,应用病灶清除,哈氏棒内固定,椎间及椎板植骨的手术方法。本组平均33.2岁。胸7椎体6例,胸8椎体8例,胸10椎体7例,椎体压缩〈1/2椎体高度13例,〉1/2椎体高度8例,并不全瘫14例。手术中先行病灶清除,然后哈氏棒内固一,撑开后再次清除病灶,取肋骨和髂骨行椎间及椎板上植骨。术后化疗12~15月。结  相似文献   
96.
目的 应用网络药理学分析金藤清痹颗粒治疗急性痛风性关节炎(acute gouty arthritis,AGA)的作用机制,并建立AGA大鼠模型进行验证。方法 在清热解毒、活血止痛治法指导下,通过TCMSP数据库搜集金藤清痹颗粒的活性成分及靶点,利用GeneCards、NCBI数据库等搜集AGA相关靶点,与金藤清痹颗粒作用靶点整合后,构建共有靶点蛋白质-蛋白质相互作用(protein-protein interaction,PPI)网络和“金藤清痹颗粒-中药-活性成分-靶点-AGA”网络,并进行基因本体(gene ontology,GO)功能及京都基因与基因组百科全书(Kyoto encyclopedia of genes and genomes,KEGG)通路富集分析。雄性SD大鼠随机分为空白组、模型组、秋水仙碱(0.3 mg/kg)组和金藤清痹颗粒低、中、高剂量(1.05、2.10、4.20 g/kg)组,每组6只,踝关节注射单钠尿酸盐(monosodium urate,MSU)晶体建立AGA大鼠模型。采用游标卡尺测量大鼠踝关节直径,计算踝关节肿胀度;采用全自动生化仪检测血清尿酸(serum uric acid,SUA)、C反应蛋白(C-reactive protein,CRP)水平;采用苏木素-伊红(HE)染色观察踝关节组织病理变化;采用qRT-PCR、ELISA和Western blotting检测踝关节组织及血清中关键靶点和信号通路的表达。结果 共检索到金藤清痹颗粒110种活性成分、212个作用靶点,272个AGA治疗靶点,共有靶点29个,关键靶点有白细胞介素-1β(interleukin-1β,IL-1β)、肿瘤坏死因子(tumor necrosis factor,TNF)及IL-6,涉及TNF信号通路、IL-17信号通路和NOD样受体信号通路等。大鼠踝关节注射MSU晶体后明显肿胀(P<0.01),SUA及CRP显著升高(P<0.05、0.01),滑膜组织增生明显、结构紊乱,有大量炎症细胞浸润,NOD样受体热蛋白结构域相关蛋白3(NOD-like receptor thermal protein domain associated protein 3,NLRP3)、NIMA相关蛋白激酶7(NIMA-related kinases 7,NEK7)、凋亡相关斑点样蛋白(apoptosis-associated speck-like protein containing a CARD,ASC)、半胱氨酸天冬氨酸蛋白酶-1(cystein-asparate protease-1,Caspase-1)、消皮素D(gasdermin D,GSDMD)、IL-18、IL-1β、IL-6及TNF-α表达水平明显升高(P<0.01);秋水仙碱或金藤清痹颗粒治疗后,有效缓解踝关节肿胀(P<0.05、0.01),SUA及CRP均显著降低(P<0.05、0.01),关节滑膜增生、炎症细胞浸润均得到改善,同时显著抑制IL-1β、TNF-α及IL-6等靶点和NOD样受体信号通路的表达(P<0.05、0.01)。结论 金藤清痹颗粒对AGA大鼠具有明显的保护作用,其机制可能与抑制NOD样受体信号通路的异常激活,降低炎症因子水平,改善关节滑膜增生、炎症细胞浸润有关。  相似文献   
97.
98.
The effect of subcutaneous levonorgestrel implants on reproduction in female tammar wallabies was investigated during the breeding and non-breeding season. Female tammars were given either a control or a levonorgestrel implant and their pouch young were removed to terminate embryonic diapause. Both the control and the levonorgestrel-implant animals treated during the months of May and June gave birth, demonstrating that levonorgestrel does not prevent the reactivation of the diapausing blastocyst or its subsequent development when given at these times. However, none of the levonorgestrel-treated animals mated post partum, whereas all of the control females that gave birth had a post partum oestrus and mated. Control animals gave birth again when the neonate was removed, and continued to breed normally during the following 36 months of the investigation. None of the levonorgestrel-treated animals gave birth again or mated during the next 36 months. Animals given control implants during December did not reactivate or give birth until the normal start of the breeding season in late January. Animals treated with levonorgestrel implants during December did not reactivate with the control animals at the beginning of the breeding season and did not give birth during the next 36 months. There were no effects of levonorgestrel treatment on early lactation. Levonorgestrel implants were removed from six females and four of these animals resumed reproductive activity, confirming that the contraceptive effect of the implants is reversible. Levonorgestrel implants therefore provide a highly effective, reversible and long-term method of contraception for tammar wallabies. This contraceptive system appears to offer a method of population control for the management of overabundant captive and selected wild populations of macropodid marsupials.  相似文献   
99.
摘要:目的 探讨新疆乌鲁木齐市维吾尔族人群成人支气管哮喘的影响因素。方法 本研究采用成组匹配病例对照研究方法,病例组为新疆医科大学第一附属医院呼吸内科在2014年1-12月确诊的维吾尔族支气管哮喘成人患者(n=120例),对照组为同期体检中心健康维吾尔族体检者(n=126例),两组在年龄、性别相匹配。采用问卷调查的方法收集相关暴露资料,并采用单因素分析及多因素非条件Logistic回归模型分析成人支气管哮喘影响因素。结果 多因素Logistic回归分析显示,吸烟(OR=1.88,95% CI:1.28~2.96)、家族支气管哮喘史(OR=6.20,95% CI:2.10~18.31)、家中铺有纯毛地毯数量多(OR=1.87,95% CI:1.18~2.95),睡眠质量(OR=1.46,95% CI:1.22~1.75),患慢性支气管炎(OR=13.43,95% CI:6.65~25.34)及过敏性鼻炎(OR=6.27,95% CI:3.63~10.81)是维吾尔族成人支气管哮喘的主要影响因素。结论 维吾尔族成人支气管哮喘是生活方式、环境及遗传等多种因素共同作用的结果,应加强对相关影响因素的预防及治疗,减少哮喘的发生,改善哮喘患者生活质量。  相似文献   
100.
目的探讨后路椎间盘镜下腰椎间盘摘除术(MED)及传统开放腰椎间盘摘除术对腰椎生物力学稳定性的影响。方法选用6具新鲜尸体脊柱标本,模拟后路腰椎间盘摘除的不同术式,依次对标本腰3~4间隙进行处理,共设计5种减压情况:MED、半椎板切除、半椎板切除并下关节突1/2切除、半椎板切除并下关节突全部切除和全椎板切除髓核摘除术。在力学实验机上分别对实验标本进行前屈/后伸、左/右侧屈及左/右轴向旋转运动,测量不同运动的最大范围。结果模拟MED手术脊柱标本向各个方向的运动与正常对照组比较差异无统计学意义(P>0.05);半椎板切除术、半椎板切除并下关节突1/2切除后,标本向各个方向的运动除半椎板切除并下关节突1/2切除后右侧旋转外与正常对照组差异无统计学意义(P>0.05),半椎板切除并下关节突全部切除后,标本向各个方向运动与正常对照组比较差异均有统计学意义(P<0.05,右侧旋转P<0.01);模拟全椎板切除标本向各个方向的运动与正常对照组比较差异均有统计学意义(P<0.01)。结论MED手术对脊柱破坏性较小,对稳定性无影响,而半椎板并小关节切除则破坏了稳定性。  相似文献   
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