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61.
Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system. Exogenous cell replacement in MS lesions has been proposed as a means of achieving remyelination when endogenous remyelination has failed. However, the ability of exogenous cells to remyelinate axons in the presence of inflammation remains uncertain. We have explored the remyelinating capacity of an oligodendrocyte progenitor cell line CG-4 transduced with the GFP gene and transplanted adjacent to a zymosan-induced focal demyelination model in the rat spinal cord. The resulting zymosan-induced lesions were characterized by persistent macrophage/microglia activation, focal demyelination, degeneration of axons, and reactive astrogliosis. GFP(+) CG-4 cells were found to migrate preferentially toward the inflammatory lesion and survive inside the lesion. A proportion of GFP(+) CG-4 cells differentiated into mature oligodendrocytes and remyelinated axons within the lesion. These findings suggest that grafted oligodendrocyte progenitors may migrate toward areas of inflammation in the adult rat spinal cord, where they can survive and differentiate into myelinating oligodendrocytes.  相似文献   
62.
目的 了解我院神经外科介入治疗病人的院内感染现况,分析感染相关的危险因素,为控制神经介入治疗后院内感染与制定预防措施提供参考。方法 回顾性分析2016年1~12月我院神经外科介入治疗的1274例病人的临床资料,统计院内感染率,并对引发院内感染的相关因素进行统计学分析。结果 神经外科介入治疗后院内感染率为2.47%,感染类型主要为呼吸系统感染(72.5%),其次为血液系统感染(15.0%)、泌尿系统感染(7.5%)、中枢神经系统感染(5.0%)。多因素logistic回归分析显示低白蛋白血症、低钾血症、术后输血、留置静脉置管是神经外科介入治疗后院内感染的独立危险因素(P<0.05)。结论 多种因素与神经外科介入治疗院内感染密切相关,应进行针对性地预防,从而达到减少院内感染的目的  相似文献   
63.

Background

Urinary cell-free DNA (ucfDNA) has great potential as a “liquid biopsy” for use in diagnosis of urological cancers. In this study, we compared ucfDNA gene expression levels between patients with bladder cancer (BC) and those with hematuria, and determined whether they could be used as a noninvasive urine-based marker.

Methods

The study cohort of 355 patients included a screening group (40 BC and 41 hematuria controls) and a validation cohort (149 BC and 125 hematuria controls). Expression levels ratios of 1 up-regulated gene (IQGAP3) to those of 7 down-regulated genes were examined in ucfDNA in the screening group to identify ratios that differed significantly between BC and hematuria patients. IQGAP3/BMP4 and IQGAP3/FAM107A ratios were selected and combined to develop a discriminant score (DS) index, which was tested in the validation cohort. Receiver operating characteristic curves and areas under the curve were calculated to evaluate the performance of the DS index.

Results

IQGAP3/BMP4 and IQGAP3/FAM107A ratios in ucfDNA were both significantly higher in BC patients than in hematuria patients (both P < 0.001). The DS index had an area under the curve of 0.862, a sensitivity of 71.0%, a specificity of 88.6%, a positive predictive value of 90.3%, and a negative predictive value of 67.2%.

Conclusions

Both IQGAP3/BMP4 and IQGAP3/FAM107A ratios in ucfDNA were significantly higher in patients with BC than in those with hematuria. The DS index exhibits good diagnostic performance as a noninvasive biomarker.  相似文献   
64.

Background

Previous studies showed that early after Roux-en-Y gastric bypass (RYGB), there is a remarkable improvement in type 2 diabetes, which is characterized by insulin resistance. This study aims to gain insight into the underlying mechanisms of this effect. We determined the acute effects of RYGB on hepatic and peripheral insulin sensitivity.

Methods

A rat model of type 2 diabetes was established using high-fat diet combined with streptozotocin (30 mg/kg, ip). Animals were divided into four groups: diabetic, diabetic RYGB, diabetic RYGB sham, and control rats. Hyperinsulinemic-euglycemic clamps with tracer infusion were completed at 2 weeks postoperatively to assess insulin sensitivity. Triglyceride concentration in liver and muscle tissues was determined. Protein kinase C (PKC) membrane translocation, protein expression of phospho-c-Jun NH2-terminal kinase (JNK), and phospho-IκB kinase β (IKKβ) were assessed with western blot. Malondialdehyde (MDA) and superoxide dismutase (SOD) activities in the liver were also measured.

Results

RYGB surgery significantly improved hepatic insulin sensitivity index and decreased hepatic triglyceride concentration (P?<?0.05), without an improvement in peripheral insulin sensitivity. Membrane translocation of PKC-ε, PKC-δ, and PKC-θ; the ratio of MDA to SOD; and the expression of p-JNK and p-IKKβ in the liver were lower in the diabetic RYGB group than in the diabetic group.

Conclusions

Diabetes remission was induced at short term after RYGB. The improvement of hepatic tissue lipotoxicity decreased the activation of certain PKC isoforms, the activity of JNK and IKK inflammatory signaling pathways, and the degree of oxidative stress. Furthermore, the hepatic insulin sensitivity was ameliorated, which is possibly a mechanism for early diabetes remission.  相似文献   
65.
目的建立小鼠免疫耐受模型,探讨单倍体异基因淋巴细胞输注在小鼠移植物抗宿主病(GVHD)和移植物抗肿瘤(GVT)效应中的意义。方法64只BALB/C雌性小鼠按随机数字表法分为4组,每组16只。对照组:实验第4天接种肿瘤细胞(小鼠大肠癌CT26细胞株配制成1×10^7/mL的瘤细胞悬液,接种到雌性小鼠右腋皮下)后不予任何特殊处理;化疗组:实验第4天接种肿瘤细胞,第7天开始化疗;供体淋巴细胞输注(DLI)组:实验开始时进行预处理,第4天接种肿瘤细胞,第13、15、17天输注单倍体异基因淋巴细胞(雄性BALB/C小鼠制备的脾淋巴细胞);化疗+DLI组:实验开始时进行预处理,第4天接种肿瘤细胞,第7天开始化疗,第13、15、17天输注单倍体异基因淋巴细胞。预处理方案为输注单倍体异基因淋巴细胞+环磷酰胺+输注单倍体异基因淋巴细胞。化疗方案为小鼠接种肿瘤细胞后第3天给予环磷酰胺腹腔化疗。每日观察各组小鼠临床GVHD的指标,并给予临床评分。观察荷瘤鼠肿瘤生长情况,计算接种成功后首日到小鼠死亡的时间和肿瘤质量,计算抑瘤率。应用流式细胞仪检测各组小鼠外周静脉血中T细胞数量,接种后15d各组处死3只小鼠取瘤体制作成观察切片,HE染色后光镜观察。多组比较采用方差分析,组间比较采用LSD—t检验。结果化疗+DLI组的小鼠GVHD临床表现轻于其他组小鼠。对照组、化疗组、DLI组、化疗+DLI组GVHD评分分别为(2.3±0.6)分、(1.5±1.1)分、(6.7±0.9)分、(3.4±0.5)分,4组比较,差异有统计学意义(F=148.68,P〈0.05)。4组小鼠全部接种CT26细胞成功。对照组、化疗组、DLI组、化疗+DLI组小鼠肿瘤质量分别为(3.40±0.20)g、(0.80±0.10)g、(2.20±0.20)g、(0.50±0.30)g,4组比较,差异有统计学意义(F=149.17,P〈0.05);4组小鼠抑瘤率分别为0、77%±9%、35%±3%、85%±44%;4组小鼠CD3’分别为52.3%±2.9%、44.8%±3.1%、62.9%±3.5%、65.9%±3.3%,4组比较,差异有统计学意义(F:28.04,P〈0.05);4组小鼠CD3+CD4+分别为32.1%±2.6%、27.1%±1.1%、42.6%±1.8%、41.7%±2.4%,4组比较,差异有统计学意义(F=40.29,P〈0.05);4组小鼠CD3+CD8+分别为22.7%±2.2%、20.7%±1.8%、26.7%±0.8%、26.1%±0.7%,4组比较,差异有统计学意义(F=10.74,P〈0.05);4组小鼠CD3+CD+CD25+分别为8.7%±0.6%、6.6%±0.6%、11.2%±0.4%、13.3%±0.7%,4组比较,差异有统计学意义(F=82.88,P〈0.05)。4组小鼠的肿瘤组织均有不同程度的坏死、出血,其中DLI组和化疗+DLI组肿瘤组织大片坏死,瘤细胞变小,间质内有大量炎性细胞浸润,化疗+DLI组还可见大量增生的淋巴滤泡。对照组、化疗组、DLI组、化疗+DLI组小鼠生存时间分别为(16.8±2.5)d、(26.3±2.9)d、(23.4±2.5)d、(33.7±4.6)d,4组比较,差异有统计学意义(F=46.45,P〈0.05)。结论(1)预处理方案可以诱导小鼠的特异性免疫耐受。(2)单倍体异基因淋巴细胞输注与化疗具有协同作用,联合应用可以抑制小鼠皮下移植瘤瘤体的生长以及延长小鼠的生存时间。(3)化疗可降低供体淋巴细胞输注后诱发的GVHD效应并且提高了GVT效果。(4)CD3+CIN+CD25+T淋巴细胞在降低GVHD反应中起着重要的作用。  相似文献   
66.
67.
Epidemiological studies have shown that inhalation of radonis associated with an increased risk for bronchogenic carcinomain uranium miners. These  相似文献   
68.
20例脑肿瘤术中应用B超定位切除的意义   总被引:5,自引:0,他引:5  
目的:总结术中B超在脑肿瘤手术中的意义方法:对20例脑肿瘤患者26个病灶实施术中B超脑肿瘤切除结果:20例患者26个病灶行术中B超定位脑肿瘤切除,肿瘤定位准确,不需探查,肿瘤切除满意,无脑组织损伤.未出现相应明显的神经系统障碍结论:术中B超操作简便,重复性强,定位准确,安全经济,肿瘤切除满意,具有广泛的应用前案  相似文献   
69.
杨迎暴  朴英杰 《中药材》2002,25(12):882-885
目的:探讨白藜芦酶(resveratrol,Res)对脊髓损伤(SCI)后受损部位局部Ca^2 ,Mg^2 -ATP酶活性的影响,分析SCI后局部部微环境改变及Res的作用。方法:采用重物下落撞击法制备成年大鼠的脊髓损伤,于损伤后即刻腹腔注射给于Res50mg/kg,100mg/kg或甲基强的松龙(MPSS)100mg/kg,并于给药后1h,24h,48h时分别取受损脊髓,利用测磷法检测Ca^2 ,Mg^2 -ATP酶活性。结果:Res100mg/kg对Ca^2 -ATP,Mg^2 -ATP及Ca^2 ,Mg^2 -ATP酶活性在SCI后的活性抑制有明显的改善作用(P<0.05或0.003),最大改善率分别在71%,180%和120%以上,基本以1h时影响较大,但对Mg^2 -ATP酶活性的最大影响在48h时,MPSS对SCI后1hCa^2 Mg^2 -ATP酶活性影响最大。Res的作用与MPSS相当或更强。结论:Res通过调节Ca^2 Mg^2 -ATP酶活性改善SCI后局部微环境,可能有效缓解SCI后继发性反应而产生保护作用。  相似文献   
70.
The neuroanatomical distribution of androgen receptor (AR) mRNA-containing cells in the brain of a vocal lizard, Gekko gecko, was mapped using in situ hybridization. Particular attention was given to auditory and vocal nuclei. Within the auditory system, the cochlear nuclei, the central nucleus of the torus semicircularis, the nucleus medialis, and the medial region of the dorsal ventricular ridge contained moderate numbers of labeled neurons. Neurons labeled with the AR probe were located in many nuclei related to vocalization. Within the hindbrain, the mesencephalic nucleus of the trigeminal nerve, the vagal part of the nucleus ambiguus, and the dosal motor nucleus of the vagus nerve contained many neurons that exhibited strong expression of AR mRNA. Neurons located in the peripheral nucleus of the torus in the mesencephalon exhibited moderate levels of hybridization. Intense AR mRNA expression was also observed in neurons within two other areas that may be involved in vocalization, the medial preoptic area and the hypoglossal nucleus. The strongest mRNA signals identified in this study were found in cells of the pallium, hypothalamus, and inferior nucleus of the raphe. The expression patterns of AR mRNA in the auditory and vocal control nuclei of G. gecko suggest that neurons involved in acoustic communication in this species, and perhaps related species, are susceptible to regulation by androgens during the breeding season. The significance of these results for understanding the evolution of reptilian vocal communication is discussed.  相似文献   
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