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11.
《Cancer radiothérapie》2020,24(4):306-315
French regulations about research ethics are based on the so-called Jardé law, which defines researches involving human beings. Researches involving human beings require the submission of research protocols to a committee for protection of persons with a precise list of documents to submit for a favourable opinion. This law describes different categories of researches and determines the ethical procedures to apply before setting up a research protocol. This issue of categorisation is central and must be taken into account by researchers from the beginning of the research process. Researches considered as not involving human beings also require a set of ethical precautions focused on patients’ information and the collection of their non-opposition (due to the application of the General Data Protection Regulation adopted by the European Parliament). Thus, many regulations exist and they require a real work for researchers to meet these requirements in research ethics. This article aims to summarise French regulations. Selected examples are specifically taken into the field of radiation oncology research.  相似文献   
12.
Objective: To analyze the effect of sirolimus and sunitinib in blocking the tumor growth and to evaluate the expressions of estrogen receptor (ER), progesterone receptor (PgR), and human epidermal growth factor receptor-2 (HER2/neu) after treated with sirolimus and sunitinib. Methods: Thirty-two female Sprague Dawley rats at age 21-days old were administered intraperitoneally with N-Methyl-N-Nitroso Urea (NMU), dosed at 70mg/kg body weight. The rats were divided into 4 groups; Group 1 (Control, n=8), Group 2 (Sirolimus, n=8), Group 3 (Sunitinib, n=8) and Group 4 (Sirolimus+Sunitinib, n=8), being treated twice when the tumor reached the size of 14.5±0.5 mm and subsequently sacrificed after 5 days. The protein expressions of ER, PgR and HER2/neu of the tumor tissues were evaluated by using immunohistochemistry analysis. Results: Treatment with sirolimus alone lowered expressions of ER and PgR of breast cancer and reduced tumor size. There was no significant difference of ER and PgR expressions between control and sunitinib treated tumor. Sunitinib treated tumors reduce in diameter after the first treatment, however the diameter increases after the second treatment. Histologically, sunitinib treated tumor did not show any aggressive invasive carcinoma of no special type (NST) histological subtypes. In addition, all NMU-induced tumors are HER2/neu-negative scoring. Conclusion: Sirolimus is neither synergistic nor additive with sunitinib for breast cancer treatment.  相似文献   
13.
目的探讨不同转化生长因子-β(TGF-β)表达量的人羊膜间充质干细胞(hAMSCs)尾静脉移植对异种周围神经移植小鼠坐骨神经功能的恢复作用。方法从健康剖宫产产妇志愿捐献的新鲜羊膜中分离出hAMSCs,并进行纯化及鉴定。构建上调和下调TGF-β表达的慢病毒质粒,并转染纯化的hAMSCs,构建出稳定的上调或下调TGF-β表达的hAMSCs。分离并剪去C57BL/6小鼠的部分坐骨神经,将SD大鼠的坐骨神经分离剪取并移植至小鼠的坐骨神经缺损处,构建出异种周围神经移植小鼠模型。将模型小鼠按随机数字表分为对照组、未修饰的hAMSCs治疗组、高表达TGF-β的hAMSCs治疗组、低表达TGF-β的hAMSCs治疗组,每组10只。各组于造模前1 d分别经尾静脉注射磷酸盐缓冲液或相应的hAMSCs重悬液进行移植治疗。于治疗后第14天时采用DigGait步态分析系统评估各组小鼠的坐骨神经功能恢复情况。结果治疗后第14天时,高表达TGF-β的hAMSCs治疗组小鼠的坐骨神经功能指数(-25.820±0.286)明显高于低表达TGF-β的hAMSCs治疗组(-33.413±0.920)和未修饰的hAMSCs治疗组(-30.755±0.421),差异均有统计学意义(P<0.05)。结论高表达TGF-β的hAMSCs尾静脉移植能够更有效地改善异种周围神经移植小鼠的坐骨神经功能,其可能成为周围神经损伤治疗的新突破口。  相似文献   
14.
人间充质干细胞免疫原性研究   总被引:1,自引:0,他引:1  
目的探讨人间充质干细胞(hMSCs)特性及免疫原性,为进一步研究hMSCs移植特性提供实验依据。方法免疫组化方法鉴定hMSCs表面HLA-ABC、HLA-DR、CD80、CD86分子;流式细胞术检测其含量;RT-PCR检测HLA-ABC、HLA-DRmRNA基因片断;外周血淋巴细胞杀伤试验及 CCK-8比色法规察淋巴细胞增殖反应;将表达绿色荧光蛋白(GFP)的DNA复合物导入hMSCs进行大鼠脑内移植,观察hMSCs在脑内的存活情况。结果 hMSCs表面少量表达HLA-ABC分子,不表达 HLA-DR、CD80、CD86分子;有少量HLA-ABC mRNA基因片断存在,未发现HLA-DR mRNA基因片断;外周血淋巴细胞杀伤试验没有发现淋巴细胞增殖反应;大鼠脑内移植hMSCs一个月后仍可见有细胞存活。结论 hMSCs具有较弱的免疫原性。  相似文献   
15.
The aim of this study was to investigate the histological and biological features of the human cerebellar cortex development and differentiation. We analyzed 52 brains of fetal and infant death victims, aged from 17 gestational weeks to 12th postnatal month. In particular, in the cerebellar cortex at different ages we evaluated, besides the structural aspects, the expression of several biomarkers implicated in proliferative processes (c-fos, PCNA and apoptosis). We observed morphological patterns progressively evolving every month, from the indefinite structure of the second gestational trimester to the four-layered structure (external granular layer, molecular layer, Purkinje cell layer, internal granular layer) of the late fetal cortex and subsequently to the three-layered postnatal definitive morphology, due to involution of the external granular layer. The evaluation of the biological features of the cerebellar cortex showed high proliferative activity mainly confined to the transient external granular layer in prenatal life, and high apoptotic index after birth. Thus, the histological examination, better with the support of biomarker investigations, allows with accuracy to describe the dynamic sequence of steps that occur in human cerebellar cortex development and to establish in each case the age, namely the pre- or postnatal month of life. Consequently, we can diagnose delayed or altered processes of differentiation during the development of the human cerebellar cortex.  相似文献   
16.
移植人羊膜细胞对大鼠创伤性脑损伤的实验研究   总被引:6,自引:2,他引:4  
目的 探究大鼠TBI后脑内移植人羊膜细胞(HACs)对大鼠运动功能的影响。方法 HACs经分离、Hoechst33342标记后重悬调整细胞浓度为10^5/μl;采用改进的Feeney自由落体法打击大鼠脑皮层后肢运动区域,损伤后24h经微量注射器和立体定向仪将Hoechst33342标记的HACs 10μl分别移植于挫伤灶中心和挫伤灶边缘;在TBI后的28d内采用钉板平衡木行走测试大鼠运动功能变化,运动功能检测结束后取出脑组织行组织学检测。结果 治疗组滑落脚步数明显少于对照组(P〈0.05);移植的HACs呈蓝色荧光;部分移植HACs可见MAP-2阳性表达。结论 移植HACs使大鼠TBI后运动功能明显改善。  相似文献   
17.
目的探讨人端粒酶催化亚基(hTERT)反义cDNA(pAdeasy-hTERT)在体外对胶质瘤细胞生长的抑制作用。方法将腺病毒介导的pAdeasy-hTERT作用于人胶质瘤细胞系U251,用MTT法检测细胞存活率、端粒酶重复序列扩增法测定端粒酶活性、Westem杂交鉴定hTERT蛋白的表达、RT-PCR法检测hTERT cDNA水平、PCNA观察肿瘤细胞的凋亡情况以及用流式细胞仪对转染后肿瘤细胞的周期进行分析。结果pAdeasy-hTERT在体外明显抑制肿瘤细胞生长,降低端粒酶活性,抑制hTERT表达。结论pAdeasy-hTERT显著抑制人胶质瘤细胞生长,可成为恶性胶质瘤基因治疗的靶基因。  相似文献   
18.
目的:了解广州地区无偿献血者HHV-8的感染情况,为制定预防策略提供依据。方法:采用ELISA法检测3135名无偿献血者血浆HHV-8IgG抗体。结果:3135名献血者中6名血浆标本被检出HHV-8IgG抗体阳性,均为汉族、男性献血员,总阳性率为0.19%。不同年龄和性别组HHV-8感染率差异无统计学意义。结论:广州地区无偿献血人群HHV-8的感染率较低。  相似文献   
19.
国人胚胎肾脏发育的超微结构研究:Ⅰ.肾小体的发育   总被引:1,自引:0,他引:1  
  相似文献   
20.
Summary Cytochemical staining of normal human bone cells in monolayer cultures for alkaline phosphatase (ALP) indicated that the cultures contained mixed-cell populations. Time course evaluations of the cytochemical staining revealed, in addition to the ALP-negative cell population, at least two subpopulations of ALP-positive human bone cells with different levels of ALP. A cytochemical method has been developed which separates the ALP-positive cells into high and intermediate ALP subpopulations. In this method, human bone cells were stained for ALP using an azo-dye method and incubating at 4°C for 10 and 30 minutes, respectively. We defined the cell population that stained positively for ALP at 10 minutes as strong ALP-positive cells, and both strong and intermediate cells were stained at 30 minutes. The intermediate cells were determined from the difference between the values at the two time points. The intra- and interassay variations of the assay, with the same investigator in blinded investigations, were both less than 10% and the interobserver variation was approximately 25%. Analysis of the distribution of ALP levels in cells with a laser densitometer confirmed the presence of at least three cell subpopulations. 1,25(OH)2D3 treatment increased the proportions of both ALP-positive cell populations, whereas TGF-beta treatment increased only the intermediate ALP-positive cell population. On the contrary, fluoride increased the proportion of the strong ALP cells, and IGF-1 had no effect on the proportions of either ALP-positive subpopulation. When the ALP-specific activity was compared with the percentage of each ALP-positive subpopulations for the cells treated with effectors, the ALP-specific activity correlated with the total ALP-positive and with the strong ALP-positive populations but not with the intermediate ALP-positive subpopulation. In summary, this study represents the first evidence that normal human bone cells in monolayer cultures contained at least two subpopulations of ALP-positive cells, and that bone cell effectors could have differential effects on each cell population.  相似文献   
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