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1.
【目的】构建小鼠高迁移率族蛋白B1(high-mobility group box 1 protein,HMGB1)启动子全长序列的荧光素酶报告基因用于药物筛选。【方法】采用PCR技术扩增小鼠HMGB1基因启动子全长序列,用GV238载体构建报告质粒GV238-HMGB1-P-Luc,以pGL3-basic作为阴性对照质粒,与内参质粒pRL共转染Hela细胞,以内毒素(LPS,0.2μg/mL)作为激活剂,以正丁酸钠(SB,10 mmol/L)作为抑制剂,分组处理24 h后检测荧光素酶活性。【结果】经酶切、PCR及测序鉴定证实克隆的HMGB1基因启动子全长2 140 bp,DNA序列正确无突变。与pGL3-basic组比较,GV238-HMGB1-P-Luc组荧光素酶活性显著增强(P0.05);与GV238-HMGB1-P-Luc组比较,LPS组荧光素酶活性显著增强(P0.01);与LPS组比较,SB组荧光素酶活性显著降低(P0.01)。【结论】HMGB1基因启动子报告基因构建成功,LPS可以增强其表达,SB则可以抑制LPS刺激下的HMGB1启动子表达增强,可为下一步筛选具有调控HMGB1启动子活性的药物奠定基础。  相似文献   
2.
Objective: It is not known whether autonomic neuropathy is a feature of Sjögren’s syndrome (SS) or whether it is related to circulating antiganglionic acetylcholine receptor (gAChR) antibodies. The goal of the present study was to investigate the autonomic dysfunction in patients with SS and the associations between autonomic dysfunction, anti-gAChR antibodies, and clinical features of SS.

Methods: (1) The first observational study tested for the presence of gAChR antibodies in the serum samples from 39 patients with SS (absent information regarding autonomic symptoms) and healthy volunteers. (2) In the second study, serological and clinical data from 10 Japanese patients diagnosed with SS were reviewed. These patients showed autonomic dysfunction, and luciferase immunoprecipitation systems (LIPS) test was conducted to detect anti-α3 and anti-β4 gAChR antibodies. (3) In the final analysis, we combined the data of seropositive SS patients with autonomic symptom from the first study with all of the patients from the second study, and analyzed the clinical features.

Results: (1) The LIPS assay revealed that anti-gAChRα3 and anti-gAChRβ4 antibodies were detected in the sera from patients with SS (23.1%, 9/39). Five of nine SS patients had autonomic symptoms. (2) Anti-α3 and anti-β4 gAChR antibodies were also detected in 80.0% (8/10) of patients with SS with autonomic symptoms. Six of the ten patients were diagnosed as having SS after neurological symptoms developed. These seropositive patients had predominant and severe autonomic symptoms and were diagnosed with autonomic neuropathy. (3) Thirteen of fifteen SS patients with autonomic symptoms (86.7%) were seropositive for anti-gAChR antibodies, and we confirmed sicca complex, orthostatic hypotension, upper and lower gastrointestinal (GI) symptoms, and bladder dysfunction at high rates.

Conclusion: The present results suggest the possibility of anti-gAChR antibodies aiding the diagnostics of SS with autonomic dysfunction.  相似文献   
3.
目的 建立人源性雌激素受体(hERα/β)介导的荧光素酶报告基因试验方法,比较不同雌激素受体亚型介导的报告基因试验的反应性和灵敏度,为检测内分泌干扰物拟雌激素活性提供研究工具。方法 以恒河猴肾细胞(LLC-MK2)为转染细胞,以萤火虫荧光素酶基因(Luc)为报告基因,利用瞬时转染的方法,将表达hERα/hERβ的质粒与重组Luc报告基因质粒pERE-minP-Luc2P、内对照质粒pGL4.74共转染LLC-MK2细胞,建立由hERα/β介导的Luc报告基因试验方法。以雌二醇(E 2)、己烯雌酚(DES)作为阳性受试物,以10-5 mol/L 雌激素拮抗剂(ICI 182,780)和不同浓度的E 2共同染毒,观察Luc表达的变化。用双酚A(BPA)和染料木黄酮(GS)对方法的有效性进行检验并比较雌激素受体两亚型反应性、灵敏度和特异性。结果 hERα报告基因系统对E 2的最低检测限为1.9×10-11 mol/L,在10-8 mol/L处获得最高诱导倍数,是对照组的30.7倍。hERβ报告基因系统对E 2的最低检测限为2.2×10-11 mol/L,在10-8 mol/L处获得最高诱导倍数,是对照组的14.4倍。ICI 182,780在10-5 mol/L浓度下能显著抑制两个报告基因系统E 2的雌激素活性。未转染受体表达载体hER-pcDNA3.1的LLC-MK2细胞用不同浓度E 2诱导,两个报告基因系统均与E 2无明显反应。BPA和GS在以上两个不同的报告基因系统中均能诱导Luc表达,但同一受试物在不同雌激素亚型介导的报告基因系统中表达倍数不同。结论 本研究建立ER不同亚型的报告基因试验有较高的灵敏度和重复性。hERα介导的报告基因试验灵敏度高于hERβ,在hERα系统中BPA雌激素活性强于GS,在hERβ系统中GS雌激素活性强于BPA。  相似文献   
4.
目的 探讨SETD4(SET-domain containing protein 4)对脂多糖(LPS)诱导的AML12(小鼠肝脏细胞系)细胞IL-6的转录调控作用。 方法 构建SETD4表达质粒和IL-6 启动子荧光素酶报告基因质粒,共转染小鼠肝脏细胞系AML12,使用双荧光素酶报告基因技术检测LPS刺激后IL-6 启动子荧光素酶活性;单独转染SETD4表达质粒上调AML12细胞SETD4表达,检测LPS刺激后IL-6 mRNA水平变化。 结果 双酶切鉴定及核酸测序证实重组质粒pcDNA3.0/HA-SETD4、pGL3.0/IL-6 promoter的构建成功。pcDNA3.0/HA-SETD4与pGL3.0/IL-6 promoter共转染AML12细胞,LPS刺激后SETD4对IL-6 启动子荧光素酶活性没有影响;上调SETD4表达后,可以促进LPS诱导的IL-6 mRNA转录。 结论 成功构建SETD4真核表达质粒和IL-6启动子荧光素酶报告基因质粒;SETD4对LPS诱导的AML12细胞IL-6的转录发挥正调控作用。  相似文献   
5.
6.
目的 探讨利用含HSPA1A(HSP70-1)启动子荧光素酶报告基因质粒的稳定转染HepG2/HSPA1A细胞评价焦炉逸散物毒性的可行性.方法 构建含HSPA1A启动子的pGL4.17/HSPA1A重组质粒并转染人HepG2细胞,建立稳定细胞株HepG2/HSPA1A.用不同浓度的炉底、炉侧和炉顶焦炉逸散物染毒HepG2/HSPA 1A细胞24h,分别测定细胞的相对荧光素酶活力、存活率、丙二醛(MDA)含量、Olive尾距和微核率.结果 与对照组相比,炉底焦炉逸散物染毒组细胞的相对荧光素酶活力明显升高,差异有统计学意义(P<0.01).且在0.15 μg/L时,细胞的相对荧光素酶活力最高,为对照组的1.4倍.细胞的相对荧光素酶活力分别随着炉侧和炉顶焦炉逸散物浓度的增加而逐渐增加,差异均有统计学意义(P<0.01).且在最高浓度时(65.4 μg/L,202 μg/L)细胞的相对荧光素酶活力分别为对照组的2.1和5.3倍.仅炉底焦炉逸散物染毒后细胞的相对荧光素酶活力与MDA浓度呈正相关,差异有统计学意义(r=0.404,P<0.05).炉底、炉侧和炉顶焦炉逸散物染毒后,HepG2/HSPA1A细胞的相对荧光素酶活力均与Olive尾距、微核率呈正相关(r尾距分别为0.476、0.940、0.788,r微核率分别为0.580、0.649、0.432),P<0.05.结论 HepG2/HSPA1A细胞的相对荧光素酶活力可以敏感地反映焦炉逸散物的毒性效应,该细胞可用于快速评估职业环境复合污染物的综合毒性效应.  相似文献   
7.
8.
Layer-by-layer assembled microcapsules have the potential to be versatile cell delivery systems incorporating multiple activities and functions. However, it is necessary to determine the influence that different capsule locations have on activity of bioactive molecules in order to optimise delivery and for generation of multifunctional capsules. In this study we examine the influence that locating the bioluminescent enzyme luciferase in different microcapsule locations has on activity in intact synthetic and biodegradable microcapsules before and after cell delivery as well as its susceptibility to protease degradation. We also examine the effect of microcapsule position on cell transfection with plasmid DNA. Based on the findings of experiments in this study we also demonstrate co-delivery of luciferase protein and plasmid DNA encoding a fluorescent protein from two different locations within the same microcapsule. Our studies confirm that, the core, subouter layer, and outer layer are optimal for cell delivery but these positions offer least protection from protease activity. By contrast middle layer molecules remain entangled with capsule layers preventing their release which is inefficient for cell delivery but this provides better protection from protease degradation. The findings of this study will enable more rationale layer-by-layer assembly of microcapsules containing biologically active molecules for cell delivery and aid in the generation of multifunctional microcapsules.  相似文献   
9.

Background

Bioluminescence imaging (BLI) is an ideal tool for noninvasive, quantitative monitoring of tumor progression/regression in animal models. The effectiveness of different treatment strategies is displayed by an altered intensity of bioluminescence, demonstrating a change of the tumor burden. The aim of this study was to establish a reliable, reproducible colorectal hepatic metastases cancer animal model.

Methods

Cells of the human colon carcinoma cell line HCT-116 Lucpos expressing the firefly luciferase enzyme gene were used. HCT-116 Lucpos cells (2.5 × 106) were injected through the portal vein into the liver of immunoincompetent nude mice. BLI was used to analyze intrahepatic tumor burden and growth kinetic.

Results

HCT-116 Lucpos cells demonstrated a progressive and reproducible growth in the liver after intraportal injection. Four days after injection, the animals were analyzed for tumor growth by BLI, and mice without or too low bioluminescence signals were excluded (between 10% and 20% animals). HCT-116 Lucpos intrahepatic tumors responded successfully to different dosages (5 and 10 mg/kg) of 5-fluorouracil.

Conclusions

BLI is an important tool with many potential advantages for investigators. The measurement of intrahepatic tumor growth by imaging luciferase activity noninvasively provides valuable information on tumor burden and effectiveness of therapy. Thus, the presented intrahepatic metastases model based on the growth of HCT-116 Lucpos cells is suitable for in vivo testing of different cancer therapy strategies.  相似文献   
10.
目的 确定Prss37基因的转录起始位点,并利用转基因技术在整体水平验证该启动子的组织特异性.方法 运用cDNA 5'末端快速扩增法(5' RACE)对C57BL/6J小鼠睾丸mRNA进行分析,确定Prss37的转录起始位点;构建Prss37内源启动子区域转录起始位点上游不同长度DNA片段(1 kb、2 kb、4 kb)驱动的荧光素酶基因表达的质粒;通过受精卵雄原核显微注射技术获得上述三种启动子驱动荧光素酶基因表达的转基因小鼠;利用活体成像技术观察荧光素酶基因的表达,明确启动子的组织特异性.结果 Prss37基因的转录起始位点位于NCBI GeneBankTM(NM_026317.2)报道序列上游的40 bp处;成功获得三种转基因小鼠,其中1kb启动子驱动的转基因小鼠检测到荧光素酶基因的表达,且在脑、睾丸和附睾组织中的表达较强.结论 明确Prss37的转录起始位点,成功获得了睾丸和附睾表达荧光素酶基因的转基因小鼠,为进一步的Prss37基因转录调控研究奠定了基础.  相似文献   
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