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排序方式: 共有1410条查询结果,搜索用时 15 毫秒
1.
The abnormal expression of long noncoding RNAs (lncRNAs) is frequently observed in gastric cancer (GC) and considered an important driving force in GC progression. However, little is known regarding the involvement of TMEM147-AS1 in GC. Therefore, we examined TMEM147-AS1 expression in GC and determined its prognostic value. In addition, TMEM147-AS1 expression was depleted to identify the functional changes in response to TMEM147-AS1 deficiency. Using the cancer genome atlas dataset and our own cohort, we identified a strong expression of TMEM147-AS1 in GC. Increased TMEM147-AS1 levels in GC showed a significant association with poor prognosis. TMEM147-AS1 interference resulted in the inhibition of GC cell proliferation, colony-forming, migration, and invasion in vitro. Additionally, depletion of TMEM147-AS1 restricted the growth of GC cells in vivo. Mechanistically, TMEM147-AS1 functioned as a microRNA-326 (miR-326) sponge. Furthermore, SMAD family member 5 (SMAD5) was experimentally validated as the functional effector of miR-326. TMEM147-AS1 was demonstrated to sequester miR-326 away from SMAD5; consequently, knocking down TMEM147-AS1 downregulated SMAD5 levels in GC cells. The functional suppression of miR-326 or reintroduction of SMAD5 effectively reversed the attenuated behavior of GC cells caused by TMEM147-AS1 downregulation. In summary, TMEM147-AS1 exhibits tumorigenic activities in GC, which is likely the result of an altered miR-326/SMAD5 axis. Therefore, targeting TMEM147-AS1/miR-326/SMAD5 may represent a target for the treatment of GC.  相似文献   
2.
BackgroundIn recent years, transcatheter arterial embolization (TAE) using imipenem/cilastatin (IPM/CS) has attracted attention as a treatment for relieving osteoarthritis (OA) pain. However, IPM/CS is not approved by Japanese medical insurance for use as an embolic material. Therefore, it is necessary to develop new embolic materials for TAE to relieve OA pain. The purpose of this study was to develop a swine model of knee arthritis and embolize abnormal neovessels (ANs) using two different embolic materials. We compared the embolic effects and tissue damage in knees.MethodsKnee arthritis was induced by intra-articular injection of papain into 12 knees in six female swine. The swine were divided into two groups of three swine each (six knees per group) for embolization of ANs in the knees with either IPM/CS or soluble gelatin sponge particles (SGSs). Three days after embolization, we compared the embolic effects using angiography and the tissue damage histopathologically.ResultsANs were observed in all 12 knees at 42 days after papain injection. The ANs disappeared and the patent arteries were recanalized 3 days after TAE in all 12 knees. Histopathological evaluation revealed synovitis changes, such as synovial thickening and inflammatory cell infiltration, in all 12 knees. There was no evidence of skin or muscle necrosis in either group. The appearance of ANs, recanalization of the parent arteries, and histopathological outcomes were not significantly different between the two groups.ConclusionSGSs were as safe as IPM/CS for TAE of ANs in this swine model of knee arthritis.  相似文献   
3.
目的研究养殖喘水苔海绵Tedania anhelans化学成分及其生物活性,为药源海绵规模化养殖和开发提供依据。方法综合利用薄层色谱、硅胶色谱、ODS C18色谱、Sephadex LH-20凝胶柱色谱、半制备高效液相色谱(HPLC)等方法对化学成分进行了分离;通过质量光谱测定(MS)、核磁共振(NMR)等方法并结合相关文献,对化合物结构进行鉴定。结果从养殖喘水苔海绵Tedania anhelans中分离得到13个化合物,分别为胆固醇(1)、3β-羟基-24-亚甲基胆甾-5-烯-7-酮(2)、胆甾-5-烯-3β,7α-二醇(3)、胆甾-5-烯-3β,7β-二醇(4)、3β-羟基胆甾-5-烯-7-酮(5)、胸苷(6)、去甲基胸苷(7)、环(脯氨酸-缬氨酸)二肽(8)、piperazirum(9)、(E)-4-(1H-indol-3-yl)but-3-en-2-one(10)、3-吲哚乙酸甲酯(11)、3-吲哚甲醛(12)、毛脉五味子醇(13)。结论13个化合物均为首次从该种海绵中分离得到,化合物8在50μmol·L?1浓度水平对HSV-2病毒抑制率为60.7%。  相似文献   
4.
目的:构建微小RNA-186(miR-186)基因的海绵载体,建立稳定敲减miR-186的EA.hy926细胞株。方法:化学合成miR-186海绵体序列,并克隆到慢病毒FV040表达载体上;采用lipofectamine 2000共转染FV040-miR-186-sponge载体和慢病毒辅助包装质粒到HEK293T细胞,包装慢病毒,测定病毒滴度;FV040-control慢病毒作为对照组,FV040-miR-186-sponge作为实验组,分别感染EA.hy926细胞,筛选稳转细胞株;采用荧光定量PCR (qPCR)法检测空白对照组、FV040-control对照组及FV040-miR-186-sponge实验组中EA.hy926细胞miR-186的相对表达水平。结果:测序结果显示克隆的目的基因序列与设计的miR-186海绵体序列完全一致。在感染的EA.hy926细胞中观察到绿色荧光蛋白(GFP)的表达。FV040-control包装的慢病毒滴度为2×108 TU·mL-1,FV040-miR-186-sponge组慢病毒滴度为6×108 TU·mL-1;成功建立了稳定表达miR-186-sponge的EA.hy926细胞株,感染效率达95%;qPCR检测,与空白对照组和FV040-control组比较,FV040-miR-186-sponge组EA.hy926细胞中miR-186相对表达水平降低(P<0.01)。结论:成功构建了miR-186基因的海绵载体,建立了稳定下调miR-186表达的EA.hy926-miR-186-sponge细胞株。  相似文献   
5.
Blood transfusion, using the safest conventional blood bioproducts, is an irreplaceable part of substitution therapy. It is considered the most essential supportive clinical intervention aimed to restore the health of patients in need. Nevertheless, numerous unresolved problems are still associated with current blood substitution therapy. To alleviate our dependency on blood donors, many investigators have been focusing on the quest for stem cell-derived blood cells in line with major developments in the field of regenerative medicine. The main objective is to provide a safe and highly standardized universal cultured red cell concentrate [CRBC] for all clinical applications, regardless of blood groups. Currently, we are close to overcoming some of the main obstacles in culturing cells. This concise report is a prelude to the immortalized cell lines that are ready for in vivo clinical trials. It is only through the sharing of experimental ideas and knowledge-based strategies that we will be able to achieve such an enormous task and better understand ‘’the one for all concept’’ of CRBCs and their universal usage in all clinical settings.  相似文献   
6.
目的:探讨丹银海绵对糖尿病大鼠皮肤溃疡创面愈合的影响。方法:将雄性Wistar大鼠随机分为8组。除空白对照组外,其余7组大鼠,通过手术在其背部形成一10mm×10mm相同大小,深达肌层的溃疡,分别给予抗生素、生长因子凝胶、纳米银、丹黄散,以及不同浓度的丹银海绵处理溃疡面。给药28d后处死大鼠,取溃疡部位新生肉芽组织,HE染色观察组织形态的变化;WesternBlot检测大鼠创面组织中AGEs、hs-CRP、IL-1、IL-6、bFGF、PDGF、VEGF表达水平。结果:病理切片观察显示适宜浓度的丹银海绵可以促进血管新生并伴扩张,同时生成大量新生成纤维细胞。WesternBlot检测显示高浓度的丹银海绵可以显著上调创面组织中生长因子表达(P<0.05),降低AGEs水平及炎症因子表达(P<0.05)。结论:适宜浓度的丹银海绵对于糖尿病大鼠皮肤溃疡的愈合有明显的促进作用,提高治疗效果。  相似文献   
7.
8.
目的:探讨白藜芦醇对单次和双次氧-葡萄糖剥夺(oxygen-glucose deprivation, OGD)原代皮质神经元沉默信息调节因子1(silent information regulator 1, SIRT1)、AMP 活化的蛋白激酶(AMP-activated protein kinase, AMPK)活性和 ATP 含量的影响及其可能的神经保护机制。方法皮质神经元取自18 d Wistar 大鼠胚胎,原代培养成功后通过2次OGD 制作体外反复缺血模型。采用台盼蓝染色法检测细胞存活率,蛋白质印迹法检测 SIRT1和磷酸化 AMPK 表达,去乙酰化酶荧光检测法检测 SIRT1活性,生物发光测定法检测 ATP 含量。结果与对照组比较,白藜芦醇(0.5μmol/L)预处理能显著增高单次和双次 OGD 后存活率(P 均<0.001)、ATP 含量(P 均=0.004)、SIRT1活性(单次:P =0.001;双次:P =0.002)以及 SIRT1(单次:P =0.029;双次:P =0.023)和磷酸化 AMPK (P 均=0.001)表达水平。结论白藜芦醇对单次和双次 OGD 皮质神经元均具有神经保护作用,其机制可能与上调 SIRT1/AMPK 通路和降低能量需求有关。  相似文献   
9.
Rationale:Medullary sponge kidney (MSK) is a congenital renal disorder characterized by recurrent nephrolithiasis or nephrocalcinosis. Recently, it has been found that MSK can be also combined with other diseases, such as primary aldosteronism and Beckwith-Wiedemann, but whether it is associated with secondary hypertension remains unknown.Patient concerns:A 22-year-old hypertensive female presented to our hospital characterized by hypokalemia and hypertension.Diagnosis:The laboratory examination showed secondary aldosteronism. And the common causes for secondary aldosteronism include renal artery stenosis, glomerulonephritis, lupus nephropathy, and diabetic nephropathy, all of which were excluded except MSK.Interventions:She was treated with angiotensin-converting enzyme inhibitors.Outcomes:Her blood pressure, serum potassium, and plasma renin levels were reversed after treatment with angiotensin-converting enzyme inhibitors.Lessons:We presumed that MSK may be associated with secondary hypertension, and the mechanism may be the activation of the renin-angiotensin-aldosterone system.  相似文献   
10.
Objective: Despite advanced treatment options available, drug resistance develops in breast cancer (BC) patientsrequiring novel effective drugs. Stylissa carteri, a marine sponge predominantly living in Indonesia territories, hasnot been extensively studied as anti-cancer. Therefore, this study targeted to assess the anti-tumor activity of theethanol extract of S. carteri in BC cells. Methods: S. carteri was collected from Pramuka Island, at Kepulauan SeribuNational Park, Jakarta, Indonesia and extracted using ethanol. Different BC cells including MDA MB 231, MDAMB 468, SKBR3, HCC-1954 and MCF-7 cells were treated with this extract for cytotoxic analysis using MTT assay.Spheroid growth assay and apoptosis assay were conducted in HCC-1954 cells. In addition, cell migration analysis andsynergistic activity with doxorubicin or paclitaxel were conducted in MDA MB 231 cells. This extract was subjectedalso for GC-MS analysis. Results: The results show that ethanol extract of S. carteri demonstrated a cytotoxic activityin BC cells. The IC50 of this extract was lower 15 μg/ml in MDA MB 231, MDA MB 468, SKBR3, and HCC-1954cells. Moreover, this extract inhibited spheroids growth and induced apoptosis in HCC-1954 cells. It inhibited cellmigration and demonstrated a synergistic activity with doxorubicin or paclitaxel on triggering cell death in MDA MB231 cells. Furthermore, GC-MS analysis indicated that this extract contained 1,2-Benzenediol, Dibutyl phthalate and9,12-Octadecadienoic acid, ethyl ester. Conclusion: Our preliminary data indicate a potential anti-tumor activity ofethanol extract of S. carteri in breast cancer cells.  相似文献   
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