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1.
目的 观察高转换型肾性骨病中骨保护素及其配体 (OPG,RANKL)的表达,并与骨形态计量学指标进行相关分析。 方法 选择10例慢性肾衰尿毒症患者和3例正常人进行髂骨活检术,获得骨组织标本。采用免疫组化方法检测OPG和RANKL蛋白质的表达。采用全自动图像分析系统进行骨组织形态计量学测定。结果 10例慢性肾衰尿毒症患者经骨病理学检查证实均为高转换型骨病,以破骨细胞活化形成骨吸收陷窝伴或不伴骨矿化不全为特点。免疫组化显示尿毒症患者骨组织中以RANKL阳性表达为主。与正常对照相比,RANKL阳性表达细胞数目显著增加,OPG阳性表达细胞数目显著减少。尿毒症患者RANKL的阳性表达细胞数目与骨吸收面积和破骨细胞数目呈显著正相关。结论 高转换型肾性骨病中,PTH的溶骨作用可能是通过OPG/RANKL/RANK系统介导的。  相似文献   
2.
Osteoclastogenesis inhibitory factor (OCIF) is a novel secreted protein that inhibits osteoclastogenesis both in vitro and in vivo. In this study, we examined the effects of OCIF on serum calcium (Ca) concentrations in normal mice and in hypercalcemic nude mice carrying tumors associated with humoral hypercalcemia of malignancy. In normal mice, a single intraperitoneal injection of OCIF reduced serum Ca levels in a dose-dependent manner. Significant decrease in serum Ca (by 1.6 ± 0.3 mg/dL, n = 5) was observed 2 h after the injection of OCIF at 20 mg/kg and the hypocalcemic effect continued for up to 12 h. Serum phosphate (Pi) concentrations also decreased in response to OCIF. Urinary excretion of Ca, Pi, and creatinine did not change significantly after injection of OCIF or vehicle. In hypercalcemic, tumor-bearing nude mice, a single intraperitoneal injection of OCIF at 20 mg/kg resulted in a dramatic decrease in serum Ca (maximal decrease 2.8 ± 0.37 mg/dL, n = 11), which continued for up to 24 h. The results suggest that OCIF decreased serum Ca through its inhibitory effect on bone resorption. Furthermore, it is suggested that OCIF has therapeutic potential for the treatment of hypercalcemic conditions such as malignancy-associated hypercalcemia.  相似文献   
3.
Osteoprotegerin (OPG) is a protein that inhibits of osteoclastogenesis. The aim this study was to evaluate the response of serum OPG levels to neridronate treatment in patients with Paget's disease of bone resistant to previous therapy. Nine patients (4 men) affected by active Paget’s disease of bone (6 polyostotic, 3 monostotic) not responsive to clodronate were studied. Serum OPG, osteocalcin, total and bone isoenzyme of alkaline phosphatase (AP and BAP, respectively), and urinary deoxypyridinoline (DPD) were measured before and 5 months after neridronate treatment (100 mg/day, i.v. for two days). A scintigraphic activity index (SAI) was also calculated before treatment. Mean baseline OPG levels were within normal values and were not significantly different 5 months after neridronate treatment. In contrast, there were significant reductions in AP (41.9%, p<0.02) and BAP (38.8%, p<0.04). Serum OPG levels correlated with DPD (r=0.925) and SAI (r=0.689). Although OPG is an important regulator of bone metabolism, in our series of already treated patients it was not a sensitive marker for diagnosing Paget's disease and for monitoring the response to pharmacological treatment, whereas AP and BAP confirmed their clinical usefulness. This preliminary study requires confirmation by a study with a larger population.  相似文献   
4.
The interaction between receptor activator of nuclear factor-kappaB ligand (RANKL) and RANK has been reported to regulate immunity in addition to bone metabolism. The aim of this study was to determine if osteoprotegerin (OPG), an inhibitor of the RANKL-RANK interaction and possibly a new drug against osteoporosis, would adversely affect immunity. OPG was used to treat mice developing different models of cellular and humoral immune responses and also in vitro in T and B cell assays. In mice, OPG does not affect cell-mediated reactions such as contact hypersensitivity to the hapten oxazolone and liver damage, granuloma formation, and infectious load induced by mycobacterial infection. However, OPG increases humoral reactions such as the production of IgM, IgG, and IgE against the T cell dependent antigen keyhole limpet hemocyanin and the production of IgM against the T cell independent antigen Pneumovax. In vitro, OPG modestly co-stimulates T cells but does not affect the proliferation of B cells. OPG has modest immunoregulatory effects that seem to be confined to the humoral response to specific antigens.  相似文献   
5.

Objectives

Sumac (Rhus coriaria L.) is widely used spice which has several properties such as antioxidant, anti-inflammatory and antimicrobial. The purpose of this animal study was to evaluate the effects of sumac extract on levels of receptor activator of nuclear factor-kappa B ligand (RANKL), osteoprotegerin (OPG) expression, serum oxidative status, and alveolar bone loss in experimental periodontitis.

Material and Methods

Twenty-four Wistar rats were separated into three groups: non-ligated (NL, n=8), ligature only (LO, n=8), and ligature and treated with sumac extract (S, n=8) (20 mg/kg per day for 11 days). A 4/0 silk suture was placed around the mandibular right first molars subgingivally; after 11 days, the rats were sacrificed, and alveolar bone loss was histometrically measured. The detection of RANKL and OPG were immunohistochemically performed. Levels of serum total antioxidant status (TAS)/total oxidant status (TOS), and oxidative stress index (OSI) were also analyzed.

Results

Alveolar bone loss was significantly greater in the LO group compared to the S and NL groups (p<0.05). The number of inflammatory cell infiltrate (ICI) and osteoclasts in the LO group was significantly higher than that of the NL and S groups (p<0.05). The number of osteoblasts in the LO and S groups was significantly higher than that of the NL group (p<0.05). There were significantly more RANKL-positive cells in the LO group than in the S and NL groups (p<0.05). OPG-positive cells were higher in S group than in LO and NL groups (p<0.05). TOS and OSI levels were significantly reduced in S group compared to LO group (P<0.05) and TAS levels were similar in S and NL group (p>0.05).

Conclusions

The present study showed that systemic administration of sumac extract may reduce alveolar bone loss by affecting RANKL/OPG balance, TOS and OSI levels in periodontal disease in rats.  相似文献   
6.
目的探讨肿瘤坏死因子α( TNF-α)、白介素-1β( IL-1β)、血清骨保护素( OPG)与2型糖尿病合并冠心病的关系。方法入选健康个体(对照组)和2型糖尿病合并冠心病患者(冠心病组)各30例,用ELISA方法测定TNF-α、IL-1β、OPG,生化法测定血糖及糖化血红蛋白,并观察组间各指标的变化及相互关系。结果2型糖尿病合并冠心病组血清空腹血糖、糖化血红蛋白、OPG明显高于对照组( P均<0.01), TNF-α、IL-1β高于对照组( P均<0.05)。 Spearman 相关分析显示, OPG与 TNF-α、IL-1β呈显著正相关( P 均<0.01)。结论血糖、糖化血红蛋白、TNF-α、IL-1β、OPG在2型糖尿病合并冠心病患者中明显增高,OPG与TNF-α、IL-1β改变有关。  相似文献   
7.
目的 探讨不同浓度淫羊藿苷抑制牙龈卟啉单胞菌超声提取物对人牙周膜细胞增殖及骨保护素(OPG)表达的影响.方法 体外培养人牙周膜细胞,用四唑盐(MTT)法检测不同浓度淫羊藿苷(0、0.001、0.01、0.1、1 μg/ml)及50μg/ml牙龈卟啉单胞菌超声提取物,不同时间(24、48、72h)作用下人牙周膜细胞的增殖水平.用RT-PCR及Western blot检测48h人牙周膜细胞骨保护素mRNA和蛋白的表达.结果 淫羊藿苷从0.01~1μg/ml对人牙周膜细胞增殖及骨保护素mRNA和蛋白的表达有促进作用(P<0.01),浓度为0.1μg/ml作用最显著.结论 淫羊藿苷可抑制牙龈卟啉单胞菌超声提取物对人牙周膜细胞增殖及骨保护素mRNA和蛋白表达的影响,促进人牙周膜细胞增殖及骨保护素mRNA和蛋白表达.  相似文献   
8.
[摘要]目的:观察人骨保护素(humanosteoprotegerin,hOPG)在犬牙周韧带细胞(periodontalligamentcells,PDLCs)中的表达情况,为后期的牙周组织再生实验制备高表达目的基因hOPG的种子细胞。方法:体外构建携带hOPG基因的腺病毒载体Ad5-hOPG—EGFP,并将其转染Beagle犬PDLCs,通过流式细胞术、实时定量RT.PCR、ELISA以及WesternBlot检测目的基因的转录和表达。结果:重组腺病毒Ad5一hOPG—EGFP成功转染犬PDLCs,转染72h后转染效率达到80%以上,转染的细胞发出较强的绿色荧光;基因和蛋白水平检测表明,hOPG在犬PDLCs中得到了有效表达。结论:重组腺病毒介导的hOPG基因可以在PDLCs中有效表达。  相似文献   
9.
目的 探讨骨保护素基因(TNFRSF11B) 1181G>C(rs2073618)、163A>G(rs3102735)位点和核因子κB活化因子受体配体(RANKL)基因(TNFRSF 11)401A>G (rs2277438)位点单核苷酸多态性(SNP)对类风湿关节炎(RA)疾病易感性及其骨密度和疾病活动性的影响.方法 采用连接酶检测反应(LDR)聚合酶链反应(PCR)方法检测200例RA患者和201名健康对照组骨保护素基因rs2073618、rs3102735位点和RANKL基因rs2277438位点SNP;采用双能X线骨密度仪(DEXA)法测定其股骨和腰椎部位骨密度.比较其等位基因分布频率、基因型频率及单倍体型在2组中的分布,并比较不同基因型RA患者骨密度及疾病活动性的差别.统计学方法采用方差分析,t检验和x2检验.结果 ①骨保护素基因rs2073618位点、rs3102735位点和RANKL基因rs2277438位点各等位基因及基因型分布频率在RA组与对照组中差异均无统计学意义(P>0.05).3个位点单倍体型研究表明:骨保护素和RANKL基因单倍体型(rs2073618G-rs2277438G-rs3102735G)携带者RA疾病易感性明显降低(1.5%与6.0%,OR:0.216,95%CI:0.081~0.575,P=0.0008),骨保护素和RANKL基因单倍体型(rs2073618G-rs2277438A-rs31 02735G)携带者RA易感性明显增加(14.5%与8.4%,OR:1.862,95%CI:1.179~2.943,P=0.007).②RANKL基因rs2277438位点表达为纯合型(AA和GG型)的RA患者(62例)腰椎3(1.05±0.22与0.93±0.26,t=2.314,P=0.023)、腰椎4(1.06±0.24与0.94±0.28,t=2.207,P=0.030)、腰椎2~4(1.04±0.21与0.89±0.28,t=2.788,P=0.007)部位骨密度均明显高于杂合型(AG型)RA患者(39例);骨保护素基因rs2073618和rs3102735位点不同基因型RA患者间骨密度差异无统计学意义(P>0.05).③骨保护素基因rs2073618位点表达为纯合型(CC、GG型)的RA患者(60例)在以下疾病活动性指标上明显高于表达为杂合型(CG型)的RA患者(40例):压痛关节数(13±7与10±6,t=2.154,P=0.034)、压痛关节指数(19±11与13±9,t=2.318,P=0.023)、疼痛视觉模拟(VAS)评分(5.7±1.9与4.8±1.8,t=2.481,P=0.015).RANKL基因rs2277438位点、骨保护素基因rs3102735位点不同基因型RA患者间各疾病活动性指标差异无统计学意义(P>0.05).结论 骨保护素基因rs2073618、rs3102735位点和RANKL基因rs2277438位点SNP与中国籍汉族RA患者易感性无关,但骨保护素和RANKL基因单倍体型(rs2073618G-rs2277438G-rs3102735G)为RA的保护性因素,而单倍体型(rs 2073618G-rs2277438A-rs31 02735G)是危险因素.RANKL基因rs2277438位点SNP与RA骨代谢相关;骨保护素基因rs2073618位点SNP与RA患者疾病活动性相关.  相似文献   
10.
探讨系统性红斑狼疮(SLE)合并骨质疏松症(OP)患者血清骨保护素(OPG)检测的临床意义;【方法】采用酶联免疫吸附试验检测50例女性SLE患者(16例合并OP)和30例女性健康志愿者外周血清OPG水平,采用单因素方差分析比较OP组、非OP组、健康志愿组血清OPG水平差异,采用Pearson相关检验分析血清OPG水平与25-OH维生素D3水平的相关性,采用受试者工作特征曲线(ROC)分析血清OPG水平判断SLE合并OP的敏感性和特异性。【结果】SLE合并OP组血清OPG水平显著高于非OP组及健康志愿组(217.7pg/mlVS 116.0pg/ml VS 87.1pg/ml,P〈0.01);SLE患者血清OPG水平与25-OH维生素D3水平显著负相关(r=-0.439,P〈0.01);以血清OPG水平120pg/ml作为判断SLE是否合并OP的临界值,诊断敏感性为75.0%,特异性为61.8%。【结论】OPG与SLE合并OP有关,检测其血清水平对判断SLE是否合并OP可能具有一定的临床价值。  相似文献   
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