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1.
Chondroitin sulfates were isolated from the mud snail. For the quantitative analysis of enzymatic digestion products of isolated chondroitin sulfates, strong anion exchange-high performance liquid chromatography (SAX-HPLC) was performed. By the action of chondroitinase ABC, three unsaturated disaccharides 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-D-galactose (ΔDi-OS), 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-6-O-sulfo-D-galactose (ΔDi-6S) and 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-4-O-sulfo-D-galactose (ΔDi-4S) were produced from the mud snail chondroitin sulfates. The analysis showed that relative proportion of ΔDi-OS/ΔDi-6S/ΔDi-4S was 58.7/3.1/38.2. The immunomodulating activity of chondroitin sulfate was examined by cell proliferation assay and these results suggest that it might be a immunosuppressant.  相似文献   
2.
We report a patient with a progressive, predominantly sensory neuropathy and a IgM kappa M-protein that binds to Schmidt-Lantermann incisures. A sural nerve biopsy showed primary axonal damage and IgM deposits at Schmidt-Lantermann incisures were seen by direct immunoperoxidase. Serum from the patient injected into rat sciatic nerve reacts with the incisures as with those in the patient's nerve. The IgM kappa M-protein reacts with chondroitin sulfate C and binds to a broad nerve protein band with a mobility of between 170 and 118 kDa. Peripheral neuropathy may be related to the M-protein, which had immunocytochemical reactivity not previously described for patients with polyneuropathy and IgM monoclonal gammopathy.  相似文献   
3.
离子色谱法测定硫酸软骨素的含量   总被引:15,自引:0,他引:15       下载免费PDF全文
建立了用离子色谱法测定硫酸软骨素的方法。在6mol/L盐酸介质中将硫酸软骨素水解生成等摩尔的硫酸根离子,然后用AnionHC离子色谱柱进行分离,以硼酸钠/葡萄糖酸钠淋洗液为流动相,流速1.5ml/min,电导检测器检测。硫酸根离子在0.001~0.080mg/ml浓度范围内线性关系良好,相关系数为0.9994,最低检测浓度为0.0006mg/ml。样品中硫酸根离子的加样回收率为98.51%~99.52%,硫酸软骨素原料药和注射液及鲨鱼软骨粉胶囊中硫酸软骨素测定的相对标准偏差分别为0.25%,1.06%和1.96%。该方法已应用于多种硫酸软骨素制剂中硫酸软骨素的含量测定  相似文献   
4.
目的观察颞下颌关节紊乱病(TMD)患者关节滑液中硫酸软骨素(CS)的含量变化,探讨其在TMD诊断中的价值.方法用高效液相色谱法检测10例正常人颞下颌关节(对照组)、32例颞下颌关节结构紊乱病(ID组)、28例颞下颌关节骨关节病(OA组)患者关节滑液中CS不饱和二糖ΔDi-6S与ΔDi-4S.结果三组关节滑液中均能检测出ΔDi-6S,ID组及OA组均检测到ΔDi-4S,对照组仅有3例检测到痕量ΔDi-4S.ΔDi-6S与ΔDi-4S含量在ID组及OA组均高于对照组(P均<0.001),OA组亦高于ID组(P<0.01).结论 TMD患者关节滑液中CS含量增加,且随病变的加重CS含量增加,其可以作为一种生化标志用于TMD的早期诊断.  相似文献   
5.
目的:探讨人突变Lumican基因转基因小鼠生后不同时间屈光状态及其变化特征。方法实验研究。54只(雄性27只,雌性27只)人突变Lumican基因(cDNA 596T>C)转基因小鼠,于生后3、4、5、6、8、10、12、16、20周共9个时间点分别通过随机数字表法随机选取6只(雄性3只,雌性3只)转基因小鼠,快速散大瞳孔后检影验光测量屈光度数。对比相同时间点转基因小鼠双眼间及雌雄性别间的屈光度数,采用配对t检验;不同时间点转基因小鼠屈光度数的比较采用非参数多个独立样本Kruskal?Wallis H检验,两两组间屈光度数比较采用非参数两个独立样本Mann?Whitney U检验。结果同周龄组转基因小鼠双眼间比较屈光度数差异无统计学意义:第20周转基因小鼠右左眼屈光度均值分别是(1.50±0.45)和(1.25±0.42)D,(t=-0.889,P>0.05),第3周转基因小鼠右左眼屈光度均值分别是(-2.50±2.59)和(-2.50±4.32)D,(t=0.000,P>0.05);同周龄组不同性别转基因小鼠眼间比较屈光度数差异无统计学意义:第3周转基因小鼠雌雄性别眼屈光度均值分别是(-0.5±3.83)和(-4.17±1.94)D,(t=2.079,P>0.05),第12周转基因小鼠雌雄性别眼屈光度均值分别是(1.50±0.84)和(1.50±1.87)D(t=0.000,P>0.05);不同周龄组转基因小鼠屈光度数差异有统计学意义(H=20.910,P<0.05);两两组间比较显示转基因小鼠第3周与第6周屈光度数差异有统计学意义(Z=-3.259,P<0.001),其余各周之间比较屈光度数差异均无统计学意义(P>0.001)。结论人突变Lumican基因转基因小鼠出生后3周时为近视,随时间增加向远视发展,第6周远视屈光度数达到最大,8~20周时远视屈光度数逐渐减小并趋于稳定。(中华眼科杂志,2015,51:527-531)  相似文献   
6.
Platelet derived growth factor (PDGF) is involved in the autocrine growth stimulation of normal and malignant cells, the stimulation of angiogenesis, and the recruitment and regulation of tumor fibroblasts. PDGF has been shown to physically interact with glycosaminoglycans which are abundant in the extracellular microenvironment. The present review discusses the effects of glycosaminoglycans on the functions mediated by the PDGF on cells of mesenchymal origin. Recent studies have demonstrated that both soluble and surface bound glycosaminoglycan chains can modulate PDGF-BB isoform signaling depending on the cell type. These data demonstrated that the microenvironment rich in GAGs/PGs is able to significantly modify the cellular response to PDGF-BB signaling in a critical way for cell growth and differentiation.  相似文献   
7.
The effects of factors such as age and sex on the metabolism of chondroitin sulfate (CS) and hyaluronic acid (HA) in knee joint tissues are believed to be profoundly important in the onset of joint diseases including osteoarthritis. To test whether age and sex influence CS isomers and HA in normal synovial fluid, we determined concentrations of chondroitin 6-sulfate (C6S), chondroitin 4-sulfate (C4S), and HA in healthy subjects of different ages. Synovial fluids were obtained from 187 healthy volunteers, 14–89 years of age. Chondroitin 6-sulfate, C4S, HA concentrations, and C6S : C4S ratio showed a significant negative correlation with age. There were no sex-related differences in HA concentration, but the concentrations of C6S and C4S and the C6S : C4S ratio were significantly lower in women than in men in most age groups.  相似文献   
8.
AIM: To investigate the expression of chondroitin sulphate proteoglycans (CSPGs) in rat liver tissues of hepatocellular carcinoma (HCC).METHODS: Thirty male Sprague Dawley rats were randomly divided into two groups: control group (n = 10) and HCC model group (n = 20). Rats in the HCC model groups were intragastrically administrated with 0.2% (w/v) N-diethylnitrosamine (DEN) every 5 d for 16 wk, whereas 0.9% (w/v) normal saline was administered to rats in the control group. After 16 wk from the initiation of experiment, all rats were killed and livers were collected and fixed in 4% (w/v) paraformaldehyde. All tissues were embedded in paraffin and sectioned. Histological staining (hematoxylin and eosin and Toluidine blue) was performed to demonstrate the onset of HCC and the content of sulphated glycosaminoglycan (sGAG). Immunohistochemical staining was performed to investigate the expression of chondroitin sulphate (CS)/dermatan sulphate (DS)-GAG, heparan sulphate (HS)-GAG, keratan sulphate (KS)-GAG in liver tissues. Furthermore, expression and distribution of CSPG family members, including aggrecan, versican, biglycan and decorin in liver tissues, were also immunohistochemically determined.RESULTS: After 16 wk administration of DEN, malignant nodules were observed on the surface of livers from the HCC model group, and their hepatic lobule structures appeared largely disrupted under microscope. Toluidine blue staining demonstrated that there was an significant increase in sGAG content in HCC tissues when compared with that in the normal liver tissues from the control group [0.37 ± 0.05 integrated optical density per stained area (IOD/area) and 0.21 ± 0.01 IOD/area, P < 0.05]. Immunohistochemical studies demonstrated that this increased sGAG in HCC tissues was induced by an elevated expression of CS/DS (0.28 ± 0.02 IOD/area and 0.18 ± 0.02 IOD/area, P < 0.05) and HS (0.30 ± 0.03 IOD/area and 0.17 ± 0.02 IOD/area, P < 0.01) but not KS GAGs in HCC tissues. Further studies thereby were performed to investigate the expression and distribution of several CSPG components in HCC tissues, including aggrecan, versican, biglycan and decorin. Interestingly, there was a distinct distribution pattern for these CSPG components between HCC tissues and the normal tissues. Positive staining of aggrecan, biglycan and decorin was localized in hepatic membrane and/or pericellular matrix in normal liver tissues; however, their expression was mainly observed in the cytoplasm, cell membranes in hepatoma cells and/or pericellular matrix within HCC tissues. Semi-quantitative analysis indicated that there was a higher level of expression of aggrecan (0.43 ± 0.01 and 0.35 ± 0.03, P < 0.05), biglycan (0.32 ± 0.01 and 0.25 ± 0.01, P < 0.001) and decorin (0.29 ± 0.01 and 0.26 ± 0.01, P < 0.05) in HCC tissues compared with that in the normal liver tissues. Very weak versican positive staining was observed in hepatocytes near central vein in normal liver tissues; however there was an intensive versican distribution in fibrosis septa between the hepatoma nodules. Semi-quantitative analysis indicated that the positive rate of versican in hepatoma tissues from the HCC model group was much higher than that in the control group (33.61% and 21.28%, P < 0.05). There was no positive staining in lumican and keratocan, two major KSPGs, in either normal or HCC liver tissues.CONCLUSION: CSPGs play important roles in the onset and progression of HCC, and may provide potential therapeutic targets and clinical biomarkers for this prevalent tumor in humans.  相似文献   
9.
硫酸软骨素蛋白多糖(chondroitin sulfate proteoglycan,CSPG)是在发育和成熟的中枢神经系统(central nervous syste,CNS)中广泛表达的一组细胞外基质分子,在胚胎CNS发育和成年期CNS可塑性中发挥着重要作用.CSPG作为一种主要的细胞外抑制性成分,可影响CNS损伤后轴突再生和神经功能恢复.  相似文献   
10.
目的 探讨成肌细胞种植于聚乳酸聚乙酸共聚物(PLGA)支架上,软骨定向诱导后植入比格犬体内修复半月板缺损的可能性.方法 将来源于比格犬的成肌细胞培养传代至第4代,收集后以5.0×106细胞/cm3材料体积密度将细胞接种于PLGA支架中,含50 ng/ml软骨源性形态发生蛋白-2(CDMP-2)和20 ng/ml转化生长因子β1(TGF-β1)软骨诱导培养基培养14 d.然后将细胞-支架复合体植入24只比格犬半月板缺损模型中,术后4、8、12周取材,采用大体观察、组织学、生物化学和生物力学作为评估指标.结果 术后4、8、12周各项检测结果显示PLGA支架材料逐渐降解吸收,而成肌细胞可逐渐合成分泌新生胶原,并最终形成半月板样纤维组织,而对照各组缺损区则仅见少许纤维组织样的修复组织.结论 利用成肌细胞经体外扩增及细胞因子刺激后,以PLGA支架为载体,按一定的细胞密度复合培养后,植入关节腔内修复半月板局部缺损的方法,是一种较为可行的修复半月板损伤的方法.  相似文献   
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