首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   74篇
  免费   3篇
  国内免费   1篇
妇产科学   14篇
基础医学   7篇
口腔科学   1篇
临床医学   7篇
内科学   15篇
神经病学   1篇
外科学   4篇
综合类   12篇
预防医学   6篇
药学   5篇
中国医学   4篇
肿瘤学   2篇
  2023年   1篇
  2022年   2篇
  2021年   2篇
  2020年   1篇
  2019年   4篇
  2018年   3篇
  2017年   2篇
  2016年   2篇
  2014年   2篇
  2013年   1篇
  2012年   4篇
  2011年   6篇
  2010年   2篇
  2008年   2篇
  2007年   3篇
  2006年   1篇
  2005年   4篇
  2004年   8篇
  2003年   7篇
  2002年   1篇
  2001年   4篇
  2000年   8篇
  1999年   3篇
  1998年   1篇
  1997年   1篇
  1994年   2篇
  1987年   1篇
排序方式: 共有78条查询结果,搜索用时 15 毫秒
1.
目的探讨含银介孔二氧化硅-壳聚糖复合材料(Ag/MSN-Chi)的制备方法及其微观表征、细胞毒性、吸水性能、抗菌性能及止血性能。 方法以正硅酸乙酯为前驱体,十六烷基三甲基溴化铵为致孔剂,采用离子交换法在介孔二氧化硅纳米粒子(MSN)中引入银离子,制备出具有抗菌作用的新型有序的含银介孔二氧化硅纳米粒子(Ag/MSN)材料。再利用烷基化壳聚糖负载Ag/MSN,制备出Ag/MSN-Chi。根据所用材料不同将实验分为实验组和空白对照组,实验组又分为3个亚组:MSN组、Ag/MSN组、Ag/MSN-Chi组,空白组为不加任何材料的阳性对照。计算MSN和Ag/MSN的比表面积、孔容、孔径和Ag/MSN与Ag/MSN-Chi的电荷。并通过吸水实验、体外凝血实验、抗菌实验对MSN、Ag/MSN和Ag/MSN-Chi的细胞毒性、吸水性能、止血性能及抗菌性能进行评价,计算细胞相对存活率、吸水率、凝血酶原时间(PT)、凝血活酶时间(APTT)及抑菌率。取健康成年新西兰大白兔18只,随机分成3组:对照组(采用医用纱布处理)、Ag/MSN组(采用Ag/MSN处理)、Ag/MSN-Chi组(采用Ag/MSN-Chi处理),每组6只,建立肝创伤出血模型,计算止血时间。数据比较采用方差分析和t检验。 结果MSN的比表面积为(523.8±12.4) m2/g、孔容为(1.2±0.4) m3/g、孔径为(3.5±0.9) nm;Ag/MSN的比表面积为(521.6±11.7) m2/g、孔容为(1.15±0.5) m3/g、孔径为(3.6±0.7) nm,2种材料的比表面积、孔容、孔径比较差异均无统计学意义(t=0.224、0.135、0.015,P值均大于0.05)。经测量,Ag/MSN的Zeta电位为-19.7 mV,Ag/MSN-Chi的Zeta电位为10.27 mV,表明Ag/MSN表面电荷从负值变为正值。Ag/MSN-Chi组、Ag/MSN组和MSN组与小鼠成肌细胞共培养1、4、7 d的细胞相对存活率比较,差异均无统计学意义(F=2.61、4.72、3.52, P值均大于0.05)。Ag/MSN组吸水率分别与MSN组和Ag/MSN-Chi组比较,差异均无统计学意义(t=0.482、1.159,P值均大于0.05)。经检测,Ag/MSN-Chi组、Ag/MSN组、MSN组和空白对照组的PT比较,差异无统计学意义(F=10.28,P>0.05);Ag/MSN-Chi组、Ag/MSN组、MSN组和空白对照组APTT分别为(20.9±2.1)、(28.5±3.4)、(31.4±2.6)、(38.7±2.5) s,4组比较差异有统计学意义(F=8.70,P<0.05);Ag/MSN-Chi组、Ag/MSN组、MSN组APTT分别与空白对照组比较,差异均有统计学意义(t=9.443、4.186、3.506,P值均小于0.05);Ag/MSN-Chi组APTT与Ag/MSN组比较,差异有统计学意义(t=3.294,P<0.05)。MSN组在培养0.5、2、4、6、24 h 5个时间点抑菌率比较差异无统计学意义(F=5.437,P>0.05);培养0.5 h,Ag/MSN组和Ag/MSN-Chi组抑菌率分别为(99.7±5.2)%、(97.1±5.4)%,与培养0.5 h MSN组抑菌率(11.2±5.8)%比较,差异均有统计学意义(t=19.678、18.775, P值均小于0.05);培养24 h,Ag/MSN组和Ag/MSN-Chi组抑菌率分别为(73.2±5.1)%和(72.9±6.9)%,与MSN组(11.8±5.7)%比较,差异均有统计学意义(t=13.904、11.825, P值均小于0.05)。Ag/MSN-Chi组、Ag/MSN组和对照组止血时间分别为(12.3±1.5)、(17.2±3.4)、(28.1±3.8) s,3组比较差异有统计学意义(F=5.892,P<0.05);Ag/MSN-Chi组和Ag/MSN组止血时间分别与对照组比较,差异均有统计学意义(t=9.473、5.236, P值均小于0.05);且Ag/MSN-Chi组与Ag/MSN组止血时间比较,差异有统计学意义(t=3.230,P<0.05)。 结论Ag/MSN-Chi在不增加细胞毒性的基础上具有有较好的吸水性能、止血性能及抗菌性能。  相似文献   
2.
目的 :探讨子痫对围产儿的影响。方法 :回顾 8年间 4 2例子痫与早产、胎儿宫内窘迫、终止妊娠时机及新生儿窒息的关系 ,并分析子痫对围产儿的影响。结果 :4 2例子痫中早产、胎儿宫内窘迫、新生儿窒息的发生率较高。结论 :控制子痫的发生是提高围产儿质量重要措施之一  相似文献   
3.
Next-generation orthopedic implants with both osteoinductivity and antibacterial ability are greatly needed. In the present study, biodegradable rhBMP-2 loaded zein-based scaffolds with a macroporous structure were synthesized, and SBA-15 nanoparticles and hydroxypropyltrimethyl ammonium chloride chitosan (HACC) were incorporated into the scaffolds to produce an anti-infective composite scaffold for delivery of osteogenic factors that facilitate the functional repair of bone defects. The silica/HACC/zein scaffolds developed here showed bioactivity, biocompatibility, and effective antibacterial activity. Confocal laser scanning microscopy (CLSM) was used to quantitatively measure the bactericidal efficacy with respect to bacterial adhesion. Results showed that the sample zein-HACC-S20 exhibited long-lasting antibacterial activity against Escherichia coli and Staphylococcus aureus up to 5 d. At a low dosage of rhBMP-2 (ca. 80 μg), the scaffolds released rhBMP-2 protein efficiently at a relatively slow rate, even after 27 d. An ALP activity and ECM mineralization assay showed that the zein-HACC-S20 scaffolds exhibited significant early osteogenic differentiation by generating enhanced ALP product on day 14 and ECM mineralization on day 21. In a mouse model of thigh muscle pouches, zein-S20 and zein-HACC-S20 groups resulted in obvious bone formation and gave more extensive mineralization to the implants than silica free groups, indicating effective bone induction in vivo. In a rabbit model of critical-sized radius bone defects (20 mm in length and 5 mm in diameter), the bone defects were almost fully repaired and bone marrow cavity recanalization was detectable by 3D micro-CT technique and histological analysis after 12 weeks. In this way, the zein-HACC-S20 scaffolds were proven to significantly promote the bone repair. They also demonstrated considerable promise for tissue engineering. Silica/HACC/zein scaffolds with both antibacterial activity and the ability to induce osteogenesis have immense potential in orthopedics and other biomedical applications.  相似文献   
4.
钉螺一氧化氮合酶分布的酶组织化学研究   总被引:9,自引:3,他引:9  
目的 定位研究一氧化氮合酶(NOS)在日本血吸虫中间宿主-钉螺体内分布及活性。方法 用还原型尼可酰胺腺嘌呤二核苷酸磷酸硫辛酰胺脱氢酶(NADPH-d)酶组织化学技术,对钉螺软体的整体连续切片作系统观察。结果 头足部肌纤维间含丰富NOS阳性神经元;中枢神经节纤维区、心脏壁、雌雄生殖细胞、咽管等呈NOS的强阳性;腮管壁呈NOS阳性。结论 NO作为重要生物信使,直接参与钉螺神经肌肉运动、生殖和心血管调节等多种生命活动。  相似文献   
5.
目的 探讨三维记忆内固定系统(ATMFS)与重建钛板治疗髋臼骨折合并髋臼关节后脱位的临床疗效。方法 搜集2014年1月~2015年1月笔者医院收治的74例髋臼骨折合并髋臼关节后脱位患者为研究对象,根据所使用内固定物不同分为ATMFS组(34例)和重建钛板组(40例),对比两组临床疗效及预后情况。结果 ATMFS组手术时间为85.16±10.52min,明显少于重建钛板组手术时间102.72±14.26min,差异有统计学意义(P<0.05),ATMFS组术中出血量为836.74±136.15ml,明显少于重建钛板组术中出血量1003.47±216.38ml,差异有统计学意义(P<0.05);术后7天,采用X线标准对骨折复位进行评估,ATMFS组:优15例,良13例,一般4例,差2例,优良率为82.35%,重建钛板组:优15例,良14例,一般7例,差4例,优良率为72.50%,ATMFS组优良率高于重建钛板组,但差异无统计学意义(P>0.05);术后24个月末次随访,采用d''Aubigné髋关节评估系统进行临床疗效评定,ATMFS组优良率为91.18%,明显高于重建钛板组优良率72.50%,差异有统计学意义(P<0.05);随访6、12、24个月,ATMFS组Harris评分均明显高于重建钛板组,差异有统计学意义(P<0.05)。结论 ATMFS治疗髋臼骨折合并髋臼关节后脱位手术时间短,术中出血量较少,更有利于髋关节功能恢复。  相似文献   
6.
A study of maternal complications after elective Caesarean section in HIV-infected women was carried out from January 1999 to April 2001. The control group consisted of all the seronegative pregnant women who underwent the elective Caesarean section during the study period. The study group was divided into two subgroups. Subgroup 1 patients were given 600 mg zidovudine (ZDV) orally and 300 mg lamivudine (3TC) daily from 34 to 38 weeks' gestation. Subgroup 2 patients were given 600 mg ZDV orally daily from 34 to 38 weeks' gestation and 150 mg nevirapine orally on the morning of the Caesarean section day. In both groups, the elective Caesarean section was carried out at 38 weeks' gestation and ZDV syrup (2 mg/kg) was given orally to the newborn immediately in the operating theatre and then every 6 h for 4 weeks. No statistically significant differences in maternal complications were found between the HIV-infected and non HIV-infected women.  相似文献   
7.
目的探讨4种肝病相关自身抗体在肝功能异常患者血清中的阳性率及其诊断价值。方法间接免疫荧光法检测血清中ANA、SMA、AMA、抗LKM-I,根据荧光反应强弱判定结果。结果150例肝功异常患者(ALT〉50U/L)自身抗体阳性率为18.7%(28/150),其中抗核抗体(ANA)、抗平滑肌抗体(SMA)及抗线粒体抗体(AMA)的阳性率分别为12.7%(19/150)、6.7%(10)/150)和7.3%(11/150);未检出抗肝肾微粒体I型抗体(LKM-I);女性患者自身抗体的检出率明显高于男性患者(P〈0.05):病毒性肝炎标志物阴性组自身抗体检出率明显高于阳性组(P〈0.05)。结论自身抗体对自身免疫性肝病在诊断疾病、了解病程和观察疗效中具有很重要的价值,肝功能异常的非病毒性肝炎病人适合进行肝病相关自身抗体的检测。  相似文献   
8.
Neurodevelopmental disorders, such as attention‐deficit/hyperactivity disorder (ADHD), are often accompanied by disrupted cortical folding. We applied a quantitative sulcal pattern analysis technique using graph structures to study the atypical cortical folding at the lobar level in ADHD brains in this study. A total of 183 ADHD patients and 167 typical developmental controls matched according to age and gender were enrolled. We first constructed sulcal graphs at the brain lobar level and then investigated their similarity to the typical sulcal patterns. The within‐group variability and interhemispheric similarity in sulcal patterns were also compared between the ADHD and TDC groups. The results showed that, compared with controls, the left frontal, right parietal, and temporal lobes displayed altered similarities to the typical sulcal patterns in patients with ADHD. Moreover, the sulcal patterns in ADHD seem to be more heterogeneous than those in controls. The results also identified the disruption of the typical asymmetric sulcal patterns in the frontal lobe between the ADHD and control groups. Taken together, our results revealed the atypical sulcal pattern in boys with ADHD and provide new insights into the neuroanatomical mechanisms of ADHD.  相似文献   
9.
对异心叶桉提取物作室内杀钉螺实验观察,发现异心叶桉树叶和树枝中含有较高的杀钉螺成分。树叶水浸液浓度5000mg/L和10000mg/L室内浸杀钉螺72h死亡率分别为60.0%和87.5%;树叶乙醇提取物25mg/L浸杀钉螺72h死亡率达100%,在25±1℃时对钉螺浸杀48h和72h的LC50分别为16.0mg/L和12.2mg/L。鱼毒试验发现该提取物对斑马鱼毒性较低。认为桉树是具有较高杀灭钉螺价值的候选植物。  相似文献   
10.
Can adiponectin predict gestational diabetes?   总被引:5,自引:0,他引:5  
The aim of the present study was to evaluate whether adiponectin is a predictive factor for gestational diabetes mellitus (GDM) and is appropriate as a screening test for GDM. Three-hundred and fifty-nine women with singleton pregnancy and indications for GDM screening according to criteria of the American College of Obstetricians and Gynecologists were enrolled in the study between July 5, 2004 and March 11, 2005. After confirming gestational age (GA) and number of fetuses by ultrasound, all women underwent a 1-h glucose challenge test with 50 g glucose load (50-g GCT) between 21 and 27 weeks of GA. Blood samples for determination of adiponectin levels were also obtained on the same day. Subsequently, between 24 and 28 weeks of GA, the women underwent an oral glucose tolerance test with 100 g glucose load (100-g OGTT). The diagnosis of GDM was established when two or more of the following criteria were fulfilled: (1) fasting glucose >95 mg/dl; (2) 1-h glucose >180 mg/dl; (3) 2-h glucose >155 mg/dl; (4) 3-h glucose >140 mg/dl. Sixty women were diagnosed with GDM, a prevalence of 16.7%. There was no difference in age between the GDM and non-GDM groups. Pre-pregnancy and sampling-day body mass index (BMI), increase in weight and all blood glucose levels were greater in women with GDM than in those without (p < 0.05). Adiponectin concentrations were significantly negatively correlated with GA and plasma glucose levels of the GCT and each OGTT. Using logistic regression analyses, adiponectin, but not age, pre-pregnancy BMI and increase in weight, was demonstrated as an independent predictive factor for GDM. The area under the receiver-operator characteristic curve of adiponectin was significantly lower than that of the GCT [0.63 (95% confidence interval (CI) 0.53-0.67) vs. 0.73 (95% CI 0.71-0.80), p < 0.001]. At a cut-off value of 140 mg/dl of the 50-g GCT, the sensitivity and specificity of the test were 90% and 61%, respectively. The 50-g GCT could identify GDM in 54 (90%) out of 60 women. On the other hand, at an arbitrary cut-off value of 10 microg/ml for adiponectin, sensitivity of 91% and specificity of 31% were achieved. If this cut-off value was used for ruling in or out pregnant women for the GDM screening, 27% of all women could be eliminated from needing to perform an OGTT, with five women (8.3%) misclassified. In conclusion, this study demonstrated that adiponectin was an independent predictor for GDM. As for GDM screening, adiponectin was not as strong a predictor as GCT. However, with advantage of being less cumbersome, adiponectin could be used to rule out pregnant women at low risk of GDM.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号