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31.
OBJECTIVE: To determine the effects of recombinant equine IL-1beta and a number of antiinflammatory compounds on the expression and activity of inducible nitric oxide synthase (iNOS) in cultured equine chondrocytes. DESIGN: RT-PCR methods were used to amplify a portion of the equine iNOS message to prepare an RNA probe. Northern blot analysis was used to quantify the expression of iNOS in first passage cultures of equine articular chondrocytes propagated in the presence or absence of recombinant equine interleukin-1beta (reIL-1beta), dexamethasone (DEX), polysulfated glycosaminoglycan (PSGAG), hyaluronan (HA), and phenylbutazone (PBZ), each at concentrations of 10 and 100 microg/ml. Nitrite concentrations in conditioned media of similarly treated cells were used to quantify iNOS activity. RESULTS: Recombinant equine IL-1beta increased the expression of iNOS in a dose-dependent manner. This result was paralleled by an increased concentration of nitrite in the culture media of reIL-1beta-treated cells. DEX and PSGAG significantly reduced iNOS gene expression and media supernatant nitrite concentrations in cytokine-stimulated cultures. HA and PBZ had no consistent effect on the expression of iNOS and did not significantly influence nitrite content of conditioned media. CONCLUSIONS: NO is considered an important mediator in the pathophysiologic processes of arthritis and an inducible NOS is expressed by equine chondrocytes. Pre-translational regulation of the iNOS gene by DEX and PSGAG appears to contribute to the cartilage-sparing properties of these compounds.  相似文献   
32.
Five out of 12 physically healthy patients with depression undergoing a tyramine pressor test developed cardiac arrhythmias. These arrhythmias occurred in drug-free patients in three out of 12 infusions following as little as 0.03 mg/kg of tyramine and after moclobemide, a reversible inhibitor of monoamine oxidase-A, in four out of 14 tyramine infusions with as little as 0.04 mg/kg of tyramine. The arrhythmias seen were independent of patient's age and occurred both before and after 30 mmHg elevations in systolic blood pressure. Electrocardiographic abnormalities and arrhythmias seen were a loss of p waves, sinus tachycardia, frequent atrial ectopic beats, atrial premature beats, Wenckebach phenomenon, junctional rhythm, ventricular ectopics, varying QRS configurations, and ventricular bigeminy. Tyramine, both oral and intravenous, caused similar reproducible changes in dogs, though not in rats, mice or guinea pigs. Practical implications are that tyramine pressor testing in humans should be performed cautiously and only with adequate cardiac monitoring and resuscitation facilities at hand. These findings suggest that a normal dietary component can induce serious cardiac arrhythmias, and that a low-tyramine diet may be of value for patients who are susceptible to cardiac arrhythmias.  相似文献   
33.
随着医院业务不断发展,其信息系统应用范围也日渐扩大,医院信息系统是医院的主要经济支柱和命脉,因此保障医院信息系统运行安全非常重要.本文分别从划分 VLAN、使用组策略、病毒服务器、网管软件、 VNC软件的使用五个策略对保障 HIS系统的安全运行进行探讨.  相似文献   
34.
Background: Anesthesiologist-directed preoperative medicine clinics are used to prepare patients for the administration of anesthesia and surgery. Studies have shown that such a clinic reduces preoperative testing and consults, but few studies have examined the impact of the clinic on the day of surgery. The authors tested whether a visit to an anesthesia preoperative medicine clinic (APMC) would reduce day-of-surgery case cancellations and/or case delays.

Methods: The authors conducted a retrospective chart review of all surgical cases during a 6-month period at the University of Chicago Hospitals. Case cancellations and rates of first-start case delay over the 6-month period were cross-referenced with a database of APMC attendees in both the general operating rooms and the same-day surgery suite. The impact of a clinic visit on case cancellation and delay in both sites were analyzed separately.

Results: A total of 6,524 eligible cases were included. In the same-day surgery suite, 98 of 1,164 (8.4%) APMC-evaluated patients were cancelled, as compared with 366 of 2,252 (16.2%) in the non-APMC group (P < 0.001). In the general operating rooms, 87 of 1,631 (5.3%) APMC-evaluated patients were cancelled, as compared with 192 of 1,477 (13.0%) patients without a clinic visit (P < 0.001). For both operating areas, APMC patients had a significantly earlier room entry time than patients not evaluated in the APMC.  相似文献   

35.
Carcinoids of the pancreas are exceedingly rare tumors that orieinate from the enterochromaffin cells of the gastroenteropancreatic neuroendocrine system. According to a recent report,1 pancreatic carcinoids are found in only 0.58% (79/13 715 cases) of the entire carcinoid group. Todate, very limited information regarding the detection and diagnosis of this entity has been reported in the available literature. Although pancreatic carcinoid tumors grow.  相似文献   
36.
In 1998, an epithermal neutron test beam was designed and constructed at the Tsing Hua Open-Pool Reactor (THOR) for the purpose of preliminary dosimetric experiments in boron neutron capture therapy (BNCT). A new epithermal neutron beam was designed at this facility, and is currently under construction, with clinical trials targeted in late 2004. Depth dose-rate distributions for the THOR BNCT test beam have been measured by means of activation foil and dual ion chamber techniques. Neutron and structure-induced gamma spectra measured at the test beam exit were configured into a source function for the Monte Carlo-based treatment planning code NCTPlan. Dose-rate scaling factors (DRSFs) were determined to normalize computationally derived dose-rate distributions with experimental measurements in corresponding mathematical and physical phantoms, and to thus enable accurate treatment planning using the NCTPlan code. A similar approach will be implemented in characterizing the new THOR epithermal beam in preparation for clinical studies. This paper reports the in-phantom calculated and experimental dosimetry comparisons and derived DRSFs obtained with the THOR test beam.  相似文献   
37.
浙江省某乡村慢性肾脏病的流行病学研究   总被引:14,自引:1,他引:13  
目的 研究我国南方某农村人群中慢性肾脏病(CKD)的患病率及相关因素。方法 对浙江省东阳市某乡村18岁以上的常住居民慢性肾脏病情况及相关因素进行调查和检测。结果 获得完整资料的居民占该村18岁以上自然人口的76.2%。将该村自然人口按年龄性别构成校正后,白蛋白尿发生率为10.4%;肾小球滤过率〈60ml·min^-1·(1.73m^2)^-1的发生率为3.0%;血尿发生率为1.4%。本研究中40岁以上调查对象与北京市某社区及NHANESⅢ中40岁以上调查对象相比,高血压及糖尿病的患病率较低,白蛋白尿和肾功能下降的发生率介于2者之间。多因素Logistic回归提示,年龄增加10岁、糖代谢异常及收缩压水平与白蛋白尿的发生独立相关;女性、年龄增加10岁、高尿酸血症与肾功能下降独立相关;年龄增加10岁及吸烟与血尿独立相关。结论 在该经济快速发展的南方乡村,CKD的疾病谱和相关因素已经与我国大城市和发达国家类似。此外,该人群可能另有导致CKD高发的特殊原因,需进一步研究。  相似文献   
38.
下前牙桩核冠三维有限元模型的建立   总被引:1,自引:0,他引:1  
目的:建立桩核冠修复后的下颌中切牙及其牙周支持组织的三维有限元模型。方法:利用薄层CT技术、UG软件与ALGOR软件相结合,对层厚为0.2mm的CT断层影像进行分析处理。结果:模型共有单元45153个,节点27763个,可以根据要求任意旋转、缩放、透视、剖开,进行多种方式观察;并可以按照不同研究目的,对模型进行修改和调整,来模拟不同程度牙槽骨吸收、联冠修复以及各种约束和加载条件下前牙的力学反应。结论:利用薄层CT扫描技术、UG自由曲面功能以及ALGOR软件相结合建立的三维有限元模型,能较精确地模拟临床口腔实际情况,为进一步研究下颌前牙不同牙周情况下的修复奠定了良好的基础。  相似文献   
39.
眼轴线后部眶容积增大与眼球内陷比值的测定研究   总被引:1,自引:0,他引:1  
目的:通过测量眼眶爆裂性骨折伴有眼眶扩大患者的后部眼眶容积、观察眼球内陷出现的时间及程度,研究后部眶容积扩大与眼球内陷的关系比值,为病情预测和眶内填充手术提供比较精确的参考数据。方法:将96例患者按发病时间分为早期病例组(60例、受伤时间1周以内)和晚期病例组(36例、受伤时间3个月以上),早期组除进行后部眼眶容积测量外,分别于1周、2周、3周测定眼球突出度(相差>1mm为阳性),记录眼球内陷出现时间,用卡方检验进行统计学分析;晚期组测量后部眶容积增大值和眼球内陷量,对其相关性采用Pearson统计方法进行统计学分析,并得出回归方程及相关系数。结果:早期组60例患者中,(58.33%)例患者在1周内出现眼球内陷,4(880%)例在2周内出现内陷,3周时有5(388.33%)例呈现出内陷;2周时出现眼球内陷的例数与1周时有显著性差异(χ2=62.484,P<0.001),2周时出现眼球内陷例数与3周时无差异(χ2=1.563,P>0.05),1周时出现眼球内陷例数与3周时有显著差异(χ2=76.885,P<0.001),后部眶容积增大与眼球内陷的比值约为1.0,两者之间呈正相关(r=0.994,P<0.001),即后部眶容积每增加1ml,产生1.0mm的眼球内陷。结论:眼球内陷通常于伤后2周~3周出现,3个月时趋向稳定;后部眶容积增大与眼球内陷产生比值为1.0,呈正相关;后部眶容积扩大与眼球内陷比值可预测发生眼球内陷的可能性和程度,为手术矫正眼球内陷提供可靠、精确的参考,具有十分重要的临床指导意义。  相似文献   
40.
The role of MHC class Ⅱ transactivator (CⅡTA) in constitutive or IFN-γ inducib|e expression of HLA molecules in human malignant hematological cell lines was investigated. The expression of HLA molecules and CⅡTA protein was detected by Western blot, immunohistochemistry and flow cytometry. The expression of CⅡTA gene was determined by RT-PCR. The capability of peripheral blood T cell reaction stimulated by tumor cells was monitored by mixed lymphocyte reaction. It was found that the HLA Ⅱ-positive tumor cells expressed the CⅡTA quite well, andthe expression of HLA Ⅰ+Ⅱ was increased in the tumor cells with constitutive or inducible expression of CⅡTA after induced by IFN-γ. The tumor cells which did not express CⅡTA after in-duced by IFN-γ were not response to the expression of HLA Ⅱ promoted by IFN-γ. It suggests a correlation between the inability of some malignant hematological cell lines in response to IFN-γ for HLA expression and the deficiency in the inducible expression of CⅡTA, indicating CⅡTA might take part in the regu|ation of HLA Ⅰ+Ⅱ expression in the tumor cells, which might p|ay an important role in tumor immunologic escape.  相似文献   
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