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61.
目的 探讨芪苈强心胶囊联合尼可地尔对射血分数保留性心力衰竭患者心功能及细胞因子的影响。方法 连续入选2019年10月至2020年10月诊断为射血分数保留性心力衰竭的患者共90例,随机分为观察组(45例)与对照组(45例)。对照组给予常规抗心力衰竭药物加芪苈强心胶囊治疗,观察组在对照组治疗基础上,加用尼可地尔治疗。比较两组患者一般临床资料、细胞因子水平、心功能各项指标。随访1年患者心功能情况、细胞因子水平以及不良心脑血管事件(MACCEs)发生情况。结果 两组患者接受治疗1年后脑钠肽(BNP)、左室舒张末期内径、白细胞介素(IL)-1β、IL-6、肿瘤坏死因子-α(TNF-α)均降低,射血分数(EF)值较治疗前升高,差异有统计学意义(P<0.05)。组间对比发现,两组患者入院时基础BNP、细胞因子、超声心能指标(LVEF、左室舒张末期内径、左房内径)差异无统计学意义(P>0.05);接受治疗1年后观察组IL-1β、IL-6、TNF-α、BNP、左室舒张末期内径低于对照组,EF值高于对照组,差异有统计学意义(P<0.05)。随访1年对照组共有7例发生终点事件,观察组共有4... 相似文献
62.
利用指数衰减原理来抑制 x射线图像中小密度组织对骨骼边缘的影响 ,利用该方法很容易使用直方图原理提取出骨骼的边缘和内部结构变化的二值图 ,并有效地抑制了背景对骨骼边缘的影响 ,结合 canny算子的结果 ,可以有效地提取人体复杂结构中骨骼的边缘。 相似文献
63.
64.
利用在室温下的栅控恒压电晕充电后经不同强度紫外线辐照的表面电位测量,研究了紫外线对聚四氟乙烯(polytetrafluoroethylene,PTFE)多孔膜、聚四氟乙烯非多孔膜驻极体电荷储存稳定性的影响,探讨了两种聚四氟乙烯驻极体医疗产品使用紫外消毒方法的可行性.结果:(1)在常温条件下,紫外线辐照对两种聚四氟乙烯驻极体的电荷储存稳定性的影响不大;(2)聚四氟乙烯多孔膜驻极体的电荷储存能力随环境湿度的提高而略有下降;(3)聚四氟乙烯医用驻极体产品可采用紫外消毒法消毒. 相似文献
65.
Development of a Western Blot Assay for Detection of Antibodies against Coronavirus Causing Severe Acute Respiratory Syndrome
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Qigai He Kooi Hoong Chong Hiok Hee Chng Bernard Leung Ai Ee Ling Ting Wei Shzu-Wei Chan Eng Eong Ooi Jimmy Kwang 《Clinical and Vaccine Immunology : CVI》2004,11(2):417-422
To identify a major antigenic determinant for use in the development of a rapid serological diagnostic test for severe acute respiratory syndrome (SARS) coronavirus infection and to study the immune response during SARS coronavirus infection in humans, we cloned the full length and six truncated fragments of the nucleocapsid gene, expressed them, and purified them as glutathione S-transferase-tagged recombinant proteins. The reactivities of the recombinant proteins to a panel of antibodies containing 33 SARS coronavirus-positive sera and 66 negative sera and to antibodies against other animal coronaviruses were screened. A truncated 195-amino-acid fragment from the C terminus of the nucleocapsid protein (N195) was identified that had a strong ability to detect antibodies against SARS coronavirus. No cross-reaction was found between the N195 protein and antibodies against chicken, pig, and canine coronaviruses. The N195 protein was used to develop a Western blot assay to detect antibodies against SARS coronavirus in 274 clinically blinded samples. The specificity and sensitivity of this test were 98.3 and 90.9%, respectively. The correlation between our Western blotting assay and an immunofluorescence assay (IFA) was also analyzed. The results of our Western blot assay and IFA for the detection of SARS coronavirus-positive sera were the same. Thus, the N195 protein was identified as a suitable protein to be used as an antigen in Western blot and other possible assays for the detection of SARS coronavirus infection. 相似文献
66.
Ontogenetic transition in fetal wound transforming growth factor-beta regulation correlates with collagen organization 总被引:2,自引:0,他引:2
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Soo C Beanes SR Hu FY Zhang X Dang C Chang G Wang Y Nishimura I Freymiller E Longaker MT Lorenz HP Ting K 《The American journal of pathology》2003,163(6):2459-2476
Fetal rat skin transitions from scarless fetal-type repair to adult-type repair with scar between day 16 (E16) and day 18 (E18) of gestation (term = 21.5 days). Deficient transforming growth factor (TGF)-beta 1 and -beta 2 injury response has been proposed as a mechanism for scarless fetal-type repair. However, previous fetal studies have inconsistently reported the degree of TGF-beta induction after injury. To minimize developmental variables in fetal versus adult TGF-beta regulation, we narrowed our study to wounded fetal animals. We hypothesize that TGF-beta ligand and receptor expression will be differentially regulated during the transition from early gestation (E16) wounds manifesting scarless fetal-type repair to late gestation (E19) wounds manifesting adult-type repair with scar. In this study, decreased and rapidly cleared TGF-beta 1 and -beta 2 expression accompanied by increased and prolonged TGF-beta 3 levels in wounded E16 animals correlated with organized collagen deposition. In contrast, increased and prolonged TGF-beta 1 and -beta 2 expression accompanied by decreased and delayed TGF-beta 3 expression in wounded E19 animals correlated with disorganized collagen architecture. Similarly, expression of TGF-beta receptors type I and II were also increased or prolonged in E19 animals. Our results implicate increased TGF-beta 1, -beta 2, and decreased TGF-beta 3 expression, as well as increased type I and II receptor expression in late gestation fetal scar formation. 相似文献
67.
Plurihormonal pituitary adenomas: immunostaining of all pituitary hormones is mandatory for correct classification 总被引:4,自引:0,他引:4
AIMS: We studied the clinicopathological characteristics of plurihormonal pituitary adenomas. METHODS AND RESULTS: The study material included 167 plurihormonal adenomas, which consisted of 31% of the surgically removed pituitary adenomas that we collected during a 12-year period. The mean age of patients with plurihormonal adenoma was 45.7 years (range 13-75 years). There were 86 men and 81 women. All tumours were fully classified by immunohistochemical staining for seven pituitary hormones or subunits. Thirty immunohistochemical subtypes of plurihormonal adenomas were recognized. Hormonal symptoms were present in 70% of patients, while serum hormonal levels were increased in 89% of patients. Most patients had symptoms related to only one of the hormones and only 7% of patients had symptoms related to two hormones. The most common hormonal symptom was acromegaly (50%); symptoms related to hyperprolactinaemia ranked second (20%). Double immunostaining of all the possible combinations of the hormones was performed in 30 selected tumours, and they all showed mixtures of hormones in individual adenoma cells in any hormonal combinations studied. The latter finding supported the view that plurihormonal adenomas are monomorphous adenomas. CONCLUSIONS: Plurihormonal adenomas are common pituitary adenomas. Immunohistochemical staining of all pituitary hormones is mandatory for correct classification. 相似文献
68.
应用肿瘤基因芯片筛选早期肺鳞癌相关基因 总被引:1,自引:2,他引:1
目的: 研究人早期肺鳞癌发生相关基因表达谱, 探讨肺鳞癌发生的分子机制。方法:选取人早期肺鳞癌组织以及相应正常组织,提取RNA, 与含480个与肿瘤相关基因的芯片杂交, 结果经SuperArray Image 软件分析后比较两种组织中的差异表达基因。结果:共筛查出差异表达基因192 条,其中表达上调基因127 条, 下调基因65条; 按照基因功能可分为运输载体、代谢相关基因、细胞信号转导分子、细胞骨架、转录调控因子基因。结论:基因芯片可用于早期肺鳞癌相关基因表达谱的筛查,可为明确早期肺鳞癌发生机制提供重要参考。 相似文献
69.
In an eosinophilic population of 47 boys of the same age, a large proportion (92%) were helminth infested or atopic, or both, compared with 36% of 36 controls. The methods used to detect these conditions were not costly or elaborate, except for the radioallergosorbent test, which was used to measure concentrations of circulating IgE antibodies to atopic allergens. It is suggested that an economical approach to detect helminthiasis and atopy in cases of eosinophilia is adopted using the methods employed here, with skin prick tests replacing the radioallergosorbent test. 相似文献
70.