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41.
The aim of the present study was to elucidate if the potentiating effect of neuropeptide Y on various vasoactive agents in vitro is (1) altered in mesenteric arteries from rats with congestive heart failure and (2) mediated by the neuropeptide Y Y1 receptor. The direct vascular effects of neuropeptide Y and its modulating effects on the contractions induced by endothelin-1-, noradrenaline-, 5-hydroxytryptamine (5-HT)-, U46619-(9, 11-dideoxy-11, 9-epoxymethano-prostaglandin F2) and ATP, and acetylcholine-induced dilatations were studied in the presence and absence of the neuropeptide Y Y1 antagonist, BIBP3226 (BIBP3226{(R)-N2-(diphenylacetyl)-N-[(4-hydroxyphenyl)methyl]- -arginine-amide}). Neuropeptide Y, per se, had no vasoactive effect in the arteries. The potency of endothelin-1 was significantly decreased in congestive heart failure rats. Neuropeptide Y and neuropeptide Y-(13–36) potentiated the endothelin-1-induced contraction in congestive heart failure mesenteric arteries. In 20% of the congestive heart failure rats, sarafotoxin 6c induced a contraction of 31±4%. Neuropeptide Y also potentiated U46619- and noradrenaline-induced contractions but not 5-HT-induced contractions in congestive heart failure arteries. In sham-operated animals neuropeptide Y potentiated noradrenaline- and 5-HT-induced contractions. These potentiations were inhibited by BIBP3226. Acetylcholine induced an equipotent relaxation in both groups which was unaffected by neuropeptide Y. In conclusion, neuropeptide Y responses are altered in congestive heart failure rats. The potentiating effect differs between vasoactive substances. Neuropeptide Y Y1 and non-neuropeptide Y1 receptors are involved.  相似文献   
42.
目的鉴于MRI对组织的高分辨性能,利用该图像观察颈椎综合征患者的椎管外组织的病理状况.方法54例患者,其中男30例,女24例,分为2组.观察组44例颈椎综合征患者,对照组10例颈部外伤和三叉神经痛患者.通过常规的MRI矢状位及横轴位颈椎图像,比较两组软组织增生情况.结果与结论在颈椎综合征MRI的颈椎及上段胸椎棘突后侧,均可观察到不同程度的慢性纤维性变化,与对照组比较,有可比性.提示临床上颈椎综合征多与颈肩区筋膜炎、棘突炎相关,属于无菌性炎症,其慢性阶段,局部发生了纤维增生性改变.建议在观察分析此种病症的颈椎骨质及椎间盘改变的同时,宜重视棘突后侧的纤维性变化,有利于病理病因的研究.  相似文献   
43.
脚压测量用传感器   总被引:1,自引:0,他引:1  
本文讨论了用于脚压测量的四类压力传感器,电阻式传感器、压电式传感器,光电式传感器,电容式传感器介绍了其结构、原理和特点,并分析了几种典型的测量接口电路。  相似文献   
44.
45.
A fastidious gram-negative bacterium was isolated from the blood of a 37-year-old man who had insidious endocarditis with a sudden rupture of a cerebral aneurysm. Characterization of the organism through phylogenetic and phenotypic analyses revealed a novel species of Cardiobacterium, for which the name Cardiobacterium valvarum sp. nov. is proposed. C. valvarum will supplement the current sole species Cardiobacterium hominis, a known cause of endocarditis. Surgeries and antibiotic treatment cured the patient's infection and associated complications. During cardiac surgery, a congenital bicuspid aortic valve was found to be the predisposing factor for his endocarditis.  相似文献   
46.
多种金属离子与单宁酸反应媒染微血管的对比研究   总被引:2,自引:0,他引:2  
目的 镜下观察单宁酸与金属盐溶液中Ca2 + 、Au+ 、Ag+ 、Pb2 + 、Cu2 + 、Al3 + 、U6+ 、K+ 联用显示大脑微血管的效果。方法 用单宁酸媒染固定液灌流大鼠 ,取脑切片 ,入氯化钙、氯化金、硝酸银、硝酸铅、硫酸铜、硫酸铝钾、醋酸双氧铀、高锰酸钾和重铬酸钾等溶液中呈色。结果 单宁酸与Ca2 + 、Cu2 + 、Ag+ 、Al3 + 结合显示血管清晰 ,与Au+ 、U6+ 、Pb2 + 、K+ 联用媒染血管效果欠佳。结论 含Ca2 + 、Cu2 + 、Ag+ 、Al3 + 的金属盐类可替代氯化铁媒染微血管 ,氯化金、醋酸双氧铀、硝酸铅、重铬酸钾和高锰酸钾不宜与单宁酸联用来显示血管  相似文献   
47.
48.
Brachydactyly type A (BDA) is defined as short middle phalanges of the affected digits and is subdivided into four types (BDA1‐4). To date, the molecular cause is unknown. However, there is some evidence that pathogenic variants of HOXD13 could be associated with BDA3 and BDA4. Here, we report a Chinese autosomal dominant BDA3 pedigree with a novel HOXD13 mutation. The affected individuals presented with an obviously shorter fifth middle phalanx. The radial side of the middle phalanx was shorter than the ulnar side, and the terminal phalanx of the fifth finger inclined radially and formed classical clinodactyly. Interestingly, the index finger was normal. The initial diagnosis was BDA3. However, the distal third and fourth middle phalanges were also slightly affected, resulting in mild radial clinodactyly. Both feet showed shortening of the middle phalanges, which were fused to the distal phalanges of the second to the fifth toes, as reported in BDA4. Therefore, this pedigree had combined BDA3 and atypical BDA4. By direct sequencing, a 13 bp deletion within exon 1 of HOXD13 (NM_000523.4: c.708_720del13; NP_000514.2: p.Gly237fs) was identified. The 13 bp deletion resulted in a frameshift and premature termination of HOXD13. This study provides further evidences that variants in HOXD13 cause BDA3‐BDA4 phenotypes.  相似文献   
49.
The serum kinetics of preS1 and preS2 antigens has been evaluated in 38 serial samples from eight patients with chronic active (CAH) or chronic persistent (CPH) hepatitis, followed for 2–7 years (mean 4.4 years) in whom liver biopsy was performed at intervals, and in 46 samples from ten asymptomatic HBsAg carriers followed for 4–5 years (mean 4.6 years). Four patterns of preS behaviour have been observed: (1) persistently positive preS1 and preS2; (2) disappearance of preS2; (3) disappearance of both preS1 and preS2; and (4) persistently negative preS1 and preS2. Pattern 4 has been observed exclusively among healthy carriers, while seven out of eight chronic patients exhibited either pattern 1 or 2. Among the chronic patients, preS2 disappearance was accompanied or followed by alanine aminotransferase (ALT) normalization. The correlation of preS antigens with conventional viral replication markers showed that 100% of hepatitis B virus (HBV)-DNA-positive and 86.6% of HBeAg-positive sera were preS1/preS2 positive, while 61% of HBV-DNA-negative and 64% of HBeAg-negative sera were preS1/preS2 negative. Our data suggest that continuous monitoring of preS antigens in follow-up sera will allow for an improved prognostic evaluation of chronic HBV infection.  相似文献   
50.
A method was developed to compare the lymphocytic infiltrates in regressing vs. progressing experimental mouse tumors using a model for human papillomavirus-16 (HPV-16) oncoprotein-linked cancer. Tumor cells mixed with matrigel, composed of natural matrix substances that provide a basement membrane structure for adherent cells, were inoculated into mice vaccinated with an efficacious vaccine to the E7 oncoprotein or a vaccine to a control antigen. The tumor cells remained within the solidified gel and recruited a cellular infiltrate that could readily be analyzed upon removal of the gelatinous mass containing progressing or regressing tumors. The results show that tumors recruit activated CD8(+) T cells regardless of their antigen specificity. In regressing tumors expressing an appropriate target antigen for the vaccine-induced CD8(+) T cells, a strong increase of the tumor antigen-specific T cell population was observed over time. Progressing tumors that lacked the target antigen for the activated CD8(+) T cell population did not show this selective enrichment.  相似文献   
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