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61.
Plasma interleukin-1 (IL-1) activity is modulated in part through the simultaneous appearance of several inhibitors of IL-1 action, including interleukin-1 receptor antagonist (IL-1ra) and the soluble IL-1 type II receptor (IL-1RII). However, little is known concerning the plasma appearance of these inhibitors in patients following operative trauma or those with sepsis syndrome. In the present report, plasma IL-1beta, IL-1ra, and soluble IL-1RI and IL-1RII concentrations were evaluated in 118 patients with sepsis syndrome or after elective operative trauma. Plasma concentrations of IL-1ra increased significantly following elective operative repair of thoraco-abdominal and abdominal aortic aneurysms, and after bowel resection for inflammatory bowel disease, but did not increase after laparoscopic cholecystectomy. Plasma IL-1ra levels were also elevated in patients with sepsis syndrome. In contrast, soluble IL-1RII levels were only increased in patients after operative repair of thoraco-abdominal aortic aneurysms and in sepsis syndrome, whereas concentrations were unaffected by the other more modest surgical procedures. Plasma IL-1RI concentrations decreased in all postoperative patients in the first 24 hours after surgery. We conclude that both plasma IL-1ra and soluble IL-1RII concentrations often increase in sepsis and following some operative trauma. Less severe operative trauma increases the plasma concentration of only IL- 1ra, whereas both IL-1ra and soluble IL-1RII are increased in patients with sepsis syndrome or following thoraco-abdominal aneurysm repair.  相似文献   
62.
Parker  RI; Gralnick  HR 《Blood》1989,74(6):2016-2021
Platelets contain a pool of endogenous platelet-von Willebrand factor (vWF) that becomes expressed on the platelet surface when platelets are stimulated by a variety of agonists. Maximal platelet-vWF expression occurs in concert with platelet alpha-granule secretion. Aspirin (ASA) is known to impair platelet activation and alpha-granule secretion by irreversible inhibition of platelet cyclo-oxygenase. We studied native and ASA-treated platelets for their ability to mobilize and to express platelet-vWF in response to adenosine diphosphate (ADP) or thrombin. We found that each agonist was effective in promoting increased platelet- vWF surface expression on native and ASA-treated platelets. ASA-treated platelets responded identically to native platelets to low (0.01 U/mL) and high (1.0 U/mL) concentrations of thrombin, while the ADP-induced increase in ASA-treated platelets was only 50% to 60% of that for control platelets. Measurement of secreted platelet-vWF and beta- thromboglobulin indicated that the increase seen with ADP was largely independent of alpha-granule secretion. Using monoclonal antibodies (MoAbs) against the platelet glycoproteins (GP) IIb/IIIa and Ib (MoAbs 10E5 and 6D1, respectively), we demonstrated that the ADP-induced increase in platelet-vWF expression on control platelets primarily involved the binding of secreted platelet-vWF to the platelet GPIIb/IIIa. In contrast, the increase in platelet-vWF that occurred following ADP stimulation of ASA-treated platelets was largely insensitive to GPIIb/IIIa blockade. No effect of GPIb blockade in platelet-vWf expression was noted for either control or ASA-treated platelets. When platelet shape change was prevented by the addition of cytochalasin D, ADP-induced platelet-vWf surface expression on ASA- treated platelets was reduced by more than 80%. Our data indicate that platelets in which the cyclooxygenase pathway is blocked by the action of aspirin can increase surface expression of platelet-vWf as a consequence of platelet shape change. We speculate that this process exposes platelet-vWf bound to GPIIb/IIIa, or possibly GPIb, within the surface connected canalicular system.  相似文献   
63.
目的:比较经腹膜后精索静脉高位结扎术与腹腔镜下改良Palomo术两种方法治疗精索静脉曲张的效果。方法:收集我院1994年1月~2008年11月行手术治疗并获得随访的Ⅱ度及以上的精索静脉曲张患者305例,根据手术分为两组:A组263例行经腹膜后精索静脉高位结扎术;B组42例行腹腔镜下改良palomo术。对比观察两组术后阴囊水肿、辜丸萎缩、复发等,近、远期并发症及精液质量改善和生育情况。结果:术后阴囊水肿发生率B组为16.7%,A组为2.3%,两组比较差异有统计学意义(P〈0.05);术后3个月睾丸萎缩发生率B组为9.5%,A组为1.1%,两组比较差异有统计学意义(P〈0.05);≤30岁患者A组术后6个月精液质量提高率为82%,高于B组术后6个月的74.2%(P〈0.05);两组≤30岁患者术后1~2年内配偶自然怀孕率为69.5%、55.6%,A组高于B组(P〈0.05)。结论:经腹膜后精索静脉高位结扎术术式简单易掌握且术后阴囊水肿和睾丸萎缩发生率低,术后精液质量提高率和术后1~2年内配偶自然怀孕率高,值得广泛推广。  相似文献   
64.

Background and purpose:

Muscarinic stimulation increases myofilament Ca2+ sensitivity with no apparent inotropic response in normal rat myocardium. Increased myofilament Ca2+ sensitivity is a molecular mechanism promoting increased contractility in failing cardiac tissue. Thus, muscarinic receptor activation could elicit inotropic responses in ventricular myocardium from rats with heart failure, through increasing phosphorylation of myosin light chain (MLC).

Experimental approach:

Contractile force was measured in left ventricular papillary muscles from male Wistar rats, 6 weeks after left coronary artery ligation or sham surgery. Muscles were also frozen, and MLC-2 phosphorylation level was quantified.

Key results:

Carbachol (10 µmol·L−1) evoked a positive inotropic response only in muscles from rats with heart failure approximating 36% of that elicited by 1 µmol·L−1 isoproterenol (20 ± 1.5% and 56 ± 6.1% above basal respectively). Carbachol-evoked inotropic responses did not correlate with infarction size but did correlate with increased left ventricular end diastolic pressure, heart weight/body weight ratio and lung weight, primary indicators of the severity of heart failure. Only muscarinic receptor antagonists selective for M2 receptors antagonized carbachol-mediated inotropic effects with the expected potency. Carbachol-evoked inotropic responses and increase in phosphorylated MLC-2 were attenuated by MLC kinase (ML-9) and Rho-kinase inhibition (Y-27632), and inotropic responses were abolished by Pertussis toxin pretreatment.

Conclusion and implications:

In failing ventricular muscle, muscarinic receptor activation, most likely via M2 receptors, provides inotropic support by increasing MLC phosphorylation and consequently, myofilament Ca2+ sensitivity. Enhancement of myofilament Ca2+ sensitivity, representing a less energy-demanding mechanism of inotropic support may be particularly advantageous in failing hearts.  相似文献   
65.
66.
目的:探讨尿液微量白蛋白(UMA)检测在糖尿病肾病早期诊断中的价值。方法:检测82例2型糖尿病患者的尿液微量白蛋白,并与58例健康体检者检测结果进行对比分析。结果:糖尿病组UMA阳性率明显高于健康体检组,且差异有显著性。结论:尿微量白蛋白的出现常反映肾脏结构与功能已经轻度受损,测定UMA有助于糖尿病肾病的早期诊断和早期预防。  相似文献   
67.
目的:研究蒙古族、汉族胃癌患者血清胃蛋白酶原(Pepsinogen PG)水平,探讨血清PG的地域和民族特征及规律,提供有价值的临床流行病学资料。方法:选择2008年10月~2009年10月在包头市肿瘤医院经内镜检查和病理学确诊的胃癌患者68例(3代人均为同一民族,蒙古族30例,汉族38例),选择42例健康体检者做正常对照组。应用酶联免疫方法进行血清PGⅠ、PGⅡ的检测,并计算PGⅠ/PGⅡ比值。结果:蒙古族、汉族胃癌组血清PGⅠ及PGⅠ/PGⅡ值明显低于正常对照组,具有显著性差异(P〈0.05),各组血清PGⅡ水平之间无显著性差异(P〉0.05);蒙古族胃癌组血清PGⅠ及PGⅠ/PGⅡ值低于汉族胃癌组,具有显著性差异(P〈0.05),两组血清PGⅡ水平之间无显著性差异(P〉0.05)。结论:蒙古族、汉族胃癌患者血清PGⅠ及PGⅠ/PGⅡ值较正常对照组降低,提示血清PGⅠ及PGⅠ/PGⅡ值降低有助于胃癌的诊断,可以作为地区人群筛查和辅助诊断胃癌的一项血清学指标;蒙古族胃癌患者血清PGⅠ及PGⅠ/PGⅡ值低于汉族胃癌患者,提示血清PG水平在不同种族人群中存在着差异。  相似文献   
68.
Seo SI, Song SY, Kang MR, Kim MS, Oh JE, Kim YR, Lee JY, Yoo NJ, Lee SH. Immunohistochemical analysis of NF‐κB signaling proteins IKKε, p50/p105, p52/p100 and RelA in prostate cancers. APMIS 2009; 117:623–8. Activation of nuclear factor‐kappa B (NF‐κB) signaling is considered an important mechanism in the development of prostate cancers. A recent study revealed that IκB kinase epsilon (IKKε), an activator of NF‐κB, was overexpressed in breast cancers and acted as an oncogene. Expression of NF‐κB members has been reported in prostate cancer tissues, but expression of IKKε has not yet been studied in prostate cancers. In this study, we attempted to explore as to whether expressions of IKKε and NF‐κB members p50/105, p52/p100 and RelA are altered in prostate cancers. We analyzed the expression of IKKε, p50/105, p52/p100 and RelA in 107 prostate adenocarcinoma tissues by immunohistochemistry using a tissue microarray (TMA) method. In the TMA, IKKε is expressed in basal cells, but not in alveolar cells in normal prostate glands. IKKε is expressed in 60.0% of prostate intraepithelial neoplasm (PIN) and 70.1% of the prostate cancers in the cytoplasm. Nuclear immunostainings of NF‐κB members p50/105, p52/p100 and RelA, which are considered activation of NF‐κB signaling, were observed respectively in 28.0%, 18.7% and 37.4% of the cancers. Nuclear staining was detected neither in normal alveolar cells nor in PIN. However, none of the expression of p50/105 nor p52/p100 nor RelA nor IKKε was associated with pathologic characteristics, including size of the cancers, age, Gleason score and stage. The increased cytoplasmic expression of IKKε as well as the increased nuclear expressions of p50/105, p52/p100 and RelA in the prostate cancers compared to normal alveolar cells suggested that overexpression of these proteins may be related to activation of the NF‐κB pathway and might play a role in tumorigenesis of prostate cancers.  相似文献   
69.
70.
This study presents physical fitness data on two indigenous Siberian populations, the Evenki and Keto. The Canadian Aerobic Test of Fitness (CATF) was utilized to provide estimates of maximal oxygen consumption (V?O2 max) for a sample of 44 subjects (30 males, 14 females) as baseline data for further studies on changing fitness levels and the health problems associated with acculturation. Estimates of V?O2 max average 46.2 ml kg?1 min?1 for males and 33.9 ml kg?1 min?1 for females. These values are comparable to those previously reported for other semisubsistence, cold adapted populations. The Siberian groups are below the Canadian norms in the 15–19 year age range, and thereafter track at about the 50th percentile throughout adulthood. This suggests that the cardiorespiratory systems of adult Evenki and Keto are functionally comparable to the average adult Canadian. © 1994 Wiley-Liss, Inc.  相似文献   
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