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21.
Delgado  M; Garrido  E; Martinez  C; Leceta  J; Gomariz  RP 《Blood》1996,87(12):5152-5161
In the present study, the effects of vasoactive intestinal peptide (VIP) and the pituitary adenylate cyclase-activating polypeptides, PACAP27 and PACAP38, in a concentration range from 10(-13) to 10(-6) mol/L were studied in vitro on the spontaneous and dexamethasone (DEX)- induced apoptosis in rat thymocytes. The results show that VIP and both PACAPs inhibit significantly and in a similar way the DNA fragmentation characteristic of glucocorticoid-induced apoptosis and increase the cell survival of thymocytes, with a maximal effect observed at 10(-8) to 10(-9) mol/L. This study showed the ability of the VIP-receptor (VIP- R) antagonist [N-Ac-Tyr1,D-Phe2]-GRF(1-29) amide to partially reverse the inhibitory effect of VIP and both PACAPs on DEX-induced apoptosis, providing evidence for a specific VIP1-R-mediated response and supporting the involvement of a single receptor for the three neuropeptides. Phenotypic analysis showed that VIP, PACAP27, and PACAP38 protect predominantly CD4+CD8+ thymocytes from glucocorticoid- induced apoptosis. These findings suggest that these neuropeptides could be involved in intrathymic T-cell maturation.  相似文献   
22.
α-葡萄糖苷酶抑制剂治疗2型糖尿病的系统评价   总被引:4,自引:0,他引:4  
目的评价α-葡萄糖苷酶抑制剂治疗2型糖尿病患者的效果。方法检索Cochrane图书馆、MEDLINE、EMBASE、CurrentContents、LILACS在研试验数据库,主题为α-葡萄糖苷酶抑制剂的综述的参考文献,并联系纳入试验的专家与实施者。最近检索日期为2003年月12月(CurrentContents)和2003年4月(其他数据库)。纳入α-葡萄糖苷酶抑制剂单一疗法与其它干预比较,治疗2型糖尿病疗程至少12周的随机对照试验,并且试验至少包括以下结局之一:病死率、患病率、生活质量、血糖控制、血脂、胰岛素水平、体重、不良事件。两名评价者独立阅读所有摘要,评价质量并提取数据,分歧通过协商解决或由第三位评价者裁决。由一位统计学家在对提取数据输入数据库时进行检查。我们尽量联系所有作者以核实数据。结果共纳入41个试验、8130例受试者,其中30个针对阿卡波糖,7个针对米格列醇,1个针对优格列波糖,还有3个为不同α-葡萄糖苷酶抑制剂间的比较。绝大多数研究疗程为24周,仅有2个研究超过1年。与安慰剂相比,阿卡波糖血糖控制效果更好:糖化血红蛋白–0.8%[95%CI(–0.9,–0.7)],空腹血糖–1.1mmol/L[95%CI(–1.4,–0.9)],负荷血糖–2.3mmol/L[95%CI(–2.7,–1.9)],阿卡波糖对糖化血红蛋白的作用呈非剂量依赖。我们发现其可降低负荷胰岛素,但对血脂和体重未见临床相关的作用。不良反应主要来自胃肠道且与剂量相关。相对于磺脲,阿卡波糖将空腹和负荷胰岛素水平分别降低至–24.8pmol/L[95%CI(–43.3,–6.3)]和–133.2pmol/L[95%CI(–184.5,–81.8)],但阿卡波糖引起的不良反应更多。结论关于α-葡萄糖苷酶抑制剂是否影响2型糖尿病患者的病死率和患病率仍不清楚。相反,其对血糖控制或胰岛素水平作用明显,对血脂和体重的作用差异无统计学意义。α-葡萄糖苷酶抑制剂更长疗程的效果仍不确定。阿卡波糖剂量超过50mg(TID)时不能进一步影响糖化血红蛋白水平,不良反应反而更多,与磺脲相比,α-葡萄糖苷酶抑制剂降低了空腹和负荷胰岛素水平,但在血糖控制和不良反应方面存在不利影响。  相似文献   
23.
Human red cells (RBCs) were collected in CPDA-1 and then freeze-dried in lyoprotective solution. The lyophilized RBCs were then stored at -20 degrees C for 7 days. At the end of the storage period, the lyophilized RBCs were rehydrated and washed in dextrose saline. The washed, reconstituted, lyophilized RBCs were resuspended in final wash solutions of ADSOL, CPDA-1, or a special additive solution containing glucose, citrate, phosphate, adenine, and mannitol, and then they were stored at 4 degrees C for an additional 7 days. The main purpose of this study was to determine whether human RBCs can be lyophilized in such a manner that normal metabolic, rheologic, and cellular properties are maintained during rehydration and subsequent storage in standard blood bank preservative solutions. Our results show that reconstituted, lyophilized RBCs maintained levels of ATP, 2,3 DPG, lactate, and cellular properties that are equal to or better than those in control nonlyophilized RBCs stored for a comparable period in CPDA-1. Reconstituted, lyophilized RBCs stored at 4 degrees C after rehydration also show better maintenance of ATP, 2,3 DPG, and lactate than do control RBCs stored in the same preservative solutions for comparable periods.  相似文献   
24.
Summary Neuromuscular interaction between neck and jaw muscles has been reported in several studies. However, the influence of experimentally modified posture of the neck on jaw muscle activity during isometric biting was not investigated so far. The aim of the present study was to test by the aid of simultaneous electromyographic and intraoral bite force measurements whether neck rotation and lateroflexion, in contrast to a straightforward neck position, change the isometric cocontraction patterns of masticatory muscles under identical submaximum bite forces of 50–200 N. Electric muscle activity of all masticatory muscles and changes of the reduction point (RP) of the resultant bite force vectors were examined. An anteroposterior displacement of the RPs could be observed for the rotated and lateroflexed neck position in comparison with the straightforward position. On the other hand, the results revealed no significant differences between bilateral muscle activation under the different test conditions. These findings suggest a force transmission between the neck and the masticatory system, but no essential activity changes in the masticatory muscles under short time posture modification of the neck.  相似文献   
25.
The aim of this study was to determine the effectiveness of uterine artery embolization (UAE) as a primary treatment method in treatment of symptomatic fibroids, whether there are any preembolization MRI characteristics of fibroid predictive of reduction in volume and assess reduction in uterine and dominant fibroid volumes using ultrasound (US) and MRI. Study was carried out in total of 32 patients aged 25–49 years (mean 40.9 years). Uterine and dominant fibroid volume were determined using US and MRI before UAE, MRI and US at 3 months and US alone at 6 and 12 months post‐UAE, supplemented by clinical evaluation at interval of 3, 6 and 12 months. Procedure was carried out through unilateral femoral puncture using poly vinyl alcohol (PVA) particles 355–500 μm in size. All 32 patients had successful procedures. Overall, 25 patients responded, giving a clinical success rate of 78.12%. Mean reduction in volume of uterus and fibroid was 33 and 59.7% and 48.9 and 75.5% on US at 3 and 12 months respectively, and 33.3 and 58.6% on MRI at 3 months. Volume reduction on US and MRI at 3 months was highly correlative. There was no statistical difference in size reduction in volume of fibroids, which were hypointense or hyperintense on T2‐weighted image (T2WI) on pre‐UAE MRI. Uterine artery embolization leads to good technical success and fibroid volume reduction. Ultrasound alone may be used for follow up of patients post‐UAE. Preprocedure signal characteristics on T2WI are not predictors of volume reduction after UAE.  相似文献   
26.
In a prospective survey of infants born in a single maternity unit, asymptomatic faecal colonisation by Clostridium difficile occurred in 31 (47%) of 66 babies who provided a faecal sample during week one of life and at age 14 and 28 days, and in 46 (30.7%) of the total of 150 babies for whom at least one faecal sample was obtained during the month of study. There was no evidence for acquisition of the organism from the mother during delivery and colonisation was unrelated to the means of delivery, infant sex, means of feeding, duration of hospital stay, or antibiotic treatment. New colonisation occurred throughout the month of the study and further evidence for environmental acquisition was obtained by the finding of a similar strain of C difficile in 7 babies from one ward together with positive environmental cultures. Colonisation was frequently transient and occasionally intermittent; most infants kept the same strain during their period of carriage. Twenty two (47.8%) babies colonised by C difficile had low titres of cytopathic faecal toxin but none had symptomatic diarrhoea or features of necrotizing enterocolitis. The in vitro toxigenic potential of 57 toxigenic isolates from 36 babies was low and 12 babies carried non-toxigenic strains. Transient colonisation by C difficile in early life is almost certainly more common than is generally recognized and the neonate provides an important reservoir of potential infection.  相似文献   
27.
Interventional radiologic procedures in the renal transplant   总被引:1,自引:0,他引:1  
Percutaneous interventional procedures can be valuable in the evaluation and treatment of urologic complications of renal transplantation. Thirty-three patients underwent percutaneous procedures, including relief of obstruction by catheter nephrostomy, diagnostic antegrade pyelography with Whitaker testing, aspiration of various fluid collections (lymphocele, hematoma, urinoma, and abscess), and renal artery angioplasty, during a three year period at three institutions, to provide temporizing treatment and anatomic data. Surgical intervention was sometimes avoided, but more often it could be deferred to allow the patient to stabilize prior to surgery. Complications that required surgery occurred in two patients.  相似文献   
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