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81.
门静脉高压症联合手术前后血流动力学变化的临床意义 总被引:3,自引:0,他引:3
目的探讨门静脉高压症患者在联合手术前后血流动力学变化的临床意义。方法回顾性分析45例脾切除、贲门周围血管离断加脾肾静脉分流(简称联合手术)患者术前、术中、术后血流动力学的变化及其对临床疗效的影响。结果本组无手术死亡。术后门静脉自由压从(37±8)cmH_2O降至(30±4)cmH_2O,两者相比差异有统计学意义(P<0.05);门静脉入肝血流量从(1098±338)ml/min减至(995±293)ml/min,两者相比差异有统计学意义(P>0.05);肠系膜上静脉血流量从(605±288)ml/min增至(735±293)ml/min,两者相比差异有统计学意义(P<0.05)。42例(93%)患者得到随访,平均随访时间2年6个月,再出血发生率为4%,其中1例死亡。门静脉高压性胃病得到明显缓解,肝性脑病发生率为4%,未发现脾静脉血栓形成,肝功能得到一定程度的改善。结论联合手术是治疗门静脉高压症较为理想的有效术式。 相似文献
82.
Encephalopathy is a common complication of sepsis. However, little is known about the morphological changes that occur in the brain during sepsis. In this study, fecal peritonitis was induced in Wistar rats, which had been monitored for 4 h before their brains were removed and samples from the CA1 area taken. In addition to higher blood pressure with a decreasing pattern and a significant drop in rectal temperature, an increased heart rate and marked respiratory failure were observed. The tissue was investigated and compared with corresponding hippocampal samples taken from sham‐operated and not operated control groups. Significantly more peri‐microvascular edema was found in the hippocampal CA1 area in the septic group. The percentages of the peri‐microvascular edema were 158.57 ± 3.6%, 122.84 ± 1.5% and 120.24 ± 1.9% in the fecal peritonitis group, sham‐operated and not operated control groups, respectively. The results may suggest that the edema observed around the microvessels may participate in the pathogenesis of the septic encephalopathy probably by causing in the microvascular permeability characteristics. 相似文献
83.
Wernicke脑病的MRI诊断价值 总被引:1,自引:0,他引:1
目的探讨Wernicke脑病的MRI表现,以提高诊断水平。方法搜集7例经临床证实的Wernicke脑病的MRI资料进行回顾性分析。结果双侧丘脑、第三脑室周围广泛对称性异常信号(6例),导水管周围、桥脑被盖异常信号(7例),乳头体、丘脑下部、穹隆及四脑室周围异常信号(2例),上述病变呈长T1长T2信号,FLAIR序列呈高信号,2例DWI序列呈高信号,脑室壁模糊,2例静注Gd-DTPA增强后病变区域对比增强,1例可见侧脑室周围小血管放射状强化。结论Wernicke脑病具有典型的MRI表现,对临床诊断及治疗有重要意义。 相似文献
84.
A. J. Bullock R. A. Duquette N. Buttell S. Wray 《Pflügers Archiv : European journal of physiology》1998,435(4):575-577
Intracellular pH (pHi) is known to modulate contraction. Neonatal tissues can differ from adult tissue in contractile response to stimuli known
to alter pHi e.g. hypoxia. Changes of pH are attenuated by buffering, thus any difference in buffering power (β) between tissues could
affect their functional response to pHi perturbation. Similarly the extent to which any extracellular pH (pHo) alteration is transmitted into a pHi change will also influence function. We have therefore determined the intrinsic β and effect of pHo change on pHi in neonatal and adult ureteric, uterine and gastric smooth muscles using the pH-sensitive fluorophore carboxy-SNARF. β was
found to be similar in the three adult tissues, but there were significant differences between neonatal tissues. In contrast,
we found little difference in the amount of pHi change produced by pHo change between neonatal and adult tissues from the same smooth muscle, but a difference between smooth muscles. These data
highlight significant differences between smooth muscles and their developmental state, which may contribute to different
degrees of protection when pH is perturbed.
Received: 17 October 1997 / Received after revision: 27 November 1997 / Accepted: 28 November 1997 相似文献
85.
肝硬化患者的脑电活动地形图 总被引:1,自引:0,他引:1
对20例无临床肝性脑病的失代偿期肝硬化患者进行脑电活动地形图(BEAM)检查,并与33例正常人作对照,以探讨亚临床肝性脑病(SHE)的诊断价值。结果表明,20例肝硬化患者中,BEAM正常5例,轻度异常5例,轻 ̄中度异常5例,中度异常5例,总异常率为75%(15/20)。BEAM异常的分布特点以弥漫性分布为主要表现,主要为慢频域(δ.θ.δ+θ/α+β)活动增强,Z值增高,只有3例波及α频域。提示: 相似文献
86.
Acute toxicity of two pyrethroids,permethrin, and cypermethrin in neonatal and adult rats 总被引:2,自引:0,他引:2
Franco Cantalamessa 《Archives of toxicology》1993,67(7):510-513
The present study aims specifically at obtaining a comparison of the acute toxicity of cypermethrin (CY), a type I pyrethroid, and permethrin (PERM), a type II pyrethroid, administered orally as a single dose to neonatal and adult rats, and at assessing the importance of pyrethroid biotransformation in CY and PERM toxicity through use of drug metabolism inhibitors. Our experiments show that CY is more toxic than PERM to adult and neonatal rats. The sensitivity of neonatal rats both to CY and to PERM toxicity is higher, the younger the animals. CY is much more toxic than PERM in the neonatal rat, compared with the adult. In rats aged 8, 16, and 21 days, pretreatment with piperonil butoxide (PB), a monooxygenase inhibitor, or with tri-o-tolyl phosphate (TOTP), an esterase inhibitor, does not produce significant variations in the lethal effects of CY and PERM. Instead, in the adult rats, a significant increase in CY (X2=5.97;p<0.05) and PERM (X2=4.37;p<0.05) mortality occurred in rats pretreated with esterase inhibitors, whereas no increase in CY and PERM toxicity was found in adult animals pretreated with monooxygenase inhibitor. It was concluded that the higher level of sensitivity of the neonate rat to pyrethroid toxicity is probably due to incomplete development of the enzymes which catalyze the metabolism of pyrethroids in the liver of young animals. It is suggested that ester hydrolysis is an important pyrethroids detoxification reaction in the adult rat. 相似文献
87.
Despite the existence of a well-defined abstinence syndrome in offspring of opiate-dependent mothers, the mechanisms involved in neonatal abstinence remain unclear. The goal of the present study was to determine the contribution of noradrenergic neurons in the opiate abstinence syndrome in neonatal rats (10 days old). First, the ability of the α2-adrenergic agonist, clonidine to attenuate the symptoms of neonatal opiate abstinence precipitated by naloxone was determined. Secondly, the activity of noradrenergic neurons was determined by measuring postmortem levels of 3-methoxy-4-hydroxyphenylglycol (MHPG) in the hypothalamus, hippocampus and cortex in opiate-abstinent pups. Neonatal opiate abstinence was characterized by an increased incidence of wall climbing, tremors and mouthing. Acute treatment with morphine and naloxone in chronic saline-treated pups also produced the tremor, albeit less severe than in pups treated chronically with morphine. Clonidine (0.2 mg/kg) attenuated the expression of tremor and mouthing in neonates, but increased wall climbing. Clonidine elicited wall climbing in opiate-naive neonates. Treatment with morphine followed by naltrexone increased MHPG levels in all of the brain areas examined, irrespective of the chronic treatment, but naltrexone treatment elicited a larger increase in MHPG levels in pups treated chronically with morphine. Acute morphine treatment increased MHPG levels only in the hypothalamus. The results of the present study provide behavioral and neurochemical data supporting the hypothesis that noradrenergic hyperactivity plays a role in neonatal opiate abstinence. 相似文献
88.
第二产程时限与新生儿结局的关系 总被引:7,自引:1,他引:6
目的探讨第二产程时限对新生儿预后的影响。方法将216例单胎、足月、无阴道分娩禁忌证的初产妇按照第二产程持续时间(t)分为4组,比较4组间新生儿结局情况。结果手术产率、脐动脉酸血症发生率及新生儿转入新生儿加强监护病房(NICU)的发生率在t>90 m in组明显高于t≤30m in组、3090 m in,新生儿不良结局发生率增加,故应重视和积极处理第二产程。 相似文献
89.
新型壳聚糖对血浆胆红素和细胞因子吸附性能的体外筛选初步研究 总被引:7,自引:0,他引:7
目的观察各类新型吸附剂对重型肝炎患者血浆中的胆红素和细胞因子的吸附性能。方法第一步,收集第一组重型肝炎患者的血浆各3ml,以8种不同的吸附剂(1#~3#为致孔剂浓度分别为3%、1%、5%的壳聚糖,4#为胺基化壳聚糖,5#为苯乙烯/二乙烯苯聚合物,6#为后交连苯乙烯/二乙烯苯聚合物,7#为壳聚糖-苯乙烯/二乙烯苯聚合物,8#为壳聚糖-后交连苯乙烯/二乙烯苯聚合物)各1ml进行吸附,检测对胆红素的吸附能力,做吸附剂筛选实验和吸附实验。第二步,用以上筛选出吸附率较好的两种吸附剂各1ml对第二组患者血浆(各3ml)进行胆红素和细胞因子的吸附实验。结果第一步实验显示胺基壳聚糖(4#)和苯乙烯/二乙烯苯聚合物(5#)有较好的吸附效果,4#吸附剂对总胆红素(TBiL)、直接胆红素(DBiL)、间接胆红素(IBiL)的吸附率分别为50.5%±3.4%、57.0%±11.3%、39.0%±7.2%;5#分别为30.1%±2.5%、32.6%±3.0%、27.6%±2.9%。第二步实验显示4#胺基化壳聚糖吸附后血浆中TBiL、DBiL、IBiL、白细胞介素6(IL-6)和肿瘤坏死因子α(TNF-α)水平下降比5#明显,有统计学意义(P<0.001)。结论胺基化壳聚糖(4#)体外吸附重型肝炎患者血浆中胆红素、细胞因子效果有明显优势。 相似文献
90.
目的:观察肝素对患感染性疾病的新生儿组织因子途径抑制物(TFPI)的影响。方法:采用酶联免疫吸附试验(ELISA)法检测了32例患感染性疾病的新生儿在使用肝素前和使用肝素后30~45分钟、6小时血浆TFPI的变化,并与患儿对照组、正常对照组及文献进行比较。结果:患儿治疗组使用肝素后30~45分钟血浆TFPI水平明显增高(t=3.953,P<0.001),6小时血浆TFPI又几乎降至用药前水平(t=0.141,P<0.05)。结论:新生儿对肝素的反应与成人不同。 相似文献