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91.
92.
目的探讨神经干细胞(NSCs)移植对创伤性脑损伤(TBI)模型大鼠感觉运动功能的恢复作用及其对损伤脑组织中突触素(SYP)表达的影响。方法体外培养大鼠胚胎皮质NSCs;采用Feeney法制备TBI模型,于造模后72h,移植组采用PKH26荧光示踪剂标记的NSCs直接移植于脑损伤区,对照组以等量生理盐水代替NSCs;分别于移植后不同时间点,采用Gridwalk和Latency试验检测TBI大鼠的感觉运动功能;荧光显微镜下计数移植细胞的存活数量;采用免疫印迹和RT-PCR技术检测脑损伤区及周围组织中SYP的表达。结果 NSCs移植大鼠前、后肢功能分别在移植后第2w和4w恢复至手术前水平,而直到第8w,对照组大鼠后肢功能和通过平板移动时间与NSCs移植组和基线比较仍有显著性差异(P〈0.05)。移植的NSCs随移植时间延长存活数量减少,移植后第4w和8w的存活数分别为6.3%±1.0%和4.1%±0.9%。在移植后的8w期间,移植组脑损伤区及周围组织中SYP的表达均明显高于对照组(P〈0.05)。结论移植的NSCs在TBI脑内能够存活,并明显改善了TBI大鼠对侧肢体的感觉运动功能;NSCs移植促进了脑损伤区及周围组织中SYP的表达,这可能是NSCs移植促进功能恢复的机理之一。  相似文献   
93.
目的:总结二尖瓣置换术后左心室破裂2例临床经验教训,方法:回顾性分析我院2006,1-2009,12二尖瓣置换术后左心室破裂2例的临床资料,两例均在监护室里发生突然大出血,紧急输血,输液,机械呼吸,抗休克治疗,并行开胸手术。结果:一例心外修补抢救成功,术后2周顺利出院,一例CPB下心内外修补,因低心排综合症死亡。结论:左心室破裂是二尖瓣置换术最严重的并发症,一旦发生死亡率极高,因此预防,避免其相关因素更关键。  相似文献   
94.
A novel impulsive cell pressurization experiment has been developed using a Kolsky bar device to investigate blast-induced traumatic brain injury (TBI). We demonstrate in this video article how blast TBI-relevant impulsive pressurization is applied to the neuronal cells in vitro. This is achieved by using well-controlled pressure pulse created by a specialized Kolsky bar device, with complete pressure history within the cell pressurization chamber recorded. Pressurized neuronal cells are inspected immediately after pressurization, or further incubated to examine the long-term effects of impulsive pressurization on neurite/axonal outgrowth, neuronal gene expression, apoptosis, etc. We observed that impulsive pressurization at about 2 MPa induces distinct neurite loss relative to unpressurized cells. Our technique provides a novel method to investigate the molecular/cellular mechanisms of blast TBI, via impulsive pressurization of brain cells at well-controlled pressure magnitude and duration.  相似文献   
95.
Alteration of electrical function in mammalian gastric mucosa is considered as an indicator of gastric barrier rupture. Measurements of transmucosal potential difference (PD) and electrical resistance (R) have documented such alterations to a variety of mucosal damaging agents. This study was designed to test whether the rat gastric mucosa exhibits circadian rhythms in acid secretion and electrical function and whether the damage produced by a mucosal acting agent (butyric acid) is also circadian-stage dependent. Mucosa was isolated from the gastric body of male rats standardized from birth to a light-dark regimen. Circadian rhythms of acid secretion and PD and R with acrophases during the dark hours were documented. Administration of butyric acid produced circadian-stage dependent damage with an acrophase also during the dark-phase span. Thus, in this experimental model, measurements of electrical function represented a poor index of gastric mucosal susceptibility to damaging agents. The authors discuss the possibility that rhythms other than those related to electrical function may better define mucosal vulnerability to ulcerogenesis.  相似文献   
96.
【摘 要】 目的 分析胎膜早破新生儿口腔分泌物细菌的分布特点、耐药情况以及不同分娩方式的影响,为临床合理的预防性使用抗生素提供科学的指导。方法 对2011年1月至2012年12月广东省妇幼保健院新生儿科送检的116份胎膜早破新生儿口腔分泌物标本进行细菌培养,并以法国梅里埃的全自动细菌鉴定药敏系统(VITEK-2 compact)对分离出的纯菌株进行鉴定和药敏试验,统计不同分娩方式的阳性率。结果 116份口腔分泌物标本中,共分离出细菌33株/31例,总检出率为26.7%,其中G-菌28株,占84.8%,G+菌5株,占15.2%,检出率最高的病原菌是大肠埃希菌17株(51.5%),其除了对丁胺卡那霉素、头孢替坦和亚胺培南全部敏感以外,对其他的抗生素均有不同程度的耐药,两种分娩方式的细菌培养阳性率差异无统计学意义。结论 胎膜早破新生儿口腔分泌物培养以G-菌为主且耐药性较高,临床应根据药敏结果合理选用抗生素进行预防用药;在无医学指针的情况下,推荐阴道分娩。  相似文献   
97.
目的:探讨单胎妊娠早产胎膜早破发生新生儿呼吸窘迫综合征(respiratory distress syndrome,RDS)的危险因素。方法:选择2017年5月至2019年5月在我院产科分娩的2810例产妇为研究对象,其中97例(3.45%)符合未足月胎膜早破(Preterm premature rupture of membranes,pPROM)标准,包括53例RDS。收集以下信息:PROM潜伏期、出生时胎龄、脐动脉搏动指数(Umbilical artery pulsatility index,UAPI)、大脑中动脉搏动指数(Middle cerebral artery pulsation index,MCAPI)、胎儿窘迫、产前使用类固醇、新生儿实验室参数、性别、体重、Apgar评分、分娩类型、妊娠高血压疾病、妊娠期糖耐量异常或糖尿病等信息,通过Logistic回归分析研究变量对RDS的影响。结果:Logistic回归分析结果显示,以下变量与RDS密切相关:新生儿性别女性(OR=0.517;95%CI:0.312-0.107;P=0.042),产前使用类固醇(OR=0.467;95%CI:0.355-0.698;P0.001),异常UAPI(OR=2.830;95%CI:1.783-6.234;P=0.002),异常MCA PI(OR=2.136;95%CI:1.120-4.017;P=0.032),胎儿窘迫(OR=2.420;95%CI:1.287-4.824;P=0.017),母体HGB(OR=0.689;95%CI:0.511-1.013;P=0.221),新生儿HGB(OR=0.752;95%CI:0.645-0.891;P0.001),新生儿RBC(OR=0.311;95%CI:0.201-0.565;P0.001)。结论:单胎妊娠早产胎膜早破发生RDS危险因素主要是性别、胎儿胎盘循环异常和胎儿窘迫。  相似文献   
98.
The authors examined the presence of Substance P (SP) and Vasoactive Intestinal Polypeptide (VIP) and their related fibers in the pseudocapsule of uterine fibroids (PUF) and in normal myometrium (NM) during myomectomies in 57 non-pregnant women. 4 samples were removed from the normal myometrium (NM) and from PUF. The samples were sent for histological and immune-fluorescent investigations. SP and VIP values were found non-significantly higher in PUF than in NM: SP values were 10.2 ± 0.1 conventional units (C.U.) in PUF at the fundus of the uterus (FU) vs. 8.1 ± 0.6 C.U. of NM in the FU (p > 0.05), and SP values were 25.1 ± 0.9 C.U. in PUF in the uterine body (UB) compared to. 23.2 ± 1.4 C.U. of NM in the myometrium of the UB (p > 0.05). VIP values were 11.5 ± 0.9 C.U. in the PUF in FU compared to 9.8 ± 1.4 C.U. of NM in the FU (p > 0.05), and VIP values were 33.9 ± 3.9 C.U. in the PUF in the UB vs. 32.6 ± 4.8 C.U. of the NM in the UB (p > 0.05). These findings show that SP and VIP neurofibers are present in the fibroid pseudocapsule, similar to the values in the normal myometrium of a non-pregnant uterus. An intracapsular myoma excision which respects the pseudocapsule permits a physiological healing process of the uterine scar, due to a neurotransmitter sparing at the hysterotomic site. In women planning pregnancy, the myomectomy should be preferably performed respecting the pseudocapsule in order to preserve the neurotransmission.  相似文献   
99.
Splenic infarction is a rare complication in malaria cases, and is caused primarily by Plasmodium falciparum. Recently in South Korea, only P. vivax has prevailed since 1993. Although the probability that symptomatic splenic infarction may occur in vivax malaria cases is considered relatively high, there have never been any case reports describing the occurrence of symptomatic splenic infarction in cases of vivax malaria. A 34-year-old man presented with fever that had persisted for 5 days. P. vivax infection was verified using a peripheral blood smear, and chloroquine was utilized to treat the fever successfully. Six days later, the patient developed pain in the left upper abdomen, which was diagnosed as splenic infarction by computed tomography.  相似文献   
100.
Zhang L  Zhang WP  Chen KD  Qian XD  Fang SH  Wei EQ 《Life sciences》2007,80(6):530-537
Traumatic brain injury induces neuron damage in early phase, and astrogliosis and the formation of the glial scar in late phase. Caffeic acid (3, 4-dihydroxycinnamic acid), one of the natural phenolic compounds, exerts neuroprotective effects against ischemic brain injuries with anti-oxidant and anti-inflammatory properties, and by scavenging reactive species. However, whether caffeic acid has protective effects against traumatic brain injury is unknown. Therefore, we determined the effect of caffeic acid on the lesion in the early (1 day) and late phases (7 to 28 days) of cryoinjury in mice. We found that caffeic acid (10 and 50 mg/kg, i.p., for 7 days after cryoinjury) reduced the lesion area and attenuated the neuron loss around the lesion core 1 to 28 days, but attenuated the neuron loss in the lesion core only 1 day after cryoinjury. Moreover, caffeic acid attenuated astrocyte proliferation, glial scar wall formation and glial fibrillary acidic protein (GFAP) protein expression in the late phase of cryoinjury (7 to 28 days). Caffeic acid also inhibited the reduction of superoxide dismutase activity and the increase in malondialdehyde content in the brain 1 day after cryoinjury. These results indicate that caffeic acid exerts a protective effect in traumatic brain injury, especially on glial scar formation in the late phase, which at least is associated with its anti-oxidant ability.  相似文献   
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