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81.
Summary  The aim of this study is to find out the effects of different doses of midazolam, when used epidurally, on somatosensory evoked potentials (SEP) by delaying neuronal conduction. Thirty two New Zeland albino male rabbits were divided into four groups. All rabbits were anesthetised with ketamine and xylasine combination and atracurium was used as muscle relaxant. 10 mg/kg/hr ketamine infusion was used for maintenance of anesthesia. After insertion of the epidural catheter surgically; Group 1 received 1.5 ml isotonic saline (Control), Group 2 received 150 μg/kg, Group 3 received 250 μg/kg, and Group 4 received 500 μg/kg midazolam epidurally. With the stimulation of sciatic nerve, SEP records were recorded from the epidural space. Records were received before the injection of the drug, and 20, 40, 60 minutes after injection of the drug.  “Latancy” results were increased according to control in all groups (including isotonic saline-control-group). Increase in latancy in the control group was interpreted as due to the effect of temperature mismatch of the saline and the rabbits. While in the first and second group amplitudes showed no differences, group 3 and 4 showed decreases of up to 50%. Epidurally administered midazolam up to 150 μg/kg caused no change in SEP records, but 250 and 500 μg/kg doses caused decreases in SEP records which can lead to misinterpretation as neurological damage.  相似文献   
82.
BACKGROUND: Recently, there have been large outbreaks of hand, foot and mouth disease (HFMD) mainly caused by enterovirus 71 (EV71) associated with severe neurological diseases in the Western Pacific Region (WPR). To monitor the realtime trend of EV71 transmission throughout the WPR, the authors conducted a molecular epidemiological analysis of EV71 infection. METHODS: Viruses were isolated from clinical samples from patients with HFMD or those with neurological complications. The EV71 isolates were identified by microneutralization assay. The VP4 and/or VP1 regions of recent EV71 isolates were sequenced and subjected to phylogenetic analysis using reference EV71 strains. RESULTS: The phylogenetic analysis of EV71 isolates from the WPR revealed two major genogroups, B and C, based on the nucleotide sequence alignment of the VP1 or VP4 region. These two major genogroups were further divided into subgenogroups, B1, B2, B3, and B4 and C1, C2, C3 and C4, respectively. CONCLUSIONS: The molecular epidemiological analyses of recent and previous EV71 isolates in the WPR indicated that two major genogroups of EV71 are co-circulating in Australia, Malaysia, Singapore, Taiwan and Japan. Recent EV71 isolates in Mainland China constitute a new distinct genetic cluster, subgenogroup C4. Two major lineages of EV71 are the major causative agents of the present HFMD epidemics in the WPR and both are considered to be neurovirulent.  相似文献   
83.
Abstract Background : The aim of the present study was to determine the prevalence, associated symptoms, and clinical outcomes of children with acute abdominal pain who had been admitted to an emergency department. Methods : Children aged between 2 and 16 years who presented to the emergency department of Cerrahpa?a Medical School, Istanbul University between July 2001 and August 2002 with acute abdominal pain were enrolled in this study. A questionnaire was completed each patient admitted to our pediatric emergency unit for acute abdominal pain. Data collected included presenting signs and symptoms, the hospital follow up for all children who returned within 10 days, test results, and telephone follow up. Results : The number of children referred to the emergency department was 7442, with 399 (5.4%) of these having acute abdominal pain. The mean age of the study population was 6.9 ± 3.5 years, and 201 of the patients were male. The five most prevalent diagnoses were: (i) upper respiratory tract infection and/or complicated with otitis media or sinusitis (23.7%); (ii) abdominal pain with uncertain etiology (15.4%); (iii) gastroenteritis (15.4%); (iv) constipation (9.4%); and (v) urinary tract infection (8%). The most common associated symptoms were decreased appetite, fever and emesis. Because of follow‐up deficiency the progress of 28 patients was not obtained. Eighty‐two children were referred to the department of pediatric surgery, but only 17 of 82 (20.7%) required surgical intervention (15 of these 17 for appendicitis). Eleven patients returned within 10 days for re‐evaluation, but the initial diagnosis was not changed. The complaints of 57 patients with uncertain etiology were resolved within 2 days. Conclusions : An acute complaint of abdominal pain was usually attributed to a self‐limited disease. However, the percentage of surgical etiology is not negligible.  相似文献   
84.
Percutaneous nephrolithotomy in older children   总被引:4,自引:0,他引:4  
PURPOSE: The aim of this study was to evaluate the safety and efficacy of percutaneous nephrolithotomy (PCNL) in pediatric patients, older than 8 years, without any technical and instrumental modifications. METHODS: The authors retrospectively evaluated the data of 16 percutaneously treated kidneys of 14 patients with a mean age of 11 years (range, 8 to 17). The mean stone burden was calculated as 301 mm2 (range, 120-750). Percutaneous accesses were done under fluoroscopic control, and 24F to 30F Amplatz dilators were used depending on patient size. Ultrasonic and laser lithotripsy were performed to fragment calculi. RESULTS: Mean operating time was 111 minutes (range, 60 to 210 min) and no intraoperative or postoperative major complication was observed. Mean hemoglobin drop after the procedure was 1.16 g/dL (range, 0.3 to 2.8). Blood transfusion was required in only 1 patient, and mean postoperative hospitalization was 4.6 days (range, 3 to 10). Stone-free rate was calculated as 69% (11 of 16), but with residual fragments smaller than 4 mm, the success rate becomes 100% at patient's discharge. CONCLUSIONS: PCNL is an effective and safe form of therapy in pediatric stone disease. Especially in older children the use of the same instruments and technique as in adults may achieve equal results without any increased risk of possible morbidity and need of blood transfusion.  相似文献   
85.
BACKGROUND: Exposure to organochlorine compounds (OCs) has been a subject of interest in recent years, given their potential neurotoxicity. Meconium is easily available and accumulates neurotoxicants and/or metabolites from the 12th week of gestation. AIMS: To determine whether neurotoxicants, specifically OCs, could be detected in serially collected meconium, and to compare the results with those obtained in cord blood samples. METHODS: A sample of cord blood and three serial stool samples were analysed in 10 newborns. Pentachlorobenzene (PeCB), hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs), dichlorodiphenyl trichloroethane (p,p'-DDT) and its metabolite dichlorodiphenyl dichloroethylene (p,p'-DDE), and hexachlorocyclohexane isomers (alpha-, beta-, gamma-, and delta-HCH) were analysed by gas chromatography. RESULTS: From serial stool collection and analysis in newborns, there was an increase in the concentrations of HCB, p,p'-DDE, PCBs, and beta-HCH between the first and last stools of the newborn. Levels of DDT diminished as pregnancy progressed. Concentrations in cord blood were positively associated with concentrations in meconium for p,p'-DDE and beta-HCH. CONCLUSIONS: Meconium is a very useful instrument for the investigation of fetal exposure to neurotoxicants; serial collection and analysis of meconium should estimate the timing and degree of in utero exposure of the fetus to neurotoxicants. Analysis and interpretation of neurotoxicants in meconium results is a complex process. Measurement in meconium of a wide range of neurotoxic substances should facilitate early identification of harmful exposures, and enable rehabilitation and instigation of preventive measures.  相似文献   
86.
BACKGROUND: The bradykinin (BK)-induced endothelium-dependent relaxation is impaired in the presence of elevated potassium concentration enhancing the vasospastic tendency of large coronary arteries. Inhibition of the angiotensin-converting enzyme responsible for bradykinin degradation was found to enhance the endothelium-dependent relaxation by BK. The aim of the present study was to investigate the effect of phosphoramidon, known to inhibit a BK-metabolizing neutral endopeptidase enzyme, on relaxation of porcine-isolated coronary artery in depolarizing solution. METHODS: Endothelium intact porcine coronary artery rings were studied in organ chambers. The rings were isometrically contracted with potassium chloride (30 mmol/L) and the response to BK (1 to 1,000 nmol/L)-induced relaxation was investigated in the presence of nitric oxide synthase inhibitor Nomega-nitro-L-arginine (300 micromol/L) alone and in combination with the cyclooxygenase inhibitor indomethacin (10 micromol/L), and that of the inhibitor of calcium-dependent potassium channels tetraethylammonium (7 mmol/L). Under these conditions, phosphoramidon (10 micromol/L), an inhibitor of a neutral endopeptidase enzyme (EC.3.4.24.11.), which is responsible for the degradation of BK, was used to enhance the endothelium-dependent relaxation. RESULTS: Phosphoramidon potentiated the maximum vasorelaxant effect of BK in Nomega-nitro-L-arginine (control 26.6%+/-10.86% versus phosphoramidon 49.05%+/-4.52%; n = 6, p < 0.05) or in Nomega-nitro-L-arginine + indomethacin-pretreated rings (control 20.7%+/-9.92% versus phosphoramidon 42.0%+/-12.26%; n = 5, p < 0.05) and this increased vasodilation was not modified by tetraethylammonium. CONCLUSIONS: In the present study phosphoramidon potentiated the effect of BK in the absence of nitric oxide and prostaglandins in porcine-isolated coronary artery. This effect did not depend on tetraethylammonium-sensitive potassium channels. Phosphoramidon may be a useful pharmacologic tool for preserving the vasorelaxing capacity of coronary arteries after cardioplegia.  相似文献   
87.
目的 探讨慢性乙型肝炎患者中医辨证分型与肝脏病理改变及血清转化生长因子(TGF) β1含量的关系。方法 对92例慢性乙型肝炎患者进行肝组织病理诊断和中医分型。采用酶联免疫吸附试验(ELISA)测定92例患者血清TGF β1。结果 ①92例患者病理分型,轻度6 5例,中度19例,重度8例;②92例患者中医分型为肝郁脾虚型4 9例,湿热中阻型3例,肝肾阴虚型11例,脾肾阳虚型6例,瘀血阻络型2 3例;③病理分型轻度者以肝郁脾虚型为主(72 % ) ,中度者瘀血阻络型占6 3% ,重度者8例均为瘀血阻络型;④肝郁脾虚型者血清TGF β1含量最低,肝内纤维化程度轻;瘀血阻络型患者血清TGF β1含量最多,肝内纤维化程度最重(P <0 .0 1) ,其余3型介于两者之间,血清TGF β1含量差异无统计学意义(P >0 . 0 5 )。结论 慢性乙型肝炎以肝郁脾虚型为主,随着肝损害加重,瘀血阻络型逐渐增加。因此,对慢性乙型肝炎轻度者要注重疏肝健脾,对中、重度者要注意活血化瘀  相似文献   
88.
89.
Changes in cellular lipid metabolism are a common feature in most solid tumors, which occur already in early stages of the tumor progression. However, it remains unclear if the tumor‐specific lipid changes can be detected at the level of systemic lipid metabolism. The objective of this study was to perform comprehensive analysis of lipids in breast cancer patient serum samples. Lipidomic profiling using an established analytical platform was performed in two cohorts of breast cancer patients receiving neoadjuvant chemotherapy. The analyses were performed for 142 patients before and after neoadjuvant chemotherapy, and the results before chemotherapy were validated in an independent cohort of 194 patients. The analyses revealed that in general the tumor characteristics are not reflected in the serum samples. However, there was an association of specific triacylglycerols (TGs) in patients' response to chemotherapy. These TGs containing mainly oleic acid (C18:1) were found in lower levels in those patients showing pathologic complete response before receiving chemotherapy. Some of these TGs were also associated with estrogen receptor status and overall or disease‐free survival of the patients. The results suggest that the altered serum levels of oleic acid in breast cancer patients are associated with their response to chemotherapy.  相似文献   
90.
刘炜  黄志力  曲卫敏 《中国药学杂志》2009,44(23):1786-1790
 目的 内源性前列腺素( prostaglandin, PG ) D2 能增加基底前脑下蛛网膜下腔内的腺苷水平,可能作用于腺苷 A 2A 受体,诱发睡眠。本实验观察腺苷 A 2A 受体特异性激动剂 CGS21680 和 PGD2 促眠作用的异同。 方法 手术插入不锈钢导管至大鼠基底前脑下蛛网膜下腔,同时埋植脑电波和肌电波记录电极,术后 2 周,经导管微量恒速灌注 PGD2 ( 200 pmol·0.2 μL-1·min-1 )或 CGS21680 ( 10 pmol·0.2 μL-1·min-1 ),同步记录脑电波和肌电波,分析睡眠量、睡眠强度及睡眠时相转换等参数。 结果 与人工脑脊液自身对照相比, PGD2 和 CGS21680 都显著增加慢波睡眠(非快动眼睡眠)量和睡眠强度,两者在时相转化和各波段时程上表现出高度的相似性。 CGS21680 增加快动眼睡眠量,而 PGD2 不引起快动眼睡眠量的增加。 结论 ■ 腺苷 A 2A 受体激动剂 CGS21680 能模拟 PGD2 诱发的慢波睡眠,提示腺苷 A 2A 受体是诱导生理性睡眠的重要靶点之一。  相似文献   
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