有关医院空调水系统若干问题的探讨

主要阐述空调水系统利用平衡阀调节系统阻力,保持系统水力稳定;利用软启动器实施水泵的平滑软启动;压差旁通阀的作用及选型安装;系统管道热膨胀等问题。     

大鼠小肠缺血再灌注后血中NO,SOD浓度及肺中Bax,Bcl-2表达的改变

目的：研究大鼠小肠缺血再灌注后后血中一氧化氮（NO），超氧化物歧化酶（SOD）的浓度变化以及肺组织中Bax,Bcl-2的表达，探讨小肠缺血再灌注后对肺组织的损伤，方法：建立小肠缺血再灌注模型，分对照 ，再灌注后0，30min，1，2h,1,3,7d共8组，于各时点检测血中Bax,Bcl-2的表达情况。结果：大鼠小肠缺血再灌注后NO浓度0min明显升高，2h时降低，随后升高，7d时达高峰，SOD浓度0min明显下降，2h 时升高，随后下降，7d时达最低，Bax,Bcl-2免疫阳性细胞主要位于肺组织中血管内皮细胞和肺泡上皮细胞，再灌注0min,Bax,Bcl-2阳性细胞率增多，30min时Bax,Bcl-2阳性细胞率均升高分别为17．1％和78．1％，Bcl-2表达高于Bax，两者差别显著（P＜0．01），2h时降低，其后升高，7d时阳性细胞率达高峰分别为94．1％和83．4％，Bax表达明显高于Bcl-2，两者差异显著（P＜0．01）。结论：大鼠小肠缺血再灌注后可引起血中NO，SOD的浓度变化和Bax及Bcl-2阳性细胞在肺组织中的表达改变并可能引起肺组织细胞凋亡和损伤。     

组织多肽特异性抗原在原发性肝癌中的临床应用

OBJECTIVE: To evaluate the clinical value of serum tissue polypeptide specific antigen (TPS) for primary hepatic cancer in comparison with alpha-fetoprotein (AFP). METHODS: TPS and AFP were measured by enzyme-linked immunosorbent assay (ELISA) in 85 patients with primary hepatic cancer, 19 with metastatic hepatic cancer, 35 with liver cirrhosis, 22 with chronic hepatitis and 50 healthy control subjects. RESULTS: Serum AFP levels were elevated in patients with hepatocellular carcinoma in comparison with that in cholangiocarcinoma patients (P=0.037), but the difference was not significant (P=0.737). Serum TPS levels were significantly correlated with the tumor size (P=0.001), but not with the number of the tumors, portal invasion, extrahepatic metastasis, clinical stage or histological differentiation (P>0.05). A significant correlation was observed between AFP level and tumor size (P=0.028), portal invasion(P=0.005), and histological differentiation (P=0.000). CONCLUSION: TPS alone offers no more clues than AFP for the diagnosis of primary hepatic cancer, though it can be helpful for the diagnosis of cholangiocarcinoma. It has only limited clinical utility as a marker for primary hepatic cancer.     

Altered central micro-opioid receptor binding after psychological trauma.

BACKGROUND: Functional neuroimaging studies have detected abnormal limbic and paralimbic activation to emotional probes in posttraumatic stress disorder (PTSD), but few studies have examined neurochemical mechanisms that underlie functional alterations in regional cerebral blood flow. The mu-opioid neurotransmitter system, implicated in responses to stress and suppression of pain, is distributed in and is thought to regulate the function of brain regions that are implicated in affective processing. METHODS: Here we examined the micro-opioid system with positron emission tomography and the micro-opioid receptor-selective radiotracer [11C] carfentanil in 16 male patients with PTSD and two non-PTSD male control groups, with (n = 14) and without combat exposure (n = 15). Differences in micro-opioid receptor binding potential (BP2) were detected within discrete limbic and paralimbic regions. RESULTS: Relative to healthy controls, both trauma-exposed groups had lower micro-opioid receptor BP2 in extended amygdala, nucleus accumbens, and dorsal frontal and insular cortex but had higher BP2 in the orbitofrontal cortex. PTSD patients exhibited reduced BP2 in anterior cingulate cortex compared with both control groups. Micro-opioid receptor BP2 in combat-exposed subjects without PTSD was lower in the amygdala but higher in the orbitofrontal cortex compared with both PTSD patients and healthy controls. CONCLUSIONS: These findings differentiate the general response of the micro-opioid system to trauma from more specific changes associated with PTSD.     

Isoflurane Preconditioning Improves Long-term Neurologic Outcome after Hypoxic-Ischemic Brain Injury in Neonatal Rats

Background: Preconditioning the brain with relatively safe drugs seems to be a viable option to reduce ischemic brain injury. The authors and others have shown that the volatile anesthetic isoflurane can precondition the brain against ischemia. Here, the authors determine whether isoflurane preconditioning improves long-term neurologic outcome after brain ischemia.

Methods: Six-day-old rats were exposed to 1.5% isoflurane for 30 min at 24 h before the brain hypoxia-ischemia that was induced by left common carotid arterial ligation and then exposure to 8% oxygen for 2 h. The neuropathology, motor coordination, and learning and memory functions were assayed 1 month after the brain ischemia. Western analysis was performed to quantify the expression of the heat shock protein 70, Bcl-2, and survivin 24 h after isoflurane exposure.

Results: The mortality was 45% after brain hypoxia-ischemia. Isoflurane preconditioning did not affect this mortality. However, isoflurane preconditioning attenuated ischemia-induced loss of neurons and brain tissues, such as cerebral cortex and hippocampus in the survivors. Isoflurane also improved the motor coordination of rats at 1 month after ischemia. The learning and memory functions as measured by performance of Y-maze and social recognition tasks in the survivors were not affected by the brain hypoxia-ischemia or isoflurane preconditioning. The expression of Bcl-2, a well-known antiapoptotic protein, in the hippocampus is increased after isoflurane exposure. This increase was reduced by the inhibitors of inducible nitric oxide synthase. Inducible nitric oxide synthase inhibition also abolished isoflurane preconditioning-induced neuroprotection.     

Incidence of Type 2 diabetes in England and its association with baseline impaired fasting glucose: the Ely study 1990-2000.

AIM: To determine the incidence of Type 2 diabetes and to examine the effect of different cut-points for impaired fasting glucose (IFG) on diabetes incidence. METHODS: Population-based longitudinal study (1990-2000) with clinical, anthropometric and biochemical measurements, including an oral glucose tolerance test (OGTT), in 1040 non-diabetic adults aged 40-69 years at baseline. Baseline glucose status was defined as normoglycaemia < 5.6, IFG-lower 5.6-6.0 and IFG-original 6.1-6.9 mmol/l. The all-IFG group included fasting glucose values of 5.6-6.9 mmol/l. RESULTS: The 10-year cumulative incidence of diabetes was 7.3 per 1000 person-years. Diabetes incidence was 2.4 [95% confidence interval (CI) 1.2, 4.8], 6.2 (4.0, 9.8) and 17.5 (12.5, 24.5) per 1000 person-years in those with normoglycaemia, IFG-lower and IFG-original, respectively. Compared with normoglycaemia, the age/sex-adjusted risk [hazard ratio (HR) and 95% CI] for incident diabetes was greatest in the IFG-original category (HR 6.9; 3.1, 15.2) and increased to a lesser degree in the IFG-lower (HR 2.5; 1.1, 5.7) and all-IFG categories (HR 4.1; 1.9, 8.7). When adjusted for confounding factors, the magnitude and direction of associations persisted, with HR 1.9, 4.4 and 2.9, for the categories IFG-lower, IFG-original and all-IFG, respectively. CONCLUSIONS: Diabetes incidence is more strongly related to IFG defined as fasting glucose between 6.1 and 6.9 mmol/l than to the lower category of 5.6-6.0 mmol/l, or entire range of 5.6-6.9 mmol/l. Future studies should examine the association of IFG with cardiovascular outcomes, but for diabetes risk our study supports the use of the IFG cut-point at 6.1 mmol/l.     

Personality traits of agreeableness and extraversion are associated with ADH4 variation.

BACKGROUND: Personality traits are associated with substance dependence (SD); genetic factors may influence both. Strong associations between ADH4 variation and SD have been reported. We aimed to investigate the relationship between ADH4 variation and personality traits in the present study. METHODS: We assessed dimensions of the five-factor model of personality in 243 subjects with SD (175 European Americans [EAs] and 68 African Americans [AAs]) and 296 healthy control subjects (256 EAs and 40 AAs). We also genotyped 7 ADH4 markers (spanning the locus) and 38 unlinked ancestry-informative markers in these subjects. The relationships between the diplotypes, alleles, and genotypes at ADH4 and personality traits were examined using multivariate analysis of covariance (MANCOVA), controlling for potential confounders. RESULTS: Generally, SD patients, older individuals, and male subjects scored higher on neuroticism and lower on other personality factors. Personality factors were associated with the diplotypes. The allele A or genotype A/A of single nucleotide polymorphism (SNP)6 (rs1800759 at the gene promoter) was significantly associated with agreeableness scores. There were associations between extraversion and SNP1 (hcv2033010 at the 3' end) and SNP2 (rs1042364 in exon 9) in subjects with higher conscientiousness scores. CONCLUSIONS: The personality traits of agreeableness and extraversion are related to ADH4 polymorphism. Among the ADH4 markers that appear to predispose to certain personality traits, the functional variant rs1800759 (SNP6) in the promoter region is most important. We conclude that personality traits and SD have a partially overlapping genetic basis.     

维甲酸硅油的视网膜毒性实验研究

目的：了解维甲酸硅油对视网膜是否产生毒性。 方法：12只新西兰白兔的24只眼，随机分为3组，行气体压迫玻璃体手术3天后，分别向玻璃体腔内注入硅油(4只眼)、5μg/ml维甲酸硅油(10只眼)、10μg/ml维甲酸硅油(10只眼)各
0.5m1，用检眼镜、光漳和电镜检查来观察视网膜变化情况。 结果：注入硅油28天后，未发现各浓度的维甲酸硅油对视网膜产生毒性作用。结论：浓度为5、10μg/ml的维甲酸硅油注入玻璃体腔4周，对视网膜不产生毒性作用。 （中华眼底病杂志，1997，13：81-82）