次声作用后大鼠下丘脑血管紧张素Ⅱ含量的改变

目的 :观察次声作用后大鼠下丘脑血管紧张素 （Ang ）含量的变化。方法 :用 16 Hz,（130 d B和 90 d B）次声连续作用 1,7,14,2 1次 ,2 h/次。每月 1次。分别于作用后 0 .5 ,6 ,12 ,18,2 4h观察大鼠下丘脑 Ang 含量。结果 :130 d B次声作用 1,14,2 1次和 90 d B次声作用 7,2 1次后 ,大鼠下丘脑 Ang 含量均经历升高 ,下降 ,复呈升高的动态变化过程。 130 d B次声作用 7次后大鼠下丘脑 Ang 含量呈持续性升高。 90 d B次声作用 1,14次后 ,大鼠下丘脑 Ang 含量呈升高和下降的单峰曲线 ,且 14次组于次声停止作用后 12 h已与对照组之间的差异无显著性意义。结论 :不同声强和作用次数的次声 ,对大鼠下丘脑 Ang 含量的影响呈波动性改变。     

8Hz、90dB次声对一氧化氮分泌和血管内皮生长因子表达的影响

目的 :测定 8Hz、90 d B次声多次暴露后大鼠血浆一氧化氮 （NO）的含量变化及内皮生长因子 （VEGF）表达的改变。方法 :用 8Hz、90 d B的次声连续作用大鼠 1、7、14、2 1、2 8d,每天 2 h,测定大鼠血浆 NO含量和 VEGF表达的变化。结果 :次声暴露 1、7d,大鼠血浆 NO含量无变化 ,14、2 1d时降低 （P<0 .0 5） ,2 8d时恢复正常 （P>0 .0 5） ;在次声暴露期与对照组比较 ,VEGF表达增强 （P<0 .0 1）。结论 :次声可引起大鼠血浆 NO分泌的变化及 VEGF表达改变 ,其与次声暴露的时间和量有关     

补肾益精药固真方对老年大鼠肾上腺髓质功能的调节作用

利用高效液相色谱——电化学检测法(HPLC—EC)观察了老年大鼠肾上腺髓质功能的变化及补肾益精药固真方对其影响。结果表明,老年大鼠肾上腺髓质中肾上腺素(E)、去甲肾上腺素(NE)含量显著高于青年组(P<0.01及P<0.001),但E与NE含量之比低于青年组(P<0.05)。固真方能进一步升高E含量,并调整E/NE比值至正常范围。这提示大鼠肾上腺髓质功能随增龄呈代偿性增高,补肾益精药固真方能增强老年大鼠肾上腺髓质的代偿功能,调整E/NE比值,对维持老年大鼠内环境的稳定及提高对外环境的适应具有重要意义。     

长期高血浆去甲肾上腺素对兔心室肌电生理的影响

探讨长期高血浆去甲肾上腺素(NE)对兔心室肌电生理的影响。取成年新西兰大耳白兔30只,雌雄不拘,随机等分为3组,分别给予腹腔注射NE1.0mg/kg、0.5mg/kg和生理盐水1ml,一日两次,连续15天,分别作为NE高、低剂量组和对照组。利用自制复合电极同步记录电刺激前后左室内、中、外3层心肌单向动作电位(MAP)及心电图,观察比较3组MAP复极90%的时程(MAPD90)、跨壁复极离散度(TDR)、后除极及室性心律失常的诱发情况。结果:TDR及3层心肌的MAPD903组之间无差异。NE高、低剂量组中层心肌的MAP图形2期拱顶呈消失趋势;程序刺激下NE高剂量组早期或延迟后除极及室性心律失常发生率较对照组均明显增加(P<0.05),但无持续性室性心动过速、心室扑动、心室颤动发生;NE低剂量组仅频发或成对室性早搏发生率与对照组差异具有显著性,后除极和非持续性室性心动过速发生增加,但无显著性差异。结论:长期高血浆NE易诱发室性心律失常的原因可能与心室肌后除极的发生率升高及2相折返的形成有关。     

冠心病患者血浆HA和NE变化及临床意义

本文测定了37例冠心病患者和35例正常人(对照组)血浆组胺(HA)和去甲肾上腺素(NE)含量,发现冠心病患者测值均显著高于对照组,其中急性心肌梗塞(AMI)组HA值最高,并较心绞痛组升高显著;冠心病缺血发作缓解后,HA值下降较NE显著,伴心律失常者HA值显著高于无心律失常者.认为HA升高与心肌缺血有关.     

比索洛尔对慢性心力衰竭大鼠心肌β_1肾上腺素能受体及心功能的调节作用

目的研究比索洛尔对腹主动脉结扎所致慢性心力衰竭大鼠β_1肾上腺素能受体(β_1-AR)心功能的调节作用。方法 SD 大鼠40只,随机分为4组,即腹主动脉缩窄(COA)组;COA+比索洛尔组;假手术组;假手术+比索洛尔组。采用超声心动图和心室插管法评估心功能,ELISA_法检测各组大鼠血浆去甲肾上腺素(NE)水平,RIA 法检测心肌腺苷酸环化酶(AC)活性,通过 RT-PCR 检测心肌β_1-AR、β肾上腺素能受体激酶1(β-ARK1)和 Gi 蛋白 mRNA 的表达变化,Western blot 检测β_1-AR 蛋白水平的表达变化。结果 COA 组大鼠心功能恶化,血浆 NE 水平明显升高,β_1-AR mRNA 表达减少、β-ARK1和 Gi 蛋白 mRNA 表达增加,β_1-AR 的蛋白水平表达减少,AC 活性明显下降;比索洛尔明显改善大鼠心功能[射血分数:COA+比索洛尔组:(66.7±8.4)%比 COA 组:(43.3±7.7)%,P<0.05],降低血浆 NE 水平[COA+比索洛尔组:(570.2±41.2)pg/mL 比 COA 组:(908.24±75.10)pg/mL,P<0.05],增高...     

慢性间歇性低氧对大鼠血压和交感神经活动的影响

目的研究慢性间歇性低氧对大鼠血压和交感神经活动的影响。方法将雄性SD大鼠随机分为正常对照组和慢性间歇性低氧模型组(CIH),每组20只,分别采用无创套尾法监测大鼠尾动脉收缩压(SBP)随间歇性低氧时间的变化,在体记录大鼠的平均动脉压(MAP)和肾交感神经活动(RSNA),以及采用ELISA检测大鼠血浆中去甲肾上腺素(NE)的水平。结果间歇性低氧15 d后,CIH组SBP、MAP和RSNA较对照组明显升高;CIH组大鼠血浆中NE的含量较对照组明显升高(均P<0.05)。结论慢性间歇性低氧可引起大鼠血压升高和交感神经活动过度增强。     

低声压级水平次声对心肌梗死大鼠心肌纤维化的影响及机制研究

目的:观察次声对心肌梗死后大鼠心肌纤维化的影响及相关机制研究。方法:将30只SD大鼠随机分为3组,即假手术组、心肌梗死组及次声治疗组,每组10只。采用低声压级水平次声对心肌梗死大鼠治疗1周(2次/d,0.5 h/次),观察心肌胶原和血浆NO和血管紧张素-Ⅱ(AngⅡ)及大鼠心功能的变化。结果:与心肌梗死组大鼠比较(未治疗组),次声治疗组大鼠心肌胶原表达明显减少,血浆NO含量显著增加(P0.01),血浆AngⅡ含量显著降低(P0.01),心功能明显改善(P0.01)。结论:低声压级水平次声治疗能够明显减轻心肌梗死后大鼠心肌纤维化,其作用可能与血浆NO及AngⅡ含量变化有关。     

低声压级水平次声对心肌梗死大鼠心功能的影响及机制

目的: 观察次声对心肌梗死大鼠心功能的影响及相关的机制。方法: 将30只SD大鼠随机分为3组,即假手术组（对照组）、心肌梗死组及次声治疗组,每组10只。采用次声治疗仪对心肌梗死大鼠进行治疗1周（2次/d,0.5 h/次）, 观察心肌细胞超微结构的改变,血浆NO和内皮素-1（ET-1）水平的变化以及大鼠心功能的变化。结果: 与心肌梗死组大鼠比较,次声治疗组大鼠心肌超微结构损伤减轻,血浆NO含量增加（P<0.01）,血浆ENT-1含量减少（P<0.01）,心功能明显改善（P<0.01）。结论: 低声压级水平次声治疗能够显著改善心肌梗死后大鼠心脏功能。     

老年高血压病患者血浆5-羟色胺等物质的变化及其意义

对40例老年高血压病(EH)患者、26例中年EH患者、50例健康人的血浆中5-羟色胺(5-HT)、5-羟吲哚乙酸(5-HIAA)、去甲肾上腺素(NE)含量的观察结果发现,老年和中年EH患者5-HT、5-HIAA、NE值均明显高于健康组,老年组5-HT又高于中年组,老年和中年EH患者5-HT与平均动脉压均呈正相关性。5-HT的升高与NE的下降呈负相关性。老年舒张期EH者比单纯收缩期EH者5-HT值升高明显,EH并发冠心病时5-HT增高尤为显著。     

胰岛素瘤的解剖分布特点分析

目的胰岛素瘤是最常见的胰腺神经内分泌肿瘤，因其临床表现多样，导致诊断困难。影像学诊断尤其是超声内镜(EUS)在胰岛素瘤的诊断中起着重要作用，拥有较高的敏感性和特异性。本研究拟通过明确胰岛素瘤的解剖分布特点，以期有助于提高影像学的诊断准确率和降低漏诊率，尤其是在教育和培训实践中对于EUS的学习者更具有指导价值。 方法回顾性分析解放军总医院第一医学中心病案资料数据库1993年1月至2019年11月经外科手术、病理确诊为胰岛素瘤的患者的临床资料，检索方法采取搜索术后病理诊断为"胰岛素瘤"的病例，通过查阅病例的方法，提取出胰岛素瘤的大小和解剖分布等数据，进一步分析其特点。 结果共检索到确诊为胰岛素瘤的患者116例，其中，男45例、女71例，年龄13～76岁，平均年龄(44.4±14.85)岁。胰岛素瘤单发110例(94.8%)、多发6例(5.2%)。位置分布：头颈部46例(39.7%)，单发45例、多发1例；体尾部68例(58.6%)，单发65例、多发3例；全胰腺多发2例(1.7%)。病变大小特点：最大径0.4～3.4 cm，平均大小(1.53±0.58)cm。≤1 cm 29例、>1 cm而≤1.5 cm41例、>1.5 cm而≤2.0 cm28例，≤3 cm 15例，>3 cm 3例。年龄与肿瘤的大小相关，≤44岁患者肿瘤平均大小为(1.36±0.51)cm、>44岁患者肿瘤平均大小为(1.70±0.60)cm，P<0.05。头颈部的肿瘤大于体尾部的肿瘤，头颈部肿瘤平均大小(1.66±0.63)cm，体尾部(1.42±0.52)cm，P<0.05。 结论胰岛素瘤在胰腺体尾部较头颈部更好发；绝大多数单发，但可以全胰腺多发；多数小于1.5 cm，肿瘤的大小与患者年龄和肿瘤的解剖分布相关。     

Pathogenesis of carcinoma of the papilla of Vater

Most adenomas and carcinomas of the small intestine and extrahepatic bile ducts arise in the region of the papilla of Vater. In familial adenomatous polyposis (FAP) it is the main location for carcinomas after proctocolectomy. In many cases symptoms due to stenosis lead to diagnosis at an early tumor stage. In about 80%, curative intended resection is possible. Operability is the most relevant prognostic factor. Most ampullary carcinomas resp. carcinomas of the papilla of Vater develop from adenomatous or flat dysplastic precursor lesions. They can be sited in the ampulloduodenal part of the papilla of Vater, which is lined by intestinal mucosa. They also can develop in deeper parts of the ampulla, which are lined by pancreaticobiliary duct mucosa. Intestinal-type adenocarcinoma and pancreaticobiliary-type adenocarcinoma represent the main histological types of ampullary carcinoma. Furthermore, there exist unusual types and undifferentiated carcinomas. Many carcinomas of intestinal type express the immunohistochemical marker profile of intestinal mucosa (keratin 7?, keratin 20+, MUC2+). Carcinomas of pancreaticobiliary type usually show the immunohistochemical profile of pancreaticobiliary duct mucosa (keratin 7+, keratin 20?, MUC2?). Even poorly differentiated carcinomas, as well as unusual histological types, may conserve the marker profile of the mucosa they developed from. These findings underline the concept of histogenetically different carcinomas of the papilla of Vater which develop either from intestinal- or from pancreaticobiliary-type mucosa of the papilla of Vater. Molecular alterations in ampullary carcinomas are similar to those of colorectal as well as pancreatic carcinomas, although they appear at different frequencies. In future studies, molecular alterations in ampullary carcinomas should be correlated closely with the different histologic tumor types. Consequently, the histologic classification should reflect the histogenesis of ampullary tumors from the two different types of papillary mucosa.     

Demonstration of the mechanism of action of biguanides

Summary Palmitic acid oxidation in rat diaphragm homogenate is depressed by biguanide concentrations that are still incapable of inhibiting oxidative phosphorylation. Glucose oxidation is not directly effected by the same biguanide concentrations: however, the inhibitory effect of palmitic acid on glucose oxidation is partly removed by biguanides. Inhibition of fatty acid oxidation, which accounts for most of the metabolic effects caused by these drugs, can be regarded as the fundamental mechanism of action of biguanides. There is some evidence suggesting that these drugs might interact with carnitine, thus preventing long-chain fatty acids from being transported across the mitochondrial membrane to the site of oxidation. Traduzione a cura degli AA.     

Lack of correlation of degree of villous atrophy with severity of clinical presentation of coeliac disease

BACKGROUND AND AIM: Both the clinical presentation and the degree of mucosal damage in coeliac disease vary greatly. In view of conflicting information as to whether the mode of presentation correlates with the degree of villous atrophy, we reviewed a large cohort of patients with coeliac disease. PATIENTS AND METHODS: We correlated mode of presentation (classical, diarrhoea predominant or atypical/silent) with histology of duodenal biopsies and examined their trends over time. RESULTS: The cohort consisted of 499 adults, mean age 44.1 years, 68% females. The majority had silent coeliac disease (56%) and total villous atrophy (65%). There was no correlation of mode of presentation with the degree of villous atrophy (p=0.25). Sixty-eight percent of females and 58% of males had a severe villous atrophy (p=0.052). There was a significant trend over time for a greater proportion of patients presenting as atypical/silent coeliac disease and having partial villous atrophy, though the majority still had total villous atrophy. CONCLUSIONS: Among our patients the degree of villous atrophy in duodenal biopsies did not correlate with the mode of presentation, indicating that factors other than the degree of villous atrophy must account for diarrhoea in coeliac disease.     

血吸虫童虫生长发育及其机制的研究进展

血吸虫童虫是宿主免疫系统攻击的重要靶标,包括皮肤型、肺型和肝门型童虫。宿主分子对童虫生长发育具有重要作用。童虫生长发育机制包括免疫调节、信号转导、性别发育及凋亡等。肌动蛋白、组织蛋白酶、烯醇化酶和葡萄糖基转移酶等分子为血吸虫童虫生长发育的重要分子。本文对血吸虫童虫生长发育及其机制的研究进展做一综述。     

氯硝柳胺悬浮剂的毒性评价

目的评价氯硝柳胺悬浮剂的毒性，为现场大规模应用灭螺提供依据。方法按照中华人民共和国国家标准GB 15670-1995《农药登记毒理学试验方法》和鱼类毒性试验方法进行。结果经口、经皮肤的LDso雌、雄性大鼠均>5 000 mg/kg，经呼吸道的LCso雌、雄性大鼠均>5 000mg/m3，该药经口、经皮肤、经呼吸道毒性均属微毒类药物；兔眼用药后，观察期内无不良反应，对眼无刺激性；皮肤用药后对皮肤无刺激性。与氯硝柳胺原药、氯硝柳胺乙醇胺盐原药和氯硝柳胺乙醇胺盐可湿性粉剂相比，氯硝柳胺悬浮剂对鱼急性毒性最低。结论氯硝柳胺悬浮剂属微毒类药物，对鱼的毒性低于其乙醇胺盐可湿性粉剂，适合于现场应用。     

124例耐多药结核分枝杆菌基因突变特征分析

目的对临床分离的耐多药结核分枝杆菌相关基因的突变特征进行分析。方法对124例耐多药结核分枝杆菌以及50株敏感株的耐药相关基因(包括异烟肼inh A、kat G、oxyR-ahp C间隔区以及利福平rpo B)进行序列测定,分析其基因突变情况。结果异烟肼耐药inh A基因突变率为14.5%;kat G基因突变率为70.2%(87/124),主要位于315位;oxyR-ahp C间隔区突变率为15.3%;inh A、kat G两种基因同时突变率75.0%,三种基因同时突变率为89.5%。利福平rpo B基因突变的检出率高达95.2%,突变主要发生在531、526、516位点。结论我省耐多药菌异烟肼耐药相关基因最常见突变为kat G 315、inh A C-T(-15)、axyR-ahp C间隔区(-10)C-T,利福平为rpo B531、526、516。结合MDR-TB耐药相关基因的特征分析,可以建立一种快速、准确、特异的适合于我省的检测结核菌耐多药性的新方法。     

Assessment of quality of life of parents of children with juvenile chronic arthritis

The aim of the study was to assess the quality of life (QOL) and the psychological status of parents of children with juvenile chronic arthritis (JCA). The QOL, anxiety and depression of the parents of 28 children with JCA were evaluated and compared to those of the parents of 28 healthy children. Mothers of JCA children and mothers of healthy children reported similar QOL. The reported anxiety and depression levels were similar for mothers and fathers in both groups. The parents of children with pauciarticular-type JCA reported lower QOL and higher levels of anxiety and depression than the parents of children with other types, namely polyarticular and systemic JCA. These findings may be explained by the fact that the pauciarticular patients had shorter disease duration and were less frequently seen in the outpatient clinic. The QOL of mothers of children with JCA was found to be slightly impaired in the group of children with pauciarticular JCA. Future larger studies are needed to confirm these results, as the number of subjects in the three groups was rather low. Received: 26 September 2001 / Accepted: 8 February 2002     

Numerical Simulation of the Effect of Rate of Change of Glucose on Measurement Error of Continuous Glucose Monitors

Background

A 5-day in-patient study designed to assess the accuracy of the FreeStyle Navigator® Continuous Glucose Monitoring System revealed that the level of accuracy of the continuous sensor measurements was dependent on the rate of glucose change. When the absolute rate of change was less than 1 mg•dl⁻¹•min⁻¹ (75% of the time), the median absolute relative difference (ARD) was 8.5%, with 85% of all points falling within the A zone of the Clarke error grid. When the absolute rate of change was greater than 2 mg•dl⁻¹•min⁻¹ (8% of the time), the median ARD was 17.5%, with 59% of all points falling within the Clarke A zone.

Method

Numerical simulations were performed to investigate effects of the rate of change of glucose on sensor measurement error. This approach enabled physiologically relevant distributions of glucose values to be reordered to explore the effect of different glucose rate-of-change distributions on apparent sensor accuracy.

Results

The physiological lag between blood and interstitial fluid glucose levels is sufficient to account for the observed difference in sensor accuracy between periods of stable glucose and periods of rapidly changing glucose.

Conclusions

The role of physiological lag on the apparent decrease in sensor accuracy at high glucose rates of change has implications for clinical study design, regulatory review of continuous glucose sensors, and development of performance standards for this new technology. This work demonstrates the difficulty in comparing accuracy measures between different clinical studies and highlights the need for studies to include both relevant glucose distributions and relevant glucose rate-of-change distributions.     

Study of constancy of hydrogen-consuming flora of human colon

The constancy of the hydrogen consuming flora of the human colon was studied in 15 healthy subjects via two measurements obtained 18 to 36 months apart. Hydrogen disappearance rate and the major products of H₂-consuming bacteria, methane and sulfide, were measured during incubation of fecal homogenates with excess hydrogen and sulfate. In 11/15, the hydrogen consumption rate and the predominant hydrogen-consuming pathway (methanogenesis, sulfate reduction, or neither) remained constant. However, major shifts in these pathways were observed in four subjects, with two losing and two gaining the ability to produce methane. Methanogenesis was associated with the highest hydrogen consumption rate. This study demonstrates that clinically unrecognizable, major alterations of the colonic flora occur in healthy subjects. Understanding of the factors responsible for these alterations might allow for therapeutic manipulation of the colonic flora.Supported in part by the Department of Veterans Affairs and NIDDKD RO1 DK 13309-25.