万寿菊提取物改善老龄大鼠抗氧化功能的研究

目的研究万寿菊提取物（叶黄素）对D-半乳糖致衰老大鼠抗氧化能力的影响。方法用D-半乳糖注射Wistar雄性大鼠5个月，建立衰老模型。对衰老模型组、叶黄素组血清丙二醛（MDA）含量、肝脏匀浆MDA含量和血液超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH．Px）活性进行测定及比较。结果叶黄素组血清MDA含量和肝脏匀浆MDA含量均比衰老模型组有所降低，而血液SOD、GSH—Px酶活性有所升高（P〈0．01）。结论摄入适量万寿菊提取物可以有效地增强大鼠机体抗氧化能力，从而延缓D-半乳糖诱发的大鼠衰老。     

人工致衰老和自然衰老小鼠抗氧化能力改变的对比研究

目的 对比研究人工致衰老和自然衰老小鼠氧化水平和抗氧化能力的改变。方法 20只2月龄雄性小鼠，随机分为致衰老模型组和正常对照组；致衰老模型组每日皮下注射D-半乳糖100mg／kg，正常对照组每日皮下注射等量生理盐水，持续42d;自然衰老组为15月龄同种系雄性小鼠。以丙二醛(MDA)、一氧化氮(NO)含量以及超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH—Px)和一氧化氨合酶(NOS)活性等为指标，对比研究人工致衰老和自然衰老小鼠氧化水平和抗氧化能力的改变。结果 与正常对照组相比，D-半乳糖致衰老和自然衰老组小鼠血清、心、脑、肝、肺、肾等组织的MDA含量增加。血清GSH—Px活性以及血清、脑、肝、肺、肾等脏器的SOD活性降低;自然衰老组小鼠血清NO含量、NOS活性以及心脏SOD活性降低，而致衰老组血清NO含量以及NOS和心脏SOD活性无明显变化。结论 D-半乳糖致衰老小鼠氧化水平增加，抗氧化能力下降；但与自然衰老小鼠相比，仍存在一定差异。     

蜂胶黄酮对衰老模型小鼠脑组织抗氧化作用的影响

目的研究蜂胶黄酮对D-半乳糖致衰老小鼠神经细胞抗氧化作用。方法以D-半乳糖侧腹部注射小鼠,同时连续灌服蜂胶黄酮25d,分别检测小鼠脑组织超氧化物歧化酶（SOD）以及过氧化氢酶（CAT）的活性及丙二醛（MDA）的含量。结果蜂胶黄酮可使衰老模型小鼠脑组织中SOD、CAT活性明显增高,和衰老模型组相比具有显著差异（P〈0.01）;使脑组织MDA明显降低,和衰老模型组相比具有显著差异（P〈0.01）。结论蜂胶黄酮可有效地提高脑组织中抗氧化酶的活性,有效地增强小鼠机体抗氧化能力。     

卷丹水提物对D-半乳糖衰老模型小鼠的影响

目的观察卷丹水提物对D-半乳糖衰老模型小鼠的影响。方法建立D-半乳糖致小鼠衰老模型，以Y型电迷宫检测其学习记忆能力，分别采用黄嘌呤氧化酶法、TBA比色法测定大脑SOD活性和MDA含量，观察小鼠服用卷丹水提物后上述指标的变化。结果与D-半乳糖模型组相比，卷丹水提物低、中、高剂量均可显著提高衰老模型小鼠的学习记忆能力（P〈0．05或P〈0．01），显著增加D-半乳糖所致衰老模型小鼠大脑SOD活性、降低MDA含量（P〈0．05）。结论卷丹水提物能改善D-半乳糖所致衰老小鼠的多项体征。     

葛根素抗衰老作用实验研究

选择Wistar大鼠30只,其中20只用2％D-半乳糖制作亚急性衰老模型,随机分为衰老模型组和葛根素治疗组各10只,另外10只作为对照组。分别检测各组大鼠血清超氧化物歧化酶（SOD）、丙二醛（MDA）、谷胱甘肽过氧化物酶（GsH—Px）及脑组织中脂褐质（LPF）含量。发现与对照组比较,衰老模型组SOD、GsH—Px活性下降,MDA及LPF水平升高（P〈0．01）;与衰老模型组比较,葛根素治疗组SOD、GsH—Px活性升高,MDA及LPF水平下降（P〈0．01）。认为葛根素可显著提高亚急性衰老大鼠血清SOD、GsH-Px活性,降低MDA及脑组织中LPF水平,具有抗衰老作用。     

松花粉对亚急性衰老模型大鼠抗衰老作用的实验研究

目的通过对亚急性衰老大鼠模型血清超氧化物歧化酶（SOD）、丙二醛（MDA）、谷胱甘肽过氧化物酶（GSH—Px）和总抗氧化能力（T-AOC）的测定，观察大鼠精子数量、活动度和存活率的变化，从而探讨松花粉的抗衰老作用。方法D-半乳糖连续腹腔注射制作亚急性衰老大鼠模型，采用生物化学方法检测了各实验组血清中SOD、MDA、GSH—Px和T—AOC的含量；观察了大鼠精子数量、活动度和存活率的变化。结果D-半乳糖所致亚急性衰老大鼠模型组SOD活力、GSH—Px活力和T—AOC均明显下降，MDA含量明显上升，与正常对照组比较差异显著（P〈0．01）；而经松花粉给药后SOD活力、GSH-Px活力和T-AOC三者均有显著提高，MDA含量明显下降；松花粉可提高D-半乳糖所致亚急性衰老大鼠精子的数量、活动度和存活率。结论松花粉可显著提高亚急性衰老大鼠抗氧自由基的能力，提高精子的数量、活动度和存活率，具有延缓衰老的作用。     

鸡胚低分子提取物对D-半乳糖拟衰老小鼠线粒体DNA缺失突变的影响

目的 探讨鸡胚低分子提取物对D-半乳糖诱导的衰老小鼠线粒体DNA(mtDNA)缺失突变的影响.方法 采用D-半乳糖诱导制备衰老小鼠模型并用鸡胚低分子提取物处理.用聚合酶链反应技术和琼脂糖凝胶电泳检测mtDNA缺失片段,密度扫描技术对扩增片段进行相对定量.缺失片段构建质粒后,直接测序进行鉴定.结果 全部小鼠的肝、大脑皮质与海马组织内均存在4239 bp的mtDNA缺失片段.衰老模型鼠不同组织mtDNA缺失的相对百分含量均明显高于正常对照组(均为P%0.01),而鸡胚低分子提取物可明显降低模型鼠肝、大脑皮质与海马组织内mtDNA缺失的比例(均为P＜0.05).肝组织中mtDNA缺失的比例较大脑皮质和海马组织更高.结论 4239 bp的mtDNA缺失片段普遍存在于小鼠中,鸡胚的低分子提取物可以明显减少D-半乳糖拟衰老小鼠4239 bp的mtDNA缺失的发生.     

玉米黄质改善D-半乳糖致衰老大鼠抗氧化功能的研究

目的 研究玉米黄质对D-半乳糖致衰老大鼠抗氧化能力的影响。方法 用D-半乳糖注射Wistar雄性大鼠5月龄，建立衰老模型。对模型组、玉米黄质组肝脏、肾脏、心脏、脑和前列腺等脏器丙二醛（MDA）含最、超氧化物歧化酶（SOD）、谷胱甘肽过氧化酶（GSH—Px）活性进行测定及比较。结果 玉米黄质组各脏器MDA含量均比模型组有所降低，具有统计学意义（P〈0．01），而SOD、GSH-Px酶活性比模型组有所升高，具有统计学意义（P〈0．01）。结论 摄入玉米黄质可有效增强大鼠机体抗氧化能力，从而延缓D-半乳糖诱发的大鼠衰老。     

地锦草总黄酮对老化模型小鼠血清衰老指标的影响

目的探讨地锦草总黄酮（TFEH）对老化模型小鼠的抗衰老作用机制。方法D-半乳糖致亚急性衰老模型小鼠共40d,分为正常对照组、模型组、TFEH大、小剂量组,检测各组小鼠血清丙二醛（MDA）、超氧化物歧化酶（SOD）和谷胱甘肽过氧化物酶（GSH-Px）水平变化。结果TFEH能显著降低D-半乳糖致亚急性衰老模型小鼠血清MDA水平（P〈0.01）,能明显升高血清SOD、GSH-Px活性（P〈0.01）。结论TFEH可通过抗氧化作用而延缓衰老。     

大豆异黄酮对D-半乳糖致衰老模型小鼠抗氧化系统作用的实验研究

目的　研究大豆异黄酮 (ISO)对 D-半乳糖致衰老模型小鼠抗氧化系统的影响。方法　用 D-半乳糖诱导小鼠制成衰老模型 ,同时给予不同剂量的 ISO灌胃 4 w,测定脑匀浆超氧化物歧化酶 (SOD)、血清谷胱甘肽过氧化物酶 (GSH- Px)活力以及血清丙二醛 (MDA)含量。结果　与正常对照组相比 ,模型组小鼠脑组织 SOD活力和血清 GSH- Px活力明显降低 ,血清 MDA含量明显升高 ;不同剂量 ISO可不同程度的提高 SOD和 GSH-Px活力 ,降低血清 MDA含量。结论　 ISO对于衰老模型小鼠抗氧化系统功能具有一定的促进作用。     

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。     

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。     

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。     

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.