钉螺感染目平外睾吸虫的分泌物及其对杀灭不同时间再感染日本血吸虫幼虫的进一步观察

目的 湖北钉螺(Oncomelania hupensis)先感染目平外睾吸虫(Exorchis mupingensis)虫卵后,再间隔不同时间感染日本血吸虫(Schistosoma japonicum)毛蚴,观察螺体分泌物的强度对血吸虫幼虫损害和被杀灭情况的关系。方法 钉螺感染目平外睾吸虫后分别于21 d、37 d、55 d、70 d和85 d再感染血吸虫毛蚴。钉螺经双重感染后4-82 d, 作钉螺整体连续埋蜡切片、染色制片和全片观察,并记录血吸虫幼虫残体数。结果与结论 单独感染外睾吸虫的钉螺,和两吸虫感染间隔时间为21-85 d的钉螺,螺体都产生大量血淋巴细胞和分泌物,它们会围攻再侵入的日本血吸虫早期幼虫并侵入其体内,血吸虫幼虫结构发生异常、停止发育直至死亡。两种吸虫双重感染的间隔时间愈长,螺体血淋巴细胞数随时间增加而逐渐减少;而螺体分泌物不断增多,并见于血吸虫幼虫残骸内,螺体攻击血吸虫幼虫的效力愈强。这现象在单独感染日本血吸虫的钉螺体内未见到。     

日本血吸虫幼虫在先感染外睾吸虫后不同时间钉螺体内被生物控制效果的比较

摘要：前此实验显示：21d外睾吸虫阳性钉螺能使再侵入的全部血吸虫幼虫发育停留在异常早期母胞蚴阶段〔1 3〕。本文实验比较观察了感染外睾吸虫后不同时间（21d、35d、55d、70d及85d）的钉螺对再侵入的日本血吸虫幼虫生物控制的情况,发现外睾吸虫和血吸虫双重感染的钉螺,两者间隔时间愈长,后侵入的血吸虫幼虫被击毁程度愈强（图1 20）;不同间隔时间双重感染的各组实验钉螺,血吸虫幼虫感染率及幼虫侵入率如下：间隔21d,75%(39/52)和25.5%（398/1 560);间隔37d,77.8%（21/27）和 35.6%(299/840);间隔55d,44.4%（8/18）和11.9%(19/160);间隔70d,100%（15/15）和10.6%(143/1 350);间隔85d,43.3%（13/30）和5.8%(66/1 140)。     

日本血吸虫幼虫在钉螺及感染外睾吸虫钉螺发育的比较

湖北钉螺先感染外睾吸虫后再感染日本血吸虫,血吸虫幼虫在其体内被击杀(唐崇惕等,2008;2009),本文用日本血吸虫毛蚴分别接触已感染外睾吸虫21d的钉螺和阴性钉螺,观察血吸虫幼虫在此2组实验钉螺体内发育情况。从感染外睾吸虫钉螺再感染血吸虫的28个(73.7%)阳性螺,查获4～82d血吸虫幼虫共300条(侵入率26.74%),全部虫体结构异常停留在早期母胞蚴阶段。从单独感染血吸虫的25粒(69.4%)阳性螺,查获5～61d正常血吸虫母胞蚴67条(侵入率13.96%)和许多不同发育期子胞蚴,感染后75d阳性螺含血吸虫成熟子胞蚴和尾蚴。单独感染血吸虫钉螺的血淋巴细胞增生情况与双重感染外睾吸虫和血吸虫的钉螺存在差异。     

湖北钉螺被目平外睾吸虫与日本血吸虫不同间隔时间感染后分泌物的检测与分析

观察被目平外睾吸虫和日本血吸虫双重感染钉螺后钉螺体内外分泌物及其血吸虫幼虫被击毁的关系。方法 观察钉螺感染外睾吸虫21 d、37 d、55 d、70 d和85 d后再感染血吸虫,经482 d后,取钉螺软体组织作埋蜡连续染色制片。结果与结论 无论单独感染目平外睾吸虫或两种吸虫双重感染,均可在螺软体发现多种分泌物,随时间延长分泌物数量逐渐增多。螺体内含小细胞核的分泌物和螺副腺细胞都出现在各时期的血吸虫残骸体内。     

先感染外睾吸虫的钉螺其分泌物和血淋巴细胞对日本血吸虫幼虫的反应

单独感染外睾吸虫的湖北钉螺,螺体分泌物和血淋巴细胞剧烈增加;螺体表分泌物含大小不等颗粒及晶体状物, 体内分泌物为金黄色或褐色小颗粒,各颗粒团附近均有极小细胞核。双重感染外睾吸虫和日本血吸虫的钉螺,体内外分泌物和血淋巴细胞等产物同样大量产生;体内分泌物颗粒及其附近小细胞核、3种血淋巴细胞及副腺细胞,出现在血吸虫幼虫周围并进入虫体内;所有血吸虫幼虫结构异常,停止发育并死亡。阴性钉螺和单独感染日本血吸虫的钉螺,它们体内外分泌物及血淋巴细胞的数量均少;分泌物颗粒和血淋巴细胞虽有在血吸虫幼虫附近,但都没有进入虫体内。     

日本血吸虫幼虫在钉螺体内发育起点温度的研究

目的　研究环境温度对血吸虫幼虫在钉螺体内生长发育进程的影响程度。　方法　采集无血吸虫感染的钉螺,以钉螺与毛蚴1∶20比例感染,感染后置于30℃、27℃、24℃、21℃和18℃环境中饲养,计算钉螺体内血吸虫的尾蚴开放前期和发育速度,分析尾蚴开放前期和发育速度与环境温度间的相关关系。　结果　21℃、24℃、27℃、30℃时血吸虫的尾蚴平均开放前期分别为(128.89±16.05)d、(95.00±21.03)d、(71.93±12.74)d和(62.74±14.19)d。尾蚴开放前期与环境温度的回归方程为y=730.68x-0.8918(r=0.9976,P<0.01)。血吸虫发育速度与环境温度的回归方程为y=0.0235ln(x)-0.0639(r=0.9973,P<0.01)。从此方程中推算出日本血吸虫幼虫在钉螺体内的发育起点温度为15.17℃±0.43℃。　结论　环境温度降低,钉螺体内血吸虫幼虫发育速度减慢。     

血水草生物碱杀螺、灭蚴作用的研究

目的研究血水草生物碱(ECA)杀灭钉螺及日本血吸虫尾蚴的作用。方法观察实验室及现场浸泡杀螺效果;钉螺接触药物上爬情况;浸泡杀螺卵效果;浸杀尾蚴防护血吸虫感染的作用。结果浸泡72h钉螺死亡率100％的血水草生物碱溶液的浓度及温度分别为:1.25mg/L,30℃;2.5 mg/L、5 mg/L、10 mg/L均为25℃。水温 26℃～28℃现场灭螺10mg/L,72h钉螺死亡率84％;20 mg/L,72h死亡率达92％。5mg/L溶液螺卵浸泡72h孵出率为0％～10％。5mg/L ECA溶液明显抑制钉螺上爬,20mg/L时钉螺静止不动。结论血水草有杀灭钉螺、螺卵及日本血吸虫尾蚴的作用,是一种有研究前景的植物杀螺、灭蚴剂。     

钉螺感染日本血吸虫后酸性磷酸酶含量变化

目的 观察钉螺感染日本血吸虫后酸性磷酸酶(ACP)含量的变化.方法 以软组织挤压法获取感染性钉螺与阴性钉螺血淋巴细胞涂片,分别对2组钉螺血淋巴细胞进行ACP组织化学染色,用显微镜观察其活性变化.结果 感染性钉螺淋巴细胞中ACP含量增加,明显高于阴性钉螺.结论 ACP可能在钉螺感染日本血吸虫毛蚴的防御中发挥作用.     

日本血吸虫幼虫寄生对钉螺生存影响的研究

目的　了解日本血吸虫幼虫寄生对湖北钉螺生存的影响程度。方法　采集安徽贵池江滩无血吸虫感染的钉螺 ,在室内进行人工感染 ,将获得的感染性钉螺和对照组阴性钉螺同时放回现场环境饲养 ,每间隔 10 d观察钉螺生存情况 ,记录不同时间钉螺的存活率和死亡率 ,用动物生存寿命表法计算钉螺被血吸虫寄生后在现场环境中期望生存时间的变化。结果　在现场自然环境中 ,有血吸虫寄生钉螺的死亡高峰为 6 0～ 70 d时间段 ,推算期望生存时间为 6 3.4 6 d,最长生存时间为135 d;无血吸虫寄生钉螺的死亡高峰为 80～ 90 d时间段 ,推算期望生存时间为 83.5 4 d,最长生存时间为 15 5 d。感染了血吸虫的钉螺比无血吸虫感染的钉螺期望生存时间缩短了 2 4 .0 4 %。结论　感染了血吸虫的钉螺在自然环境中的死亡率增高 ,生存时间缩短     

有螺无病地区钉螺与日本血吸虫相容性的研究

目的 研究安徽省宁国市有螺无病地区钉螺与日本血吸虫的相容性,探索有螺无病地区形成的原因.方法 采集宁国市有螺无病地区钉螺600只,随机分为2组,每组300只.在实验室条件下以本省日本血吸虫毛蚴进行钉螺群体感染,两组钉螺与毛蚴比例分别为1:20和1:40.以相同方法感染铜陵县的肋壳钉螺和泾县的光壳钉螺作为对照.感染后将钉螺置于室内22～24℃温度下饲养90d.观察各组钉螺感染率和死亡情况.结果 在1:20组和1:40组中,宁国市有螺无病地区钉螺均未能被日本血吸虫成功感染,而铜陵县的肋壳钉螺和泾县的光壳钉螺均感染成功.至观察期结束时,无论是自然死亡率还是感染后死亡率,铜陵县的肋壳钉螺均显著低于宁国市有螺无病地区钉螺和泾县的光壳钉螺(均P＜0.05),而后两地钉螺死亡率差异无显著性(P＞0.05).结论 当地钉螺与日本血吸虫不相容可能是宁国市有螺无病地区形成的主要原因之一.     

Research and Evaluation of the Influence of the Construction of the Gate and the Influence of the Piston Velocity on the Distribution of Gases into the Volume of the Casting

Distribution of gasses to the cast volume and volume of pores can be maintained within the acceptable limits by means of correct setting of technological parameters of casting and by selection of suitable structure and gating system arrangement. The main idea of this paper solves the issue of suitability of die casting adjustment—i.e., change of technological parameters or change of structural solution of the gating system—with regards to inner soundness of casts produced in die casting process. Parameters which were compared included height of a gate and velocity of a piston. The melt velocity in the gate was used as a correlating factor between the gate height and piston velocity. The evaluated parameter was gas entrapment in the cast at the end of the filling phase of die casting cycle and at the same time percentage of porosity in the samples taken from the main runner. On the basis of the performed experiments it was proved that the change of technological parameters, particularly of pressing velocity of the piston, directly influences distribution of gasses to the cast volume.     

Weighing the QT Intervals with the Slope or the Amplitude of the T Wave

Objective: The reproducibility of QT interval measurements is low, even for the mean QT interval based on the standard ECG. In this study we analyzed whether the reproducibility of the mean weighed QT interval was better than the simple mean QT interval. The weighing was based on the amplitude of the T wave or the slope of the steepest tangent on the terminal part of the T wave. Material and methods: 12‐lead ECGs of 130 postmyocardial infarction patients were obtained. The QT intervals were measured by the tangent‐method on two occasions by the same observer Mismatch QT intervals were defined as QT intervals that were measured at only one occasion. Sixteen ECGs were rejected. The data were split into 34 and 80 ECGs for optimization and validation of the weighing, respectively. The weighed QT dispersion was calculated as the weighed mean of the three longest minus the weighed mean of the three shortest QT intervals. Results: Weighing with the slope increased the reproducibility by 41% (P = 3 10^‐6), but weighing with the amplitude reduced it by 20% (P = 0.02). However, if measurements with errors above 75 ms were rejected, weighing with the slope or the amplitude increased the reproducibility with 26% and 20% (P = 0.02), respectively. Weighing did not change the reproducibility of the weighed QT dispersion. Conclusion: Weighing with the slope improved the reproducibility of the mean weighed QT interval. However, if measurements with errors above 75 ms were rejected, weighing with the amplitude also increased the reproducibility. Weighing did not change the reproducibility of the weighed QT dispersion. Weighing is particularly efficient at reducing the negative impact of mismatch QT intervals on the reproducibility. A.N.E. 2002;7(1):4–9     

县级以下综合医疗机构医务人员对现代结控知识的认识现状调查

目的本文旨在了解医务人员现代结控知识掌握的现状及培训效果?方法于培训前后进行问卷调查,内容包括:病例发现?结核病诊断及化疗?结果培训前疫情报告和转诊,回答正确者占75.2%?71.7%;对临床表现?查痰和诊断依据,回答正确者占83.5%?42.5%?40.8%;抗痨药物?用药方法?化疗原则?短化方案?短化疗程?治愈标准六项,回答正确者占58%?14.4%?20.8%?9.2%?17%?24.3%?培训后再次调查发现,90%以上医务人员对现代结控基本知识已掌握?结论各级医务人员现代结控知识是很贫乏的,因此,对其进行系统培训是极为必要的,此项工作省时?省力?投入少,可收到事半功倍的效果。     

大骨节病病区水,粮实验对动物的骨和软骨中化学元素组成的影响

用质子激发 X 线荧光分析方法(PIXE)测定了大骨节病病区和非病区的水、粮以及用该水粮喂养的大白鼠的肋软骨和硬骨中22种化学元素的含量。结果发现水粮中存在差异的元素反应在用该水粮喂养的大白鼠的骨、软骨中也存在差异,含量都低的元素有 P、Mn、Cu、As、Zn。都高的有铅。其中锌低在水、粮、硬骨和软骨中都完全一致呈非常显著性差异(p<0.01)。提示病区水、粮中化学元素对骨质的影响不是单一元素缺乏或过多所致,而是多种元素的复合因素。     

高胆红素血症对肿瘤标志物测定的影响探讨

目的探讨高胆红素血症对Ca19-9、Ca24-2和CEA检测的影响.方法对320例胆管、胆囊良恶性疾病病人,15例胆囊炎病人的胆汁和血清以及10例肝硬化、10例黄疸肝炎病人进行Ca19-9、Ca24-2和CEA检测.结果在良性胆管、胆囊疾病中,Ca19-9的假阳性最高;在胆红素增高的良性疾病中,Ca19-9假阳性率达46.7%;15例胆汁和血清以及10例肝硬化和10例黄疸肝炎病人中,Ca19-9的假阳性率分别为93%、20%、80%和80%.结论高胆红素血症对Ca19-9检测影响最明显,胆囊、胆管良恶性疾病鉴别时,以Ca24-2和CEA检测为佳.     

Assessment of the Soft-Tissue Seal at the Interface between the Base of the Fixed Denture Pontic and the Oral Mucosa

Fixed dentures (bridges) are often selected as a treatment option for a defective prosthesis. In this study, we assess the contact condition between the base of the pontic and oral mucosa, and examine the effect of prosthetic preparation and material biocompatibility. The molars were removed and replaced with experimental implants with a free-end type bridge superstructure after one week. In Experiment 1, we assessed different types of prosthetic pre-treatment: (1) the untreated control group (Con: mucosa recovering from the tooth extraction); (2) the laser irradiation group (Las: mucosa recovering after the damage caused by a CO₂ laser); and (3) the tooth extraction group (Ext: mucosa recovering immediately after the teeth extraction). In Experiment 2, five materials (titanium, zirconia, porcelain, gold-platinum alloy, and self-curing resin) were placed at the base of the bridge pontic. Four weeks after the placement of the bridge, the mucosa adjacent to the pontic base was histologically analyzed. In Experiment 1, the Con and Las groups exhibited no formation of an epithelial sealing structure on the pontic base. In the Ext group, adherent epithelium was observed. In Experiment 2, the sealing properties at the pontic interface were superior for titanium and the zirconia compared with those made of porcelain or gold-platinum alloy. In the resin group, a clear delay in epithelial healing was observed.