血水草生物碱杀灭钉螺的研究

目的探讨血水草生物碱在实验室不同温度下杀灭钉螺的效果.方法在实验室配制不同浓度的血水草生物碱溶液,观察在20、25、30℃时浸泡24、48、72、96 h的钉螺死亡率;观察杀螺卵效果;观察钉螺上爬率.结果浸泡72 h钉螺死亡率为100%的血水草生物碱溶液的浓度及温度分别为:1.25 mg/L、30℃;2.5、5、10 mg/L均为25℃.5 mg/L时能明显抑制钉螺上爬.螺卵在5 mg/L溶液浸泡72 h孵出率为0～10%.结论血水草生物碱有较好杀灭钉螺的效果,是一种有研究价值的植物灭螺剂.     

影响血水草生物碱灭螺效果相关因素的研究

目的探讨影响血水草生物碱（ECA）实验室和现场灭螺效果的相关因素。方法在实验室配置不同浓度的ECA溶液,20、25、30℃浸泡钉螺,观察浸泡24、48、72、96h钉螺死亡率;同时在现场观察不同浓度ECA在不同时间的浸泡灭螺效果。结果实验室浸泡灭螺试验结果显示,在不同浓度、时间和温度下钉螺死亡率有明显差异（P〈0.01）;在温度为30℃、浓度为1.25mg/L,或温度为25℃、浓度为2.5、5、10mg/L时,浸泡72h钉螺死亡率达100%。现场灭螺试验结果显示,在水温为26～28℃,浓度为10mg/L和20mg/L时,浸泡72h钉螺死亡率分别为84%和92%。logistic回归分析显示,浓度、作用时间及温度均为ECA灭螺效果的影响因素。结论影响ECA灭螺效果的因素包括浓度、温度和作用时间;随着浓度增加和浸泡时间的延长,灭螺效果增强。     

敌百虫杀灭血吸虫卵及钉螺的实验观察

目的：寻找杀灭血吸虫卵和灭螺的药物。方法：以敌百虫为实验组，氯硝柳胺乙醇胺盐可湿性粉剂为实验对照组，清水为空白对照组，在室内外进行浸杀和喷洒杀灭血吸虫卵和灭螺的实验。观察不同时间、不同浓度下虫卵和尾蚴、钉螺的死亡情况。结果：阳性兔粪中血吸虫在敌百虫1mg/L浓度中浸泡24h有明显的杀灭作用；在人粪液中浸杀48h有明显杀灭虫卵作用。敌百虫浓度在10mg/L时，用药3d后钉螺死亡率均达90％以上。结论：敌百虫有明显的杀灭血吸虫卵的作用。     

血水草生物碱联合氯硝柳胺杀螺增效作用研究

目的探讨血水草生物碱(ECA)与氯硝柳胺的联合杀螺增效作用。方法采用室内浸杀法,将不同浓度的氯硝柳胺溶液分别与不同浓度的ECA溶液复配成混合溶液,在25℃恒温条件下浸泡钉螺24、48h和72h,观察钉螺死亡情况。结果0.5mg/LECA分别与不同浓度的氯硝柳胺等量混合后,浸杀灭螺24、48、72h时,氯硝柳胺LC50由单独浸杀时的0.159、0.037、0.028mg/L降为合用后的0.100、0.029、0.016mg/L;而与1mg/LECA合用后,LC50则为0.083、0.025、0.009mg/L,其LC50均降低,增效比(SR)均>1;1.0mg/LECA与氯硝柳胺合用72h时,其SR为3.01。结论0.5、1.0mg/LECA与氯硝柳胺混合后对钉螺有较强的联合杀螺效果,对氯硝柳胺杀螺有增效作用。     

“浸螺杀”灭螺效果及毒性的研究

“浸螺杀”室内1mg/L浸杀钉螺48、72h的死亡率分别为73.3％和100.0％。现场1mg/L浸杀3d和5d的钉螺死亡率分别为90％和100％。室内1mg/L浸杀螺卵48、72h后第30d的孵出率为3.3％和0。能抑制钉螺活动和阻止上爬,药效稳定并具有持效作用。浸杀灭螺近期效果与五氯酚钠相仿,远期效果稍优于五氯酚钠。大面积应用效果较好。     

槟榔杀灭钉螺的效果观察

目的观察槟榔提取物杀灭钉螺的效果。方法采用室内浸杀法,对槟榔乙醇提取物的杀螺效果及抑制钉螺上爬情况进行观察。结果槟榔乙醇提取物浸泡钉螺24、48h和72h的LC50分别为60.9、26.9mg/L和16.3mg/L。浸泡24h时,12.5mg/L浓度明显抑制钉螺上爬,而25.0mg/L的上爬率为0。结论槟榔乙醇提取物具有较好的杀灭钉螺效果和抑制钉螺上爬作用,是一种有研究价值的植物杀螺剂。     

杀虫丁杀灭钉螺的室内和现场实验研究

目的 研究杀虫丁室内和现场的杀螺。方法 采用室内喷洒、浸杀和现场喷洒试验,研究杀虫丁的杀螺效果。浸泡钉螺观察钉螺逃逸情况。结果 25℃室内杀虫丁2mg/L浸泡钉螺48和1mg/L浸泡钉螺72h以上杀螺率在96.67以上,LC50为0.3970和0.2127mg/L。实验室喷洒杀螺率在78％以上,现场 洒杀螺率在86％以上。逃逸试验显示杀虫丁有抑制钉螺上爬作用。结论 杀虫丁杀螺效果好,可用于现场杀灭钉螺。但尚需研究其影响杀螺效果的影响因素。     

血水草生物碱杀灭日本血吸虫尾蚴实验

目的 探讨血水草生物碱杀灭日本血吸虫尾蚴的效果。方法 配制不同浓度的血水草生物碱水溶液，分别吸取各种浓度的药液100μl于载玻片上，观察不同时间尾蚴存活情况及小鼠感染情况。结果 药物浓度为2．5，5mg/L，接触药物60min，血吸虫尾蚴死亡率分别为97．71％和100％，药物浓度10，20mg/L，接触药物30min，血吸虫尾蚴无感染性。结论 血水草生物碱确有一定的杀灭血吸虫尾蚴的效果。     

氯硝柳胺悬浮剂浸杀钉螺螺卵和幼螺效果的研究

目的了解氯硝柳胺悬浮剂(SCN)杀灭钉螺螺卵、幼螺等不同生长发育阶段的效果。方法分别称取SCN和氯硝柳胺乙醇胺盐可湿性粉剂(WPN),采用实验室螺卵、幼螺浸杀法,并比较两者对杀灭螺卵和幼螺的不同效果。结果SCN0.25mg/L浸杀螺卵24h,螺卵死亡率为100%;WPN0.50mg/L浸杀24h,螺卵死亡率为100%。SCN浸杀螺卵24、48、72h的LC50值分别为0.0506、0.0496、0.0473mg/L;WPN浸杀螺卵24、48、72h的LC50值分别为0.1030、0.0962、0.0869mg/L。SCN和WPN0.25mg/L浸杀幼螺死亡率均为100%;SCN浸杀幼螺24、48、72h的LC50值分别为0.0625、0.0474、0.0442mg/L;WPN浸杀幼螺24、48、72h的LC50值分别为0.1088、0.0825、0.0825mg/L。结论氯硝柳胺悬浮剂对钉螺螺卵、幼螺均具有较好的杀灭作用。     

溴乙酸胺杀灭钉螺的现场实验观察

为进一步验证溴乙酰胺(特杀螺)杀灭钉螺的效果,进行了现场灭螺实验,钉螺校正死亡率1.5mg/L 浸泡48h为100％;喷洒2.0g/m~2 7d为92.6％;沿边药浸2.0g/m 48h达100％。与五氯酚钠相比,溴乙酰胺的上述剂量在现场无论是浸杀,喷洒和沿边药浸的杀螺校正死亡率均高于五氯酚钠10mg/L浓度,显示该药具有较好的杀螺作用。     

The immunoneuroendocrine role of melatonin

Abstract: A tight, physiological link between the pineal gland and the immune system is emerging from a series of experimental studies. This link might reflect the evolutionary connection between self-recognition and reproduction. Pinealectomy or other experimental methods which inhibit melatonin synthesis and secretion induce a state of immunodepression which is counteracted by melatonin. In general, melatonin seems to have an immunoenhancing effect that is particularly apparent in immunodepressive states. The negative effect of acute stress or immunosuppressive pharmacological treatments on various immune parameters are counteracted by melatonin. It seems important to note that one of the main targets of melatonin is the thymus, i.e., the central organ of the immune system. The clinical use of melatonin as an immunotherapeutic agent seems promising in primary and secondary immunodeficiencies as well as in cancer immunotherapy. The immunoenhancing action of melatonin seems to be mediated by T-helper cell-derived opioid peptides as well as by lymphokines and, perhaps, by pituitary hormones. Melatonin-induced-immuno-opioids (MHO) and lymphokines imply the presence of specific binding sites or melatonin receptors on cells of the immune system. On the other hand, lymphokines such as -γ-interferon and interleukin-2 as well as thymic hormones can modulate the synthesis of melatonin in the pineal gland. The pineal gland might thus be viewed as the crux of a sophisticated immunoneuroendocrine network which functions as an unconscious, diffuse sensory organ.     

Changes in connexin43, the gap junction protein of astrocytes, during development of the rat pineal gland

Abstract: The abundance of gap junctions between rat pineal astrocytes formed by connexin43 (Cx43) was studied during development. Levels and distribution of Cx43 were measured by immunoblotting and indirect immunofluorescence, respectively. The amount of Cx43 in cells located within the gland was low until about the 7th postnatal day and increased to adult values between the 14th and 21st days postpartum. Although astrocytes, recognized by their vimentin immunoreactivity, were scarce before birth, they were abundant by the 7th postnatal day suggesting that the low levels of Cx43 found at this age corresponded to a low expression of this protein. Localization of the immunoreactivity to Cx43 and vimentin showed a close correlation, indicating that mature or immature pineal astrocytes form gap junctions made of Cx43. Since Cx43 levels attained their adult values at about the time the innervation and the functional state of the gland reached maturity (2–3 weeks after birth), it is proposed that astrocyte gap junctions are involved in the function of the adult rat pineal gland.     

Conservative management of perforated duodenal diverticulum： A case report and review of the literature

Duodenal diverticula are a relatively common condition. They are asymptomatic, unless they become complicated, with perforation being the rarest but most severe complication. Surgical treatment is the most frequently performed approach. We report the case of a patient with a perforated duodenal diverticulum, which was diagnosed early and treated conservatively with antibiotics and percutaneous drainage of secondary retroperitoneal abscesses. We suggest this method could be an acceptable option for the management of similar cases, provided that the patient is in good general condition and without septic signs.     

Response of rat pineal melatonin to calcium, magnesium, and lithium is circadian stage dependent

Abstract: Herein we documented the response of pineal melatonin production to electrolytes known to be effective on pineal function in view of a possible circadian stage dependence. We studied the release of melatonin by perifused rat pineal glands at 2 different circadian stages corresponding to the middle of the light and dark periods, i.e., respectively, 7 and 19 HALO (Hours After Light Onset, L:D = 12:12). The initial efflux rates were, as expected, much higher in the perifusates of glands removed from rats sacrificed during the dark phase than of those removed during the light phase. After 3 hr of perifusion, melatonin release reached similar levels which were found constant up to the 8th hr of perifusion, whatever the circadian stage. Perifusion of the glands with physiological concentrations for the rat of calcium (5.2 mmol/1) and magnesium (1.34 mmol/1) resulted in a stimulatory effect on the pineal glands removed from rats sacrificed in the middle of the dark period (19 HALO), whereas no effects were observed on the pineal glands removed from rats sacrificed during the light (7 HALO). Lithium (0.28 and 0.55 mmol/1) was ineffective on melatonin release in pineal glands removed 7 and 19 HALO. Our results show differences in the initial efflux rates of melatonin and in the response of perifused pineal glands to calcium and magnesium according to the circadian stage.     

Presence of immunoreactive growth hormone and prolactin in the ovine pineal gland

Abstract: The use of antisera raised against bovine growth hormone (GH) and ovine prolactin (PRL) enabled the detection of related immunoreactive (ir) sequences of proteins in ovine pineal tissue. The isolation of PRL-like ir-material was accomplished using a 0.25 M ammonium sulphate (pH 5.5) extraction followed by ethanol precipitation, whereas the resulting 2.0 M ammonium sulphate (pH 7.0) precipitate contained a GH-like immunoreactivity. Gel chromatography of the GH-like immunoreactivity (Sephadex G-100) indicated the presence of several GH-like fragments ranging in the M_r range of 7,000 to 55,000. Analyses of the PRL-like ir-material found in pineal tissue on HPLC using a TSK 545-DEAE column led to the resolution into a single peak of immunoreactivity. A single peak of activity was also observed following chromatofocusing and hydrophobic interaction chromatography of the ir-peak from the TSK 545-DEAE column. The PRL-like ir-material inhibited the binding of [¹²⁵I]ovine PRL-S14 to anti-ovine PRL antibodies without showing an affinity for binding to anti-rat PRL or anti-bovine GH antibodies. Scatchard analysis of the binding of pineal PRL-like ir-material and pituitary ovine PRL-S14 to liver membranes from day-20 pregnant rats revealed similar affinity constants (K_a of 4.7 ± 0.2 × 10⁹ M^-1). In addition, the replication of Nb 2 Node rat lymphoma cells was stimulated by pineal PRL-like ir-material, an effect known to be specific for lactogenic hormones. The pineal PRL-like immunoreactivity appeared on sodium dodecyl sulfate polyacrylamide gels as a single major band of M_r 24,000. The functional status of PRL-and GH-like ir-material in the ovine pineal remains to be determined, but evidence is presented that the overall protein synthesis rate of the rat pineal responded to circulating concentrations of PRL.     

Microbiology of human immunodeficiency virus anorectal disease

PURPOSE: Individuals who are seropositive for the human immunodeficiency virus are at high risk for opportunistic infection and anorectal disorders. Little prospective information is available regarding anorectal pathogens in these patients. METHODS: One hundred sixty-three HIV-seropositive patients presented to the colorectal clinic between 1989 and 1992. Forty-seven (29 percent) patients were thought to have an infectious process and were prospectively studied using a standardized multiculture protocol. RESULTS: Mean age was 33 (range, 19–59) years. All were male; high-risk behavior accounted for 87 percent of HIV transmissions. Presenting complaints included anorectal pain (79 percent), pus per anum (28 percent), and blood per anum (26 percent). Examination revealed perianal tenderness (60 percent), condyloma (38 percent), perianal ulcers (38 percent), and anal fissures (34 percent). Sixty-six sets of cultures were performed; 28 patients had one set, 15 had two sets, and 4 had three sets. Thirty-two of these 47 patients (68 percent) had positive cultures including herpes (50 percent), cytomegalovirus (25 percent),Neisseria gonorrhoeae (16 percent), chlamydia (16 percent), acidfast bacilli (2 percent), and others (9 percent). Six of 32 patients with positive cultures had more than one organism cultured. Sixteen (50 percent) patients with positive cultures were treated medically, 8 (25 percent) were treated surgically and 8 (25 percent) were treated with both modalities. Sixty-one procedures were performed on 17 patients for condylomata. Eighteen patients had 20 procedures for abscesses, 50 percent of whom had positive cultures for other than common bowel flora; all improved. Fourteen patients underwent 33 procedures for perianal fistulas.Mycobacterium fortuitum was cultured from one patient who required 13 procedures for abscesses and fistulas. Forty-five (96 percent) patients were followed for an average of 12.5 months ±2.9 SEM (range, 1–94 months). Symptoms were improved or resolved in 22 of 32 (69 percent) patients with positive cultures and in 11 of 13 (84 percent) with negative cultures. CONCLUSIONS: Specific pathogens may often be identified in human immunodeficiency virus-seropositive patients with anorectal disorders if aggressively sought. Although patients without specific pathogens identified may be expected to improve with planned empiric treatment, positive identification allows more directed therapy.