硼镁石粉有效灭螺成分的探讨

目的阐明硼镁石粉灭螺作用的有效成分.方法矿石样品经HNO3及HNO3-HClO4方法消解后,采用石墨炉原子吸收法测其砷、铅、镉等元素的含量;采用WHO"杀螺剂实验室终筛方法"中的浸泡法进行灭螺试验.结果硼镁石粉(灭螺灵1号)及西藏改则的硼镁矿石中砷含量分别达34.10μg/g及61.70μg/g,远高于其他硼镁矿石,灭螺实验显示砷及硼化合物均具有灭螺作用.结论西藏硼镁石粉中的砷含量偏高,其杀灭钉螺的有效成分可能是砷及硼化合物.     

硼镁石粉杀灭钉螺效果和急性鱼毒的评价

目的评价硼镁石粉杀灭钉螺效果和现场推广应用前景,了解其对鱼类的急性毒性.方法 采用撒粉法进行实验室和不同类型现场杀螺试验,用斑马鱼进行急性鱼毒试验.结果硼镁石粉在实验室撒粉施药后3、7、15 d的LC5.分别为228.19、34.89、12.47 g/m2,显示该药具有明确的量-效和时-效关系.江滩地区200 g/m2的杀螺效果较好,180 d钉螺校正死亡率和活螺密度下降率均达100.0%;山丘地区200 g/m2 210 d活螺密度下降96.1%;沿海高沙土地区灭螺效果较差,80 g/m2几乎无杀螺效果,200 g/m2钉螺死亡率也很低.现场观察发现硼镁石粉对植物有毒害作用,并随剂量增加而毒害加重;同时,施用硼镁石粉后土壤碱性明显增加,且随剂量增加而碱性增加.急性鱼毒显示48、72、96 h LC50分别为964.32、633.66、523.74 mg/L.结论硼镁石粉现场杀螺作用缓慢,用量大,对鱼类安全,对植物及土壤有损害.硼镁石粉中有杀螺作用的成分亟待研究阐明.     

硼镁石粉灭螺评价

硼镁石粉是我国科学工作者筛选出的一种具有明显灭螺效果的矿物质,应用于现场灭螺已有十多年的历史.研究表明,在室内及现场应用硼镁石粉均有肯定的灭螺效果,作用持久,效果稳定[1].此外,硼镁石粉用于灭螺还具有成本低,使用方便,采用人工或机械撒粉均可,可用于山丘型和较为复杂的有螺环境,对皮肤和黏膜无刺激,对鱼、蚌无明显毒性等特点[1,2].     

烟氯复合物和硼镁石粉现场灭螺试验

目的　通过扩大现场试验 ,掌握烟氯复合物和硼镁石粉的现场灭螺效果。方法　采用浸杀法、喷洒法和撒粉法进行现场灭螺试验。结果　采用烟氯复合物 0 .8m g/ L 和氯硝柳胺 2 m g/ L 平行比较灭螺 ,浸杀法 30 d的钉螺校正死亡率分别为 91.5 7%和 92 .38% ;喷洒法 30 d的钉螺校正死亡率分别为 90 .0 2 %和 90 .5 6 %。采用硼镁石粉 80 g/ m2撒粉 ,雨天和晴天撒粉 ,30 d的钉螺校正死亡率分别为 76 .10 %和 93.0 0 %。结论　采用烟氯复合物 0 .8m g/ L 以及氯硝柳胺 2 mg/ L 进行浸杀和喷洒灭螺 ,其灭螺效果基本一致 ,但烟氯复合物灭螺的用量比氯硝柳胺减少了 6 0 .0 0 %。硼镁石粉具有杀灭钉螺的作用。晴天撒粉比雨天撒粉灭螺效果要好 ,半年后灭螺效果开始下降     

硼镁石粉现场灭螺效果观察

目的：应用硼镁石粉在河道、菜地、鱼池和有温泉水流动的沟渠进行灭螺，观察灭螺效果。方法：使用硼镁石粉对内陆9个有螺环境进行灭螺，其中6个未预处理，3个先割去杂草，冬季撒粉，剂量200g/m^2,6个月和1年观察灭螺效果，结果：9个环境中经1次硼镁石粉灭螺后，7个环境未查到活螺，2个环境钉螺死亡率分别为93．0％（198／213）和88．5％（69／78），对这2个环境复灭1次，灭后1年，查到的钉螺均为死螺，灭螺时未发生鱼，蚌死亡，结论：硼镁石粉对钉螺有较好的杀灭作用，具有价廉，低毒，使用方便等优点，可在鱼池，山区，河道等内陆地区使用。     

硼镁石粉杀灭钉螺的实验研究

目的 验证硼镁石粉的杀螺效果，分析其作用机理，为其合理使用提供依据。方法采用纸钱法、熏杀法以及WHO“杀螺剂实验室终筛法”中的浸杀法和接触法测试和比较硼镁石粉的灭螺效果。结果 硼镁石粉熏杀法没有灭螺效果，接触法和浸杀法的效果较好。浸杀法起效时间短，接触法效果较稳定。27℃作用时问4d时，接触法的LD50为4．07g／m^2，作用时问越长效果越好。结论 硼镁石粉用于灭螺时是逐渐起效的，灭螺效果好，长期效果稳定，其作用机理可能是通过接触可溶物而杀灭钉螺。     

硼镁石粉氯烟复合物在山丘地区的灭螺效果

目的 了解硼镁石粉、氯烟复合物在山丘地区的灭螺效果。方法 采用硼镁石粉80g／m^2干撒，氯烟复合物0．8g／m^2喷洒，同时与氯硝柳胺2g／m^2喷洒和空白对照作对比。结果 硼镁石粉撒药后7d，其灭螺效果不如氯硝柳胺，但l5d及30d后其活螺密度即与氯硝柳胺差异无显著性，钉螺死亡率在30d显著高于氯硝柳胺，活螺密度持续下降。氯烟复合物灭螺效果不明显。结论 硼镁石粉灭螺效果较好，随着时间延长，其灭螺效果逐渐上升。     

硼镁石粉氯烟复合物在湖区的杀螺效果

目的探索硼镁石粉、氯烟复合物在湖区现场的杀螺效果。方法采用硼镁石粉80g/m2与氯烟复合物0.8g/m2喷洒,氯烟复合物0.8mg/L浸杀,同时以50%氯硝柳胺乙醇胺盐可湿性粉剂和清水作空白对照。结果硼镁石粉、氯烟复合物10月份杀螺效果不如氯硝柳胺。5月份3种杀螺药物的杀螺效果相近,经检验,差异无显著性(P>0.05)。结论硼镁石粉、氯烟复合物杀螺效果及稳定性受季节及环境影响因素较氯硝柳胺乙醇胺盐大。春季灭螺使用硼镁石粉喷洒和氯烟复合物浸杀效果好。     

硼镁石粉灭螺研究

目的观察硼镁石粉室内灭螺效果和现场应用效果。方法室内试验和现场试验 ,参照徐国余方法 [1 ] ,现场试验面积每块 1 5 m2 。现场应用 ,冬春季用手撒硼镁石粉 80 g/ m2 ;重点环境灭螺 ,1 60 g/ m2 ～ 2 5 0 g/ m2 。结果室内试验 ,40 g/ m2 ,2 5℃ ,7d后钉螺死亡率 95 .0 %。现场试验 ,80 g/ m2 ,3 0 d,钉螺死亡率 90 .9%。现场应用 :江浦县江滩 2 0 0 0 0 0 m2 ,80 g/ m2 ,灭后 3 0 d,钉螺死亡率 90 .6%。7个区县重点环境灭螺 :江浦县内陆 5 2 5 0 0 m2 ,4个区的江滩 2 0 0 5 1 7m2 和雨花区石驳岸 3 3 3 5 0 m2 ,经一次 (个别环境 2次 )灭螺 ,灭后未查到活螺。江宁区山区1 90 0 0 0 m2 ,灭后 1年钉螺死亡率 95 .4% ,其中 3块 1 60 0 0 m2查不到活螺 ,撒粉后可见植物发黄。结论硼镁石粉灭螺有效剂量 :(1 ) 80 g/ m2 ,4～ 1 1月份撒粉。 (2 )灭光钉螺 2 0 0 g/ m2以上 ,冬春季撒粉。剂量大对植物有毒害     

硼镁石粉和灭螺灵的杀螺效果观察

据报道 [1] ,硼镁石粉对湖区钉螺具有良好的杀灭作用 ,且有持效时间长 ,使用方便 ,价廉低毒等特点。为进一步观察该药在云南血吸虫病流行区的灭螺效果 ,我们开展了硼镁石粉及其以此为基料制成的灭螺灵的灭螺试验工作。1　材料和方法1 .1　材料1 .1 .1　硼镁石粉　由南京市疾病预防控制中心提供。1 .1 .2　灭螺灵　以四聚乙醛和氨基甲酸酯类农药经混匀、复配制成原料 ,然后 ,取原料一定量 ,加水润湿并搅拌1 0 min,随即加入 4 9倍量的硼镁石粉 ,再次搅拌 1 0 min,待充分混匀后倒入搪瓷盘中 ,保持湿润 2 4 h后阴干 ,阴干后筛制成 <6 0目的粉剂…     

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.     

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.     

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.     

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.