芬苯哒唑长效控释丸在山羊体内的药物动力学研究

本试验用反相高效液相法测定芬苯哒唑长效控释丸在山羊体内的药物动力学。在血浆中测到芬苯哒唑代谢产物亚砜和砜，其平均浓度分别为７．１７±１．５４ｍｇ／ｍｌ和３．８６±１．０３ｎｇ／ｍｌ，但未测出原药浓度。在瘤胃液中测出的芬苯哒唑平均浓度为２１９．００±１３０．８３ｎｇ／ｍｌ。结果表明芬苯哒唑长效控释九可以在山羊体内恒定释放药物１１０天以上。     

家兔交配前后及妊娠期生殖内分泌变化的研究

选择新西兰母兔１０只，于交配前后及妊娠不同时期采血，测定ＬＨ、雌二醇（Ｅ２）、孕酮（Ｐ）浓度。结果显示：ＬＨ水平在交配前４小时为１８．０２±３．０５ｎｇ／ｍｌ，交配后４小时达４３．１４±８．７５ｎｇ／ｍｌ，交配后８小时达高峰水平１６５．１２±２６．４３ｎｇ／ｍｌ，是交配前９倍，其后逐渐降至交配前水平。Ｅ２浓度在交配前５天时为４２．５±１０．１ｐｇ／ｍｌ，交配前４小时为６８．７±１２．１ｐｇ／ｍｌ，交配后４小时为１１３．１±１３．７ｐｇ／ｍｌ，交配后８小时为１１８．５±１５．４ｐｇ／ｍｌ，其后渐降。孕酮浓度在受孕后逐步升高，交配前４小时至交配后２天，孕酮水平在１．０ｎｇ／ｍｌ左右，交配后第２天时，Ｐ水平为１．１２±０．５３ｎｇ／ｍｌ，而在交配后第３～８天时，Ｐ水平达３．８２±０．７２～１０．１０±２．３４ｎｇ／ｍｌ，是交配前后的３～１０倍，交配后第２１天，Ｐ水平为１８．９４±３．９８ｎｇ／ｍｌ，交配后２９天为４．０２±１．０５ｎｇ／ｍｌ。因此，家兔通过交配刺激排卵，也伴有ＬＨ峰值。交配３天后，Ｐ水平大幅度提高，表明家兔妊娠也需要高水平孕酮，同时也为通过测定Ｐ水平进行家兔早期妊娠诊断提供理论基础     

丙硫苯咪唑对犬贾第鞭毛虫病的疗效

通过３组实验评定丙硫苯咪唑对犬贾第鞭毛虫病的疗效。实验１给犬一次口服丙硫苯咪唑２５ｍｇ／ｋｇ，７只犬有５只的粪便贾第鞭毛虫孢囊被清除（硫酸锌浓度方法确定）。未治疗的７只犬有３只粪便孢囊被清除。实验２给犬口服丙硫苯咪唑２５ｍｇ／ｋｇ，隔１２小时一次，共４次。５只犬的粪便孢囊全被清除，未治疗的５只对照犬，一只犬的粪便孢囊被清除。实验３给犬口服丙硫苯咪唑２５ｍｇ／ｋｇ，隔１２小时一次，共４次，２０只犬中     

预防羊丙硫苯咪唑中毒

丙硫苯咪唑是高效、低毒抗蠕虫药。丙硫苯咪唑羊口服剂量１００ｍｇ／ｋｇ。我场某个体养羊户１９９８年４月份购进７０只小尾寒羊，用丙硫苯咪唑（哈尔滨生物制品二厂生产，每片含量８０ｍｇ）驱虫，用药剂量为４０ｋｇ以上大羊灌服５０片，３０ｋｇ左右中羊灌服２５片，...     

牦牛、半血野牦牛生长发育期若干激素变化规律

采用放射免疫技术对１～２４月龄家牦牛、半血野牦牛血液中ＩＮＳ，ＧＨ，ＬＨ，Ｔ，Ｐ，１７β－Ｅ＿２含量进行研究。结果表明，家牦牛、半血野牦牛ＩＮＳ均值分别为３．０８２７±１．９５５１μＵ／ｍｌ，３．１４２４±１．４６６８μＵ／ｍｌ；ＧＨ分别为３．５５４９±０．４６２４ｎｇ／ｍｌ，３．９０４８±０．６０４７ｎｇ／ｍｌ；ＬＨ分别为０．３８２２±０．００２１ｎｇ／ｍｌ，０．４０８６±０．０６４９ｎｇ／ｍｌ；Ｔ分别为５．５６２１±２．５９２７ｎｇ／ｍｌ，１１．０４３７±１０．９５０８ｎｇ／ｍｌ；Ｐ＿４分别为０．５７２９±０．５０３６ｎｇ／ｍｌ，０．３５３９±０．２０３３ｎｇ／ｍｌ；１７β－Ｅ＿２分别为２６．３５３８±１５．６４６４ｐｇ／ｍｌ，２２．７０２１±６．９４７２ｐｇ／ｍｌ。经二因子无重复观察值的方差分析表明，家牦牛和半血野牦牛之间，各月龄之间ＩＮＳ，ＧＨ，ＬＨ，Ｔ，Ｐ＿４，１７β－Ｅ＿２含量均无显著差异。     

青海毛肉兼用半细毛羊妊娠期外周血液中孕酮和雌二醇含量的测定

用放射免疫法测定了５只青海毛肉兼用半细毛羊妊娠期外周血液中孕酮和１７β－雌二醇的含量。孕酮含量随怀孕时间的增长而升高，怀孕１３０ｄ左右升到最高（８．５ｎｇ／ｍｌ±１．５３ｎｇ／ｍｌ），到分娩前１￣３ｄ降至３．３１ｎｇ／ｍｌ±１．３２ｎｇ／ｍｌ。雌二醇含量在整个怀孕期间保持较低的水平（８．３５￣１０．３２ｐｇ／ｍｌ），到分娩前１￣３ｄ升至２３．９８ｐｇ／ｍｌ±１．３２ｐｇ／ｍｌ。     

半胱胺对奶牛产奶量及血浆生长抑素、生长激素水平的影响

选用１０ 头处于泌乳中期的荷斯坦牛进行自身对照试验。对照期饲喂基础日粮,试验期在基础日粮中添加半胱胺。每隔５ 天一次,剂量为１００ｍｇ／ｋｇ 体重,共喂３ 次。结果表明,试验期奶牛日产奶量比对照期提高７ ．６ ％ （ 对照期１４ ．５ ±３ ．９ｋｇ／ 头,试验期１５ ．６ ±４ ．３ｋｇ／ 头Ｐ＜ ０ ．０５） ;奶牛采食量无明显变化,试验期饲料转化率比对照期明显提高（ 对照期０ ．３２ ±０ ．０１ ,试验期０ ．３０ ±０ ．０２ ,Ｐ＜ ０ ．０１） ;与对照期相比,试验期奶牛血浆生长抑素（ＳＳ） 水平明显下降（ 对照期１ ．２１ ±０ ．３４ｎｇ／ｍｌ,试验期０ ．１４ ±０ ．０５ｎｇ／ｍｌ,Ｐ（ ＜ ０ ．０１） ,生长激素含量显著提高（ 对照期１ ．３３ ±０ ．２６ｎｇ／ｍｌ,试验期１ ．７７ ±０ ．２９ｎｇ／ｍｌ,Ｐ＜ ０ ．０５） ;半胱胺对牛乳脂率无明显影响（ 对照期２ ．１６ ±０ ．５８ ,试验期２ ．５３ ±０ ．０６） 。以上结果表明,半胱胺能明显提高奶牛产奶量,而抑制体内生长抑素,提高内源性生长激素水平,可能为其主要的作用机制。     

丙硫苯咪唑对犬贾第鞭毛虫病的疗效

通过３组实验评定丙硫苯咪唑对犬贾第鞭毛虫病的疗效．实验１给犬一次口服丙硫苯咪唑２５ｍｇ／ｋｇ，７只犬有５只的粪便贾第鞭毛虫孢囊被清除（硫酸锌浓度方法确定）。未治疗的７只犬有３只粪便孢囊被清除。实验２给犬口服丙硫苯咪唑２５ｍｇ／ｋｇ，隔１２小时一次，共４次。５只大的粪便孢囊全被清除，未治疗的５只对照大，一只犬的粪便孢囊被清除。实验３给大口服丙硫苯咪唑２５ｍｇ／ｋｇ，隔１２小时一次，共４次，２０只犬中的１８只犬，粪便孢囊被清除。２０只对照犬的粪便孢囊全未清除。未见任何一只大有中毒征候。这些结果证明，治疗犬贾第鞭毛虫病，一次口服２５ｍｇ／ｋｇ丙硫苯咪唑无效，但一次口服２５ｍｇ／ｋｇ，隔１２小时一次，共４次。有高效而且无毒。     

丙硫苯咪唑瘤胃控释剂绵羊春季驱虫试验

绵羊１５０只，分三组进行春季驱虫试验，试验组羊投放丙硫苯咪唑瘤胃控释剂１牧／只，阳性药物对照组羊一次口服丙硫苯咪唑１０ｍｇ／ｋｇ体重，空白对照组不给任何驱虫药物，分别于投药前和投药后１５、３０、４５、６６、８６、１２０和１４０天进行粪便虫卵计数，称取体重和剪毛。结果表明，试验组在给药后８６天时，虫卵减少率为９３．７％，驱净率为８８％；阳性药物对照组在给药后４５天时，虫卵减少率已降至７７．４％，驱净     

二甲苯胺噻唑对绵羊血液及脑脊液中乙酰胆碱的影响

用荧光分光光度计的方法研究了二甲苯胺噻唑（静松灵）对乙酰胆碱（ＡＣＨ）的影响，肌注２．５ｍｇ／ｋｇ该药后，血液及脑脊液中ＡＣＨ浓度呈上升趋势，于２．５小时达峰值，血液ＡＣＨ由０时７．９６５±０．４１８ｎｇ／ｍｌ２．５小时的４３．９３９±１．３０７ｎｇ／ｍｌ（ｎ＝５，Ｐ＜０．０１），ＡＣＨ浓度增加了４．５倍，脑脊液ＡＣＨ则由０时的１２．７２２±１．３４７ｎｇ／ｍｌ增７１、９５４±２．２５７ｎｇ／ｍｌ     

药物缓慢释放剂和控制释放系统研究和应用概况（一）

本文对药物缓慢释放和控制释放系统的研究和应用概况进行综述,对其优缺点进行了探讨,并地发展前景作了展望。     

LOW RELEASE OF SELENIUM FROM RECOVERED RUMINAL PELLETS

The effectiveness of selenium pellets in grazing Merino sheep was examined by comparing the selenium status of treated and untreated animals over a 13 month period. The selenium status of treated sheep, as measured by blood glutathione peroxidase levels, had reached a maximum 3 months after treatment and there was a marked decline between 5 and 13 months. All pellets were recovered from treated sheep at slaughter this confirmed that the observed decline was not due to a loss of pellets.
In a separate study sheep were slaughtered 14 months after treatment and some of the recovered pellets were readministered to sheep maintained on a low selenium diet. The selenium status of the sheep receiving recovered pellets remained low. This bioassay technique indicated that there was little available selenium released from these pellets. The selenium status of sheep given previously unused pellets was declining after 18 weeks.     

埃维菌素长效控释丸在绵羊体内的药物动力学研究

用反相高效液相色谱法测定埃维菌素长效控制释放丸在血浆和胃液中的药物动力学，所测成分为埃维菌素Ｂ１ａ。流动相为乙腈：甲醇：水＝７２：１８：１０，紫外检测波长为２４５ｕｍ，流速１ｍｌ／ｍｉｎ。结果表明埃维菌素长效控释丸在绵羊体内稳定释放，可持续１１０天以上，血浆和胃液中埃维菌素Ｂ１ａ的浓度分别为８．３７±１．９０ｎｇ／ｍｌ和４１．２４±２３．４１ｎｇ／ｍｌ。     

克伦特罗缓释药囊的制备,体外释药及对育肥猪生产性能的影响

选用可生物降的白氨酸，谷氨酸甲酯，谷氨酸三元聚物制成克伦特罗缓释药囊。体外释药研究所表明，药囊能保持长期缓慢恒速释药，释药速率随取合物中谷氨酸含量增多而增大，其中ＰＬＭＧＧ－２５的克伦特罗药囊释药时间为８０ｄ、稳态后每天释药量平均为１．２３ｍｇ／ｄ。     

控制包虫病的缓释剂型研究─抗包虫病犬用吡喹酮缓释包埋剂(PSRI)现场防治细粒棘球绦虫试验

研制了三种抗包虫病大用吡喹酮缓释包埋剂，通过人工感染试验表明：吡喹酮缓释包埋剂3号给犬皮下植入7个月时，进行原头蚴人工感染，对细粒棘球绦虫的预防保护率达98．46％；包埋剂内还剩余吡喹酮48．93％，至1年左右药物才被吸收完毕，预防期可能长达一年，故优选了本缓释剂。本文报道应用吡喹酮缓释包埋剂3号在包虫病高发区甘肃省天祝藏族自治县进行的现场试验，经113只犬的植入试验，在植入8个月和14个月时用氢溴酸槟榔碱泻下法抽检38只植入犬，皆未发现细粒棘球绦虫的感染，预防保护率为100％，而对照犬的感染率为20％，预防保护效果极显著，从而肯定了抗包虫病犬用吡喹酮缓释包埋剂预防犬感染细粒棘球绦虫的良好效果。     

犬应用吡喹酮缓释剂后血药浓度的检测

应用反相高效液相色谱法测定犬用吡喹酮缓释剂后的血药浓度。犬应用包埋缓释剂后1～7个月血药浓度为0．48～1．45μg／ml；犬应用注射缓释剂后1～6个月血药浓度为0．051～0．2μg／ml；犬口服常用驱（杀）虫剂量后1～8小时的血药浓度为0．66～1．60μg／ml。显然前者与口服浓度相当，而后者则远远低于口服浓度；前者预防效果减虫率达98．46～100％，后者仅达55．65～65．11％；从而以确凿的数据证实犬用包埋型缓释剂的有效预防期至少在7个月以上。     

SLOW RELEASE CISPLATIN COMBINED WITH RADIATION FOR THE TREATMENT OF CANINE NASAL TUMORS

Thirteen dogs with malignant tumors of the nasal cavity were treated with a combination of slow release cisplatin and megavoltage radiation. Radiation was delivered on a Monday through Friday schedule using a 6 MV linear accelerator. The median total dose was 49.5 Gy (range 49.5-56 Gy). Cisplatin was given using an open-cell polylactic acid polymer, impregnated with the drug and implanted intramus-cularly at a distant site, as a slow release delivery system (OPLAn-Pt [THM Biomedical, Inc]). The median dose used was 60 mg/m2 (range 60–100 mg/m2). When combined with radiation, this delivery system caused no systemic drug toxicity, and a local tissue reaction was seen in only two dogs. Acute side effects to normal tissue from radiation were not enhanced, as measured by subjective assessment. When compared to a group of historical controls that received radiation without OPLA-Pt, the dogs that received combined radiation and cisplatin had longer overall survival times, with a median of 580 days. The control group had a median survival of 325 days. Previously reported median survival times for comparable megavoltage radiation treatment range from 6 to 13 months. Some dogs in both groups also received adjubant chemotherapy but this did not influence survival time. By multivariate analysis, only the use of OPLA-Pt was found to significantly influence survival, with a p value of p = 0.023. Mega-voltage radiation and slow release cisplatin appears to be a well tolerated combination that may favorably affect survival of dogs with nasal tumors.     

EVALUATION OF THE POTENTIAL OF SYSTEMIC SLOW RELEASE CHEMICAL TREATMENTS FOR CONTROL OF THE CATTLE TICK (BOOPHILUS MICROPLUS) USING IVERMECTIN

SUMMARY Stall and field trials with cattle infested with various acaricide-resistant strains of cattle tick, have demonstrated the potential of ivermectin as a systemic tickicide. A dosage of 200 μg/kg, administered subcutaneously to animals naturally infested in the field, gave satisfactory tick control for 21 days, after an initial lag period of 2 days immediately following treatment, during which significant numbers of ticks survived. Daily subcutaneous treatments, administered so as to simulate slow release, indicated that a dosage of 15 μg/skg/day should give complete tick control if the chemical could be released continuously from a subcutaneous implant. The potency of ivermectin, assessed by in vitro tests against engorged adults, suggests that the tickicidal activity could be associated with the parent compound per se rather than a metabolite.