广东雷州市家栖鼠类分布及其种群结构的调查

目的了解雷州市区鼠形动物的分布及其种群结构。方法按一定比例分层抽样,采用鼠夹法在不同环境捕鼠。结果共捕鼠339只,隶属2目2科3属4种,其种群结构为褐家鼠、黄胸鼠、臭鼩鼱和小家鼠,市区以褐家鼠和黄胸鼠为优势种群,在城乡结合部和居民区以黄胸鼠为主,城市绿化带以臭鼩鼱为主。结论雷州市区鼠类防制以黄胸鼠和褐家鼠为主要防制对象,对192只雌鼠进行妊娠斑解剖观察。     

龙门县家栖鼠的群落结构特征初探

目的 根据龙门县城区的鼠情监测结果，分析家栖鼠的群落结构特征，为开展灭鼠防病工作提供依据。方法 采用鼠茏法，晚放晨收，并对捕捉的鼠类进行鉴别和分类。结果 龙门县城区鼠类群落由褐家鼠、黄胸鼠、小家鼠和臭鼩鼱组成，鼠密度较高(12．4％)；市区、城郊地区和重点行业均以褐家鼠为优势种。结论 重点行业仍是今后鼠害防制的重点生境类型。城郊地区则应以褐家鼠为主要防制目标，城区应采取以防鼠设施为主的全面的综合防制方法进行防制。     

C型肉毒梭菌毒素灭家鼠效果观察

作者于１９９４年１１～１２月在安徽省枞阳县长沙乡，用Ｃ型肉毒梭菌毒素对黄胸鼠和褐家鼠进行实验室和现场灭鼠效果观察。用灌胃法测定对黄胸鼠最小致死剂量为６４０００ＭＵ／ｋｇ体重，对褐家鼠为３２０００ＭＵ／ｋｇ体重。０．５％Ｃ型肉毒梭菌毒素大米毒饵，初遇和再遇适口性摄食系数褐家鼠为０．８６和０．６２；黄胸鼠为０．７５和０．５４．０．５％Ｃ型肉毒梭菌毒素现场灭效，鼠笼法灭鼠率为１８．０５％，粉迹法为２５．９６％；０．００５％溴敌隆毒饵灭鼠率鼠笼法为７５．６６％，粉迹法调查为７７．９５％：两者差别非常显著（Ｐ＜０．０１）．表明Ｃ型肉毒梭菌毒素对黄胸鼠和褐家鼠毒力较小。     

闽东耕作区的鼠类生态学研究

目的：调查闽东耕作区的鼠类及其体外寄生虫。方法：笼捕活鼠，进行鼠及体外寄生虫分类鉴定。结果：鼠类隶属啮齿目鼠科９种，食虫目科２种；种群的空间配置，从边缘地带住宅到山地灌木林区依次为褐家鼠、小家鼠、黄胸鼠、臭、卡氏小鼠、黄毛鼠、黑线姬鼠、水麝、社鼠、针毛鼠和白腹巨鼠。鼠体外寄生虫有恙螨２科３亚科１２属２７种，其中水纤恙螨为一新种，高山真棒恙螨为我省新纪录；革螨３科１１属１３种；蚤２总科４科９属１１种。结论：基本摸清该地区鼠类及其体外寄生虫本底     

A compact and inexpensive drinkometer for use with small animals

A compact and low cost solid state drinkometer design is presented permitting electrical isolation of the animal from the recording system. Data correlating licks with daily water intake (ml) and temporal consumption patterns are provided for several Long Evans rats.     

CD4+ effector T cell distribution in vivo: TGF-beta 1/TGF-beta receptor II interaction during activation mediates accumulation in the target tissue by preferential proliferation

CD4(+) effector T cells generated in mesenteric lymph nodes (mLN) leave into the blood. Although they enter many tissues, mLN effector T cells are later found preferentially in the gut,the drainage area of mLN. We show in the rat that this is not an intrinsic property of mLN T cells. Instead, within the mLN milieu T cells are instructed by cytokines such as transforming growth factor beta 1 (TGF-beta 1) to up-regulate TGF-beta receptor II (TGF-beta RII) during activation. This enables effector T cells to continue proliferation upon subsequent contact with TGF-beta 1 in mLN and gut, and to accumulate in the lymph node draining area, the most likely site of pathogen invasion.     

Emetine ditartrate: a possible lead for emergency contraception

Interception of pregnancy in its initial stage is an attractive and viable approach to contraception. A chemical agent, taken within the first few days of missed menses, intercepts the conception, which is expelled with menstrual flow. The main targets of such agents are the uterus, blastocyst and the growing trophoblasts, whose nutritional requirement is inhibited. Our previous work has identified several nonsteroidal chemical entities as pregnancy interceptives in rodents and infrahuman primates. However, none reached clinical stage due to their ineffectiveness by oral route. Nevertheless, parallel to these rationally designed synthetic compounds, a program was ongoing to identify natural product(s) that can be used as interceptives. We are reporting for the first time the detailed profile of emetine ditartrate, a compound whose pregnancy interceptive efficacy has been studied in mouse, rat, hamster, guinea pig and rabbit by oral and intravaginal routes of administration. By the oral route, the compound caused 100% resorption of the fetuses in rat, hamster and guinea pig at 6.0, 5.0 and 3.0 mg/kg, respectively, on administration during peri- and early postimplantation periods of pregnancy (depending upon the day of implantation in each species). By intravaginal route, the compound was administered once in the form of a vaginal pessary on the day of implantation in respective species; interception of pregnancy was not achieved completely in rat and hamster at doses four to five times the oral dose in multi-day schedule. However, in guinea pig and rabbit it was fully effective at 7.0 and 70.0 mg/animal, respectively. The compound was devoid of estrogenic, antiestrogenic and progestational activity but possessed mild antiprogestational activity at the high dose in vivo. In in vitro assay, however, it did not show any significant binding to estrogen and progesterone receptors. The mode of action of the compound was found to be mainly on the uterus and early embryos around implantation, possibly on the trophoblasts and endometrial cells at the attachment site. The absence of 100% efficacy in rat and hamster by intravaginal route, but not by oral route, is possibly due to poor absorption of the compound through the vagina in these species. The guinea pig and rabbit, therefore, seem the better species for evaluating the efficacy of the compound administered by the vaginal route.     

Kinematics of treadmill locomotion in rats conceived, born, and reared in a hypergravity field (2 g). Adaptation to 1 g

The kinematics of treadmill locomotion in rats conceived, born, and raised in a hypergravity environment (HG: 2 g) until the age of 3 months was investigated for 5 weeks after their exposition to earth’s gravity. The locomotor performance of the HG rats (N=7) was compared to that of age-matched control rats (N=8) housed at 1 g for the same period. Kinematic analysis of treadmill locomotion was performed up to 35 days of terrestrial life by an optoelectronic motion analyzer (ELITE system). Results showed that the HG rats exhibited a faster locomotor rhythm (increased number of steps/s), walked closer to the ground, and had a more dorsiflexed foot position. Also, HG rats had shorter steps. The data also highlight a fast adaptation to normal gravity since all the locomotor parameters returned to normal values within 3 weeks. The locomotor modifications may be seen as the persistence of a hypergravity-induced posturo-locomotor adaptation in the centrifuge and/or to more functional changes of sensorimotor systems. Because locomotor performance of HG rats is not severely affected, it is concluded that early development of locomotion processes is highly resistant to gravito-inertial changes.     

Can spleen transplantation induce tolerance? A review of the literature

In some rodent strain combinations, allogeneic spleen transplantation induces tolerance spontaneously to itself and to other donor-specific organs. In other combinations, a state of tolerance has been achieved in the weakened immune system of the recipient. The data indicate that if a balance can be achieved between host-versus-graft and graft-versus-host responses, tolerance develops, possibly due to the development of suppressor/regulatory cells. There have been a number of unsuccessful studies in outbred large animals, but none in MHC-defined donor-recipient pairs, and none in which the protocol specifically aimed at inducing tolerance. Spleen transplantation has been performed in approximately 50 humans for a number of reasons, however no clear immunologic advantage has been reported. Graft-versus-host disease (GVHD) was documented in at least 3 patients, and was lethal in one case, despite excision of the donor spleen. The advantages of tolerance over chronic immunosuppressive therapy are so great that a potentially tolerogenic approach such as spleen transplantation would seem worthy of further investigation in a suitable large animal model. Such a study is ongoing at our center.     

2008-2009年中俄边境满洲里-后贝加尔口岸地区鼠类名录

本文根据中俄联合监测小组对中俄边境口岸地区鼠形动物监测调查资料,编撰2008年中俄边境满洲里-后贝加尔口岸地区鼠类名录,旨在为该地区的公共卫生工作及相关鼠传疾病的防治提供基础资料。结果满洲里口岸地区鼠形动物为2目6科8属8种,后贝加尔口岸地区鼠形动物为2目4科6属7种。