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981.
SUMMARY Imidocarb diproprionate (IMDP) was used therapeutically at a dose of 1.2 mg IMDP/kg of body weight against Theileria sergenti infections in Hereford heifers on the island of Jeju-Do, Republic of Korea. In the first experiment IMDP was seen to be at least as effective in reducing T. sergenti parasitaemias as primaquine phosphate (primaquine), the drug normally used on the island. In the second and third experiments IMDP was shown to reduce T. sergenti parasitaemias by about 80%. No drug is known to be completely effective against T. sergenti infections but the suggestion is made that IMDP may be used in preference to primaquine for treatment of acutely ill animals since it also has the advantage of eliminating Babesia ovata, another element of the piroplasmosis syndrome on the island.  相似文献   
982.
香石竹叶斑病防治研究   总被引:1,自引:0,他引:1  
本文报道作者等于1978~1980年间对香石竹叶斑病的防治研究结果。此病主要为害叶片造成叶斑和叶枯,但也可造成茎腐和花枯。根据本病原分生孢子色泽较深、喙较短、纵向斜向分隔较多等特点,确认上海地区香石竹叶斑病病原为Alternaria dianthi Stev.et Hall而非Alternaria dianthicola Neerganrd。对其形态大小进行了描述。土中病残体是此病的初次侵染源。越冬后的分生孢子是此病的初侵染源菌态之一。霉季和台风季多雨.露地栽培、种植感病品系均有利于发病。栽培措施可以减轻发病程度。试验证明防病有效的药剂有:土壤消毒可以0.1%五氯硝基苯拌土;插条浸药:10%401的1000倍液浸半小时或0.1%高锰酸钾液浸10分钟;生长季节喷雾:0.5%的波尔多液或75%的代森锰锌500倍液,10天1次,在每次摘芽作业后及时喷施。  相似文献   
983.
Antitumor principle constituents of Myrica rubra Var. acuminata   总被引:2,自引:0,他引:2  
Myrica rubra var. acuminata is a native shrub widely distributed and used as folk medicine in Taiwan for stomach disorders and diarrhea. Column chromatography combined with cytotoxic bioassay-guided fractionation was performed to isolate the antitumor principles from fresh leaves of M. rubravar. acuminata. The 20% MeOH eluate fraction of M. rubra var. acuminata inhibited the viability of HeLa and P-388 cells in an in vitro assay and an in vivo P-388 tumor-bearing CDF(1) mouse model. The percent increase in life span (%ILS) of 20% MeOH eluate fraction was greater than 125%. (-)-Epigallocatechin 3-O-gallate (1) and prodelphinidin A-2,3'-O-gallate (2) were isolated from D-20 as the antitumor principle components. Both compounds can inhibit the growth of HeLa cells, but 1 had lower cytotoxic effects in normal cervical fibroblasts than did 2. Moreover, pretreatment with a caspase-3 specific inhibitor prevented 1- and 2-induced poly(ADP-ribose) polymerase cleavage. In view of these results, we suggest that 1 and 2 can induce apoptosis in HeLa cells and that activation of caspase-3 may provide a mechanistic explanation for their cytotoxic effects. Therefore, we suggest that the 20% MeOH eluate fraction extract is good for health and that M. rubra var. acuminata is an economically valuable plant.  相似文献   
984.
The effects of ethylene glycol monoethyl ether (EGEE) on testicular cell populations in rats were investigated by a flow cytometric method. Rats were administered by gavage with EGEE at the various doses of 0 (saline alone), 100, 200, 400, and 800 mg/kg body weight/day for 4 weeks. The treatment of EGEE caused decreases in the weight of testis and epididymis and in the number of testicular cells. Histopathologically, exfoliation of germ cells into the tubular lumen was observed at the doses of above 200 mg/kg. The treatment of EGEE at the dose of 400 mg/kg caused moderate testicular degeneration. A significant depletion of haploid cells and a disproportionate ratio of diploid and tetraploid cells were observed as determined by flow cytometric analysis. These results indicate that the toxic effect of EGEE on the male reproductive system may be strongly associated with the disproportion of testicular germ cells.  相似文献   
985.
Some studies have shown that relative to baseline, the renal resistive index (RI) remains unchanged in nonobstructed kidneys and increases in obstructed kidneys after administration of furosemide. To our knowledge, the effect of mannitol administration on the renal RI of dogs has not been reported. We evaluated the renal RI in 16 kidneys in 8 young adult dogs after administration of mannitol. The mean RI decreased significantly from baseline (P < .01). Additionally, left complete ureteral obstruction wasinduced in 5 dogs. Evaluation by Doppler ultrasonography was performed for 5 days. On the 5th day, Doppler examination was repeated at 30 and 60 minutes after administration of mannitol to obstructed dogs. After induction of left ureteral obstruction, the RI of the left kidney increased significantly over 5 consecutive days. Administration of mannitol decreased the RI in the nonobstructed contralateral kidneys, and thus the RI difference between obstructed and nonobstructed kidneys was increased above normal (P < .001). In conclusion, administration of mannitol may be useful as another diuretic agent to identify unilateral ureteral obstruction on Doppler sonographic examination.  相似文献   
986.
Ma M  Guan G  Lu B  Liu A  Liu Z  Chang Z  Li F  Chang F  Luo J  Lu W  Zhang Q  Yuan G  Yin H  Boulard C 《Veterinary parasitology》2003,117(1-2):147-151
A chemotherapy trial was conducted to determine the lowest dosage of injectable preparation of ivermectin against Hypoderma spp. infestation in yaks in Tibetan areas in Tianzhu county, Gansu province, in northwest of China. One hundred and sixty yaks were randomly divided into four groups of 40 yaks for the trial. The first three groups were treated by subcutaneous injection in the neck with 0.1% ivermectin (respectively, 1, 5, 10 microg/kg body weight). The fourth group was not treated and considered as control group. All the experiments were performed in November 2000 and the animals were examined for the presence of warbles in the next March and May. The results indicated that there was no warbles found on the back of treated animal while third stage larvae were palpated on back of some of the yaks in control group. It is concluded that dosage of 1 microg/kg ivermectin injectable was sufficient to kill or stop development of larvae of Hypoderma spp. in naturally infected yaks if administrated in November.  相似文献   
987.
In this immunocytochemical study on the constitutive expression of Pax-7 protein in the postnatal chicken brain, Pax-7 showed region and cell type specific expression. In the optic tectum, only cells in grey matter showed positive immunoreactivities (IRs), whereas those in the white matters did not show any IRs. In thalamic nuclei and several pontine nuclei, we also localized Pax-7 positive IRs. On the contrary, in the cerebellum, Pax-7 was mainly localized within the Bergmann glia, whereas Purkinje cells did not show any IRs. In double immunolabelling studies, most of the Pax-7 IRs did not originate from neuroglial cells such as oligodendrocytes, microglia or astrocytes, but from neurons, with the exception of Bergmann glia in the cerebellum. The presence of Pax-7 IRs in the adult chicken brain could suggest that Pax-7 might play a role in maintaining normal physiological function in some postnatal chicken brain cells.  相似文献   
988.
The purpose of the present study was to examine the antigenicity of turkey coronavirus (TCV) isolates from various geographic areas with antibodies to different viruses. Seventeen isolates of TCV were recovered from intestinal samples submitted to Animal Disease Diagnostic Laboratory, Purdue University, from turkey farms located in different geographic areas. The prototype TCV Minnesota isolate (TCV-ATCC) was obtained from the American Type Culture Collection. Intestinal sections were prepared from turkey embryos infected with different TCV isolates and reacted with polyclonal or monoclonal antibodies to TCV, infectious bronchitis virus (IBV), bovine coronavirus (BCV), transmissible gastroenteritis virus (TGEV), reovirus, rotavirus, adenovirus, or enterovirus in immunofluorescent antibody staining. All 18 TCV isolates have the same antigenic reactivity pattern with the same panel of antibodies. Positive reactivity was seen with polyclonal antibodies to the TCV Indiana isolate, the TCV Virginia isolate, TCV-ATCC, and the IBV Massachusetts strain as well as monoclonal antibodies to the TCV North Carolina isolate or the membrane protein of IBV. Antibodies to BCV or TGEV were not reactive with any of the TCV isolates. Reactivity of antibodies to unrelated virus, rotavirus, reovirus, adenovirus, or enterovirus with different TCV isolates was all negative, except positive response was seen between enterovirus antibody and a TCV western North Carolina isolate, suggesting coinfection of turkeys with TCV and enterovirus in that particular case. The results indicated that the TCV isolates from these geographic locations in the U.S. shared close antigenicity and were antigenically related to IBV.  相似文献   
989.
The objective of the present study was to evaluate the protective effect of humoral and cellular immunities on turkeys infected with turkey coronavirus (TCV). Two trials were conducted with two separate hatches of turkey poults. Turkey's were experimentally immunosuppressed with cyclosporin A (CsA) or cyclophosphamide (CY) and infected with TCV. Prior to infection, treatment with CsA selectively suppressed T cell activity as revealed by 2-3 fold decreased (p < 0.1) lymphocyte proliferation responses to a T cell mitogen, concanavalin A (Con A). Treatment with CY mainly induced B cell deficiency as indicated by significant reductions (p < 0.05) in antibody responses to sheep erythrocytes 7 days after injection. Body weight gain of turkeys treated with CY was significantly lower (p < 0.05) than that of untreated turkeys at 9 days post-infection (PI). Turkeys treated with CY had 1-2 fold higher immunofluorescent antibody assay (IFA) scores for TCV antigens (p < 0.05) in the intestine than untreated turkeys at 9 or 14 days PI. These results suggested that humoral immunity against TCV infection may be important in turkeys.  相似文献   
990.
In the genome of strains of very virulent Marek's disease virus serotype 1(vvMDV1), such as Md5 and RB1B, the meq open reading frame (ORF) encoding a 339-amino-acid bZIP protein, is present, while a slightly longer meq ORF, termed as L-meq, in which a 180-bp sequence is inserted into the meq ORF is found in other strains of MDV1, such as CV1988/R6 and attenuated JM. When chickens were infected with vvMDV1 strains and the meq gene was amplified by nested polymerase chain reaction (PCR), the meq gene was detected throughout the experimental period for 7 weeks post inoculation (pi). However, the L-meq gene was also detected at 3 to 5 weeks and 3 to 4 weeks pi. in Md5-infected and RB1B-infected chickens, respectively. In the case of chickens infected with an attenuated MDV1, the JM strain, the L-meq gene was detected at 2 to 7 weeks pi., and the meq gene was also detected at 2 to 6 weeks pi. Both L-meq and meq genes were detected in chickens infected with an attenuated nononcogenic vaccine strain of MDV1 (CVI988/R6), throughout the experimental period. Though quantitative PCR was not performed, a larger amount of the PCR products corresponding to the L-meq than the meq gene was amplified from chickens infected with JM or CVI988/R6. These results suggest that a dynamic population shift between the MDV subpopulations displaying meq and L-meq genes occurs in chickens during the course of MDV infection. Since the MDV subpopulation that displays the L-meq gene only displays it during the latent phase, the L-meq and its gene product, if any, might contribute to the maintenance of the MDV latency.  相似文献   
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