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91.
In a large pig breeding herd with high prevalence of post-parturient diseases of the sows, weaned sows of different parity groups with (n = 663) or without (n = 1125) recidiving mastitis metritis agalactia (MMA) in their previous history were subjected to ultrasonography. A total of 114 of 663 sows with recidiving MMA in their previous history and with ultrasonographic visible mammary gland changes, and 157 of sows without recidiving MMA in their previous history were culled and subjected to gross pathological and bacteriological examination of their mammary glands. The sows having suffered MMA had more (p < 0.001) hyperechogenic images in their mammary glands compared with the sow having suffered no recidiving MMA. Abdominal glands were more (p < 0.01) prone to pathological changes compared with the pectoral ones. Sows of high parity had more hyperechogenic images and gross pathological changes in their mammary glands compared with the sows of low parity.  相似文献   
92.
分析了我国目前城市公交车用的刹车片存在的诸多质量问题,并提出解决的手段,而且提供了一种高性能汽车刹车片的研究结果。  相似文献   
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蝇害已经成为危害规模化畜禽养殖的重要问题。文章回顾了防治蝇害的三代杀虫剂的发展过程和存在的问题 ;展望了作为新一代环境友好防治蝇害药物的昆虫生长调节剂的开发前景。  相似文献   
97.
从上海光明乳业股份有限公司车间发酵罐中分离出4株酸奶噬菌体。1号噬菌体头部呈六角形,平均直径为95.1nm,头部剖面平均面积为8184.8nm^2,尾部的平均直径为18.3nm,平均长度为403.4nm;2号噬菌体头部呈六角形,平均直径为85.4nm,头部剖面平均面积为8046.2nm^2,尾部的平均直径为23.3nm,平均长度为549.4nm;3号噬菌体头部呈六角形,平均直径为95.5nm,头部剖面平均面积为9792.3nm^2,尾部的平均直径为19.8nm,平均长度为450.5nm;4号噬菌体头部呈六角形,平均直径为119.3nm.头部剖面平均面积为12586.1nm^2,尾部的平均直径为23.6nm,平均长度为520.5nm。  相似文献   
98.
The data obtained in the workshop provide further evidence that CH128A and IL-A26 and the 12 new mAbs that form a cluster recognise the bovine orthologue of CD2. The mAbs inhibit rosetting with SRBC, stain cells in primary and secondary lymphoid organs in patterns consistent with those obtained in humans with anti-CD2 mAbs, and the 11 IgG mAbs all immunoprecipitate a peptide with a Mr of 58-62 kDa. It is not clear from the studies whether the epitopes defined by the mAbs correspond with the region I and II epitopes present on CD2. None of the data suggest that any of the mAbs recognise the region III (CDD2R) epitope (Peterson and Seed, 1987; Knapp et al., 1989). Further studies are now needed to define the physical and functional relation of the epitopes and establish whether antibody-mediated activation corresponds with that noted in humans. Data reported in one study (Baldwin et al., 1988) with IL-A26 suggest possible differences in the requirements for activation. In addition, further studies are needed to demonstrate how many cell types express BoCD2. In mice, evidence has been presented which shows the mouse orthologue is expressed on some B cells (Yagitta et al., 1989). Studies in cattle have clearly shown CD2 is present on the majority of CD4+ and CD8+ T-cells and a small population of CD4-/CD8- cells (Baldwin et al., 1988; Davis, unpublished observations). Evidence presented in this workshop has shown that some CD2+ cells express a WC2 molecule (Sopp et al., 1991).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
99.
In vitro methylcellulose cultures of bovine bone marrow progenitor cells were developed. An existing technique described for bovine species was compared to a method for human tissue and further adapted during subsequent experiments. Bovine bone marrow samples were collected at the slaughterhouse, and mononuclear cells were separated by gradient centrifugation (1.077 g/ml specific density and 400 g). The use of 3% bovine leucocyte-conditioned medium, produced by stimulation of blood lymphocytes with 4 microg/ml concanavalin A and harvested on day 4 of culture, gave better results than the use of supernatant of the human bladder carcinoma 5637, which is widely used in human bone marrow cultures. However, bovine leucocyte-conditioned medium was not added to erythroid cultures because inhibitory effects were observed. Erythroid colonies were stimulated with erythropoietin, and hemin was added to enable microscopic identification. Reduced oxygen tension was necessary to induce growth of erythroid colonies. This was not necessary for myeloid cultures. In conclusion, the results of this study show that the growth of myeloid and erythroid colonies in methylcellulose-based medium requires different culture conditions, which are different from the culture conditions for human cells.  相似文献   
100.
OBJECTIVE: To evaluate disposition of butorphanol after i.v. and i.m. administration, effects on physiologic variables, and analgesic efficacy after i.m. administration in llamas. DESIGN: Nonrandomized crossover study. ANIMALS: 6 healthy adult male llamas. PROCEDURE: Butorphanol (0.1 mg/kg [0.045 mg/lb] of body weight) was administered i.m. first and i.v. 1 month later. Blood samples were collected intermittently for 24 hours after administration. Plasma butorphanol versus time curves were subjected to pharmacokinetic analysis. Two months later, butorphanol (0.1 mg/kg) was administered i.m., and physiologic variables and analgesia were assessed. RESULTS: Extrapolated peak plasma concentrations after i.v. and i.m. administration were 94.8 +/- 53.1 and 34.3 +/- 11.6 ng/ml, respectively. Volume of distribution at steady state after i.v. administration was 0.822 +/- 0.329 L/kg per minute and systemic clearance was 0.050 +/- 0.014 L/kg per minute. Slope of the elimination phase was significantly different, and elimination half-life was significantly shorter after i.v. (15.9 +/- 9.1 minutes) versus i.m. (66.8 +/- 13.5 minutes) administration. Bioavailability was 110 +/- 49% after i.m. administration. Heart rate decreased and rectal temperature increased. Somatic analgesia was increased for various periods. Two llamas became transiently sedated, and 2 became transiently excited after butorphanol administration. CONCLUSIONS AND CLINICAL RELEVANCE: Although i.v. administration of butorphanol results in a short half-life that may limit its analgesic usefulness, the elimination half-life of butorphanol administered i.m. is likely to be clinically useful. The relationship among plasma butorphanol concentration, time, and analgesia differed with the somatic analgesia model; clinically useful analgesia may occur at lower plasma concentrations than those reported here.  相似文献   
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