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排序方式: 共有418条查询结果,搜索用时 78 毫秒
91.
LI Dong-yin c CHU Zhong-hua WAN Yun-le SHAO Jing WEI Jing LIU Shan-ying ZHENG Li-min OU Qing-jia 《园艺学报》2005,21(5):906-910
AIM: To investigate the immune stimulation capacity of B7-H1 blockade on immature dendritic cells (DCs) in vitro. METHODS: The human monocyte-derived dendritic cells were induced in the presence of cytokine GM-CSF and IL-4. The expression of B7-H1 was detected by FCM. On blockade of B7-H1, the maturation and endocytic activity, T cells stimulatory proliferation capacity, IL-12 production, T cell differentiation effect of DCs were detected by FCM, MTT assay, ELISA and ELISPOT, respectively. RESULTS: The expression of B7-H1 was increased with the induction of DCs. On day 7, the positive expression was 54.12%, and the TNF-α induced mature DCs had the positive expression rate of 83.64%. The blockade of B7-H1 on immature DCs had sharply increased their T cells stimulatory proliferation capacity and IL-12 production, and efficiently induced the development of Th1/Tc1 cells, but had no effect on their maturation and endocytic activity. CONCLUSION: The blockade of B7-H1 on immature DCs increases its immune stimulation activity. It is valuable to investigate the antitumor immune responses of DCs vaccine with B7-H1 blockade. 相似文献
92.
A statistically representative group of human population from the South Moravian region (CSSR) was examined on the presence of antibodies against the following arboviruses: Lednice, Sindbis, tick-borne encephalitis, West Nile, Tahyna and Calovo. The ascertained absence of antibodies to the Lednice virus is an evidence that at present this virus is of no epidemiological importance in the region studied. No antibodies to Sindbis, West Nile and Calovo viruses were demonstrated. 17.8 to 42.0% of antibodies to Tahyna virus were detected in all age groups examined. The total infection rate was 26.0%. Antibodies to the tick-borne encephalitis virus occurred primarily in persons over 40 years. The total infection rate was 5.5%. 相似文献
93.
Tadeusz Garbuliński 《Veterinary research communications》1983,7(1):369-375
Using fenylephrine, isoprenaline, noradrenaline, adrenaline and receptor blockers, adrenergic regulation of metabolism in working heart as well as in skeletal resting muscle of rats was investigated. Changes were determined in: phosphocreatine level and32P incorporation into phosphocreatine; phosphorolytic and hydrolytic activities of glycogenolysis; glycogen synthetase activity and14C-glucose incorporation into glycogen; and the level of cAMP. It was found that, contrary to the β-receptor, stimulation of the α-adrenergic receptor inhibits catabolism of macroenergetic phosphates and diminishes glycogen decomposition on the phosphorolytic pathway while increasing the hydrolysis of glycogen and glycogen synthetase activity as well as glucose incorporation into glycogen. On the basis of these data a hypothesis may be put forward that the influence of the α-adrenergic receptor results in the diminishing of energy utilization and in the activation of glycogen anabolism in heart and skeletal muscle. An adrenergic intrasystemic receptor antagonism in the regulation of energy consumption by heart and skeletal muscle is indicated. The α-receptor seems to be an adrenergic intrasystemic moderator of the metabolism rate which is accelerated by β-receptor influence. This suggests that besides sympathetico-parasympathetic intersystemic antagonism regulating the heart work and thereby cardiac energy consumption, there is a separate adrenergic mechanism directly controlling the balance between catabolism and anabolism in heart muscle. This mechanism, based on α- and β-adrenergic receptor antagonism, also controls the metabolic balance in skeletal muscles. 相似文献
94.
Prevalence of antimicrobial resistance in fecal generic Escherichia coil isolated in western Canadian beef herds. Part II--cows and cow-calf pairs. 下载免费PDF全文
Sheryl P. Gow Cheryl L. Waldner Andrijana Rajíc Margaret E. McFall Richard Reid-Smith 《Canadian journal of veterinary research》2008,72(2):91-100
The objective of this study was to describe antimicrobial resistance in fecal generic Escherichia coli isolated from cows and cow-calf pairs from western Canadian beef herds. Susceptibility testing was completed on 1555 E. coli isolates (n = 533 cows from 69 herds) harvested from fresh fecal samples in the spring of 2002, and 630 isolates (n = 105 cow-calf pairs from 10 herds) collected in the spring of 2003. Only 1 cow isolate was resistant to an antimicrobial classified by Health Canada as being of very high importance to human medicine. Resistance to at least 2 antimicrobials was detected in 7.1% of the 2002 cow isolates, in 3.4% of the 2003 cow isolates, and 23.2% of the 2003 calf isolates. In the cows, resistance to at least 1 antimicrobial was not associated with cow breed (P = 0.16), cow age (P = 0.14), or previous cow treatment (P = 0.56). In the calves, resistance to at least 1 antimicrobial was not predicted by whether or not its dam was resistant to at least 1 antimicrobial (P = 0.36). 相似文献
95.
Martin Kvác Bohumil Sak Dana Kvetonová Oleg Ditrich Lada Hofmannová David Modry Jirí Vítovec Lihua Xiao 《Veterinary parasitology》2008,153(3-4):363-367
Farm ruminants were infected experimentally with four mammalian gastric Cryptosporidium, namely Cryptosporidium andersoni LI03 originated from cattle and three isolates of Cryptosporidium muris from brown rat (isolate RN66), Bactrian camel (isolate CB03) and firstly characterized isolate from East African mole rat (isolate TS03). Sequence characterizations of the small-subunit rRNA gene showed that the LI03 isolate was C. andersoni and the other three isolates belonged to C. muris, although the TS03 isolate showed unique sequence variations (one single nucleotide change and four nucleotide insertions). C. andersoni LI03 was infectious for calves only, whereas lambs and kids were susceptible to C. muris CB03. C. muris TS03 and RN66 were not infectious for any farm ruminants. Infection dynamics including prepatent and patent period and infection intensity of the isolates used differed depending on the host species, but no clinical signs of cryptosporidiosis were observed in any of experimentally infected hosts. Cryptosporidium developmental stages were only detected in infected animals in the abomasum region. Histopathological changes were characterized by dilatation and epithelial metaplasia of infected gastric glands with no significant inflammatory responses in the lamina propria. 相似文献
96.
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99.
A group of six lambs at the age of two months and of the average weight of 13 kg were invaded with the larvae Haemonchus contortus and Trichostrongylus colubriformis; the course of invasion was compared with that in a group of four control lambs. In regular ten-day intervals, some hematological indices, proteinemia. SGOT and SGPT activities, glucose level, sodium and potassium were studied in blood samples; at the same time egg elimination was observed in excrement samples. The invasion intensity was checked by helminthological dissection of an experimentally invaded lamb 35th day p.i.; 576 H. contortus adults and 398 T. colubriformis adults were determined. Egg number recalculated per 1 g excrements (E.P.G.) amounted to 3072. At that stage, both groups were administered mebendazole at a dose of 10 mg active substance per 1 kg live weight on three successive days. The efficacy of the treatment (IE) was 97.01 to 98.05%. According to the clinical examination the hematocrit level dropped statistically significantly on the ninth day p.i., the other indices under study showed no changes. The drug administration increased temporarily the erythrocyte count and decreased MCV and MCH. Although mebendazole mainly inhibited glucose metabolism in the nematodes, the drug administration did not influence the glucose level of the host's blood serum. 相似文献
100.