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91.
92.
Identification and eradication of Menangle virus from pigs   总被引:1,自引:0,他引:1  
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93.
The objective of this study was to elucidate the kinetics and magnitudes of specific IgA antibody responses in intestines of turkey poults infected with turkey coronavirus (TCV). Turkey poults were orally inoculated with TCV at 10 days of age. Intestinal segment cultures were administered for duodenum, jejunum, and ileum and the IgA antibody responses were analyzed at 1, 2, 3, 4, 6, or 9 weeks post-infection (PI) in two different experiments. The kinetics of virus-specific IgA antibody responses in duodenum, jejunum, and ileum were similar: gradually increased from 1 week PI, reached the peak at 3 or 4 weeks PI, and declined afterward. The virus-specific IgA antibody responses in duodenum, jejunum, and ileum showed negative correlation with duration of TCV antigen in the corresponding locations of intestine with Spearman's correlation coefficient of -0.85 (p=0.034), -0.74 (p=0.096), and -0.75 (p=0.084), respectively. Moreover, the virus-specific IgA antibody responses in serum were positively correlated with that of duodenum (coefficient=0.829, p=0.042), jejunum (coefficient=0.829, p=0.042), and ileum (coefficient=0.771, p=0.072) segment cultures, suggesting that the induction of specific IgA response in serum was predictive of an IgA response in intestine. The results indicate that intestinal mucosal IgA antibodies to TCV are elicited in turkeys following infection with TCV. The local mucosal antibodies may provide protective immunity for infected turkeys to recover from TCV infection.  相似文献   
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The objective of the present study was to evaluate the quality of bovine embryos cryopreserved in different years in Chiapas, Mexico. The embryos were obtained from a government institution (FIMEGEN) dedicated to promoting embryo transfer among dual-purpose cattle farmers. Forty-three embryos frozen in 1988, 1989, 2000 and 2002 were analysed with the Tunel technique to detect programmed cell death (apoptosis). Eleven fresh embryos were used as controls. Analysis of variance was used in embryos stored in the different years with averages tested using Tukey's test. Student's t-test was employed to compare fresh and frozen cells. Embryos with shorter storage time presented a lower number (p < 0.001) of Tunel-positive cells compared with embryos stored for longer time. On the contrary, when comparing the number of apoptotic cells between frozen and fresh embryos a higher number of positive cells (p < 0.05) were found in the former. The present results suggest that the cryopreservation per se caused damage that compromises the viability of the embryo. Another explanation for the lower pregnancy rate found in the tropics could be irreversible damage caused by poor storage technique in these large operations.  相似文献   
98.
The synthesis of novel, fluorinated non-ester pyrethroids by electrophilic fluorination of a stabilised anion with N-fluorobenzenesulfonimide is reported. © 1999 Society of Chemical Industry  相似文献   
99.
The global endemic of cardiovascular diseases calls for improved risk assessment and treatment. Here, we describe an association between myocardial infarction (MI) and a common sequence variant on chromosome 9p21. This study included a total of 4587 cases and 12,767 controls. The identified variant, adjacent to the tumor suppressor genes CDKN2A and CDKN2B, was associated with the disease with high significance. Approximately 21% of individuals in the population are homozygous for this variant, and their estimated risk of suffering myocardial infarction is 1.64 times as great as that of noncarriers. The corresponding risk is 2.02 times as great for early-onset cases. The population attributable risk is 21% for MI in general and 31% for early-onset cases.  相似文献   
100.
Hooper PR 《Science (New York, N.Y.)》1982,215(4539):1463-1468
Between 17 million and 6 million years ago, 200,000 square kilometers of the American Northwest were flooded by basaltic lava that erupted through fissures in the crust up to 150 kilometers long. Larger individual eruptions covered over a third of the Columbia Plateau in a few days. The lavas represent partial melts of the earth's mantle that were only slightly modified by near-surface, upper crustal processes. The abundant chemical and mineralogical data now available offer an opportunity to study mantle composition and the processes involved in the evolution of the earth's crust.  相似文献   
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