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61.
62.
Seven balloons were launched successfully from Ascension Island in January 1969. The balloons, flown at altitudes of 20 and 24 kilometers, will make possible a detailed analysis of the stratospheric circulation near the equator and will hopefully lead to an understanding of the quasi-biennial stratospheric oscillation in the tropics. 相似文献
63.
64.
Reed AC 《Science (New York, N.Y.)》1930,72(1877):611-620
65.
Gregory SM Davis BK West JA Taxman DJ Matsuzawa S Reed JC Ting JP Damania B 《Science (New York, N.Y.)》2011,331(6015):330-334
The NLR (nucleotide binding and oligomerization, leucine-rich repeat) family of proteins senses microbial infections and activates the inflammasome, a multiprotein complex that promotes microbial clearance. Kaposi's sarcoma-associated herpesvirus (KSHV) is linked to several human malignancies. We found that KSHV Orf63 is a viral homolog of human NLRP1. Orf63 blocked NLRP1-dependent innate immune responses, including caspase-1 activation and processing of interleukins IL-1β and IL-18. KSHV Orf63 interacted with NLRP1, NLRP3, and NOD2. Inhibition of Orf63 expression resulted in increased expression of IL-1β during the KSHV life cycle. Furthermore, inhibition of NLRP1 was necessary for efficient reactivation and generation of progeny virus. The viral homolog subverts the function of cellular NLRs, which suggests that modulation of NLR-mediated innate immunity is important for the lifelong persistence of herpesviruses. 相似文献
66.
Solar tracking has been described in several agronomic and wild species, yet variation within a given species has not been reported. To address that issue, photoperiod leaflet reorientation in response to vectorial light was measured in three alfalfa ( Medicago sativa L.) germplasm pools selected from the cultivar Ladak 65. Dark-leaf germplasm responded to all photosynthetic photon flux densities (PPFD) (100 to 700 μmol/m2 /s) with no detectable lag period. Following a 24-h dark treatment only high PPFD (600 to 700μmol/m2 /s) elicited reorientation. Pale-leaf germplasm responded to intermediate (300 to 400 μmol/m2 /s) and high PPFD in a similar manner; however, the low (100-125μmol/m2 /s) PPFD treatment had little effect on reorientation. The 24-h dark treatment decreased reorientation at all PPFD. Small-leaf germplasm responded equally to all PPFD and was not affected by the 24-h dark treatment. The results suggest that available energy levels may influence the reorientation response. Carbonyl cyanide m -chlorophenylhydrazone, an inhibitor of photophosphorylation, and 3-(3,4-dichlorophenyl)-1,1-dimethylurea, an inhibitor of non-cyclic photosynthetic electron transport, reduced reorientation only in the pale-leaf type. These results suggest that stored energy reserves were adequate to maintain leaflet reorientation in the absence of photosynthesis in all but the pale-leaf germplasm. In that germplasm photosynthetically generated energy may be required to support reorientation. 相似文献
67.
68.
Systemic form of infectious bovine rhinotracheitis in young calves 总被引:11,自引:0,他引:11
D E Reed E J Bicknell R J Bury 《Journal of the American Veterinary Medical Association》1973,163(7):753-755
69.
Frequency and severity of osteochondrosis in horses with cervical stenotic myelopathy 总被引:1,自引:0,他引:1
We compared the frequency and severity of osteochondrosis lesions in young Thoroughbred horses with cervical stenotic myelopathy (CSM) vs that in clinically normal Thoroughbreds of the same age. All lesions of the cervical vertebrae and appendicular skeleton were classified histologically as osteochondrosis or nonosteochondrosis and were measured for severity. Minimal sagittal diameter was significantly smaller in horses with CSM from C2 through C6; no difference was detected at C7. Severity of cervical vertebral osteochondrosis was greater in the horses with CSM, however frequency was not different. Frequency and severity of nonosteochondrosis lesions were not different in cervical vertebrae or appendicular skeleton. Frequency and severity of appendicular skeleton osteochondrosis lesions were both greater in horses with CSM. Osteochondrosis and nonosteochondrosis lesions were more severe on facets at sites of compression than on facets at noncompressed sites in horses with CSM. However, compression was also observed at sites with no articular facet lesions. The association of widespread osteochondrosis and spinal canal narrowing with CSM suggests CSM may represent a systemic failure in the development or maturation of cartilage and bone. 相似文献
70.
Embryo transfer for conserving valuable genetic material from swine herds with pseudorabies 总被引:1,自引:0,他引:1
J E James D M James P A Martin D E Reed D L Davis 《Journal of the American Veterinary Medical Association》1983,183(5):525-528
Embryo transfer was used to conserve genetic material from 2 swine herds seropositive for pseudorabies virus (PRV). Embryos (n = 805) were recovered from 38 PRV-seropositive Duroc sows in Iowa and, after 4 to 10 hours' culture and shipment to Illinois, were transferred to 34 recipients from a herd seronegative for PRV. All recipients remained seronegative for PRV, and 22 of the recipients farrowed 208 pigs (189 alive) that also were seronegative for PRV. There was no evidence of PRV in the embryo recovery medium or in the uterine and oviductal cells recovered with the embryos. Transfer of morulae resulted in higher (P less than 0.02) farrowing rates than did transfer of 4- to 8-cell embryos, but litter size was not affected. 相似文献