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41.
42.
Masaaki Katayama Yasuhiko Okamura Rieko Katayama Jun Sasaki Shunsuke Shimamura Yuji Uzuka Hiroaki Kamishina Yoshinori Nezu 《The Canadian veterinary journal. La revue veterinaire canadienne》2013,54(4):381-386
A 12-year-old, 3.5-kg spayed female domestic shorthair cat had a tracheal mass identified as malignant B-cell lymphoma. The cat had tracheal resection and subsequently developed laryngeal paralysis. Due to multiple episodes of respiratory distress the cat subsequently had tracheal surgeries. Finally, the cat had a sudden onset of severe respiratory distress and collapsed. Computed tomography imaging and arterial blood gas analysis supported a diagnosis of acute lung injury. 相似文献
43.
Establishment of an attenuated strain of bovine respiratory syncytial virus for live virus vaccine 总被引:1,自引:0,他引:1
M Kubota S Fukuyama K Kodama N Sasaki 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1990,52(4):695-703
To develop a live virus vaccine for the prevention of bovine respiratory syncytial (BRS) virus infection in calves, an attempt was made to produce an attenuated virus. The RS-52 strain of BRS virus, isolated from the nasal secretions of a naturally infected calf, was subjected to serial passages in adult hamster lung established (HAL) cells at 30 degrees C and the attenuated rs-52 strain as a live virus vaccine was established. The rs-52 strain multiplied better at 30 degrees C than at 34 or 37 degrees C in HAL cells. The differences in the highest virus titers of this strain between the culture temperature of 30 degrees C and that of 34 or 37 degrees C were more than 2.25 log TCID50. Colostrum-deprived newborn calves and 2 approximately 4 months old calves inoculated with the rs-52 strain manifested no abnormal clinical sings at all. However, all inoculated calves produced serum neutralization antibody. When the colostrum-deprived newborn calves immunized with the rs-52 strain were challenged with the virulent NMK7 strain of BRS virus, they exhibited no pyrexia or other abnormal clinical signs at all. An attempt was made to recover the virus from nasal secretions of these calves, but in vain. On the other hand, a nonimmunized control colostrum-deprived newborn calf developed slight fever, mild cough, and slight serous nasal discharge after challenge exposure. The virus was recovered from nasal secretions of this calf. From these results, it was considered that the rs-52 strain could be used as an attenuated live virus vaccine for prevention of BRS virus infection. 相似文献
44.
45.
The mutual control of the electric and magnetic properties of a solid is currently of great interest because of the possible application for novel electronic devices. We report on the low-magnetic-field (for example, B values of +/-30 milliteslas) control of the polarization (P) vector in a hexaferrite, Ba2Mg2Fe12O22, which shows the helimagnetic spin structure with the propagation vector k0 parallel to [001]. The B-induced transverse conical spin structure carries the P vector directing perpendicular to both B and k0, in accord with the recently proposed spin-current model. Then, the oscillating or multidirectionally rotating B produces the cyclic displacement current via the flexible handling of the magnetic cone axis. 相似文献
46.
Induction of AIDS in rhesus monkeys by molecularly cloned simian immunodeficiency virus 总被引:92,自引:0,他引:92
H Kestler T Kodama D Ringler M Marthas N Pedersen A Lackner D Regier P Sehgal M Daniel N King 《Science (New York, N.Y.)》1990,248(4959):1109-1112
Better understanding of the pathogenesis of acquired immunodeficiency syndrome (AIDS) would be greatly facilitated by a relevant animal model that uses molecularly cloned virus of defined sequence to induce the disease. Such a system would also be of great value for AIDS vaccine research. An infectious molecular clone of simian immunodeficiency virus (SIV) was identified that induces AIDS in common rhesus monkeys in a time frame suitable for laboratory investigation. These results provide another strong link in the chain of evidence for the viral etiology of AIDS. More importantly, they define a system for molecular dissection of the determinants of AIDS pathogenesis. 相似文献
47.
Nakagawa T Kitagawa H Yasuda Y Tarasov PE Nishida K Gotanda K Sawai Y;Yangtze River Civilization Program Members 《Science (New York, N.Y.)》2003,299(5607):688-691
Pollen records from the annually laminated sediment sequence in Lake Suigetsu, Japan, suggest a sequence of climate changes during the Last Termination that resembles that of the North Atlantic region but with noticeable differences in timing. An interstadial interval commenced a few centuries earlier [approximately 15,000 years before the present (yr B.P.)] than the North Atlantic GI-1 (B?lling) event. Conversely, the onset of a Younger Dryas (YD)-like cold reversal (12,300 to 11,250 yr B.P.) postdated the North Atlantic GS-1 (YD) event by a few centuries. Climate in the Far East during the Last Termination reflected solar insolation changes as much as Atlantic influences. 相似文献
48.
Kodama S Kühtreiber W Fujimura S Dale EA Faustman DL 《Science (New York, N.Y.)》2003,302(5648):1223-1227
Nonobese diabetic (NOD) mice are a model for type 1 diabetes in humans. Treatment of NOD mice with end-stage disease by injection of donor splenocytes and complete Freund's adjuvant eliminates autoimmunity and permanently restores normoglycemia. The return of endogenous insulin secretion is accompanied by the reappearance of pancreatic beta cells. We now show that live donor male or labeled splenocytes administered to diabetic NOD females contain cells that rapidly differentiate into islet and ductal epithelial cells within the pancreas. Treatment with irradiated splenocytes is also followed by islet regeneration, but at a slower rate. The islets generated in both instances are persistent, functional, and apparent in all NOD hosts with permanent disease reversal. 相似文献
49.
Matsubara H Yoshimoto S Saito H Jianglin Y Tanaka Y Noda S 《Science (New York, N.Y.)》2008,319(5862):445-447
Shorter-wavelength surface-emitting laser sources are important for a variety of fields, including photonics, information processing, and biology. We report on the creation of a current-driven blue-violet photonic-crystal surface-emitting laser. We have developed a fabrication method, named "air holes retained over growth," in order to construct a two-dimensional gallium nitride (GaN)/air photonic-crystal structure. The resulting periodic structure has a photonic-crystal band-edge effect sufficient for the successful operation of a current-injection surface-emitting laser. This represents an important step in the development of laser sources that could be focused to a size much less than the wavelength and be integrated two-dimensionally at such short wavelengths. 相似文献
50.
Rina KIHARA Yoshinori KASASHIMA Katsuhiko ARAI Yasunori MIYAMOTO 《Journal of Equine Science》2011,22(3):57-60
Injury initiates a repair process characterized by influx of fibroblasts and the rapid
formation of fibrous scar tissue and subsequent tissue contraction. The response to injury
and behavior of the different tendon fibroblast populations, however, has been poorly
characterized. We hypothesized that the fibroblasts recovered from tendon with acute
injury would exhibit different cell properties relating to adhesion, migration and
tensegrity. To test this hypothesis we evaluated the ability of fibroblasts recovered from
normal and injured equine superficial digital flexor tendons (SDFTs). The injured
tendon-derived cells showed greater contraction of the collagen gel but poorer adhesion to
pepsin-digested collagen, and migration over extracellular matrix proteins compared to
normal SDFT-derived fibroblasts. Thus, the cells present within the tendon after injury
display different behavior related to wound healing. 相似文献