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71.
为了解四川省自贡地区3~5岁幼儿乙型肝炎病毒(HBV)感染情况,并探索与感染有关的因素,1985年调查了1167名幼儿,其HBV总感染率为41.13%,HBsAg阳性率12.68%。幼儿的HBV感染与母亲HBsAg阳性密切相关。共检查母亲409例,38例HBsAg阳性,其幼儿HBsAg阳性率为50%(19/38),HBsAg阴性的母亲371例,其幼儿HBsAg阳性率9.97%(37/371),来自HBsAg阳性母亲的阳性子女占33.3%(19/56)。1986年随访HBV易感幼儿448例,HBV年感染率为12.95%(58/448),HBsAg年阳转率3.79%。HBV年感染率与原幼儿班级HBsAg阳性率的高低有关。 相似文献
72.
新(亚)种的模式标本除标明者外均存作者所在单位。1.贵州棘蝇Phaonia guizhouensis Wei,新种(图1) 雄:体长6mm。眼具淡黄色密长毛。额宽至少等于触角第三节宽。间额黑灰,约为一侧额的5倍宽。侧额狭,粉被暗银灰色。额鬃上达单眼瘤前,仅前方的3对发达,后大半细如眼毛。侧颜黑,下侧颜暗红,粉被银灰;侧颜至少如触角第三节宽之半。触角黑,第三节约为第二节的2倍长。芒短羽状,最长芒毛约为触角宽之半。颊蓝黑,粉被灰褐,前上缘具一列上弯的鬃;颊约如眼高的2/7。口上片突出于额前缘。中颜板 相似文献
73.
据我们在北京和内蒙古等地多年研究表明,黄芪的植食性种子小蜂包括广肩小蜂科Bruchophagus属5种和金小蜂科Habrocytus属1种,为多种混合群体。我们通过大量标本的形态比较以及交配行为的观察,结合其生物学特性研究以及应用扫描电镜对其并胸腹节花纹的超微结构观察,鉴定出黄芪种子里有5种广肩种子小蜂,即黄芪种子小蜂Bruchophagus huonchi Liao et Fan及本文的4新种。 相似文献
74.
角胫象属Shirahoshizo Morimoto,1962隶属象虫科隐喙象亚科,模式种为Cryptorhynchus rufescens Roelofs.本属昆虫多寄生于松属植物,有些是我国重要林业害虫,如马尾松角胫象Shiraho shizo flavonotatus(Voss),其成虫侵入衰弱的黄山松和堆积的马尾松原木,和其它钻蛀性害虫一起,造成严重危害,据浙江亚热带林研所赵锦年先 相似文献
75.
本文选用金黄地鼠的微血管,利用显微高速摄影技术,放大微观流场和血细胞,连续地“冻结”短瞬间的变化状态,把物理图象呈现在胶片上,经图像分析和数据处理,从定性及定量方面研究血液微流变学,为生命科学和医学研究提供了又一种新的方法。 相似文献
76.
本文报道了寄生在云杉上的中国新记录种顶裂盘菌(Lophophacidium hyperboreumLagerb.);首次发现了这个种的无性型座壳梭孢属(Apostrasseria sp.),证实了融雪前病株针叶上有表生的菌丝和小菌核;查清了它是新疆云杉林中的广布种,引致云杉雪枯病;发现了新分布区,地理分布范围在75°—94°E,37°40′—49°N;发现了新寄主,多土的西伯利亚云杉(Picea obovata Ledeb.)和引进的青海云杉(P.crassifolia Kom.)、川西云杉(P.balfourianaRehd.et Wils.)。 相似文献
77.
A Skogl?f I Nilsson S Gustafsson J Deinum P O G?the 《Biochimica et biophysica acta》1990,1041(1):22-30
The angiotensin I-converting enzyme (peptidyl-dipeptide hydrolase, EC 3.4.15.1) inhibitor, ramiprilat (2-[N-[(S)-1-ethoxycarbonyl-3-phenylpropyl]-L-Ala]-(1S,3S,5S)-2- azabicyclo[3.3.0]octane-3-carboxylic acid), is shown to exist in tow conformational isomers, cis and trans, which interconvert around the amide bond. The two conformers were separated by reversed-phase high-performance liquid chromatography. The conformers were identified by nuclear Overhauser effect measurements. From line shape analysis the isomerization rate constants were determined to be kcis----trans = 15 s-1 and ktrans----cis = 5 s-1 at 368 K in [2H]phosphate buffer (p2H 7.5). By enzyme kinetic studies using 3-(2-furylacryloyl)-L-Phe-Gly-Gly as substrate, the trans conformer was found to be the most potent enzyme inhibitor, whereas the cis conformer had a very low inhibitory effect. A new inhibition mechanism is presented for this type of slow, tight-binding inhibitors that contain an amide bond. This mechanism involves an equilibrium between the two conformers and the enzyme-bound inhibitor complex. 相似文献
78.
Chantal Jeanne Beauchamp William Scott Chilton Patrice Dion Hani Antoun 《Applied microbiology》1990,56(1):150-155
This study was conducted to determine the capacities of 37 fungi to utilize various crown gall opines as their sole carbon and nitrogen source. One strain of Fusarium solani, two of Cylindrocarpon destructans, and six of Cylindrocarpon heteronema catabolized octopine, mannopine, octopinic acid, succinamopine, or a combination of these opines. One C. heteronema and one Fusarium dimerum strain grew only on succinamopine. None of the fungal isolates had the ability to grow on nopaline. The catabolism of opines by fungi was confirmed by the disappearance of the opine from the growth medium and by an increase in final mycelial dry weight with rising initial concentration of test substrate. This study thus shows that the catabolism of opines is not restricted to bacteria. 相似文献
79.
Michael A. Baker Robert N. Taub Walter H. Carter the Toronto Leukemia Study Group 《Cancer immunology, immunotherapy : CII》1982,13(2):85-88
Summary Forty-eight patients with acute myeloblastic leukemia in remission were treated with immunotherapy in addition to remission-maintenance chemotherapy. The first 16 patients were treated with weekly BCG and a leukemia cell vaccine (group 1). The next 32 patients were randomly allocated to receive BCG and a leukemia cell vaccine given once monthly (group 2) or BCG given monthly with no leukemia cell vaccine (group 3). There was no significant difference in remission duration or survival between the randomly allocated groups (2 and 3).Comparisons with group 1 are limited by the non-random allocation to this group, but selection bias was unlikely and clinical features were similar in the three patient groups. No significant difference in remission duration or survival was seen amongst the three groups studied. There was no advantage in the addition of leukemia cell vaccine (groups 1 and 2) to BCG alone (group 3) and no advantage to weekly (group 1) versus monthly immunotherapy (groups 2 and 3). Only 7 of the 48 patients achieved a second remission, and 4 of these were short-term partial remissions.The following are contributing members of the Toronto Leukemia Study Group: Doctor's Hospital, Harvey Silver MD; Humber Memorial Hospital, Alan Seidenfeld MD; Mississauga Hospital, Michael King MD; Mount Sinai Hospital, Dominic Amato MD; Northwestern Hospital, Wilhelm Kwant MD; Oshawa General Hospital, Hak Chiu MD; St Michael's Hospital, Bernadette Garvey MD, Kenneth Butler MD; St Joseph's Hospital, H. James Watt MD, Murray Davidson MD; Toronto General Hospital, Gerald Scott MD, William Francombe MD, Kenneth Shumak MD; John Crookston MD, PhD; Toronto Western Hospital, James G. Watt MD, David Sutton MD; Michael Baker MD; Domenic Pantalony MD; Wellesley Hospital, Dale Dotten MD; Women's College Hospital, George Kutas MD; York Finch Hospital, Sam Berger MD 相似文献
80.
Summary Following a 5 hours ethylene treatment, cortical cells of Pea (Pisum sativum L. var Alaska) epicotyl third internode showed a change in the orientation of both microtubules near the plasma membrane and recently deposited cellulose microfibrils. Control cortical cells had mostly transverse microtubules. The ratio of the average frequency of transverse to longitudinal microtubules was 6.0. After 5 hours of ethylene treatment, cortical cells had mostly longitudinal microtubules, with the ratio of transverse to longitudinal microtubules equal to 0.1. Epidermal cells were more variable than cortical cells with regard to the frequency of longitudinal and transverse microtubules. Observation of cortical cell walls in conventionally stained thin sections revealed that recent deposition of microfibrils had been primarily transverse in almost all of the control cortical cells sampled. In contrast, more than half of the ethylene-treated cortical cells had recent deposition oriented primarily longitudinally. This change in microtubule and microfibril orientation may be early enough to constitute the primary effect of ethylene leading to radial cell expansion.Research supported by NSF grant PCM 78-03244, A1, 2 to PBG and by a Research Corporation grant to WRE. 相似文献