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101.
A genetic linkage map of 96 loci on the short arm of human chromosome 3.   总被引:1,自引:0,他引:1  
We constructed a genetic map of 96 loci on the short arm of human chromosome 3 (3p) in 59 families provided by the Centre d'Etude du Polymorphisme Humaine (CEPH). Twenty-nine continuously linked loci were placed on the map with likelihood support of at least 1000:1; one locus, D3S213, was placed on the map with likelihood support of 871:1; D3Z1, an alpha satellite centromeric repeat probe, was placed on the map with likelihood support of 159:1; 65 loci were assigned regional locations. The average heterozygosity of the uniquely ordered markers was 49%. The map extends from 3p26, the terminal band of 3p, to the centromere (from D3S211 to D3Z1). Multipoint linkage analysis indicated that the male, female, and sex-averaged maps extend for 102, 147, and 116 cM, respectively. The mean genetic distance between uniquely ordered loci on the sex-averaged map was 4.0 cM. Probe density was greatest for the region of 3p between D3F15S2e and the telomere. The sex-averaged map contained two intervals greater than 10 cM. Seventeen probes were localized by fluorescence in situ hybridization. The loci described in this report will be useful in building an integrated genetic and physical map of this chromosome.  相似文献   
102.
R S Bedlack  M Wei  L M Loew 《Neuron》1992,9(3):393-403
Our study explores the mechanisms behind neurite galvanotropism. Using phase, differential interference contrast and ratiometric fluorescence microscopy, we reveal four responses of N1E-115 mouse neuroblastoma cells to 0.1-1.0 mV/microns uniform DC electric fields: cathode-directed neurite initiation and elongation, cathode-biased growth cone filopodial protrusions, transient cathode-localized calcium increases, and persistent cathode-localized membrane depolarizations. These newly demonstrated events are temporally and spatially correlated, suggesting that they are causally related. The calcium increases are prevented by calcium channel blockers and by the removal of extracellular calcium. We therefore propose that the observed field-induced membrane depolarizations activate voltage-dependent calcium channels, resulting in cathode-localized calcium influx. This, in turn, may initiate the observed cathode-biased growth cone filopodial protrusions, followed by the cathode-directed neurite elongation.  相似文献   
103.
A successful simultaneous bilateral forearm revascularization was performed on a 17-year-old boy. Functional recovery of both forearms was evaluated 42 months after injury. The patient can use both hands for the activities of daily living. So far, he has been employed and has no significant psychological problems. Temporary intraluminal silicone shunts are extremely helpful for reducing ischemic damage to the injured limb. The sufficient skeletal shortening of the upper limb replantation is crucially important. The wounds must be managed by aggressive and repeated debridement. Accurate primary nerve repair is essential, and the early postoperative rehabilitation is also important to achieve a satisfactory functional return. The functional replanted or revascularized upper extremity is superior to an amputation or prosthesis, especially in the cases of bilateral upper extremity amputation or devascularization.  相似文献   
104.
Eighteen strains of xylariaceous fungi have been screened for higher activities of cellulolytic enzymes,Trichoderma reesei QM 9414 was also examined for comparison. Strains ofXylaria anisopleura andX. regalis had higher endocellulase (CMCase) and exocellulase (Avicelase) activities after 2 weeks' incubation.Hypoxylon stygium produced the highest activity of -glucosidase 3 days after inoculation. The optimum pH for these cellulolytic enzymes was approx. 5.0 and the optimum temperatures ranged from 37 to 50°C. A mixed culture process usingT. reesei QM 9414 andH. stygium was developed to obtain enhanced synthesis of cellulase. -Glucosidase activities in the mixed culture increased within 48h whenH. stygium was introduced after 24h.  相似文献   
105.
本文记述花螳螂亚科巨腿花螳属二新种:半黑巨腿花螳 Hestiasula seminigra Zhang sp.nov.基黑巨腿花螳H.basinigra Zhang sp.nov.模式标本保存于南京林业大学昆虫标本室。  相似文献   
106.
木薯良种——“南植188”引种试验研究   总被引:1,自引:1,他引:0  
李锋  甘赞琼  韦霄  黄正福   《广西植物》1992,12(3):250-253
本文报道木薯良种——“南植188”引种试验结果。在桂林地区种植“南植188”品种表现长势好,结薯早且多,薯肥大等丰产性能。产量明显高于本地品种,淀粉含量高,纤维素和氢氰酸含量低,是一个有发展前途的高产优质品种。  相似文献   
107.
本文记述了尾孔科吸虫一新种——平睾尾孔吸虫,新种Urotrema parallelorchis sp.nov.。新种采自短身间吸鳅和犁头鳅的肠道。新种的睾丸左右排列而不同于该属的所有已知种。  相似文献   
108.
本文报道作者近年来在石家庄动物园对亚洲象Elephas maximus进行药物驱虫时采集的寄生线虫一新种,无齿奎隆线虫,新种Quilonia edentata sp.nov.,模式标本保存于河北师范大学生物系。  相似文献   
109.
高翔蜉属一新种:蜉蝣目:扁蜉蝣科   总被引:1,自引:1,他引:0  
本文记述采自湖南省大庸市高翔蜉属一新种。该种以其阳茎叶外侧面具有一向前弯曲的钩状突起为显著特征,可区别于本属其他种类。  相似文献   
110.
流式细胞计的研制   总被引:5,自引:3,他引:2  
流式细胞计是近年发展起来的一种综合应用光学机械,电子学,流体动力学,激光和计算机的高技术生物医学仪器。它在生物学基础研究和临床医学研究中有广泛的应用。我们最近研制成功国内首台多参数流式细胞计,并已通过中国科学院院级鉴定。本文介绍该仪器的原理,主要结构与技术要点和使用结果等,它将有助于我国流式细胞术及其应用研究工作的开展。  相似文献   
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