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221.
Summary 2 populations of rat fleas,Xenopsylla astia, collected from (A) Bombay and (B) Trivandrum, were found to differ in chromosome number as follows; (A) 2n=10 in both sexes; (B) 2n=18 (male) and 20 (female). Preliminary observations have further shown that the 2 populations differ in certain morphological characters and that their reciprocal hybrids are sterile in the male and partially sterile in the female sex.Acknowledgments. We wish to express our deepest gratitude to Dr Robert E. Lewis, Professor of Entomology, Iowa State University, USA, for confirming our identification of the 2 samples of rat fleas. We are indebted to Dr N.R. Prabhoo, Reader in Zoology, University of Kerala, Trivandrum, for his advice and helpful suggestions. We are also indebted to Prof. K.M. Alexander, for encouragement and providing facilities. Financial help of the University Grants Commission, India, to one of us (C.T.) is also gratefully acknowledged. 相似文献
222.
Summary The seedling growth ofBrassica campestris var.varuna, has been studied, as affected by water-stress and gibberellin treatments. A boost in the net GA response due to water-stress, has been observed. Thus presence of GA can overcome the water-stress effects.Publication No. 26 from Dept of Biosciences, Himachal Pradesh University, Simla. Authors are grateful to CSIR, New Delhi, for JRF to SB. 相似文献
223.
D. K. Bhatt 《Cellular and molecular life sciences : CMLS》1978,34(12):1549-1550
Summary Phenylketonuric squirrels have shown marked inhibition of alkaline phosphatatase in the olfactory lobes and cerebral hemispheres, whereas the Na+-K+-ATPase remained less altered. In the pathogenesis of phenylketonuria inhibition of alkaline phosphatase at the level of Blood-Brain Barrier (BBB), leads transport system to impaired functioning.This work was done in the Department of Zoology, University of Udaipur, Udaipur-313001, India. 相似文献
224.
The effect ofγ-irradiation on soil enzyme stability 总被引:1,自引:0,他引:1
R. G. Burns Lindsay J. Gregory G. Lethbridge N. M. Pettit 《Cellular and molecular life sciences : CMLS》1978,34(3):301-302
Summary Arylsulphatase, -1,3 glucanase, phosphatase and urease responded differently to -irradiation (5–50 Mrad) in air-dried and moist soils. In all instances phosphatase was the most stable. The variability between enzymes may be due to inherent biochemical and stuctural characteristics or to their location within the soil microenvironment.Supported by a grant from the NERC. 相似文献
225.
Large-scale purification of hepatitis B surface antigen using affinity chromatography 总被引:2,自引:0,他引:2
A. R. Neurath A. M. Prince J. Giacalone 《Cellular and molecular life sciences : CMLS》1978,34(3):414-415
Summary Large-scale purification of hepatitis B surface antigen, applicable to the preparation of potential vaccines for prevention of hepatitis B, is described. The method involves the following steps: precipitation of serum with polyethylene glycol 6000, affinity chromatography on concanavalin A-Sepharose and on -aminononyl-Sepharose, and isopycnic centrifugation.This study was supported by grant 09011 from the National Heart, Lung and Blood Institute. We thank Dr. B. Hollinger for testing HBsAg samples by a complement fixation test. 相似文献
226.
R Lang 《Experientia》1978,34(4):500-501
Moxnidazole [3-(5-nitrol-1-methyl-2-imidazolyl)-methyleneamino-5-morpholinomethyl-2-oxazolidinone, HCl], known to be mutagenic in microbial tests and Drosophila, induced genetic alterations in somatic cells of mice. Ethyl methanesulfonate (EMS) served as positive control. 相似文献
227.
D K Bhatt 《Experientia》1978,34(12):1549-1550
Phenylketonuric squirrels have shown marked inhibition of alkaline phosphatase in the olfactory lobes and cerebral hemispheres, whereas the Na+-K+-ATPase remained less altered. In the pathogenesis of phenylketonuria inhibition of alkaline phosphatase at the level of "Blood-Brain Barrier" (BBB), leads transport system to impaired functioning. 相似文献
228.
Rana esculenta (L.), kept under natural conditions, show almost constant body weights in the annual cycle. Fat body weight, however, has a distinct maximum in October decreasing continuously to a May minimum which is also evident in the fat body index. The triglyceride and protein contents show the same course. Suprisingly high amounts of glycogen are found, which reach a maximum in August. 相似文献
229.
D Viala E Freton 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1980,291(6):573-576
In curarized Rabbits whose cervico-thoracic cord has been isolated through C2 and Th12 transections, a pharmacological activation (nialamide-DOPA) disclosed distinct rhythmic efferent activities, locomotor-like bursts in forelimb muscle nerves and "respiratory" discharges in the phrenic nerves: they originate respectively from a cervico-thoracic locomotion generator and from a "respiration" generator; these spinal generators appear to be interconnected with each other. 相似文献
230.