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241.
B. K. Sharma 《Hydrobiologia》1979,65(1):39-47
This paper deals with 25 eurotatorien species (spread over eleven families) collected from Calcutta and its environs (Lower Bengal). Of these, 18 species represent new records from this state while six of them are new records from India. 相似文献
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243.
The blood of two fresh water cobitids — Botia lohachata, an exclusive water breathing form and Lepidocephalus guntea a dual breather, — showed a comparatively higher range of Hb (16.0–19.0 g%), Hct (50.0–61.1%) and number of RBC (2.71–6.7 millions/mm3) than many other water and air breathing fishes. Significant sexual difference exists in these characteristics (P > 0.05).The impact of life in oxygen depleted water, also inhabited by L. guntea as a result of its air breathing habit, is well reflected in its greater RBC size (11.86 × 8.66 µm) and their larger surface area (83.96 µm2) compared to that of Botia (53.16 µm2). The smaller size (9.92 × 6.45 µm) and consequently greater number of erythrocytes (4.67 millions/mm3) in Botia, are related to its active mode of life in the swiftly flowing water of hilly rivers. Though the higher nucleo-cytoplasmic ratio of 1 : 5.2 in Botia and 1 : 6.9 in Lepidocephalus suggest a slower red cell metabolism, the greater number of erythrocytes seems to have compensated for their active mode of life. 相似文献
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Two new lecanid rotifers from India 总被引:5,自引:5,他引:0
B. K. Sharma 《Hydrobiologia》1978,60(2):191-192
While working on the material collected from Calcutta and its environs, the author came across two new lecanid rotifers which have been described in this paper as a new species and a new variety. 相似文献
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P N Sharma 《Zeitschrift für Parasitenkunde (Berlin, Germany)》1976,49(3):223-231
Out of other functions performed by vitellaria in digenetic trematodes, their role in the formation of shell globules and shell membrane of the capsule, as well as in the excretion of iron with the help of vitamin C is very important. The present histochemical work shows the localization of certain enzymes in different parts of the reproductive system of ten species of trematodes viz.: Neopronocephalus triangularis Mehra, 1932; Glossimetra orientalis Mehra, 1937; Orientodiscus lobatus Srivastava, 1938; Eumegacetes artemii Mehra, 1935; Ganeo tigrinus mehra et Negi, 1928; Encyclometra caudata Dollfus, 1928; Thapariella udaipurensis Gupta and Sharma, 1970; Paradistomoides indicum Narain et Das, 1929; Patagifer wesleyi Verma, 1936; Proalarioides tropidonotus Vidyarthi, 1937 and indicates their functional significance. The hydrolytic enzymes (alkaline phosphatase, acid phosphatase, 5-nucleotidase and ATPase) are suggestive of their involvement in the uptake of certain nutrients, glycogen and lipoprotein being very significant among others. The four enzymes could also be detected in testes, ovary, uterus, cirrus sac and egg shell. The possible functional significance of each enzyme has been discussed. 相似文献
248.
Hemoglobin-A2-Coburg or alpha2delta2-116 Arg leads to His (G18) has been found in members of a family of Sicilian origin. The propositus is heterozygous for hemoglobin-A2-Coburg as well as for beta-thalassemia, and family data indicate that the gene for the delta-Coburg chain is in trans of the beta-thalassemia determinant. 相似文献
249.
Genetic and developmental studies of wingless (wg1), a new second chromosome recessive mutation in Drosophila melanogaster, have shown that it affects not only wing and haltere development (giving rise to wingless and/or halterless flies), but also results in various abnormalities of the mesothorax. The larvae destined to develop into wingless and/or halterless flies possessed underdeveloped mesothoracic and/or metathoracic imaginal discs. 相似文献
250.