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Summary As a part of integrated study of makhana, the mineral contents of the plant parts and the fruits of makhana (Euryale ferox) have been presented here. It has been observed that the fruits were not only rich in minerals but also in protein. The plant parts also contained high amounts of micronutrients. Its fruits are, therefore, a good supplement for minerals which are produced from otherwise agriculturally waste (water-logged) areas.  相似文献   
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The gametocytocidal efficacy of artemisinin (qinghaosu) was evaluated and scanning electron microscopical evidence is given for gametocytocidal action of a single 5-10-mg/kg dose of artemisinin against simian malarial parasite (Plasmodium cynomolgi B). No sporontocidal effect of artemisinin was observed.  相似文献   
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The GRP receptor mediated growth response in Swiss 3T3 cells has been used to identify BN/GRP antagonists. Analysis of bombesin antagonism by substance P analogues and by truncated GRP analogues revealed that deletion of the C-terminal methionine residue was important for antagonism. Des-Met analogues showing potent antagonist activity in the in vitro 3T3 system (IC50 approximately 2nM) were synthesized. Further structural modification of these peptides led to the identification of (CH3)2CHCO-His-Trp-Ala-Val-D-Ala-His-Leu-NHCH3 (ICI 216140) which reduced bombesin-stimulated rat pancreatic amylase secretion to basal levels when administered subcutaneously at 2.0 mg per kg.  相似文献   
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This paper describes effects of a sublethal (1.2 mg 1–1) organophosphate, malathion, on the ovary of an air breathing catfish, Heteropneustes fossilis. The study focuses on microscopic changes that occur on ovigerous lamellae, oocytes at different stages of development and the nucleus of the immature oocyte. Also, change in estrogen levels in blood serum is investigated. Clumping of cytoplasm appears after 24 h of exposure to malathion. Clumping intensified after 48 h. Degeneration in the follicular cells was also observed. After 72 h exposure the number of nucleoli increased, nuclear materials shrunk, oocytes became adhered. With 96 h of exposure, nuclear materials of all the oocytes shrunk to a smaller clump. The oocytes fused together, and follicular epithelium became loose and ruptured. A few atretic oocytes were visible. Radioimmunoassay of the estrogen level in blood serum after 72 h of exposure of malathion showed a reduction in the level. This study showed that the histopathological condition of the gonad is reflected in malfunctioning of the endocrine system and hormonal disbalance.  相似文献   
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Sodium chloride-tolerant calli were selected from leaf-derived embryogenic calli of Dactylis glomerata L. on agar solidified medium supplemented with 200 mM NaCl, a concentration lethal to non-selected calli. Growth characteristics, water relations and proline accumulation pattern were compared in selected and non-selected lines. The objective was to gain an understanding of the mechanism(s) of tolerance in the NaCl-tolerant line. Growth in the selected line, as expressed in terms of tolerance index (ratio of fresh wt. on NaCl medium:fresh wt. on NaCl free medium x 100), was greater than that of the non-selected line at all levels of NaCl between 50 and 300 mM. There was no significant difference in proline accumulation in the selected and non-selected lines. Maintenance of turgor by osmotic adjustment was observed in the non-selected line despite decreased growth. In contrast, the selected line lost either the need or the ability to adjust osmotically. There was little or no increase in symplastic osmolality in the selected line when exposed to NaCl. Presumably, selection was made for a salt-excluding tissue that has lost the ability to accumulate solutes and adjust turgor with NaCl stress.  相似文献   
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Investigation of the North American species Psilostrophe villosa afforded, in addition to known compounds, five new sesquiterpene lactones, which all turn out to be modified pseudoguaianolides, most of them closely related to hymenolide. However, one of the lactones is a new type of nor-pseudoguaianolide. Furthermore a new monoacetylated borneol-β-D-glucoside is present. The chemotaxonomic situation is discussed briefly.  相似文献   
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Summary The hyomandibula is an important element of the head and has been influenced in its structural features by different functions. It is roughly T-shaped with vertical and horizontal ridges. In fish, such asMacropodus opercularis, the deep curve at the antero-dorsal end of this ridge may be correlated with the concentrated force applied by the adductor mandibulae muscles. InMacropodus opercularis, the hyomandibula is shorter and broader than that ofAnabas testudineus andCtenopoma acutirostre. In the latter two genera, almost the entire anterior surface of the vertical ridge is uniformly curved, which may be explained by the distributive force applied by the adductor muscles perpendicularly. InMacropodus, the hyomandibulo-interhyal articulation is not straight along the axis of the interhyal as inCtenopoma, but the interhyal makes an angle of 45 to the hyomandibula. This difference might be functional as well as due to the oblique orientation of the hyomandibula. InCtenopoma, the articulating facet of the symplectic is located slightly below the interhyal articulating facet. This might be caused by the location of the hyomandibulo-interhyal articulation. The hyomandibulo-interhyal articulation also helps in the depression of the lower jaw when the latter is depressed by the hyoid bar. Thus, a structural analysis of the hyomandibula and its relationships with functions depict the interrelation between form and function.  相似文献   
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