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1.
In the present study the whole sample of 772 desert gerbils was collected from the semi-arid areas in and around Jaipur (Rajasthan, India). The male exhibits active spermatogenesis and well maintained accessory reproductive organs at any time of the year. Reproductive organs of the male gerbil are briefly described. The vaginal and urinary openings are independent in the gerbil. There are four pairs of mammae. Follicular development takes place cyclically. Maximum atresia of follicles is noticed during metoestrus. A well developed Graafian follicle measures 590 μ across its widest diameter. The average diameter of the ovum is 65 μ. At the time of ovulation formation of stigma occurs which gives way to the ovum. The corpus luteum is formed from the remaining granulosa cells of the ovulated follicle. Fully formed corpus luteum of the cycle (during dioestrus) measures 740 μ. Maximum development of the corpus luteum is seen during late pregnancy (22–25 days) when it measures 1250 μ. During pregnancy large Graafian follicles are absent. After parturition the ovary shows corpora lutea of lactation. Histological changes in the uterus and vagina during the oestrous cycle of the gerbil are described. There is less proestrus distension of the uterus as compared with the rat. During oestrus the uterine endometrium hypertrophies and there are some degenerative changes in the epithelial lining. The changes in the vaginal epithelium are clear cut and are correlated with the ovarian activity. During proestrus proliferation of the epithelium occurs and at ‘heat period’ or oestrus the epithelium shows formation of the stratum corneum and the shedding of cornified cells. In the dioestrus the vaginal epithelium is heavily infiltrated by leucocytes. There are three peaks in the incidence of pregnancy rate, i.e., February to April, July, and September to November. Pregnancy rate is lowest during summer (May and June) and winter (December and January). Average monthly litter size shows almost similar changes. The average length of gestation period is 30 days. There is post-partum heat in this animal. Formation of a vaginal plug is noticed following copulation. Litter size varies from 2–7. The average body weight of the new born young is 3.5 and 3.4 gm respectively for the male and the female. Weaning of the young is observed after about 20 days. Descent of the testes into the scrotal sacs occurs around day 28. Vagina opens after about 75 days.  相似文献   
2.
Solarization of soil was found beneficial for plant growth in cowpea under field conditions. Root nodulation, infection by mycorrhizal fungi and yield were higher in plants grown in solarized soil. These increases were to the extent of 104.7, 20.0 and 23.7 per cent respectively when compared to control treatment without solarization.  相似文献   
3.
The responses of the field mouse Mus booduga to shifts in schedules of LD cycles were monitored and the results were interpreted with the help of a PRC constructed for the same species. The results reveal that, M. booduga reentrained faster with a lesser number of transients after delay shifts than advance shifts, thus exhibiting “asymmetry effect.” A positive correlation was observed between the number of transients and the number of hours of shift. In most of the shifts, the sign of the transients (negative for delaying transients and positive for advancing transients) coincided with the direction of the shift. Interestingly, 11 and 12 h of advance shifting resulted in delaying transients. An 11-h advance shift can also be interpreted as a 13-h delay. Reentrainment through delaying transients is faster as compared to reentrainment through advancing transients. Thus, this animal might have taken a “shorter route,” as proved by the fact that an 11-h advance shift has evoked delaying transients. But a 13-h advance shift evoked only advancing transients. This prompts us to speculate that there may be a “phase jump” in M. booduga. Further, irrespective of whether L or D has been doubled in a 12-h shift, both evoked only delaying transients.  相似文献   
4.
The species of flies breeding in bovine manure, their parasites and predators as well as other associated arthropods in 3 localities in and near Bangalore are recoreded. The flies areMusca domestica L.,Musca pattoni Austen,Stomoxys calcitrans L.,Physiphora aenea F.,Physiphora demandata F.,Sargus metallinus F.,Sepsis thoracica R.-D.,Sepsis nitens Wiedemann,Sphaerocera scabricula Hal, andLeptocera (Coproica) hirtula Rondani. Four species of hymenopterous pupal parasites of these flies have been obtained:Spalangia cameroni Perkins from pupae ofM. domestica, M. pattoni, S. calcitrans, P. aenea andP. demandata; Spalangia endius Walker from pupae ofM. domestica, M. pattoni andS. calcitrans; Spalangia nigroaenea Curtis from pupae ofM. domestica andS. calcitrans; andDirhinus trichiophthalmus Masi from pupae ofSargus metallinus F. Percentage parasitism of fly puparia in field samples was noted. Four species ofHister andAleochara puberula Klug feeding on various immature stages ofM. domestica, 2 species of scarabaeid beetles, 2 species of ants and a pseudoscorpion were also found in the manure. The importance of biotic regulatory factors in the control of flies is discussed.
Résumé Dans 3 localités de Bangalore ou proches de cette ville, on a inventorié les espèces de mouches vivant dans le fumier de vache, leurs parasites et prédateurs ainsi que d'autres arthropodes associés. Les mouches récoltées sont:Musca domestica L.,Musca pattoni Austen,Stomoxys calcitrans L.,Physiphora aenea F.,Physiphora demandata F.,Sargus metallinus F.,Sepsis thoracica R-D.,Sepsis nitens Wiedemann,Sphaerocera scabricula Hal. etLeptocera (Coproica) hirtula Rondani. Quatre espèces d'hyménoptères parasites des pupes ont été obtenues de ces mouches:Spalangia cameroni Perkins deM. domestica, M. pattoni, S. calcitrans, P. aenea etP. demandata: Spalangia endius Walker deM. domestica, M. pattoni etS. calcitrans, P. aenea etP. demandata; Spalangia endius Walker trans; etDirhinus trichiophthalmus Masi deSargus metallinus F. On a noté le taux de parasitisme des nymphes dans les conditions naturelles. Quatre espèces deHister etAleochara puberula Klug s'attaquant aux divers stades non imaginaux deM. domestica, 2 espèces de scarabeides, 2 espèces de fourmis et un pseudoscorpion ont été également trouvés dans le fumier. L'importance de ces facteurs biotiques dans la régulation des populations de mouches est discutée.


Paper presented at the seminar on utilization of farm wastes for rural industrial growth, National Dairy Research Institute, Bangalore, 31 st December, 1975.

This paper is published with the permission of the Director-General, Indian Council of Medical Research, New Delhi  相似文献   
5.
The interaction of the delta-opioid receptor selective peptides, cyclic [D-Pen2, D-Pen5]-enkephalin [DPDPE] and its acyclic analog, DPDPE(SH)2, with neutral phospholipid bilayer membranes was examined by permeability and calorimetry measurements. The permeabilities were accomplished by entrapping either peptide inside of unilamellar liposomes (composed of a mixture of a molar ratio 65:25:10 phosphatidylcholine/phosphatidylethanolamine/cholesterol) then monitoring the peptide efflux through the bilayer. The initial permeability of DPDPE (first 12 h) averaged over four experiments was (0.91 +/- 0.47).10(-12) cm s-1. In contrast the average permeability of the acylic DPDPE(SH)2 was (4.26 +/- 0.23).10(-12) cm s-1. The effect of these peptides on the phase transition, Tm, of 1,2-dipalmitoylphosphatidylcholine (DPPC) bilayers was examined by high sensitivity differential scanning calorimetry. The Tm, the calorimetric enthalpy, and the van 't Hoff enthalpy of DPPC were not significantly altered by the presence of DPDPE, whereas the calorimetric data for DPPC with DPDPE(SH)2 showed a small, yet significant, increase (0.2 degrees C) in the Tm with a 30% decrease in the cooperative unit. Both the permeability and calorimetry data reveal a stronger peptide-membrane interaction in the case of the more flexible acyclic peptide.  相似文献   
6.
7.
Hybridization between different species of parasites is increasingly being recognised as a major public and veterinary health concern at the interface of infectious diseases biology, evolution, epidemiology and ultimately control. Recent research has revealed that viable hybrids and introgressed lineages between Schistosoma spp. are prevalent across Africa and beyond, including those with zoonotic potential. However, it remains unclear whether these hybrid lineages represent recent hybridization events, suggesting hybridization is ongoing, and/or whether they represent introgressed lineages derived from ancient hybridization events. In human schistosomiasis, investigation is hampered by the inaccessibility of adult-stage worms due to their intravascular location, an issue which can be circumvented by post-mortem of livestock at abattoirs for Schistosoma spp. of known zoonotic potential. To characterise the composition of naturally-occurring schistosome hybrids, we performed whole-genome sequencing of 21 natural livestock infective schistosome isolates. To facilitate this, we also assembled a de novo chromosomal-scale draft assembly of Schistosoma curassoni. Genomic analyses identified isolates of S. bovis, S. curassoni and hybrids between the two species, all of which were early generation hybrids with multiple generations found within the same host. These results show that hybridization is an ongoing process within natural populations with the potential to further challenge elimination efforts against schistosomiasis.  相似文献   
8.
9.
ABCG1 is an ABC half-transporter that exports cholesterol from cells to HDL. This study set out to investigate differences in posttranslational processing of two human ABCG1 protein isoforms, termed ABCG1(+12) and ABCG1(- 12), that differ by the presence or absence of a 12 amino acid peptide. ABCG1(+12) is expressed in human cells and tissues, but not in mice. We identified two protein kinase A (PKA) consensus sites in ABCG1(+12), absent from ABCG1(- 12). Inhibition of PKA with either of two structurally unrelated inhibitors resulted in a dose-dependent increase in cholesterol export from cells expressing ABCG1(+12), whereas ABCG1(- 12)-expressing cells were unaffected. This was associated with stabilization of the ABCG1(+12) protein, and ABCG1(+12)-S389 was necessary to mediate these effects. Mutation of this serine to aspartic acid, simulating a constitutively phosphorylated state, resulted in accelerated degradation of ABCG1(+12) and reduced cholesterol export. Engineering an equivalent PKA site into ABCG1(- 12) rendered this isoform responsive to PKA inhibition, confirming the relevance of this sequence. Together, these results demonstrate an additional level of complexity to the posttranslational control of this human ABCG1 isoform that is absent from ABCG1(- 12) and the murine ABCG1 homolog.  相似文献   
10.
A strain of Bacillus amyloliquefaciens (VCRC B483) exhibiting mosquito pupicidal, keratinase and antimicrobial activities was isolated from mangrove forest ecosystem of Andaman and Nicobar Islands. Molecular characterization of the strain showed the presence of lipopeptide encoding bmyC gene. Phylogenetic tree based on protein sequence of this gene exhibited homology with mycosubtilin synthetase of Bacilus atropheus and Iturin synthetase of Bacillus subtilis and B. amyloliquefaciens. This is the first report on the evolutionary conservation of amino acids concerned with the function and structure of bmyC protein of B. amyloliquefaciens. The presence of valine at the 1197th position in our strain was found to be unique and different from the existing strains of B. subtilis and B. amyloliquefaciens. Molecular modelling studies revealed significant changes in the structure of epimerization domain of the bmyC protein with A1197V variation. Crude metabolite of this strain exhibited antifungal activity against Fusarium sp. and Carvularia sp.  相似文献   
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