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Bamboo stumps as mosquito larval habitats in Darjeeling Himalayas, India： A spatial scale analysis

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Insect Science 2008年第3期15卷 245-249页

作者： Gautam Aditya Rakesh Tamang Dipendra Sharma Francis Subba Goutam K. Saha Department of zoology Darjeeling Govemment College Darjeeling 734101 Department of zoology University of Calcutta 35 Ballygunge Circular Road Kolkata 700019 Department of zoology the University of Burdwan Golapbag Burdwan 713104 India

Bamboo stumps can be a congenial breeding habitat of the mosquitoes. In view of this, a preliminary assessment of the dipteran immatures inhabiting the stumps of bamboo groves in the Darjeeling Himalayas was carded out at a spatial scale. Of the 104 stumps of Dendrocalamus hamiltoni surveyed, 70 were found to host immatures of three dipteran species, the mosquitoes Aedes aegypti and Culex quinquefasciatus and the midges Chironomus sp. in varying densities. Though the stumps varied in diameter, in each stump on average 12. 1 immatures were found. The abundance of the immatures was positively correlated with the diameter of the stumps （r = ＋0.382; P 〈 0.001） but negatively with the pH of the water present in the stumps （r = -0.336; P 〈 0.01）. The coefficient of association was found to be ＋8.4 for the Ae. aegypti and Chironomus immatures, while in the rest of the species pair the association seemed to be independent. Thus it can be concluded that the stumps in the bamboo groves of Darjeeling Himalayas provides a favourable habitat for the mosquito and chironomid immatures.

关键词： Aedes aegypti bamboo stumps Chironomus sp. Culex quinquefasciatus,Darjeeling interspecific association phytotelmata

Histochemical pattern of gastrocnemius muscle in fluoride toxicity syndrome

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Asian Pacific Journal of Tropical Medicine 2010年第2期3卷 136-140页

作者： Shashi A Bhushan B Bhardwaj M Department of zoology Punjabi University

Objective:To evaluate the effect of sodium fluoride(NaF) on cytochemical distribution of proteins,DNA,and RNA in the gastrocnemius muscle of rat in experimental ***: Young Sprague Dawley albino rats were administered with NaF at 30,45,and 75 mg/kg bw/ day subcutaneously for 15 and 30 days,*** control animals were given the vehicle(1cc deionized double distilled water/kg bw/day).Results:In the first phase of 15 days experimentation,the gastrocnemius muscle of rats intoxicated with NaF at 30,45,and 75 mg /kg bw/ day showed decline in proteins including a amino acids as compared to control. In the second phase of 30 days experimentation,the muscle fibers of rat showed elevation in sarcolemmal and sarcoplasmic proteins in 30 mg NaF dose group,and angulated fibers exhibited increase in sarcolemmal proteins in 45 mg NaF *** marginal regions of angular and rim fibers showed deeply stained rings of sarcoplasmic proteins whereas the split fibers were faindy stained in rats treated with NaF at 75 mg/kg bw/day for 30 *** rats treated with NaF at 30 mg/kg bw/day for 15 days,the hypertrophied peripheral muscle fibers contained more DNA,however the atrophied fibers had more *** 45 mg NaF group,RNA was located in sarcolemmal regions,while DNA content decreased as compared to *** 75 mg NaF group,the muscle fibers had dark and light staining regions of DNA and *** the 30 days of experimentation,the DNA level decreased whereas RNA content increased in the gastrocnemius muscle fibers of the rat treated with NaF at 30 mg/kg bw/*** treatment group with NaF at 45 mg/kg bw/day,the RNA content slighdy declined in comparison to control,in all treatments for 15 days as well as in treatment group with NaF at 30 mg/kg bw/day for 30 days whereas the amount of DNA slightly increased as compared to treatment group with NaF at 75 mg/kg bw/day for 15 *** highest dose group revealed elevated amount of RNA whereas DNA content remained stable.C

关键词： Albino rats DNA Gastrocnemius muscle Proteins RNA Sodium fluoride

Pathological evaluation of pancreatic exocrine glands in experimental fluorosis

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Asian Pacific Journal of Tropical Medicine 2010年第1期3卷 36-40页

作者： Shashi Aggarwal Sharma N Bhardwaj M Department of zoology Punjabi University

Objective:To monitor the pathological alterations in pancreas of rat during experimental fluorosis. Methods:Sixty Sprague Dawley albino rats of both sexes were divided into 12 experimental groups and one control *** rats of control group were administered subcutaneously double distilled water 1 mL/kg bw *** experimental groups were injected with 30,45,and 75 mg NaF/kg bw/*** experimental period was divided into 4 phases at interval of 15,22,30,and 36 *** were sacrificed from each group at the end of 16,23,31,and 37 ***: The following changes were observed in this study:(1) Pathological examination of pancreas after 15 days of fluoride treatment revealed:hypertrophy of acini,leucocytes infilteration and pycnouc nuclei due to necrosis of acini in group 1;uremic alterations,invulsion and infoldings of reticular layer of islets of Langerhans in group 2;and a decrease in number of acini and interlobular connective tissues resulted in an increase in intercellular spaces in pancreas of rats in group 3.(2)Hyalinization and hypertrophy in the lobules of acini and hyperplasia and hypertrophy in intercalated duct with mucinous secretion in pancreas of rat of group 4;squamous metaplasia of pancreatic duct,adenoma of pancreas,hemorrhagic necrosis in group 5;and hyperplasia of acini and reduction in number of pancreatic islets in group 6.(3) Disorganization and atrophy of pancreatic lobules and presence of vacuoles in a group of six were visible in pancreas of rats in group 7;acute pancreatic and lamellated inflammatory cells in test rats of group 8;and islet adenoma and decrease in number of islets cells,and exudation in acini were noticed in experimental rats of group 9.(4) In the last phase of experimentation,atrophic alterations in pancreatic acini,invulsions,and necrosis was prominent in group 10,deep inflammation and proliferation of connective tissue of pancreas in experimental group 11,and periodical fibrosis, hyperplasia of acini,degener

关键词： Acini Albino rat Exocrine gland Experimental fluorosis Pancreas Sodium fluoride

Degenerate slave-makers,but nevertheless slave-makers?Host worker relatedness in the ant Myrmoxenus kraussei

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Integrative zoology 2015年第2期10卷 182-185页

作者： Masaki SUEFUJI Jürgen HEINZE zoology/Evolutionary Biology University of RegensburgGermany

Socially parasitic ants of the formicoxenine genus Myrmoxenus exhibit considerable diversity in colony structure and life *** some species are active slave-makers with many workers and others are workerless‘murder-parasites,’Myrmoxenus kraussei is considered as a‘degenerate slave-maker’because of its very low worker ***,we document that Temnothorax recedens host workers in single colonies of *** from Lago di Garda,Italy,exhibit significantly more genetic diversity than workers in unparasitized *** raises the possibility that,despite its low worker numbers,*** may actively engage in slave raids in nature.

关键词： dulosis nestmate relatedness Myrmoxenus social parasitism slave-making

Understand comprehensive perspectives of evolution

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Integrative zoology 2023年第2期18卷 206-207页

作者： Wenhua XIONG Integrative zoology Institute of zoology Chinese Academy of SciencesChina Office of the International Society of Zoological Sciences

Evolution is the key to understanding the theories of *** in biology makes sense except in the light of evolution(Dobzhansky 1973).Beyond the traditional method of morphology,we are aware of the possibilities of new scientific discoveries to be cognizant of the development of anatomy,paleontology,computational biology,phylogenetic analysis,and molecular means.

关键词： evolution anatomy Beyond

Long-term administration of large doses of paracetamol impairs the reproductive competence of male rats

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Asian Journal of Andrology 2000年第4期2卷 247-255页

作者： W.D.Ratnasooriya J.R.A.C.Jayakody Department of zoology University of Colombo Colombo 3 Sri Lanka.Department of Zoology University of Colombo Colombo 3 Sri Lanka.

Aim: To evaluate the antireproductive effect of paracetamol in male rats. Methods: Male rats were orally adminis-tered daily with 500 mg/kg or 1000 mg/kg of paracetamol for 30 consecutive days. Their sexual behaviour and fertilitywere evaluated using receptive females. Results: At 2 h after treratment, sexual behaviour was not inhibited but onday 30 both doses of paracetamol caused marked impairment of libido (assessed by % mounting, % intromission and% ejaculation), sexual vigour (number of mounts and intromissions and copulatory efficiency) or sexual performance(intercopulatory interval). In mating experiments, the fertility (in terms of quantal pregnancy, fertility index, implan-tation index and number of implants) was significantly reduced. All these effects were reversible. The antireproductiveeffect was not due to a general toxicity but due to an increase in pre-implantation losses resulting from oligozoospermia,impairments of normal and hyper-activated sperm motility, and reduction in the fertilizing potential of ***: Long-term use of high doses of paracetamol may be detrimental to male reproductive competence.( Asian J Andro12000 Dec; 2: 247-255 )

关键词： paracetamol fertility sexual behaviour oligozoospermia pre-implantation loss capacitation sperm motility

The saproxylic beetle assemblage associated with different host trees in Southwest China

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Insect Science 2008年第3期15卷 251-261页

作者： Jie Wu Xiao-Dong Yu Hong-Zhang Zhou Institute of zoology Chinese Academy of Sciences Beijing China

Dead wood is a habitat for many insects and other small animals, some of which may be rare or endangered and in need of effective protection. In this paper, saproxylic beetle assemblages associated with different host trees in the subtropical forests in southwestern China were investigated. A total of 277 species （1 439 specimens） in 36 beetle families were collected from 117 dead wood samples, of which 101 samples were identified and respectively belonged to 12 tree genera. The number of saproxylic beetle species varied greatly among logs of different tree genera, with the highest diversity on logs of Juglans. Generally, broad-leaved trees had a higher richness and abundance of saproxylic species than coniferous trees. Cluster analysis revealed that assemblages from broad-leaved tree genera were generally similar （except for Betula） and assemblages from coniferous trees formed another distinct cluster. The subsequent indicator analysis proposed that there are different characteristic species for different cluster groups of host tree genera. In our study, log diameter has no positive influence on beetle species density. Conversely, comparisons of individual-based rarefaction curves suggested that beetle species richness was highest in the small diameter class both in coniferous and broad-leaved tree genera. With increased wood decay, proportion of habitat specialists （saproxylic beetles living on one tree genus） decreased, whereas proportion of habitat generalists （living on more than three tree genera） increased. The beetle species density was found to be higher in early stages, and decreased in later stages as well. A negative influence of altitude on saproxylic beetle species richness and abundance was detected. It was indicated that different tree genera and altitudes possibly display cross effects in modulating the altitudinal distribution and host preference of the beetles.

关键词： China host trees Saproxylic beetle subtropical forest

Differential Genotoxicity of the Crude Leaf Extract of a Medicinal Plant, Casearia tomentosa

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Biomedical and Environmental Sciences 2000年第1期13卷 12-18页

作者： K.S.AWASTHY O.P.CHAURASIA S.P.SINHA P.K.KHAN Department of zoology Bhagalpur UniversityBhagalpur 812007India

The genotoxic potentiality of the crude leaf extract of Casearia tomentosa, a medicinal preparation, has been evaluated in Swiss albino mice. The extract significantly induced the division_disruptive chromosomal changes in bone marrow cells as well as in primary spermatocytes; the latter also exhibited marked increase in synaptic disruptions. A significant decrease in sperm count was noted. The incidence of structural damages in chromosomes, however, remained within the range of control level frequency. This herbal preparation, therefore, appears to be primarily spindle_poisoning in its action, but not clastogenic. The probable mechanism of this differential genotoxicity is discussed.

关键词： Animals Bone Marrow Cells Male Mice Mitotic Spindle Apparatus Mutagenicity Tests Plant Extracts Plants, Medicinal Sperm Count Spermatocytes

Histologic changes in the mouse testis after bilateral vasectomy

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Asian Journal of Andrology 2000年第2期2卷 115-120页

作者： Shio Kumar Singh Suman Chakravarty Department of zoology Banaras Hindu University Varanasi 221 005 IndiaDepartment of Zoology Banaras Hindu University Varanasi 221 005 India

Aim: To study the effect of vaseetomy on histological appearance of the testis. Methods: Parkes strain mice wereused as the animal model; they were bilaterally vasectomized (Vx) or sham-operated (So) and killed at intervals of 4,6, 9, and 12 months after the operation. Testes were excised from 5 Vx and 5 So mice at each interval and processed for histological examination. Results: Testes of So mice showed normal histological features. By contrast, marked al-terations were observed in the seminiferou tubules in testes of Vx mice, except in those killed 4 months after the opera-tion. The seminiferous epithelium in the tubules was only 2-3 layers thick and showed much depletion of germ cells;in severe cases, the epithelium consisted of only a thin layer of Sertoli cells, spermatogonia and a few *** of germ cells, occurrence of multinucleated giant cells and vacuolated appearance of the epithelium were ofcommon features in the tubules. Furthermore, lumen of the rete testis in Vx mice was greatly dilated and showed accu-mulation of sermatozoa with immature germ cells; in mice vasectomized for 6-12 months, several macrophages in-gesting spermatozoa were ofte observed in the lumen of the rete testis. Spermatic granuloma was also somettimes no-ticed in corpus or in cauda regions of the epididymis in mice vasectomized for 6-12 months. Conclusion: We sug-gest that consequences of vasectomy should be thoroughly understood in order to make this method rather more popularas a reversible method of male contraception.

关键词： vasectomy testis mouse contraception