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1.
八种沙鼠亚科和田鼠亚科啮齿动物阴茎的比较研究   总被引:5,自引:2,他引:3  
本文对我国仓鼠科沙鼠亚科和田鼠亚科8种啮齿动物的阴茎进行了比较解剖学研究。分析了两亚科的沙鼠属(Meriones)、大沙鼠属(Rhombomys)、田鼠属(Microtus)和绒鼠属(Eothenomys)4个属之间以及同属的种间异同。结果证明阴茎头(包括阴茎骨和软体结构)的形态结构具有属和种的稳定性和特异性,可以作为分类学研究的重要依据。  相似文献   

2.
M. Alonso 《Hydrobiologia》1985,128(3):217-228
A very particular form of Daphnia (Ctenodaphnia), adapted to life in epicontinental hyperhaline waters of Mediterranean arid regions had long been confused with Daphnia (Ctenodaphnia) dolichocephala Sars, 1895. In this paper the morphological and ecological differences between the two taxa are pointed out and comparison is made with another closely related Rumanian form (Daphnia cf. mediterranea) and with the related Spanish species (D. atkinsoni and D. chevreuxi). The Daphnia of saline environments is described here as Daphnia (Ctenodaphnia) mediterranea. The most important differential characters of this new species are: 1) the short and widely rounded rostrum; 2) dorsal ridge of the female extends to the anteriormost part of the head; 3) elliptical ephippium with a ride anterior margin; convex shape and separate from the dorsal ridge; 4) males possessing a very long antennule base that reaches the distal limit of the head.  相似文献   

3.
Summary The topography of oxytocin (OT)- and vasopressin (VP)-containing axons of the hypothalamo-neurohypophyseal system was studied in the neurohypophysis of the Djungarian hamster (Phodopus sungorus) by means of immunohistochemistry. Compared with other mammalian species, the neurohypophysis of Phodopus shows some peculiarities. Accumulations of OT-immunoreactivity around the distal vessels of the primary portal plexus can be observed in the distal median eminence and neural stem. This staining pattern indicates that OT is secreted into portal blood. In the neural lobe, OT- and VP-immunopositive fibers terminate in different areas. The vast majority of the OT-containing axons is distributed in the dorsal part of the neural lobe. In contrast, VP-containing axons are mainly found in the centre of the neural lobe up to the pars intermedia.  相似文献   

4.
Morphological differences among groups of the 24 trunk limbs of Caenestheriella gifuensis (Ishikawa, 1895) and differences between males and females are described and illustrated. A setose attenuate lobe located proximally near enditic lobe 1 and a discoid lobe covered with small setae proximal to enditic lobe 1 are newly described. The five ventral enditic lobes, endopod, exopod, and dorsal exite of traditional spinicaudatan morphology are redescribed. Trunk limbs 1–4 of females bear a palp on enditic lobe 5 and trunk limbs 1–15 of males bear a similar palp. A second, articulating palp is associated with the base of the endopod of trunk limbs 1–2 of males. The proximal part of trunk limbs 19–24, bearing enditic lobe 1, articulates by an arthrodial membrane with the remainder of the limb, and the exite is distal to this arthrodial membrane. Development of trunk limbs, ascertained through an examination of early juvenile instars of Leptestheria kawachiensis Uéno, 1927, includes an asetose limb followed in time by a series of setose limbs that increase in morphological complexity with age. The number of lobes on the asetose limb varies from seven (corresponding to five enditic lobes, an endopod, and an exopod) on anterior limbs to five on trunk limb 24, which lacks the lobes corresponding to enditic lobe 4 and the endopod; these two structures are added later to setose limbs. The attenuate lobe, the discoid lobe, the exite of all trunk limbs, and the palps of the anterior trunk limbs are added to the setose limbs. Development of anterior limbs is accelerated relative to that of posterior limbs, and development of the more posterior limbs is truncated relative to that of limbs immediately anterior to them. Enditic lobe 4 and the endopod of limbs like trunk limb 24 develop from, or are patterned by, enditic lobe 5; the articulating palp of male trunk limbs 1–2 also may be added in this way. A comparison of these observations with development of the copepod maxilliped suggests that the spinicaudatan trunk limb is composed of a praecoxa with three lobes, a coxa and a basis each with one lobe, and an endopod of three segments in females and four in males. This is similar to the homology scheme previously proposed by Hansen in 1925. A critique is given of attempts to homologize parts of arthropod limbs based on developmental gene expression patterns. Stenopodal to phyllopodal transformations of maxillipeds in copepods provide a model at least partly applicable to spinicaudatans, and a ‘multibranched’ interpretation of spinicaudatan (and by extension branchiopodan) limb morphology is rejected. There is nothing intrinsic to the structure of the adult trunk limbs suggesting that they are similar to the adult limbs of the ancestral branchiopod or the ancestral crustacean, but early developmental steps of more posterior limbs are good matches for the morphology of an ancestral crustacean biramal limb predicted by a hypothesis of duplication of the proximo‐distal axis. © 2003 The Linnean Society of London, Zoological Journal of the Linnean Society, 2003, 139 , 547–564. No claim to original US government works.  相似文献   

5.
6.
[目的] 研究镇江香醋酿造过程核心功能微生物醋酸杆菌属与乳酸杆菌属菌株之间的相互作用关系。[方法] 本文以分离到的镇江香醋酿造中的核心微生物2株醋酸杆菌和8株孔酸杆菌为研究对象,构建醋酸杆菌和乳酸杆菌共培养发酵体系,比较异位与原位条件下,纯培养及共培养中菌株的生长和代谢(包括还原糖、乙醇和总酸等含量)差异;采用GC-MS检测原位共培养中挥发性物质的变化,分析微生物间的交互作用对镇江香醋主要风味物质形成的潜在影响。[结果] 醋酸杆菌和乳酸杆菌之间的交互作用具有种间特异性和环境特异性,A.pasteurianus G3-2和L.helveticus M3-1、L.plantarum M10-1、L.pontis M17-5及L.reuteri GE7-1在异位及原位模拟共培养中整体的生长和代谢优于纯培养;A.pomorum G15-6和L.paracasei E1-1在异位和原位共培养下还原糖利用率和总酸的产生率都低于纯培养,和L.helveticus M3-1、L.reuteri GE7-1、L.plantarum M10-1、L.fermentum M10-3、L.casei E10-1、L.pontis M17-5、L.hilgardii M3-4共培养在异位和原位模拟中代谢不一致。根据GC-MS分析显示,A.pasteurianus G3-2和L.helveticus M3-1及L.reuteri GE7-1原位模拟共培养时异戊酸、乙酸乙酯、甲酸辛酯等风味物质的含量明显优于纯培养,其中一种重要风味物质2,3-丁二酮只在共培养时被检出,其含量分别达到了9.87 mg/L及14.28 mg/L。[结论] 镇江香醋醋醅中的醋酸杆菌和乳酸杆菌之间的交互作用能够影响菌株生长和主要代谢产物生成,这一研究有助于深入剖析镇江香醋风味形成的酿造机理,为理性调控酿造菌群以改善镇江香醋风味品质奠定了理论基础。  相似文献   

7.
Summary Of 13 ecs mutations, which affect female fertility, as revealed by complementation analysis, 7 are chromosome rearrangements involving the br complementation group. The other six show no cytologically detectable rearrangements and behave as completely or partially noncomplementing ecs alleles. All viable combinations of these 13 mutations were characterized by partial or complete female sterility. Viable heterozygotes carrying any of these mutations and the rearrangements Df(1)sta, T(1,3)sta, Df(1)St490, previously localized distal to the ecs locus, were also sterile. Using deletions and an electrophoretic mobility variant from the Staket strain, a minor chorion gene S70 has been mapped. It had been thought this gene was located in the 2B3-5 region, and corresponded to the ecs locus. However, in the present study, this gene was shown to map in the region removed by Df(1)sta (1E1-2-2B3-4) but outside that removed by Df(1)At127 (1E1-2-2A1-2), i.e. within the 2A1-2-2B3-4 region which is distal to the ecs locus. Rearrangements and point mutations at the ecs locus that result in female sterility had no effect on synthesis of the chorion protein s70. It may therefore be suggested that the chorion protein gene is not functionally associated with the ecs locus and that sterility is caused not by disruptions of the chorion protein gene but by lesions in the ecs gene itself. Thus, an ecs product, which controlls cell sensitivity to ecdysterone is also necessary for female fertility. Data on the locations of lesions affecting female fertility indicate that at least two elements at the ecs locus are essential for this function: a cis-acting distal zone with no effect on viability and a sequence within the essential part of the ecs locus. A defect in either of these zones or their separation by chromosomal rearrangement leads to female sterility.  相似文献   

8.
A. A. Kotov 《Hydrobiologia》1996,341(3):187-196
We investigated the morphology of adult and juvenile stages of females and males of Bosmina longispina Leydig from a North Icelandic population. There are additional setae near the basis of the second antenna and between its branches in adult males, not described in Bosmina, but known from other Anomopoda. New features of female morphology are also found. The development of the first limb and postabdomen of the male is described in detail. In juvenile males of B. longispina (belonging to subgenus Eubosmina), characteristics of morphology, similar to those in adult males of other subgenera are found.Abbreviations af antennal flap - as additional setae of male - bs basis of seta of clasper - bc basis of postabdominal claws - ch clasper hook - cl clasper - cs seta of clasper - cw claws of postabdomen - de distal endite of the first limb - dr dorsal row of denticles on male postabdomen - df dorsal fold of carapace - eh ejector hooks of limb I - ep epipodite - ex exopodite - fp frontal head pore - fs frontal seta - hs hair sensilla - in incision of juvenile male postabdomen - ir interrupted rows of setules on postabdomen - Ip lateral head pore - mp median head pore - mpr maxillar process of limb I - mr main row of denticles on postabdominal claws - pe predistal endite of limb I - pf preantennal fold of valve - pl plate above postabdominal setae - ps postabdominal setae - rs rudimentary setae - sr second row of denticles near basis of claws - vf ventral fold of valve - vr ventral row of denticles on male postabdomen  相似文献   

9.
In vitro culture of adult and juvenile bud explants of Passiflora species   总被引:1,自引:0,他引:1  
Cultivar E23, an F1 hybrid of P. edulis and P. edulis f. flavicarpa is usually propagated by shoot-tip grafting. Various media were tested to evaluate the potential of E23 for in vitro propagation. Adult tissue was difficult to culture and did not respond to media containing low (<10 µM) concentrations of growth regulators. Growth of adult buds on intact stem sections was promoted by 1 week of dark incubation on MS basal medium plus 150 µM 2iP, 200 µM adenine sulphate and 17.1 µM IAA (3 mg l–1), and further developed into shoots on MS medium plus 4.9 µM 2iP (1 mg l–1) and 5.7 µM IAA (1 mg l–1). By contrast, juvenile shoots of E23, and Passiflora species: edulis f. flavicarpa, edulis, alata, caerulea, mollissima, coccinea, herbertiana and suberosa grew rapidly on MS medium plus 10 µM kinetin and 5 µM IAA. Rapid multiplication was achieved on MS plus 20 µM BA, 10 µM kinetin, 5 µM IAA, and roots initiated on MS plus 5 µM IAA.Abbreviations IAA indole-3-acetic acid - 2iP N6-iso pentenyl adenine - BA N6-benzyl adenine  相似文献   

10.
《Journal of bryology》2013,35(2):126-132
Abstract

Two new species of Lejeunea Lib., L. kashyapii sp. nov. and L. mehrana sp. nov. are described from Sikkim, India. The former is characterized by sub-orbicular leaves; first tooth of leaf lobule, 1–3 cells long 1–2 cells wide at base; reniform underleaves slightly wider than long; monoicous sexuality; 2–3-paired male bracts; obcordate perianth with 4–5 smooth keels (2 lateral, auriculate; 2 ventral; 0–1 dorsal, indistinct). Whereas, the latter is characterized by oblong – ovate leaves; lobule 1/6–1/5 as long as lobe; distant – contiguous underleaves with 1–3 teeth on each lobe; dioicous (?) sexuality; 2–4-paired male bracts and 1–2 male bracteoles present near the base of androecia. A key to the Indian species of the genus are provided.  相似文献   

11.
Tamm-Horsfall glycoprotein (THGP), produced exclusively by renal cells from the thick ascending limb of Henle's loop, is attached by a glycosyl-phosphatidylinositol (GPI)-anchor to the luminal face of the cells. Urinary excretion of THGP (50–100 mg/day) occurs upon proteolytic cleavage of the large ectodomain of the GPI-anchored form. N-Glycans, consisting of a large repertoire of sialylated polyantennary chains and high-mannose structures, account for approximately 30% of the weight of human urinary THGP. We describe: (i) the involvement of urinary THGP high-mannose glycans in defense against infections of the urinary tract, caused by type-1 fimbriated Escherichia coli, which recognize high-mannose structures, (ii) the role of GalNAcβ1-4(NeuAcα2-3)Galβ1-4GlcNAcβ1-3Gal (Sda determinant) carried by human THGP in protecting the distal nephron from colonization of type-S fimbriated E. coli which recognise NeuAcα2-3Gal, (iii) the inhibitory effect of sialylated THGP on crystal aggregation of calcium oxalate and calcium phosphate, thus preventing nephrolithiasis. Finally, we outline the importance of N-glycans in promoting the polymerization of THGP, a process resulting in the formation of homopolymers with an Mr of several million in urine. Since THGP defense against diseases of the urinary tract mainly consists in binding damaging agents, its ability to behave as a multivalent ligand significantly enhances this protective role. Dedicated to Winifred M. Watkins, who died on 3rd October 2003, and who contributed so much to identifying the Sda determinant structure expressed by Tamm-Horsfall glycoprotein.  相似文献   

12.
The Anlage of the Drosophila visual system, called eye field, comprises a domain in the dorso-medial neurectoderm of the embryonic head and is defined by the expression of the early eye gene sine oculis (so). Beside the eye and optic lobe, the eye field gives rise to several neuroblasts that contribute their lineages to the central brain. Since so expression is only very short lived, the later development of these neuroblasts has so far been elusive. Using the P-element replacement technique [Genetics, 151 (1999) 1093] we generated a so-Gal4 line driving the reporter gene LacZ that perdures in the eye field derived cells throughout embryogenesis and into the larval period. This allowed us to reconstruct the morphogenetic movements of the eye field derived lineages, as well as the projection pattern of their neurons. The eye field produces a dorsal (Pc1/2) and a ventral (Pp3) group of three to four neuroblasts each. In addition, the target neurons of the larval eye, the optic lobe pioneers (OLPs) are derived from the eye field. The embryonically born (primary) neurons of the Pp3 lineages spread out at the inner surface of the optic lobe. Together with the OLPs, their axons project to the dorsal neuropile of the protocerebrum. Pp3 neuroblasts reassume expression of so-Gal4 in the larval period and produce secondary neurons whose axonal projection coincides with the pattern formed by the primary Pp3 neurons. Several other small clusters of neurons that originate from outside the eye field, but have axonal connections to the dorsal protocerebrum, also express so and are labeled by so-Gal4 driven LacZ. We discuss the dynamic pattern of the so-positive lineages as a tool to reconstruct the morphogenesis of the larval brain.  相似文献   

13.
The genus Mariambera is erected based on the males of M. amazonica n. sp. from Amazonas and M. mariae n. sp. from Minas Gerais. The new genus is easily recognized by the distinctive anal point which has a rounded dorsal lobe with microtrichia and a triangular ventral lobe with very strong, marginal setae, in combination with bare eyes and wing membrane, squama with setae, antenna without strong apical seta, and apparently few, short, very weak, hair-like acrostichals in anterior 1/3 of scutum.  相似文献   

14.
The effects of a range of plant growth regulators on callus production in various Ephedra species were examined. Species examined were E. andina, E. distachya, E. equisitina, E. fragilis var, camplyopoda, E. gerardiana, E. intermedia, E. major ssp procera, E. minima and E. saxatilis. All species produced callus on modified MS medium supplemented with 0.25 M kinetin and 5.0 M 2,4-dichlorophenoxyacetic acid or 1-naphthaleneacetic acid. Neither indole-3-acetic acid nor 3-indolebutyric acid induced significant callus formation but the latter maintained growth of established callus cultures in several species. Suspension cultures of several species were established in MS medium supplemented with 0.25 M kinetin and 5.0 M 2,4-dichlorophenoxyacetic acid or 1-naphthaleneacetic acid. Sustained fresh weight doubling times of 70±7h were recorded for cell suspension cultures of E. andina grown in a semi-continous air-lift bubble bioreactor and a minimum doubling time of 56 h was recorded for E. andina in batch culture. It also proved possible to immobilise E. andina batch cultures in sodium alginate beads.Neither parent plants or in vitro cultures of E. distachya, E. fragilis or E. saxatilis produced alkaloids. Trace quantities of 1-ephedrine and trace-0.14% dwt d-pseudoephedrine were produced by in vitro cultures of other species. The ability to produce alkaloid diminished to zero with successive subcultures.Abbreviations Eph 1-ephedrine - Peph d-pseudoephedrine - RGR relative growth rate - KIN kinetin - 2,4-d 2,4-dichlorophenoxyacetic acid - NAA 1-naphthaleneacetic acid - IBA 3-in-dolebutyric acid - IAA indole-3-acetic acid  相似文献   

15.
Pyrazole and propenone quinoxaline derivatives were tested against intracellular forms of Leishmania peruviana and Trypanosoma cruzi. Both series were tested for toxicity against proliferative and non-proliferative cells. The pyrazole quinoxaline series was quite inactive against T. cruzi; however, the compound 2,6-dimethyl-3-f-quinoxaline 1,4-dioxide was found to inhibit 50% of Leishmania growth at 8.9 μM, with no impact against proliferative kidney cells and with low toxicity against THP-1 cells and murine macrophages. The compounds belonging to the propenone quinoxaline series were moderately active against T. cruzi. Among these compounds, two were particularly interesting, (2E)-1-(7-fluoro-3-methyl-quinoxalin-2-yl)-3-(3,4,5-trimethoxy-phenyl)-propenone and (2E)-3-(3,4,5-trimethoxy-phenyl)-1-(3,6,7-trimethyl-quinoxalin-2-yl)-propenone. The former possessed selective activity against proliferative cells (cancer and parasites) and was inactive against murine peritoneal macrophages; the latter was active against Leishmania and inactive against the other tested cells. Furthermore, insilico studies showed that both series respected Lipinski’s rules and that they confirmed a linear correlation between trypanocidal activities and LogP. Docking studies revealed that compounds of the second series could interact with the poly (ADP-ribose) polymerase protein of Trypanosoma cruzi.  相似文献   

16.
Summary Histological staining of wild-type and sevenless transgenic Drosophila melanogaster bearing Rh3-lacZ fusion genes permits the selective visualization of polarization-sensitive R7 and R8 photoreceptor cells located along the dorsal anterior eye margin. Diffusion of -galactosidase throughout these cells reveals that they project long axons to the two most peripheral synaptic target rows of the dorsal posterior medulla, defining a specialized marginal zone of this optic lobe. Comparison of the staining patterns of marginal and nonmarginal Rh3-lacZ-expressing photoreceptor cells in the same histological preparations suggests that the marginal cells possess morphologically specialized axons and synaptic terminals. These findings are discussed with reference to the neuroanatomy of the corresponding dorsal marginal eye and optic lobe regions of the larger dipterans Musca and Calliphora, and in relation to the ability of Drosophila to orient to polarized light.  相似文献   

17.
Screenhouse studies were conducted to investigate the effects of Fusarium oxysporum f. sp. glycines and Sclerotium rolfsii on the pathogenicity of Meloidogyne incognita race 2 on soybean and the influence of the nematode on wilt incidence and growth of soybean. The interaction of each fungus with the nematode resulted in reduced shoot and root growth. Final nematode population was also reduced with concomitant inoculation of nematode and fungus or inoculation of fungus before nematode. While M. incognita suppressed wilt incidence in two nematode-susceptible cultivars of soybean (TGX 1485-2D and TGX 1440-IE), it had limited effect on wilt incidence in the nematode resistant cultivar of soybean (TGX 1448-2E). When F. oxysporumwas inoculated with the nematode, the mean number of nematodes that penetrated soybean roots decreased by 75% in TGX 1448-2E, 68% in TGX 1485-1D and 65% in TGX 1440-1E. Similarly when the soil was treated with S. rolfsii, the number decreased by 78% in TGX 1448-2E, 77% in TGX 1485-1D and 68% in TGX 1440-1E. The nematode did not develop beyond second-stage juvenile in TGX-1448-2E.  相似文献   

18.
中国淡水硅藻新记录——偏肿内丝藻兴凯变种   总被引:1,自引:0,他引:1  
于2016年5月对浙江省仙居国家公园进行藻类多样性调查时,发现了中国淡水硅藻的1个新记录种——偏肿内丝藻兴凯变种[Encyonema ventricosum var.hankensis(Skvortzov) RodionovaPomazkina]。该文采用光镜和扫描电镜对偏肿内丝藻兴凯变种浙江种群的形态特征进行了观察和描述,并将其与该种的其他地理种群及内丝藻属其他相似物种的形态特征进行比较,同时讨论了该物种的生境特征。结果表明:(1)偏肿内丝藻兴凯变种壳面均具明显背腹之分,背缘明显拱起,腹缘轻微波曲;端部呈头状至喙状。(2)偏肿内丝藻兴凯变种浙江地理种群在背部中央区域具一孤点,而其兴凯种群对孤点这一特征未有描述。(3)偏肿内丝藻兴凯变种在俄罗斯的兴凯湖和贝加尔湖等地有分布,该种在中国是首次报道。  相似文献   

19.
The Rf3 gene restores the pollen fertility disturbed by S male sterile cytoplasm. In order to develop molecular markers tightly linked to Rf3, we used amplified fragment length polymorphism (AFLP) technique with near isogenic lines (NILs) and bulk segregant analysis (BSA). A BC1F1 population from a pair of NILs with different Rf3 locus was constructed and 528 primer combinations was screened. A linkage map was constructed around the Rf3 locus, which was mapped on the distal region of chromosome 2 long arm with the help of SSR marker UMC2184. The closest marker E7P6 was 0.9 cM away from Rf3. Marker E3P1, 2.4 cM from Rf3, and E12M7, 1.8 cM from Rf3, were converted into a codominant CAPS and a dominant SCAR marker, and designated as CAPSE3P1 and SCARE12M7, respectively. These markers are useful for marker-assisted selection and map-based cloning of the Rf3 gene.  相似文献   

20.
Alona brandorffi sp. n, related to A. verrucosa Sars, 1901 is described from Boa Vista, Brazil. Parthenogenetic females and males of A. brandorffi were studied. Examination of trunk limbs of A. brandorffi reveals several unusual modifications in structure, unique for the genus, such as very short setae on endites 2 and 3 of limb I, peculiar IDL setae, limb II with scrapers 7–8 with reduced distal part and only six, instead of seven setae in the filter plate, limb IV with only three, instead of four, setae on the inner lobe. The relationships and place of A. brandorffi within the genus Alona are discussed.  相似文献   

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