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1.
2004~2005年,在陕西省南部米仓山黎坪国家森林公园研究了秦岭蝎蛉Panorpa qinlingensisChouetRan的年生活史和生物学习性,通过饲养,成功获得卵、幼虫、蛹等虫态。结果表明,秦岭蝎蛉在米仓山1年发生2代,以预蛹在土室里越冬,5月中旬始见越冬代成虫,5月中旬末~6月上旬为越冬代成虫羽化盛期,7月下旬~8月中旬为第1代成虫羽化盛期,成虫在室内可存活35~60 d。羽化近1周后开始交尾,交尾4~8 d后开始产卵,单雌产卵量35~180粒,卵期5~9 d;幼虫型,共4龄,历期38~50d;蛹为强颚离蛹,蛹期8~18 d。记述了主要生物学习性。  相似文献   

2.
The present paper reports the chromosome numbers and karyotypes of five species in Polygonatum from Anhui of China. The materials used in this work are listed in Table 1, Photomicrographs of somatic metaphase and karyograms of the five species of Polygonatum in Plate 1, 2, 3, the idiograms in Fig. 1-11 and a comparison of the karyotype of them is provided in Table 2. The results are shown as follows: 1. Polygonatum odoratum (Mill.)Druce Two materials were examined. One from Mt. Huangshan, Anhui, has 2n= 16 = 10m (3sc)+ 6sm (Plate 1 :A, B). The idiogram is shown in Fig. 1. The chromosomes range in length from 2.85 to 8.85 μm, with the total length 48.63μm and the ratio of the longest to the shortest 3.11, The karyotype belong to Stebbins’(1971) 2B. The two chromosomes of the first pair have arm ratios 1.01 and 1.29 respectively, and The first pair has one chromosome carrying a satellite attached to the short arm, showing heterozyosity .The chromosome num ber of 2n= 16 in P. odoratum and its karyotype are reported for the first time. The other from Langyashan, Chu - xian, Anhui, is found to have 2n = 18 = 10m (Isc)+2sm+6st(2sc) (Plate 1: C, D). The idiogram is shown in Fig. 2. The chromosomes range in length from 2.43 to 8.29μm, with the total length 46.67µm and the ratio of the longest to the shortest 3.41. The karyotype is also of 2B. In a somatic chromosome complement the 2nd pair have one chromosome carrying a satellite attached to the long arm, showing heterozygosity. 2. Polygonatum filipes Merr. Two materials were examined. One from the Huangshan, Anhui is found to have two cytotypes: 2n= 16 and 2n=22. This paper reports one of them. The karyotype formula is 2n=22=8m+8sm(2sc)+6st(Plate 3: Q, R). The idiogram is shown in Fig. 3. The chromosomes range in length from 2.55- 5.85μm, with the total length 45.01 μm and the ratio of the longest to the shortest 2.29. The karyotype belongs to 3B. The other material from the Fangchang, Anhui, is shown to have four cytitypes: 2n= 14, 2n= 16, 2n=20 (Plate 3: W) and 2n=22. This paper reports two of them. Type I: the karytype formula is 2n=14=10m+4sm (Plate 3: S, T). The idiogram is shown in Fig. 5. The chromosomes range in length from 2.59 to 7.61μm, the total length 37.44μm and the ratio of the longest to the shortest is 2.94. the karyotype belongs to 2B. Type II :The karyotype formula is 2n=16=8m+4sm+4st (Plate 3: U, V). The idiogram is shown in Fig. 4. The chromosomes range in length from 2.65 to 8.21 μm, the total length 46.01 μm and the ratio of the longest to the shortest 3.10. The karyotype belongs to 2B. The chromosome numbers of 2n=20, 2n= 14 and 2n=22, and karyotype of 2n= 14 and 2n=22 in P. filipes are reported for the first time. 3. Polygonatum cytonema Hua Two materials were examined. One from the Langyashan, Chuxian, anhui, is found to have 2n = 18 = 8m (2sc)+ 6sm+ 4st (Plate 2: K, L). The idiogram is shown in Fig. 7. The chromosomes range in length from 3.41 to 9.21 μm, the total length 56.34μm and the ratio of the longest to the shortest is 2.70. The karyotype belongs to 2B. The other material from the Huangshan, Anhui, has two cytotypes: 2n=20 and 2n= 22. Type I: The karyotype formula is 2n= 20= 8m+ 6sm+ 6st (Plate 2: M, N). The idiogram is shown in Fig. 8. The chromosomes range in length from 1.75 to 5.03μm, with the total length 32. 91μm and the ratio of the longest to the shortest 2. 87. The karyotype is also of 2B. Type II: The karyotype formula is 2n=22=6m+ 8sm+4st+ 4t (Plate 2: O, P ). The idiogram is Shown in Fig. 10. The chromosomes range in length from 1.75 to 4.95 μm, with total length 35.05μm and the ratio of the longest to the shortest 2.83. The karyotype brlongs to 3B. 4. Polygonatum desoulayi kom. The material from Xuancheng, Anhui, is found to have karyotype 2n = 22 = 10m (2sc) + 6sm (lsc) + 6st ( Plate 2. I, J). The idiogram is shown in Fig. 6. The chromosomes range in length from 1.86 to 5.61μm, with the total length 41.98μm and the ratio of the longest to the shortest 3.02. The karyotype is also of 3B. The first pair has one chromosome carrying a satellite attached to the long arm, showing heterozygosity. The chromosome number and karyotype of Chinese material are reported for the first time. 5. Polygonatum verticillatum (L.) All. The material from the Langyashan, Chuxian, Anhui is found to have two cytotypes. Type 1: the karyotype formula is 2n = 18 = 2m+ 2sm+ 10st+ 2t+ 2T (Plate 1: G, H). The idiogram is shown in Fig.9. The chromosomes range in length from 1.86 to 4.03μm, with total length 28.28μm and the ratio of the longest to the shortest 2.17. The karyotype classification belongs to 3B. Type II: The karyotype formula is 2n=24=6m+4sm+12st+2T (Plate 1: E, F). The idiogram is shown in Fig. II. The chromosomes range in length from 2.01 to 5.03μm, with total length 41.36μm and the ratio of longest to shortest 2.50. The karyotype is also of 3B. The chromosome numbers and karyotypes of Chinese material are reported for the first time.  相似文献   

3.
蔡立君  李军  花保祯 《昆虫知识》2006,43(5):681-683,F0004
2004~2005年,在陕西省南部米仓山黎坪国家森林公园研究了秦岭蝎蛉Panorpa qinlingensis Chou et Ran的年生活史和生物学习性,通过饲养,成功获得卵、幼虫、蛹等虫态。结果表明,秦岭蝎蛉在米仓山1年发生2代,以预蛹在土室里越冬,5月中旬始见越冬代成虫,5月中旬末~6月上句为越冬代成虫羽化盛期,7月下旬~8月中句为第1代成虫羽化盛期,成虫在室内可存活35~60d。羽化近1周后开始交尾,交尾4~8d后开始产卵,单雌产卵量35~180粒,卵期5~9d;幼虫蝴型,共4龄。历期38~50d;蛹为强颚离蛹,蛹期8—18d。记述了主要生物学习性。  相似文献   

4.
A numerical method for determining the electrophoretic mobility of a polyelectrolyte-coated particle is presented. The particle surface is modeled as having a permeable layer of polyelectrolyte molecules anchored to its surface. Fluid flow within the polyelectrolyte layer is subject to Stokes drag arising from the polyelectrolyte segments. The method allows arbitrary distribution of polymer segments and charge density normal to the surface to be used. The hydrodynamic plane of shear may also be varied. The potential profile is determined by a numerical solution to the nonlinearized Poisson-Boltzmann equation. The potential profile is then used in a numerical solution to the Navier-Stokes equation to give the required mobility. The use of the nonlinearized Poisson-Boltzmann equation extends the results to higher charge density/lower ionic strength conditions than previous treatments. The surface potentials and mobilities for three limiting charge distributions are compared for both the linear and nonlinear treatments to delimit the range of validity of the linear treatment. The utility of the numerical, nonlinear treatment is demonstrated by an improved fit to the electrophoretic mobility of human erythrocytes as a function of ionic strength in the range 10 to 150 mM.  相似文献   

5.
This paper reports the studies of overall embryology of Glycyrrhiza uralensis Fisch. Development of the anther wall follows the dicotyledonous type. The cytokinesis of the microspore mother cell in meiosis is of simultaneous type. The arrangement of microspores in tetrad is tetrahedral, isobilateral and decussate. Microspores have various types of abortive to development. Mature pollen grain is of the 2-celled type. The ovule is bitegminous, crassinucellate and campylotropous. The megaspore mother cell gives rise to unequal dyad and then linear tetrad. The chalazal megaspore, the second or the third megaspore towards the micropylar end are functional megaspore. The development of the embryo sac conforms to the Polygonum type. Mature embryo sac has various types of variation. The fertilization belongs to the premitotic type of syngamy. The development of most embryoes belongs to the Onagrad type. The development of the endosperm belongs to the nuclear type and the endosperm near the chalazal end develops into haustorium.  相似文献   

6.
The crystal structure of tetragonal hen egg-white lysozyme at a hydrostatic pressure of 1000 atmospheres has been determined by X-ray diffraction to a nominal resolution of 2 A. The crystals, originally grown in 0.83 M-NaCl, had to be transferred to 1.4 M-NaCl to prevent crystal cracking at 300 to 400 atm. The a and b axes of the unit cell contracted by 0.6%, whilst the c axis increased by 0.1%. The unit cell volume contracted by 1.1%. Both the 1 atm and the 1000 atm structures were refined by restrained least-squares to yield final R factors of 14.9% in each case. Since the data were collected by an accurate difference protocol, the change in structure is considered to be more accurate than the absolute structure. The probable accuracy of the atomic shifts is shown to be +/- 0.06 A. The estimated volume decrease of the whole molecule corresponded to an isothermal compressibility of 4.7 X 10(-3) kbar-1. The contraction was non-uniformly distributed. Domain 2 (residues 40 to 88) was essentially incompressible, whilst domain 1 (residues 1 to 39, 89 to 129) had a compressibility of 5.7 X 10(-3) kbar-1. The interdomain region was also compressible. The average B factor decreased about 1 A2 at 1000 atm, but there was a wide range of decreases and increases in individual values. The pressure-induced deformation was analyzed with difference distance matrices. The beta-sheet (residues 42 to 60) and helix 2 (residues 24 to 36) were deformed the least under pressure. The other helices were more deformed and one loop region (residues 61 to 87) actually appeared to expand. The main-chain atoms of the beta-sheet and helix 2 were used to perform a least-squares superposition of the 1 atm and 1000 atm models. The root-mean-square pressure-induced shift for all atoms was 0.2 A, with a few atoms moving more than 1 A. There was no evidence for co-ordinated movement about the hinge axis defined by alpha carbon atoms 38 and 97. The 1 atm and 1000 atm refined structures included 151 and 163 ordered water molecules, respectively. The changes in these ordered water molecules and the mean compressibility of all of the solvent in the crystal will be described elsewhere.  相似文献   

7.
1. The selectivities of the ion channels underlying the action potential and the hyperpolarizing response to acetylcholine of the GH cell of Onchidium have been analysed. 2. The rising phase of the action potential is due to an increase in the permeability of the membrane to both Na+ and Ca2+. The Na+ channel is permeable to Li+ and is somewhat permeable to formamidinium, guanidinium and ammonium ions. The Ca2+ channel is permeable to Sr2+ and Ba2+, but not to Mn2+ and Mg2+. 3. The Cl- channel operated by ACh is permeable to chlorate, but not to formate and propionate ions. 4. The selectivities of these channels are similar to those of a number of other channels in other organisms.  相似文献   

8.
The functional significance of the ciliary interconnections and cupula has been reviewed. The ciliary interconnecting systems are divided into 2 types, i.e. side links and tip links. The side links acts to maintain the regular distance between the cilia thereby keeping the geometrical arrangement of the entire sensory hair bundle intact as well as to prevent close contact between neighbouring cilia. The tip links, stretching upwards from the tips of the shorter stereocilia to their taller neighbouring shafts, are actually involved in mechanoelectrical transduction. The cupula is composed of the cupula and subcupular meshwork. The subcupular meshwork consists of long branching filaments cross-bridged to one another. The cupula would function as a rigid plate and equally distribute the shear force of the cupula to all the ciliary bundles. The subcupular meshwork may play a role in the transmission of the shear strain force of the cupula to the ciliary bundle and may also exert an additional damping effect in order to prevent unwanted vibrations.  相似文献   

9.
湖南土家族的体质特征   总被引:20,自引:8,他引:12  
以20至69岁的湖南土家族人为观察测量对象,根据1392人(男896,女496)的身高,1038人(男668,女370)的头部测量,364人(男235,女129)的五官测量和观察结果,分析该民族的体质特征,并与国内其他民族相比较。  相似文献   

10.
黑缘红瓢虫对6种杀虫剂的敏感性测定   总被引:1,自引:0,他引:1  
用点滴法在室内初步测定3黑缘红瓢虫Chilocorus rubidusHope幼虫对敌敌畏、氰戊菊酯、氟氯氰菊酯、硫丹、氧化乐果、灭多威等6种果园常用杀虫剂的敏威性。结果表明:黑缘红瓢虫幼虫对6种杀虫剂的敏感性依次为:氰戊菊酯、氟氯氰菊酯、硫丹、氧化乐果、敌敌畏、灭多威。LD50按以下次序增大:灭多威,氟氯氰菊酯,氧化乐果,氰戊菊酯,敌敌畏,硫丹。可见,硫丹对黑缘红瓢虫毒力最小,是最安全。敌敌畏等有机磷杀虫剂对它的毒力也较低,而拟除虫菊酯类药剂对黑缘红瓢虫的毒力则很高。同种药剂对不同用药水平地区的黑缘红瓢虫成虫的毒力差异显著,黑缘红瓢虫对氟氯氰菊酯和氰戊菊酯分别产生了5.4和7.6倍的抗药性,是羧酸酯酶活性提高所致。不同种类杀虫剂对黑缘红瓢虫和朝鲜球坚蚧Didesmococcus koreanusBorchs的选择指数差异极为显著,依次为硫丹、灭多威、敌敌畏、氰戊菊酯、氧化乐果、氟氯氰菊酯,如硫丹为2.6,而氟氯氰菊酯仅为0.04。硫丹是防治抗性朝鲜球坚蚧比较理想的一种杀虫剂。  相似文献   

11.
The Schmoluchowski equation is introduced into the problem of single file ion diffusion in a channel. The ions mutually interact due to coulomb repulsion and are also subject to a single ion potential due to the channel. The positions of the ions are represented by a continuous co-ordinate. The problem is reduced to the solution of a pair of transfer integral equations. The resistivity of finite and infinite channels is calculated for various dielectric constants and mean ionic separations. The ionic density for finite channels is also calculated. The results clearly demonstrate that strong coulomb interaction leads to a co-operative motion of the ions across channels.  相似文献   

12.
The electron-withdrawing nitro substituents of 2,4,6-trinitrotoluene (TNT) make the aromatic ring highly resistant to oxidative transformation. The typical biological transformation of TNT involves reduction of one or more of the nitro groups of the ring to produce the corresponding amine. Reduction of a single nitro substituent of TNT to an amino substituent increases the electron density of the aromatic nucleus considerably. The comparatively electron-dense nuclei of the aminodinitrotoluene (ADNT) isomers would be expected to be more susceptible to oxygenase attack than TNT. The hypothesis was tested by evaluating three nitroarene dioxygenases for the ability to hydroxylate the ADNT isomers. The predominant reaction was dioxygenation of the ring to yield nitrite and the corresponding aminomethylnitrocatechol. A secondary reaction was benzylic monooxygenation to form aminodinitrobenzyl alcohol. The substrate preferences and catalytic specificities of the three enzymes differed considerably. The discovery that the ADNT isomers are substrates for the nitroarene dioxygenases reveals the potential for extensive bacterial transformation of TNT under aerobic conditions.  相似文献   

13.
A comprehensive model of stem and root diameter variation was developed. The stem (or root) was represented using two coaxial cylinders corresponding with the mature xylem and the extensible tissues. The extensible tissues were assumed to behave as a single cell separated from the mature xylem by a virtual membrane. The mature xylem and the extensible tissues are able to dilate with temperature and grow. Moreover, the extensible tissues are able to shrink and swell according to water flow intensity. The model is mainly based on the calculation of water volume flows in the "single cell" that are described using the principles of irreversible thermodynamics. The elastic response to storage volume and plastic extension accompanying growth are described. The model simulates diameter variation due to temperature, solute accumulation, and xylem, water potential. The model was applied to the peach (Prunus persica) stem and to the plum (Prunus domestica x Prunus spinosa) root. The simulation outputs corresponded well with the diameter variation observed. The model predicts that variations of turgor pressure and osmotic potential are smaller than the variations of xylem water potential. It also demonstrates correlations between the xylem water potential, the turgor pressure, the elastic modulus, and the osmotic potential. The relationship between the diameter and the xylem water potential exhibits a substantial hysteresis, as observed in field data. A sensitivity analysis using the model parameters showed that growth and shrinkage were highly sensitive to the initial values of the turgor pressure and to the reflection coefficient of solutes. Shrinkage and growth were sensitive to elastic modulus and wall-yielding threshold pressure, respectively. The model was not sensitive to changes in temperature.  相似文献   

14.
The brindled mutant mouse is a useful model to study Menkes kinky-hair syndrome. The metabolic dysfunctions in both human and rodent are related to insufficient levels of bioavailable copper. Recently, copper supplementation therapy has been able both to prevent the appearance of various neuropathological changes and to prolong the life of these mutant mice. The optimum conditions for supplementation have been shown to be two intraperitoneal injections on postnatal days 7 and 10. The present study reports on the brain copper concentrations before, during and after the intraperitoneal copper therapy. The results demonstrate that postnatal days 7 and 10 correspond to two important epochs in copper homoeostasis. The supplementation therapy seems to provide sufficient bioavailable copper to respond to the needs of the animal at these crucial time points. The results are discussed in terms of their importance to the human copper disorder.  相似文献   

15.
Synopsis The coelacanth, Latimeria chalumnae, is often referred to as a living relic. The opportunity to examine its biochemical molecular structure was sought in an effort to define the degree of its genetic variability. The coelacanth is thought to live only in a small area around the Comoro Islands in the Western Indian Ocean. The scenario presented suggests that the coelacanth may have lost genetic variability as a result of genetic drift within a small population. The narrow geographic range of the coelacanth suggests adjustment to a relatively limited environment. The loss of specific alleles through genetic drift can reduce the ability of a fish population to adapt to changes in environmental conditions. The coelacanth needs strong conservation measures to be taken to curtail the capture of specimens and for the protection of its limited natural habitat.  相似文献   

16.
The IAA oxidase activity was studied during the culture of dormant apple embryos. The effect of different factors on this enzyme activity was investigated either by adding them to the reaction mixture or to the culture medium. Phloridzin was found to be the best phenolic cofactor. The development of IAA oxidase activity was stimulated by phloridzin and GA3. The properties of apple embryos IAA oxidase allow to postulate the presence of two enzyme systems able to oxidize IAA in the material studied. The involvement of peroxidase activity in IAA oxidation was also investigated. The differences in the changes of peroxidase and IAA oxidase activities during the culture of dormant apple embryos do not permit to consider the activity of peroxidases to be identical with that of IAA oxidase.  相似文献   

17.
The development of the anther wall follows Basic-type. The cytokinesis at the time of pollen mother cell meiosis conforms to successive type. The arrangement of the microspores in the tetrad is referred to isobilateral. The primary wall between the generative cell and the vegetative cell is callose. The callose wall is easily detected under the fluorescence microscope. The mature pollen grain is 2-celled type. The ovule is bitegminous, tenui-nucellar and anatropous. The development of the female gametophyte follows Fritillaria-type. The mature embryo sac. consists of the six cells including the seven nuclei. The fertilization is referred to the premitotic syngamy type. The fusion of the female and male nucleoli is not observed at the end of the fertilization. The division of the primary endosperm nucleus is earlier than that of the zygote. The development of the endosperm is referred to nuclear type. The division of the zygote is transverse of longitudinal, the development of the embryo conforms to Onagradtype. When the seed is mature, the embryo is at the proembryo stage without differentiation and the endosperm cells are not absorbed.  相似文献   

18.
A string-like carbon fiber was found to be very suitable as a working electrode material for direct electrochemical oxidation of β-nicotinamide adenine dinucleotide reduced form (NADH), and direct use of it for an enzyme reactor was possible. The electrochemical NAD+ recycling system was applied to glucose dehydrogenase (GDH) and to the recombinant formate dehydrogenase (RFDH) reactors. The maximum oxidation current value increased to 3.9 mA in the case of the GDH reactor. The remaining GDH activity after the reaction for 10 h amounted to 57% of the initial level. The remaining NAD+ activity amounted to 78% of the initial level. The current efficiency was calculated to be 80%. Furthermore, RFDH, which was more stable than GDH, was applied to the system. The maximum current value reached 5.9 mA. The remaining RFDH activity after reaction for 10 h amounted to 81% of the initial level. The remaining NAD+ activity was 78% of the initial level. The current efficiency was calculated to be 73%. Based on these results, both the enzyme and NAD+ were found to be acceptably stable in the electrochemical NAD+ recycling system.  相似文献   

19.
The anatomical basis for the application of neurovascular pedicled muscle transfers of the digastric and stylohyoid muscles in the treatment of velopharynx incompetence is described. The fact that the neurovascular pedicle is located in the cranial third of the muscle bellies provides the safety of the operative procedure. The muscles have to be dissected with respect to that. The direction in which the transferred muscles pull is described. The muscle transposition is combined with the classic Wardill-Kilner operation to lengthen the soft palate. The transferred muscles have to avoid scar contraction and shortening of the soft palate and to gain a muscular function of the soft palate. The clinical use is justified in rare cases as demonstrated in one case.  相似文献   

20.
The basic regularities of the formation and realization of immunological memory to staphylococcal corpuscular antigen were studied in adoptive transfer experiments on CBA mice. The capacity of spleen cells for generating anamnestic response to staphylococci in the body of irradiated syngeneic recipients appeared on day 3 after the immunization of donors. The formation of immunological memory to staphylococci in mice was shown to be directly related to the dose of the antigen. The study also revealed that intact splenocytes did not suppress the realization of immunological memory to staphylococci in the system of adoptive transfer. The conclusion of the absence of the "isogeneic barrier" for memory cells specific to staphylococcal corpuscular antigen was made.  相似文献   

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