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1.
恙螨一新种——青海恙螨   总被引:1,自引:1,他引:0  
1959年7月间,广东省卫生防疫站一些同志到青海省工作,采得6只恙螨标本,交由笔者鉴定,认为是一个新种,定名为青海恙螨Trombicula tsinghaiensis。青海省恙螨之发现,本文尚为首次记录。 青海恙螨Trombicula tsinghaiensis,新种(图1—6)  相似文献   

2.
从采自新疆博乐县阿拉山口(海拔290 m)室内灰仓鼠伏龙芝亚种 Cricetulus migratorius caesius耳壳内的一批纤恙螨标本鉴定中发现中国新记录亚属——爱柯纤恙螨亚属 Ericotrombidium中的一个新种,定名为博乐纤恙螨 Leptotrombidium (E.) bolei sp.nov.,它与美丽纤恙螨L.(E.)pulchrum(Sosnina,1950)及索氏纤恙螨L.(E.)sokolovi Kudryshova,1984比较近似,但本新种IP及盾板量度除 AM外均较大,PW-SB≥PL,可与前者区别;IP较小,平均787,幅度763—821,DS较少,排列规则:2+8.6.6.4.2=28,可与后者区别。  相似文献   

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1978年7月,周曼殊、张中干、王成弟等同志,在四川省南江县秦巴山系进行调查中从岩松鼠(Sciurotamias davidianus Milne-Edwaards)耳壳内采得一些恙螨幼虫,发现其中一只属于新种,命名南江囊棒恙螨。 1960年7月,陈宁宇等同志参加自然疫源地调查,在四川省黑水县903林场阔叶林  相似文献   

5.
恙螨生活史的研究(真螨目, 恙螨科)(恙螨研究XXII)   总被引:1,自引:0,他引:1  
徐荫祺 《昆虫学报》1959,(5):452-459
绪言 恙螨由于传播恙虫病,十九世纪末叶以来,研究的人很多。1945年以前的儿十年中,世界各国有许多学者,进行过恙螨的饲养工作来研究它们的生活史,但是由于虫体太小,饲养方法的不够完善,若虫和成虫的食料不了解等原因,都没有成功,造成了研究整个生活史的许多困难。最近十几年中由于饲养方法不断的改进,同时又找到了若虫和成虫的  相似文献   

6.
陕西恙螨二新种(蜱螨目:恙螨科,列恙螨科)   总被引:1,自引:1,他引:0  
本文记述从陕西省秦岭南坡采集到的恙螨两新种。文中所用量度单位均为微米。模式标本存放于陕西省卫生防疫站。  相似文献   

7.
自Vercammen-Grandjeau(1960,1965)及Suzuki(1976)将Audy(1956)所建立的蜥恙螨属Siseca归于真恙螨属Eutrombicula Ewing(1938)内为一亚属以来,国外学者报道过蜥恙螨亚属7种,国内徐梅吉(1982)报告一种,本文首次报道采自鸟体的蜥恙螨亚属一新种,故迄今世界上已知蜥恙螨亚属有9种。  相似文献   

8.
一、绪 言 与氏阿康恙螨Acomatacarus yosanoi Fukuzumi et Obata,1953的精胞发现及其间接交配试验的结果,促使我们进一步考虑这一现象的普遍性问题。 1957年春季中国人民解放军军事医学科学院获得了大批恙螨幼虫,并在实验室中饲养到达成虫,为了帮助我们了解这一生活史特性,故在同年5月和8月之间把饲养所得的成虫供给我们观察了一个时期,这些成虫是地里恙螨Trombicula deliensis Walch,1923,  相似文献   

9.
本文记述从云南省西部及南部地区啮齿动物和蝙蝠体上采到的恙螨7新种,包括纤恙螨属Leptotrombidium 6种及囊棒恙螨属Ascoschoengastia 1种。全部模式标本均保存于云南省流行病防治研究所。 1. 徐氏纤恙螨,新种Leptotrombidium(Leptotrombidium)hsui sp.nov.(图1—5) 鉴别特征 此螨系trapezoidum种团中之螨种,与长毛纤恙螨L.(L.)longisetum Yu  相似文献   

10.
川西恙螨二新种(真螨目:恙螨科)   总被引:1,自引:1,他引:0  
从四川省西部采到两种恙螨,经研究系科学上未报道的新种,现记述如下: 鼠兔叶片恙螨 Trombiculindus(Plumosicola)ochotonae,新种(图1—3) 中型恙螨,体呈椭圆形。螯肢片上具三角冠。螯鞘毛分枝。鬚肢毛式N-N-BNN。鬚跗毛fT=7B。鬚肢爪3分叉。背板呈宽长方形,上具刻点,宽约为长的2.25。前中毛位于前侧毛线之下方。SB位于后侧毛线上或略高。PL>AL。眼2×2。背板上各部量度(单位:微米)如下:  相似文献   

11.
Xia Z  Zhuang J 《Luminescence》2012,27(5):379-381
A novel blue‐emitting Sr3.5Y6.5O2(PO4)1.5(SiO4)4.5:Eu2+ phosphor was synthesized via a solid‐state reaction. Powder X‐ray diffraction (XRD) analysis demonstrated that the Sr3.5Y6.5O2(PO4)1.5(SiO4)4.5 host had a hexagonal crystal structure in the space group P63/m and unit cell parameters a = 9.418 Å, c = 6.900 Å. The as‐prepared phosphor showed a blue emission and all the main emission peaks were located at around 466 nm for different excitation wavelengths of 297, 333 and 391 nm. The temperature dependence of the photoluminescence property was investigated in the range 20–250 °C, and the emission intensity decreased to 71% of the initial value at room temperature on increasing the temperature to 150 °C. According to the classical theory of fluorescent thermal quenching, the activation energy (ΔE) for the thermal quenching luminescence of the as‐prepared Sr3.45Y6.5O2(PO4)1.5(SiO4)4.5:0.05Eu2+ phosphor was determined to be 0.20 eV. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

12.
For the rational design of a stable collagen triple helix according to the conventional rule that the pyrrolidine puckerings of Pro, 4-hydroxyproline (Hyp) and 4-fluoroproline (fPro) should be down at the X-position and up at the Y-position in the X-Y-Gly repeated sequence for enhancing the triple helix propensities of collagen model peptides, a series of peptides were prepared in which X- and Y-positions were altogether occupied by Hyp(R), Hyp(S), fPro(R) or fPro(S). Contrary to our presumption that inducing the X-Y residues to adopt a down-up conformation would result in an increase in the thermal stability of peptides, the triple helices of (Hyp(S)-Hyp(R)-Gly)(10) and (fPro(S)-fPro(R)-Gly)(10) were less stable than those of (Pro-Hyp(R)-Gly)(10) and (Pro-fPro(R)-Gly)(10), respectively. As reported by B?chinger's and Zagari's groups, (Hyp(R)-Hyp(R)-Gly)(10) which could have an up-up conformation unfavorable for the triple helix, formed a triple helix that has a high thermal stability close to that of (Pro-Hyp(R)-Gly)(10). These results clearly show that the empirical rule based on the conformational preference of pyrrolidine ring at each of X and Y residues should not be regarded as still valid, at least for predicting the stability of collagen models in which both X and Y residues have electronegative groups at the 4-position.  相似文献   

13.
The enzymes chlorocatechol-1,2-dioxygenase, chloromuconate cycloisomerase, dienelactone hydrolase, and maleylacetate reductase allow Ralstonia eutropha JMP134(pJP4) to degrade chlorocatechols formed during growth in 2,4-dichlorophenoxyacetate or 3-chlorobenzoate (3-CB). There are two gene modules located in plasmid pJP4, tfdC(I)D(I)E(I)F(I) (module I) and tfdD(II)C(II)E(II)F(II) (module II), putatively encoding these enzymes. To assess the role of both tfd modules in the degradation of chloroaromatics, each module was cloned into the medium-copy-number plasmid vector pBBR1MCS-2 under the control of the tfdR regulatory gene. These constructs were introduced into R. eutropha JMP222 (a JMP134 derivative lacking pJP4) and Pseudomonas putida KT2442, two strains able to transform 3-CB into chlorocatechols. Specific activities in cell extracts of chlorocatechol-1,2-dioxygenase (tfdC), chloromuconate cycloisomerase (tfdD), and dienelactone hydrolase (tfdE) were 2 to 50 times higher for microorganisms containing module I compared to those containing module II. In contrast, a significantly (50-fold) higher activity of maleylacetate reductase (tfdF) was observed in cell extracts of microorganisms containing module II compared to module I. The R. eutropha JMP222 derivative containing tfdR-tfdC(I)D(I)E(I)F(I) grew four times faster in liquid cultures with 3-CB as a sole carbon and energy source than in cultures containing tfdR-tfdD(II)C(II)E(II)F(II). In the case of P. putida KT2442, only the derivative containing module I was able to grow in liquid cultures of 3-CB. These results indicate that efficient degradation of 3-CB by R. eutropha JMP134(pJP4) requires the two tfd modules such that TfdCDE is likely supplied primarily by module I, while TfdF is likely supplied by module II.  相似文献   

14.
Sim GE  Goh CJ  Loh CS 《Plant cell reports》2008,27(8):1281-1289
We analysed the endogenous cytokinin levels of Dendrobium Madame Thong-In seedlings grown in vitro during vegetative and flowering-inductive periods. HPLC was used to fractionate the extracts and radioimmunoassay (RIA) was used for assay of zeatin (Z), dihydrozeatin (DZ), N(6)-(Delta(2)-isopentenyl)-adenine (iP) and their derivatives. Coconut water used in experiments was found to contain high level (>136 pmol ml(-1)) of zeatin riboside (ZR). Protocorms and seedlings cultured in medium with coconut water were found to contain 0.5-3.9 pmol g(-1) FW of the cytokinins analysed. Seedlings (1.0-1.5 cm) cultured in flowering-inductive liquid medium containing 6-benzyladenine (BA, 4.4 muM) and coconut water (CW, 15%) contained up to 200 and 133 pmol g(-1) FW of iP and iPA, respectively. These levels were significantly higher than all other cytokinins analysed in seedlings of the same stage and were about 80- to 150-folds higher than seedlings cultured in non-inductive medium. During the transitional (vegetative to reproductive) stage, the endogenous levels of iP (178 pmol g(-1) FW) and iPA (63 pmol g(-1) FW) were also significantly higher than cytokinins in the zeatine (Z) and dihydrozeatin (DZ) families in the same seedlings. Seedlings that grew on inductive medium but remained vegetative contained lower levels of iPA. The importance of the profiles of iP and its derivatives in induction of in vitro flowering of D. Madame Thong-In is discussed.  相似文献   

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The biology of the fruit fly Bactrocera tau, an important horticultural pest, was studied under laboratory conditions at 25°C and 60–70% relative humidity on Cucurbita maxima. The duration of mating averaged 408.03 ± 235.93 min. After mating, the female fly had a preoviposition period of 11.7 ± 4.49 days. The oviposition rate was 9.9 ± 8.50 eggs and fecundity was 464.6 ± 67.98 eggs/female. Eggs were elliptical, smooth and shiny white, turning darker as hatching approached, and measured 1.30 ± 0.07 mm × 0.24 ± 0.04 mm. The chorion has polygonal microsculpturing and is species-specific with polygonal walls. The egg period lasts for 1.3 ± 0.41 days. The duration of the larval period is 1.2 ± 0.42, 1.7 ± 0.48 and 4.0 ± 0.94 days for first, second and third instars, respectively. Pupation occurs in the sand or soil and pupal periods are 7.0 ± 0.47 days. The life cycle from egg to adult was completed in 14.2 ± 1.69 days; the longevity of mated females and males was 130.33 ± 14.18 and 104.66 ± 31.21 days, respectively. At least two to three generations were observed from June 2008 to June 2009.  相似文献   

18.
R M Wartell 《Biopolymers》1972,11(4):745-759
Helix–coil transition curves are calculated for poly (dA) poly(dT) and poly (dA-dT) poly (dA-dT) using the integral equation approach of Goel and Montroll.5 The transitions are described by the loop entropy model with the exponent of the loop entropy factor, k, remaining an arbitrary constant. The theoretical calculations are compared with experimental transition curves of the two polymers. Results indicate that the stacking energies for these two polymers differ by about 1 kcal/mole of base pairs. Also, a fit between theory and experiment was not possible for k > 1.70.  相似文献   

19.
This article reports on the optical properties of Er3+ ions doped CdO–Bi2O3–B2O3 (CdBiB) glasses. The materials were characterized by optical absorption and emission spectra. By using Judd–Ofelt theory, the intensity parameters Ωλ (λ = 2, 4, 6) and also oscillatory strengths were calculated from the absorption spectra. The results were used to compute the radiative properties of Er3+:CdBiB glasses. The concentration quenching and energy transfer from Yb3+–Er3+ were explained. The stimulated emission cross‐section, full width at half maximum (FWHM) and FWHM × values are also calculated for all the Er3+:CdBiB glasses. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

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