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951.
952.
A photomap of the banding pattern of the salivary gland chromosomes of Anopheles stephensi Liston, which is first of its kind, has been prepared. The salivary chromosome complement consists of five arms, the shortest of which represents the telocentric X-chromosome, and the remaining four the autosomal arms. A comparison has been made of the banding pattern of this species with other species of the subgenus Cellia. 相似文献
953.
R Wever J H Van Drooge A O Muijsers E P Bakker B F Van Gelker 《European journal of biochemistry》1977,73(1):149-154
The effect of CO on the optical absorbance spectrum of partially reduced cytochrome c oxidase has been studied. The changes at 432 and 590 nm suggest that the cytochrome alpha2/3+ - CO compound is formed preferentially and that concomitantly a second electron is taken up by the enzyme. From the CO-induced changes at 830 nm it is concluded that in the partially reduced enzyme addition of CO causes reoxidation of the copper component of cytochrome c oxidase. Addition of CO to partially reduced enzyme (2 electrons per 4 metal ions) also brings about a decrease in the intensities of electron paramagnetic resonance signals of high-spin heme iron near g = 6 and of the low-spin heme at g = 2.6. Concomitantly both the low-spin heme a signal at g = 3 and the copper signal at g = 2 increase in intensity. These results demonstrate that formation of the reduced diamagnetic cytochrome a3 - CO compound is accompanied by reoxidation of both the copper component detectable by electron paramagnetic resonance and possibly also by cytochrome a. 相似文献
954.
955.
Nganasans is a small samodyen-speaking ethnic group originated from several clans of reindeer hunters. Pedigree studies revealed no consanguineous matings of uncle-niece, aunt-nephew, first cousins type among 120 families studied. Rather rarely mating between second cousins could be observed. The reviewed traditional kindship system based on bilateral exogamy is an explanation. Data on 12 blood systems and 6 red cell enzymes distribution in two main localities almost totally studied have been presented. No A2, r, K, MS alleles were observed. Hgh frequencies of Ns, R2, Fya, Jka, Gm1 have been found. Diegoa was seen in only one family. Polymorphism on PGM1, 6-PGD, AK and AP, monomorphism on LDH and MDH has been observed. 相似文献
956.
The paper explains how the formulas for calculating the surface area of the prolate spheroid, which a nucleus resembles, can be changed by suitable substitutions into formulas based on measured diameters l and k [mm] of the nucleus approach side surface, magnified 3.000 times, and on a mixed cyclometric function dependent on the axial ratio. Their values established for distinct axial ratios are compiled in a table. The values of the mixed cyclometric function are to be calculated for any other axial ratio according to a formula based on linear interpolation. The nucleus surface Omu is obtained in the natural order of magnitude [micron2]. In case of constant axial ratio, the surface area values form a second-order arithmetic progression, and a recursion formula has been developed to check the values of its terms. In case of nuclei of spherical shape or constant small diameter k, the surface area formulas may be simplified. Numeral examples serve for explanation. For all measured-value combinations involved, a second part, which is being prepared, will contain a complete table of function values, which is referred to in the Appendix and from which the values of the natural surface areas of spheroid nuclei can be gathered. 相似文献
957.
H O Hofer 《Gegenbaurs morphologisches Jahrbuch》1977,123(6):836-856
Nycticebus coucang is typically strepsirrhine. This condition is basically the same in all prosimians except Tarsius. The rhinarium shows a labial part; the marked furrow in its median plane clefts the margin of the upper lip. The latter is attached to the gum between the median incisors by means of paired folds (not corresponding to a frenulum labii superioris). The labial cleft is continued in the sulcus papillae palatinae. The ductus vomeronasalis opens into the ductus nasoplatinus which, in turn, enters the aboral part of the sulcus palatinus. Thus strepsirrhinism provides, occasionally, an open communication of the olfactory systems (nose, vomeronasal organ) with the environment in front of the rhinarium. Strepsirrhine primates possess an internarium very similar to the one of platyrrhine monkeys. The shape of the nostrils is not characteristics for strepsirrhinism. A split-lip condition is likely ancestral to the complete lip condition, since it is found in several stems of mammals, especially in archaic forms. Strepsirrhinism, such as in lemuroid prosimians, is probably just one case of the primitive split-lip condition. Therefore, a median furrow in the external hairy skin of the upper lip, found in some platyrrhine monkeys, could be a rudiment of a cleft, indicating that a kind of a split lip condition was ancestral to the undivided lips of platyrrhine monkeys. Taste buds occur in the epithelium of the lateral surface of the papilla palatina of Nycticebus. Other lorisid prosimians have not been studied in this respect. The taste buds test water soluble substances entering the sulcus either way. These substances may come from the environment entering the sulcus through the labial cleft. 相似文献
958.
P. O. Fanger J. Højbjerre J. O. B. Thomsen 《International journal of biometeorology》1977,21(1):44-50
Preferred room temperatures were determined for 16 winter swimmers who had been exposed to cold shock daily by bathing in the sea (0–6°C) during at least two winter seasons. Each subject participated in one comfort experiment (2 1/2 h) in an environmental test chamber, where the preferred ambient temperature was determined by adjusting it according to his wishes. The subjects were sedentary and clothed in a standard uniform. Skin temperatures, rectal temperature and evaporative weight loss were measured. The results were compared with similar data for two other groups: (a) a control group of 64 normal subjects and (b) 16 persons who had been working 8 h a day at 8°C during at least 6 months in the meat packing industry. The results showed no significant differences between the ambient temperatures preferred by the three groups of subjects. This indicated that man cannot be adapted to prefer lower ambient temperatures by exposing him daily to cold. 相似文献
959.
960.
A cyclic AMP-adenosine binding protein from mouse liver has been purified to apparent homogeneity as judged by polyacrylamide gel electrophoresis in the absence and presence of sodium dodecyl sulfate and by analytical ultracentrifugation. The binding protein had a Stokes radium of 48 A based on gel chromatography. Both the purified binding protein and the binding activity in fresh cytosol sedimented as 9 S on sucrose gradient centrifugation. The homogeneous protein had a sedimentation coefficient (S20, w) of 8.8 x 10-13 s, as calculated from sedimentation velocity experiments. By use of the Stokes radius and S20, w', the molecular weight was calculated to be 180,000. The protein was composed of polypeptides having the same molecular weight of 45,000 as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and thus appeared to consist of four subunits of equal size. The isoelectric point, pI = 5.7. The binding capacity for cyclic AMP increased by preincubating the receptor protein in the presence of Mg2+ ATP. This process, tentatively termed activation, was studied in some detail and was shown not be be be accompanied by dissociation, aggregation, or phosphorylation of the binding protein. Cyclic AMP was bound to the protein with an apparent dissociation constant (Kd) of 1.5 x 10-7 M. The binding of cyclic AMP was competitively inhibited by adenosine, AMP, ADP, and ATP whose inhibition constants were 8 x 10-7 M, 1.2X 10-6 M, 1.5 X 10-6 M, and higher than 5 x 10-6 M respectively. A hyperbolic Scatchard plot was obtained for the binding of adenosine to the activated binding protein, indicating more than one site for adenosine. The binding of adenosine to the site with the highest affinity (Kd=2 x 10-7 M) for this nucleoside was not suppressed by excess cyclic AMP and was thus different from the aforementioned cyclic AMP binding site. Cyclic GMP, GMP, guanosine, cyclic IMP, IMP, and inosine did not inhibit the binding of either cyclic AMP or adenosine. The binding protein had no cyclic AMP phosphodiesterase, adenosine deaminase, phosphofructokinase, or protein kinase activities, nor does it inhibit the catalytic subunit of the cyclic AMP-dependent protein kinase. 相似文献