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31.
Mominul Islam Nahid Frode Fossøy Bård G. Stokke Sajeda Begum Eivin Røskaft 《Bird Study》2019,66(1):141-144
House Crows Corvus splendens lay eggs with bluish-green ground colour and black or brown blotches and only one egg morph was believed to exist. Here, we confirm the existence of an immaculate, spotless blue egg morph that is clearly different from the regular egg morph. 相似文献
32.
33.
Büyükgüzel K 《Journal of economic entomology》2001,94(1):21-26
Effects of novobiocin, nalidixic, and oxolinic acids on the survival and development of the hymenopterous endoparasitoid Pimpla turionellae L. were investigated alone and in various combinations by rearing larvae aseptically on chemically defined synthetic diets. Effects varied with the levels and kinds of the antibiotics in the tested combinations. Among the tested antibiotics alone, only the lowest level of novobiocin enhanced the postlarval survival. Most of the combinations significantly increased the number of survivors in the postlarval developmental stages. Novobiocin in combination with nalidixic acid (6.0:2.0 mg) in the artificial diet produced a yield of 80.8% pupae and 69.4% adults, respectively. This combination also shortened the developmental time to adult emergence. Similarly, on most of the diets with combinations of the antibiotics, the development of the larvae up to adult stage was noticeably faster than those on the control diets. An approximately equals 50% reduction in the percentages of pupae and adults was recorded by 6.0 mg of novobiocin in combination with 0.75 mg of oxolinic acid compared with the control diet. Although this combination prolonged the complete development of the insect according to other novobiocin and oxolinic acid combinations, developmental time was significantly shorter than that with control diet. 相似文献
34.
Kvaløy K Nilsen H Steinsbekk KS Nedal A Monterotti B Akbari M Krokan HE 《Mutation research》2001,461(4):325-338
35.
The Mahogany/Attractin gene (Atrn) has been proposed as a downstream mediator of Agouti signaling because yellow hair color and obesity in lethal yellow (A(y)) mice are suppressed by the mahogany (Atrn(mg)) mutation. The present study examined the distribution of Atrn mRNA in the brain and spinal cord by in situ hybridization. Atrn mRNA was found widely distributed throughout the central nervous system, with high levels in regions of the olfactory system, some limbic structures, regions of the brainstem, cerebellum and spinal cord. In the hypothalamus, Atrn mRNA was found in specific nuclei including the suprachiasmatic nucleus, the supraoptic nucleus, the medial preoptic nucleus, the paraventricular hypothalamic nucleus, the ventromedial hypothalamic nucleus, and the arcuate nucleus. These results suggest a broad spectrum of physiological functions for the Atrn gene product. 相似文献
36.
Pacini A Quattrone A Denegri M Fiorillo C Nediani C Ramon y Cajal S Nassi P 《The Journal of biological chemistry》1999,274(49):35107-35112
37.
In conventional electrooptic studies the sample ionic strength must for technical reasons be kept below about 3 mm, which is only 2% of the ionic strength at physiological conditions. In particular for flexible polyelectrolytic macromolecules
it can in general not be ruled out that both the conformational average and dynamics at ionic strength 3 mm and below may differ significantly from what it is at physiological conditions. Here we report on the first electrooptic
study of human erythroid spectrin dimers and tetramers at ionic strengths higher than 3 mm. All measurements in this study were carried out at both ionic strength 4 mm (2.5 mm HEPES + 1 mm NaCl) and 53 mm (2.5 mm HEPES + 50 mm NaCl). Spectrin tetramers were studied only at 4°C whereas the dimers were studied at both 4 °C and 37°C. At 4°C there is
a striking quantitative similarity between the transient electric birefringence (TEB) of spectrin dimers and tetramers. Also,
the TEB of spectrin dimers at 37°C was very similar to the results at 4°C. The contour length and the molecular weight of
spectrin dimers and tetramers are known. The dominating TEB relaxation time is in all cases only a fraction of what is predicted
theoretically if the spectrin dimers and tetramers are assumed to be stiff and extended molecules. In sum, the new TEB data
constitute strong electrooptic evidence confirming that spectrin dimers and tetramers have a highly flexible structure, and
demonstrate for the first time that a major part of the intrachain dynamics of the spectrin is quite insensitive to an increase
of the ionic strength from 4 mm to 53 mm. Use of the reversing electric field pulse technique for all conditions studied yields TEB data suggesting that the orientation
of both spectrin dimers and tetramers in an electric field is dominated by a permanent rather than an induced electric dipole
moment.
Received: 26 August 1998 / Revised version: 8 February 1999 / Accepted: 11 February 1999 相似文献
38.
Martinez-Peña y Valenzuela I Rogers RC Hermann GE Travagli RA 《American journal of physiology. Gastrointestinal and liver physiology》2004,286(2):G333-G339
The dorsal motor nucleus of the vagus (DMV) receives more noradrenergic terminals than any other medullary nucleus; few studies, however, have examined the effects of norepinephrine (NE) on DMV neurons. Using whole cell recordings in thin slices, we determined the effects of NE on identified gastric-projecting DMV neurons. Twenty-five percent of DMV neurons were unresponsive to NE, whereas the remaining 75% responded to NE with either an excitation (49%), an inhibition (26%), or an inhibition followed by an excitation (4%). Antrum/pylorus- and corpus-projecting neurons responded to NE with a similar percentage of excitatory (49 and 59%, respectively) and inhibitory (20% for both groups) responses. A lower percentage of excitatory (37%) and a higher percentage of inhibitory (36%) responses were, however, observed in fundus-projecting neurons. In all groups, pretreatment with prazosin or phenylephrine antagonized or mimicked the NE-induced excitation, respectively. Pretreatment with yohimbine or UK-14304 antagonized or mimicked the NE-induced inhibition, respectively. These data suggest that NE depolarization is mediated by alpha(1)-adrenoceptors, whereas NE hyperpolarization is mediated by alpha(2)-adrenoceptors. In 16 neurons depolarized by NE, amplitude of the action potential afterhyperpolarization (AHP) and its kinetics of decay (tau) were significantly reduced vs. control. No differences were found on the amplitude and tau of AHP in neurons hyperpolarized by NE. Using immunohistochemical techniques, we found that the distribution of tyrosine hydroxylase fibers within the DMV was significantly different within the mediolateral extent of DMV; however, distribution of cells responding to NE did not show a specific pattern of localization. 相似文献
39.
40.
Qiu YL Sekiguchi Y Imachi H Kamagata Y Tseng IC Cheng SS Ohashi A Harada H 《Archives of microbiology》2003,179(4):242-249
An anaerobic, mesophilic, syntrophic benzoate-degrading bacterium, designated strain FB(T), was isolated from methanogenic sludge which had been used to treat wastewater from the manufacture of terephthalic acid. Cells were non-motile gram-positive rods that formed spores. The optimum temperature for growth was 35-40 degrees C, and the optimum pH was 7.0-7.2. A co-culture with the hydrogenotrophic methanogen Methanospirillum hungatei converted benzoate to acetate, carbon dioxide, and methane. Butyrate transiently accumulated at a high concentration of 2.5 mM during degradation. Besides benzoate, no other compound tested supported growth of the co-culture. Crotonate supported growth of strain FB(T) in pure culture. Furthermore, the strain degraded benzoate in pure culture with crotonate as co-substrate to produce acetate and butyrate. The strain was not able to utilize sulfate, sulfite, thiosulfate, nitrate, fumarate, or Fe(III) as electron acceptor. The G+C content of the DNA was 46.8 mol%. Strain FB(T) contained MK-7 as the major quinone and C(16:1) as the major fatty acid. 16S rDNA sequence analysis revealed that the strain was a member of the genus Sporotomaculum, even though it exhibited significant differences, such as the capacity for syntrophic growth, to the known member of the genus. Hence, we propose the name Sporotomaculum syntrophicum sp. nov. for strain FB(T). The type strain is strain FB(T) (DSM 14795, JCM 11475). 相似文献