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191.
Summary In the guinea-pig uterus, by use of an indirect immunofluorescence method, S-100 immunoreactivity was found to be restricted to nerves that corresponded in number, distribution and type to adrenergic axons and preterminals. With advancing pregnancy S-100 immunoreactivity completely disappeared in uterine tissue adjacent to a fetus, in parallel with an ultrastructural degeneration of the adrenergic innervation. In the cervix and the uterine horn devoid of a fetus, however, the number and distribution of S-100-immunoreactive nerves was seemingly unchanged and no ultrastructural changes were found in adrenergic nerves. In contrast, chemical sympathectomy produced by 6-hydroxydopamine did not change S-100 immunoreactivity of uterine nerves. These findings suggest that there are differences in the denervation effected by chemical and by pregnancy-induced sympathectomy. The latter probably represents a special type of adrenergic denervation by inducing a degeneration of Schwann cells in addition to destruction of neuronal structures. This may explain the differences in the speed of regeneration of uterine adrenergic nerves following the two types of denervation. 相似文献
192.
Osei Yaw Ampomah Seyed Abdollah Mousavi Kristina Lindström Kerstin Huss-Danell 《Systematic and applied microbiology》2017,40(1):51-58
Rhizobia nodulating native Astragalus and Oxytropis spp. in Northern Europe are not well-studied. In this study, we isolated bacteria from nodules of four Astragalus spp. and two Oxytropis spp. from the arctic and subarctic regions of Sweden and Russia. The phylogenetic analyses were performed by using sequences of three housekeeping genes (16S rRNA, rpoB and recA) and two accessory genes (nodC and nifH). The results of our multilocus sequence analysis (MLSA) of the three housekeeping genes tree showed that all the 13 isolates belonged to the genus Mesorhizobium and were positioned in six clades. Our concatenated housekeeping gene tree also suggested that the isolates nodulating Astragalus inopinatus, Astragalus frigidus, Astragalus alpinus ssp. alpinus and Oxytropis revoluta might be designated as four new Mesorhizobium species. The 13 isolates were grouped in three clades in the nodC and nifH trees. 15N analysis suggested that the legumes in association with these isolates were actively fixing nitrogen. 相似文献
193.
Razia H. Ahmed Jaime Nieves Lisa Kim Luis Echegoyen David Puett 《Journal of Protein Chemistry》1987,6(5):431-439
The binding of vanadyl to a porcine and bovine testicular S-100-like protein and to calmodulin was demonstrated using X-band
(9.2 gHz) electron paramagnetic resonance (EPR) spectroscopy in aqueous solution at pH 7.4. In liquid solutions at 22°C, the
vanadyl-protein complexes yielded VO2+ near rigid limit spectra. At 122 K, each of the three high-field resonances (i.e., 3/2, 5/2, and 7/2 parallel components)
splits into two components indicating the presence of two classes of vanadyl-binding sites in each protein. The spectra of
the frozen solutions were simulated to give parallel and perpendicular components of the hyperfine coupling constant and g
factors similar to other vanadyl-protein complexes. 相似文献
194.
195.
The effect of C-protein on the actin-activated ATPase of column-purified skeletal muscle myosin has been investigated at varied ionic strength. At ionic strengths below about 0.1, C-protein is a potent inhibitor. The inhibition is not reversed by increasing the actin concentration, showing that it is caused by C-protein bound to the myosin filaments. When the ionic strength is raised above about 0.12, on the other hand, the inhibition vanishes and C-protein becomes a mild activator of the actomyosin ATPase. Both effects appear rapidly upon addition of C-protein to pre-formed myosin filaments, so C-protein probably acts by binding to the surface of the filaments. 相似文献
196.
We have carried out an electronmicroscopic study of replicas of the underside of culture cells. The techniques developed for the preparation of such replicas are described in detail. We find that the cells do not rest on the surface of the culture dish itself, but rather are attached to a protein film adsorbed from the culture medium. The underside of cells is usually rather smooth looking. It is difficult to clearly define the site of attachment of cells to their substrate. The features interpreted as attachment sites are often bored and diffuse. Heavy bundles of micro-filaments can be recognized in the sole plate of BHK cells. These bundles are usually parallel to the long axes of the cells, and often terminate in cell projections. They are only rarely encountered in the sole plate of transformed BHK cells. 相似文献
197.
瑞拉菌素产生菌S-5120菌株防治黄瓜霜霉病害的研究初报 总被引:6,自引:0,他引:6
经黄瓜霜霉病孢子萌发试验和离体叶片抑菌试验表明,瑞拉菌素产生菌S-5120菌株和瑞拉菌素均对黄瓜霜霉病有较强抑制作用。温室防病试验表明,瑞拉菌素产生菌S-5120发酵液对黄瓜霜霉病有明显的保护和治疗作用。相对保护效果达75.17%;治疗效果达69.69%,且高于农抗-120的相对防效62.65%。 相似文献
198.
中间偃麦草(Thinopyrum intermedium(Host)Barkworth et Dewey)是禾本科小麦族植物中的一个异源六倍体物种,是重要的牧草植物,在小麦的抗病育种中发挥了重要作用.利用荧光原位杂交(FISH)技术,在体细胞中期染色体上,对18S-5.8S-26S rDNA位点进行了物理定位,发现该物种有3~4对染色体携带18S-5.8S-26S rDNA主位点.结合基因组原位杂交(GISH)分析,证明中间偃麦草的St基因组中有一对同源染色体短臂末端携带一个主位点,其余2~3对主位点位于E基因组染色体上.对不同来源的材料研究表明:18S-5.8S-26S rDNA位点的数目(包括主位点和小位点)、位置、拷贝数在不同收集材料之间的差异较大,甚至在同一个体的不同细胞中也存在差异.讨论了rDNA物理作图数据在分析系统发育问题中的局限性.结合中间偃麦草的三个可能的二倍体基因组供体(Th.bessarabicum、Th.elongatum和Pseudoroegneria stipifolia)rDNA位点分析的结果,对中间偃麦草进化过程中rDNA位点的变化进行了分析,同时,对其中一份材料的核ITS序列进行了克隆、测序和系统发育分析,发现在中间偃麦草中,ITS序列具有很高的异质性. 相似文献
199.
Möller R Schüler T Günther S Carlsohn MR Munder T Fritzsche W 《Applied microbiology and biotechnology》2008,77(5):1181-1188
The identification of different Kitasatospora strains has been shown with a DNA-chip based on an electrical readout scheme. The 16S-23S rDNA internal transcribed spacer
region of these Actinomycetes was used for identification. Two different capture probes per strain were immobilized on the chip. The capture probes were
spotted on a DNA-chip with electrode structures for an electrical DNA detection. A biotinylated PCR product of the 16S-23S
rDNA region was incubated on the chips and bound to its complementary capture sequences. Followed by a gold nanoparticle or
enzyme labeling and a deposition of silver, the binding of the PCR product was detected by an increase of the measured conductivity
on the chip. To show the applicability of this detection system, four strains of Kitasatospora were chosen for an identification using the DNA-chip with electrical detection. Each strain was clearly identified using
the system. Concentrations of the polymerase chain reaction (PCR) products within the range of 1 ng/ml to 1 μg/ml were detected
and identified. These tests are the first application of this novel electrical detection scheme for the identification and
classification of microorganisms. The presented results show that the DNA-chip with electrical detection can be used for a
robust and cost-efficient DNA analysis. 相似文献
200.
Using an experimental model of postoperation hyperalgesia (incision of the tissues on the foot) on 45 mongrel Wistar rats, we demonstrated that postoperation hyperalgesia (24 h after surgical intervention) is accompanied by a rise in the concentration of astroglial proteins (glial fibrillary acidic protein, GFAP, and S-100 protein) in the medulla oblongata and thalamus/hypothalamus. An agonist of NMDA receptors, glutamate (1 mg/kg), injected 5 min prior to the surgical procedure caused a greater increase in the concentration of astroglial proteins, whereas a noncompetitive antagonist of the above receptors, MK-801 (0.5 mg/kg), injected according to the same protocol to a great extent prevented postoperation hyperalgesia-related changes in the level of astroglial proteins in the thalamus/hypothalamus and medulla oblongata. Our findings show that astroglia actively influences glutamate-mediated neurotransmission, which plays a leading role in the development of postoperation hyperalgesia. 相似文献