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181.
Zhou HL Yang HJ Li YM Wang Y Yan L Guo XL Ba YC Liu S Wang TH 《Neurochemical research》2008,33(5):927-937
Limited information is available regarding the role of endogenous Glial cell line-derived neurotrophic factor (GDNF) in the
spinal cord following transection injury. The present study investigated the possible role of GDNF in injured spinal cords
following transection injury (T9–T10) in adult rats. The locomotor function recovery of animals by the BBB (Basso, Beattie, Bresnahan) scale score showed that
hindlimb support and stepping function increased gradually from 7 days post operation (dpo) to 21 dpo. However, the locomotion
function in the hindlimbs decreased effectively in GDNF-antibody treated rats. GDNF immunoreactivty in neurons in the ventral
horn of the rostral stump was stained strongly at 3 and 7 dpo, and in the caudal stump at 14 dpo, while immunostaining in
astrocytes was also seen at all time-points after transection injury. Western blot showed that the level of GDNF protein underwent
a rapid decrease at 7 dpo in both stumps, and was followed by a partial recovery at a later time-point, when compared with
the sham-operated group. GDNF mRNA-positive signals were detected in neurons of the ventral horn, especially in lamina IX.
No regenerative fibers from corticospinal tract can be seen in the caudal segment near the injury site using BDA tracing technique.
No somatosensory evoked potentials (SEP) could be recorded throughout the experimental period as well. These findings suggested
that intrinsic GDNF in the spinal cord could play an essential role in neuroplasticity. The mechanism may be that GDNF is
involved in the regulation of local circuitry in transected spinal cords of adult rats. 相似文献
182.
Plants used as natural dye sources in Turkey 总被引:1,自引:0,他引:1
This study was carried out in the regions where handcrafts such as carpet and rug weaving are common in Turkey. In the regions
where natural dyes are used, 123 plant species belonging to 50 families were identified as sources of natural dyes. In natural
dye production, different parts of the plant or the whole aboveground plant is used. Ten different colors are gained from
the plants. Sometimes the same color can be obtained from different plants. By mixing different plants, it is possible to
produce various colors. We also identified more than 12 natural and more than eight chemical assistant substances (mordant)
that are used in the regions to bind dye to fibers, to maintain the strongness and brightness of the colors, and to obtain
various colors 相似文献
183.
Samba K Marc Bouvy Seyni San Ngansoumana Ba Robert Arfi Omar Thiom Thiaw Marc Pagano 《International Review of Hydrobiology》2011,96(4):405-424
Seasonal variations of zooplankton communities and their interactions with phytoplankton and environmental parameters were studied over a twelve‐month period in Lake Guiers (Senegal, West Africa). Zooplankton was most abundant during the warm and rainy season corresponding to the flood event (July to October) with peaks for rotifers and cyclopoid copepods in July–August and September–October, respectively. Filamentous cyanobacteria were the dominant phytoplankton during the warm season (August to November), while diatoms were dominant during the cool season (December to April). Temperature increase and river flooding both played an important role in these successions, favoring intense development of cyanobacteria and cyclopoid copepods. Trophic interactions also seem to be an important factor in structuring of the plankton community. Overall, the plankton composition displayed a trend toward a eutrophication state. Our study confirms the existence of seasonality in zooplankton communities and the importance of using biological indicators such as phyto‐ and zooplankton to monitor water quality, in particular in tropical freshwater ecosystems. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
184.
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186.
I M Ba?bekov V M Vorozhe?kin Sh N Artykov 《Biulleten' eksperimental'no? biologii i meditsiny》1992,113(4):424-427
With the aid of light, electron transmission and scanning electron microscopy and radioautography and stereometry, the influence of low-intensive laser irradiation (LILI) (infrared) was studied in normal rat liver and in experimental cirrhosis and hepatitis. It was revealed that arsenide-gallium laser irradiation causes the change of intracellular structure. These changes show the intensification on their specific function manifest in an increase of relative volume of intracellular structures. The changes of microvessels show the activation of microcirculation. The elevation of the index of the labelled nuclei testify to increased proliferation. The similar influences of LILI on the liver ultrastructure and proliferation in hepatitis and cirrhosis are accompanied by the reduction of the pathological changes of the liver--the hepatocytes oedema, granular, vacuolar and fatty dystrophy. 相似文献
187.
Translocation induction in mouse spermatogonia by continuous whole-body gamma irradiation (radium 226) was studied. Total doses, delivered at a rate of 13.0 +/- 1.3 X 10(-4) rad/min for various time intervals, were 97, 195, 294 and 442 rad. Cytological examination within 3 to 4 months after irradiation indicated the presence of translocations in 0.16, 0.30, 0.75 and 1.29 percent respectively, of primary spermatocytes at diakinesis metaphase I. Data on translocation induction (Y) as related to total irradiation dose (D) were best fitted to a second power parabola equation (Y=5.1 X 10(-6)D2 + 7.32 X 10(-4) X D). The results obtained confirm that chronic gamma irradiation is of low genetic efficiency, and support the suggestion that there exists a dose-rate threshold under which no more changes in exposure efficiency will occur. 相似文献
188.
189.
M S Ba?zhomartov I Kh Shuratov V A Semenova G U Diuskalieva O G Stetsenko 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1985,(2):68-72
The dynamics and nature of serum antibodies in experimental and natural M. pneumoniae infection have been studied. The synthesis of specific IgM, IgA and IgG has been found to occur in the course of infection. During repeated M. pneumoniae infection in guinea pigs, as well as in cases of acute and chronic mycoplasmal pneumonia in humans (at the acute period of the disease), the prevalence of the synthesis of specific IgM is observed. At the acute period of the disease a rise in the quantitative levels of IgM and IgG occurs in patients. High titers of specific IgM (1:32 and greater) determined at the acute period of the disease can serve as the diagnostic criterion of the mycoplasmal etiology of pneumonia. 相似文献