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891.
892.
A placebo-controlled, comparative clinical study was conducted to test the hypothesis that nicotinic acid as an adjuvant medication has a beneficial therapeutic effect over and above the effect which can be achieved by the administration of phenothiazine drugs alone, over a six-month period, in newly (recently) admitted schizophrenic patients.The most important single finding was that no statistically significant therapeutic difference was seen between the active treatment and the placebo groups; i.e., the addition of nicotinic acid or nicotinamide to the regular phenothiazine treatment regimen did not have any measurable therapeutic effect in this sample of patients. It was shown that patients in the placebo group received a lower total daily amount of phenothiazine drugs than those on either of the active substances. Furthermore, it was noted that the addition of the active substances did not reduce the number of days of hospitalization. 相似文献
893.
894.
Amjad A. Mahasneh Jazi D. Odat Ban M. Al-Joubori Ismail Saadoun 《Saudi Journal of Biological Sciences》2021,28(8):4500-4510
This investigation aimed to determine the relatedness of dominant occurring soil Streptomyces spp. in Northern Jordan based on their RAPD-PCR fingerprints, and to compare RAPD technique with the conventional phenotypic characterization of Streptomyces isolates. Fifty-eight white and gray color-bearing aerial mycelia antibiotic active-producing Streptomyces soil isolates along with three reference strains were genetically analyzed by RAPD-PCR. Polymorphisms between the isolates showed 1 to 10 bands per isolate and ranged from 200 to 3200 bp in size. Results revealed one common band of ~600 bp shared by ~85% of the isolates, and the observation of bands specific to some reference strains and some soil isolates. When RAPD patterns were analyzed with the UPGMA, results revealed clustering the tested isolates into two equal main super clusters (50% each). Super cluster I appeared to be homogenous and include the three reference strains. However, super cluster II was heterogeneous and but not including any of the reference strains. The association of the antibiotic activity of the dominant white and gray aerial mycelium-bearing Streptomyces isolates to RAPD clustering is reported for the first time, and the RAPD-PCR fingerprints generated here deserve to be cloned, characterized and sequenced in future as Streptomyces species-specific DNA markers. The more random primers used in the analysis may add to RAPD technique a cost-effective, fast, precise result, and less labor work solution for analyzing the similarities and differences among the Streptomyces isolates. 相似文献
895.
Hiromi Mutsuura Kenji Kanbara Mikihiko Fukunaga Kazumi Yamamoto Ikumi Ban Kana Kitamura Yoshihide Nakai 《Applied psychophysiology and biofeedback》2009,34(4):291-298
Patients presenting with functional somatic syndrome (FSS) are common, and the symptoms are persistent and difficult to treat
for doctors and costly for society. The aim of this study was to clarify the common pathophysiology of FSS, especially the
relationship between hypothalamic-pituitary-adrenal (HPA) axis function and psychological characteristics of patients with
FSS. The subjects were 45 patients with FSS and 29 healthy controls. Salivary free cortisol was measured in the morning, and
psychological tests examining depression, anxiety and quality of life (QOL) were performed on the same day. In patients with
FSS, depressive scores showed a significant negative correlation with salivary free cortisol in the morning, although in healthy
controls, cortisol showed a significant positive correlation with depressive scores. In addition, the correlation between
other psychological test scores and cortisol secretion in patients with FSS contrasted with that of controls. The relationship
between cortisol and depression, anxiety or QOL, suggests that the HPA axis of patients with FSS is dysfunctional and does
not function properly when patients with FSS are under stress. This dysfunction may explain the pathology of medically unexplained
persistent symptoms of patients with FSS. 相似文献
896.
897.
Wang Minqin Zhao Junsheng Peng Zhenying Guo Wei Wang Yun Wang Le Xia Guangmin 《Plant Cell, Tissue and Organ Culture》2008,92(2):121-130
In order to investigate chromosome elimination in symmetric somatic hybridization between Bupleurum scorzonerifolium and Arabidopsis thaliana, protoplasts were isolated from suspension cultures of both A. thaliana and B. scorzonerifolium parents. Biparental protoplasts were mixed at a rate of 1.5:1 and fused with PEG-method. After protoplast fusion, the products
were cultured in the P5 liquid medium for microcallus formation. Single cell lines formed from microcalli after subculturing
on the MB1 (Xia and Chen, Plant Sci 120:197–203, 1996) solid medium. The putative somatic hybrid cell lines were identified
by cytological and molecular analysis. Of the 132 somatic cell lines generated, 16 were identified as somatic hybrids, with
the phenotypes resembled B. scorzonerifolium parent. These hybrids showed a complete set of B. scorzonerifolium chromosome and 0–2 small chromosome(s) of A. thaliana. A few of them showed nuclear and cytoplasmic SSR fragments of A. thaliana. These hybrid cell lines could differentiate to green spots, buds/leaves through complementation of regeneration ability.
The chromosomes elimination of A. thaliana was discussed.
Wang Minqin and Zhao Junsheng contributed equally to the work. 相似文献
898.
Takeshi Onuma Mikihiko Higa Hironori Ando Masatoshi Ban Akihisa Urano 《Developmental neurobiology》2005,63(2):126-145
Our previous studies suggested that salmon gonadotropin‐releasing hormone (sGnRH) neurons regulate both final maturation and migratory behavior in homing salmonids. Activation of sGnRH neurons can occur during upstream migration. We therefore examined expression of genes encoding the precursors of sGnRH, sGnRH‐I, and sGnRH‐II, in discrete forebrain loci of prespawning chum salmon, Oncorhynchus keta. Fish were captured from 1997 through 1999 along their homing pathway: coastal areas, a midway of the river, 4 km downstream of the natal hatchery, and the hatchery. Amounts of sGnRH mRNAs in fresh frozen sections including the olfactory bulb (OB), terminal nerve (TN), ventral telencephalon (VT), nucleus preopticus parvocellularis anterioris (PPa), and nucleus preopticus magnocellularis (PM) were determined by quantitative real‐time polymerase chain reactions. The amounts of sGnRH‐II mRNA were higher than those of sGnRH‐I mRNA, while they showed similar changes during upstream migration. In the OB and TN, the amounts of sGnRH mRNAs elevated from the coast to the natal hatchery. In the VT and PPa, they elevated along with the progress of final maturation. Such elevation was also observed in the rostroventral, middle, and dorsocaudal parts of the PM. The amounts of gonadotropin IIβ and somatolactin mRNAs in the pituitary also increased consistently with the elevation of gene expression for sGnRH. These results, in combination with lines of previous evidence, indicate that sGnRH neurons are activated in almost all the forebrain loci during the last phases of spawning migration, resulting in coordination of final gonadal maturation and migratory behavior to the spawning ground. © 2005 Wiley Periodicals, Inc. J Neurobiol, 2005 相似文献
899.
Xiaofang Yang Xiaoling Zhao Zhengyan Dai Feilong Ma Xuexia Miao Zhenying Shi 《Plant physiology》2021,186(1):519
microRNAs (miRNAs) are promising targets for crop improvement of complex agricultural traits. Coordinated activity between/among different miRNAs may fine-tune specific developmental processes in diverse organisms. Grain size is a main factor determining rice (Oryza sativa L.) crop yield, but the network of miRNAs influencing this trait remains uncharacterized. Here we show that sequestering OsmiR396 through target mimicry (MIM396) can substantially increase grain size in several japonica and indica rice subspecies and in plants with excessive tillers and a high panicle density. Thus, OsmiR396 has a major role related to the regulation of rice grain size. The grain shape of Growth Regulating Factor8 (OsGRF8)-overexpressing transgenic plants was most similar to that of MIM396 plants, suggesting OsGRF8 is a major mediator of OsmiR396 in grain size regulation. A miRNA microarray analysis revealed changes to the expression of many miRNAs, including OsmiR408, in the MIM396 plants. Analyses of gene expression patterns and functions indicated OsmiR408 is an embryo-specific miRNA that positively regulates grain size. Silencing OsmiR408 expression (miR408KO) using CRISPR technology resulted in small grains. Moreover, we revealed the direct regulatory effects of OsGRF8 on OsMIR408 expression. A genetic analysis further showed that the large-grain phenotype of MIM396 plants could be complemented by miR408KO. Also, several hormone signaling pathways might be involved in the OsmiR396/GRF-meditated grain size regulation. Our findings suggest that genetic regulatory networks comprising various miRNAs, such as OsmiR396 and OsmiR408, may be crucial for controlling rice grain size. Furthermore, the OsmiR396/GRF module may be important for breeding new high-yielding rice varieties.The OsmiR396/Growth Regulating Factor module plays a pivotal role in rice grain size regulation and genetically regulates OsmiR408, which acts as an embryo-specific grain size regulator. 相似文献