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11.
南疆棉区棉花品种的特性演变与育种潜力研究   总被引:2,自引:0,他引:2  
南疆棉区经过5次大的品种更换,高产品种的选育起了非常重要的作用,新育成的品种比早期育成的品种产量以每年12.1kg/hm2的速度增长,品种改良对产量的贡献率为43.9%。衣分、单株结铃数和单铃重的总的演变趋势是增加的,农艺性状方面株高降底,株宽增加,自育品种的现蕾量较低,脱落率较高,南疆棉花品种的综合品质变化不大,特别是棉花生产品质未发生根本性变化。南疆棉花品种在单株结铃数、衣分、增加现蕾数、降低花蕾脱落、株宽、果枝始节、高光合速率品种的选育以及纤维比强度等方面具备较大的选择潜力。  相似文献   
12.
Renal cell carcinomas (RCC) are emerging as a complex set of diseases that are having a major socioeconomic impact and showing a continued rise in incidence throughout the world. As the field of urologic oncology faces these trends, several major genomic and mechanistic discoveries are altering our core understanding of this multitude of cancers, including several new rare subtypes of renal cancers. In this review, these new findings are examined and placed in the context of the well-established association of clear cell RCC (ccRCC) with mutations in the von Hippel-Lindau (VHL) gene and resultant aberrant hypoxia inducible factor (HIF) signaling. The impact of novel ccRCC-associated genetic lesions on chromatin remodeling and epigenetic regulation is explored. The effects of VHL mutation on primary ciliary function, extracellular matrix homeostasis, and tumor metabolism are discussed. Studies of VHL proteostasis, with the goal of harnessing the proteostatic machinery to refunctionalize mutant VHL, are reviewed. Translational efforts using molecular tools to elucidate discriminating features of ccRCC tumors and develop improved prognostic and predictive algorithms are presented, and new therapeutics arising from the earliest molecular discoveries in ccRCC are summarized. By creating an integrated review of the key genomic and molecular biological disease characteristics of ccRCC and placing these data in the context of the evolving therapeutic landscape, we intend to facilitate interaction among basic, translational, and clinical researchers involved in the treatment of this devastating disease, and accelerate progress toward its ultimate eradication.  相似文献   
13.
The adipocyte-type fatty acid-binding protein (A-FABP) is considered a candidate gene for fat metabolism; thus, it affects fat deposition in chickens. The present study was designed to examine the polymorphism and mRNA abundance of the A-FABP gene with intramuscular fat (IMF) in the pectoralis muscles (PM) and leg muscles (LM) of Three-yellow Chicken (TYC) and Hetian-black Chicken (HTBC). In total, 60 TYCs and 60 HTBCs were sacrificed using exsanguination at market age. The IMF contents of the PM and LM in the HTBC were significantly higher than those in the TYC. Three genotypes of the A-FABP gene first exon, AA, AB, and BB, were examined by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP), and a C51 T mutational site, which is a silent substitution mutation, was revealed. The IMF contents of the AA genotype in the PM of the HTBC were significantly higher than those in the AB genotype; thus, the C51 T mutable site is a gene marker for selecting a higher IMF content in the PM of the HTBC. The relative expression of the A-FABP mRNA in the LM of the HTBC, which was measured by quantitative real-time PCR, was significantly higher than in the TYC. A significantly positive association was detected between A-FABP expression with the IMF contents of the PM and LM of both the TYC and the HTBC. These results provide basic data that might be helpful to further research the role of the A-FABP gene in fat deposition and fatty acid metabolism in chickens.  相似文献   
14.
15.
Generalized peeling skin syndrome (PSS) is an autosomal recessive genodermatosis characterized by lifelong, continuous shedding of the upper epidermis. Using whole-genome homozygozity mapping and whole-exome sequencing, we identified a novel homozygous missense mutation (c.229C>T, R77W) within the CHST8 gene, in a large consanguineous family with non-inflammatory PSS type A. CHST8 encodes a Golgi transmembrane N-acetylgalactosamine-4-O-sulfotransferase (GalNAc4-ST1), which we show by immunofluorescence staining to be expressed throughout normal epidermis. A colorimetric assay for total sulfated glycosaminoglycan (GAG) quantification, comparing human keratinocytes (CCD1106 KERTr) expressing wild type and mutant recombinant GalNAc4-ST1, revealed decreased levels of total sulfated GAGs in cells expressing mutant GalNAc4-ST1, suggesting loss of function. Western blotting revealed lower expression levels of mutant recombinant GalNAc4-ST1 compared to wild type, suggesting that accelerated degradation may result in loss of function, leading to PSS type A. This is the first report describing a mutation as the cause of PSS type A.  相似文献   
16.
Hereditary leukonychia (porcelain nails or white nails) is a rare nail disorder with an unknown genetic basis. To identify variants in a gene underlying this phenotype, we identified four families of Pakistani origin showing features of hereditary leukonychia. All 20 nails of each affected individual were chalky and white in appearance, consistent with total leukonychia, with no other cutaneous, appendageal, or systemic findings. By using Affymetrix 10K chip, we established linkage to chromosome 3p21.3-p22 with a LOD score (Z) of 5.1. We identified pathogenic mutations in PLCD1 in all four families, which encodes phosphoinositide-specific phospholipase C delta 1 subunit, a key enzyme in phosphoinositide metabolism. We then identified localization of PLCD1 in the nail matrix. It was recently shown that PLCD1 is a component of the human nail plate by proteomic analysis and is localized in the matrix of human nails. Furthermore, mutations detected in PLCD1 resulted in reduced enzymatic activity in vitro. Our data show that mutations in PLCD1 underlie hereditary leukonychia, revealing a gene involved in molecular control of nail growth.  相似文献   
17.
The use of an ET-1 fluorescent probe in human heart and vascular smooth muscle cells showed that ET-1 receptors are present at both the sarcolemma and nuclear envelope membranes. The use of immunofluorescence studies showed that the ETA receptor was mainly present at the sarcolemma and cytosolic levels. However, the ETB receptor was present at the sarcolemma and the cytosol, as well as the nuclear envelope membranes and the nucleoplasm. In addition, ET-1 immunoreactivity was seen in the cytosol and the nucleus. Using Ca2+ fluorescent probes such as Fluo-3, Indo 1, and yellow cameleon, as well as confocal microscopy three-dimensional image measurement technique, stimulation of ET-1 receptors at the sarcolemma membranes induced an increase of cytosolic and nuclear free Ca2+ levels. This effect of extracellular ET-1 was blocked by removal of extracellular calcium. Direct stimulation of ET-1 receptors at the nuclear envelope membranes also induced an increase of intranuclear free Ca2+ level. Our results suggest that the stimulation of sarcolemmal Ca2+ influx by ET-1 seems to be due to the activation of ETA and ETB receptors. However, the increase of nucleoplasmic Ca2+ levels by cytosolic ET-1 seems to be mediated via the activation of ETB receptors. Activation of nuclear membranes ETB receptors seems to prevent nuclear Ca2+ overload and may protect the cell from apoptosis.  相似文献   
18.
585 nm for the treatment of port-wine stains   总被引:2,自引:0,他引:2  
Although the flashlamp-pulsed-dye laser has been successfully used for the treatment of port-wine stains (PWS) at 577 nm, a number of adult patients had incomplete clearance of their birthmarks with this treatment modality because of residual vessels lying beyond the 0.75-mm penetration depth of 577-nm irradiation. Fifteen adult patients, of whom nine were previously treated with limited success at 577 nm (group A), and six untreated patients (group B) were included in the study. For the group A patients, treatment with 585 nm produced successful clearance of the birthmark. For the six patients in group B, parallel treatment of different sites of the same lesion coupled with skin biopsies and histologic examination revealed that a change in the wavelength from 577 to 585 nm allowed the laser light to penetrate from the midreticular dermis into the subcutaneous fat. This explained the clearance achieved at 585 nm and not at 577 nm.  相似文献   
19.
In this study, CuLaSe2 and ZnCuLaSe2 quantum dots (QDs) with a mean size of ~4 nm were synthesized and characterized, and their temperature-dependent photoluminescence (PL) properties were studied in the temperature range from 90 to 300 K for the first time. The results show that the obtained QDs were spherical and revealed excitonic band gaps. The PL intensity for both types of materials decreased when increasing the temperature to 300 K, which was attributed to the nonradiative relaxation and thermal escape mechanisms. As the temperature was increased, the PL linewidths broadened, and PL peak energies were red shifted for both types of QDs due to the exciton–phonon coupling and lattice deformation potential mechanisms. In addition, we found that as the temperature was decreased, the PL spectrum of ZnCuLaSe2 QDs contained two extra components, which could be attributed to the shallow defect sites (low energy peak) and the crystal phase transition process (high energy peak). The spectrum of CuLaSe2 QDs contained one extra component, which could be attributed to the crystal phase transition process.  相似文献   
20.
Degenerate oligodeoxyribonucleotide (oligo) primers derived from amino acid (aa) sequence motifs held in common between all members of the protein tyrosine kinase (PTK) family were used to prime the amplification of PTK-related sequences from a variety of murine cDNA sources, including the haemopoietic cell lines, FDC-P1 and WEHI-3B D+, peritoneal macrophages and whole brain. Several parameters, such as the length (short, i.e., less than 20 nucleotides (nt) vs. long, i.e., greater than 30 nt) and degeneracy (i.e., moderately degenerate vs. highly degenerate) of the oligo primers and the temperature of the extension phase of the reaction, were examined. The data from these analyses suggest that the most effective type of primer in this application of the polymerase chain reaction is a short, moderately degenerate oligo such as that which might be derived from the small patches of aa sequence homology that are frequently found to be held in common among members of protein families. In addition to a number of previously described PTK sequences, a novel mammalian PTK-related sequence was uncovered.  相似文献   
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