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81.
82.
The performance of a major quantitative trait locus (QTL) of terminal drought tolerance (DT) of pearl millet was assessed under salt stress. The test-cross hybrids of the QTL donor parent (drought tolerant, PRLT 2/89-33), QTL recipient parent (drought sensitive, H 77/833-2), and a set of six near isogenic lines introgressed with a terminal DT-QTL (QTL-NILs) were evaluated for germination and seedling emergence at 7 days after sowing (DAS) in Petri plates at four salinity levels, and at vegetative (24 DAS) and maturity stages at three salinity and alkalinity levels. Na+ and K+ accumulation, their compartmentation in different plant parts, and their effects on growth and yield parameters were evaluated. The DT-QTL donor parent and QTL-NILs accumulated less Na+ in shoot parts at seedling, vegetative and maturity stages, and also partitioned the accumulated Na+ more into nodes and internodes and less into leaves than the drought-sensitive recurrent parent. The pattern of reduced salt accumulation in the drought-tolerant parent and QTL-NILs was consistently associated with better growth and productivity in saline and alkaline treatments. It is concluded that the DT-QTL contributed by PRLT 2/89-33 exerted favourable effects on growth and productivity traits under salt stress by limiting Na+ accumulation in leaves.  相似文献   
83.
84.
On association in a copula with time transformations   总被引:2,自引:0,他引:2  
Fine  JP; Jiang  H 《Biometrika》2000,87(3):559-571
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85.
BackgroundThere is sparse literature on whether training in endobronchial ultrasound (EBUS)-guided transbronchial needle aspiration (TBNA) improves the diagnostic yield of conventional TBNA (cTBNA).ObjectivesThe aim of this study was to evaluate the diagnostic yield of cTBNA before and after the introduction of EBUS.MethodsThis was a retrospective analysis of patients who underwent cTBNA at our center. The study was divided into two periods, before and after the introduction of EBUS at our facility. The diagnostic yield of cTBNA was compared between the study periods. Rapid on-site cytological examination was not available.ResultsA total of 1,050 patients (61.6% men; mean age 45.6 years) underwent cTBNA during the study period (849 before EBUS; 201 after EBUS). Sarcoidosis (n = 527) followed by bronchogenic carcinoma (n = 222) formed the most common indications for performing cTBNA. There was a significant increase in both the success of obtaining a representative sample (from 71% to 85%), and the diagnostic yield (from 33% to 49.5%) of cTBNA, after the introduction of EBUS. The increase in the diagnostic yield of cTBNA after introduction of EBUS remained significant even after adjusting for years of performing cTBNA and the type of anesthesia (topical vs. sedation and topical) on a multivariate analysis.ConclusionThe diagnostic yield of cTBNA at our facility increased after the introduction of EBUS-TBNA. However, given the retrospective nature of the study, prospective studies are required to confirm our findings.  相似文献   
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Changes in intracellular free Ca2+ concentration [( Ca2+]i) were used to study the interaction between mitogens in Swiss 3T3 fibroblasts. Platelet-derived growth factor (PDGF) produced an increase in [Ca2+]i and markedly decreased the increases in [Ca2+]i caused by subsequent addition of bradykinin and vasopressin. If the order of the additions was reversed the [Ca2+]i response to PDGF was not inhibited by bradykinin or vasopressin. Inhibition of protein kinase C by staurosporine or chronic treatment of the cells with phorbol 12-myristate 13-acetate prevented the inhibitory effect of PDGF on the [Ca2+]i response to vasopressin but not bradykinin. PDGF did not decrease the receptor binding of bradykinin and produced only a small decrease in the receptor binding of vasopressin. PDGF decreased the rise in [Ca2+]i caused by the Ca2+ ionophores 4-bromo-A23187 and ionomycin and by a membrane perturbing ether lipid, 1-octadecyl-2-methyl-rac-glycero-3-phosphocholine, both in the presence and absence of external Ca2+. There was no change in cell 45Ca2+ influx caused by PDGF, vasopressin, or bradykinin. 45Ca2+ efflux from cells exposed to PDGF and vasopressin mirrored the changes in [Ca2+]i caused by the agents, that is, PDGF added after vasopressin produced a further increase in 45Ca2+ efflux but vasopressin did not increase 45Ca2+ efflux after PDGF. PDGF but not vasopressin caused an increase in the uptake of 45Ca2+ into an inositol 1,4,5-trisphosphate-insensitive non-mitochondrial store in permeabilized cells. The results suggest that the decreased [Ca2+]i response to mitogens after PDGF represents an action of PDGF at a point beyond the release of intracellular Ca2+ and the influx of external Ca2+, caused by an increase in the rate of removal of cytoplasmic free Ca2+. This increased removal of cytoplasmic Ca2+ by PDGF is not due to the increased export of Ca2+ from the cell but results from increased Ca2+ uptake into non-mitochondrial stores.  相似文献   
88.
The rate at which triploid grass carp, Ctenopharyngodon idella , consumed two plant species from different locations was measured and compared to the chemical composition of the plants. Grass carp fed on Elodea canadensis from three lakes at significantly different rates ( P > 0.001), but did not eat Elodea densa from two of the sites at different rates. Feeding rate of the grass carp was positively correlated to the concentration of calcium ( r = 0.976) and lignin ( r = 0.946), but negatively correlated to the content of iron ( r =−0.808), silica (r=-0.934) and cellulose ( r =−0.922). Multiple regression analysis revealed that calcium and cellulose content were the most important predictors of consumption rate. These experiments demonstrate that water chemistry may affect palatability and could in part be responsible for some of the discrepancies in grass carp consumption rate and preference studies.  相似文献   
89.
IgG antibody to M. tuberculosis antigen-5 was detected by non-competitive ELISA in cerebrospinal fluid specimens (CSF), from 40 patients with clinical diagnosis of tuberculous meningitis and in 42 patients of non-tuberculous neurological diseases. The geometric mean antibody titer in CSF specimen for tuberculous and non-tuberculous groups were 156 and 8 respectively. The antibody titer in CSF specimens showed no correlation to IgG levels, tuberculin reactor status and duration of chemotherapy in patients with tuberculous meningitis. At a dilution end-point 1:40, the assay had a sensitivity of 84% and specificity of 92%. However at dilution end-point 1:80, the specificity of the assay could be increased to 100% but sensitivity of the assay decreased to 75%. IgG antibody detection against M. tuberculosis antigen-5 by non-competitive ELISA, described in this communication has potential application in the laboratory diagnosis of tuberculous meningitis, particularly in developing countries where the incidence and prevalence of tuberculous meningitis is still high. In culture-negative cases of tuberculous meningitis, non-competitive ELISA could be applied as an alternative diagnostic tool.  相似文献   
90.
Simian immunodeficiency virus from African green monkeys.   总被引:24,自引:14,他引:10       下载免费PDF全文
Simian immunodeficiency virus (SIV) was isolated from the total peripheral blood mononuclear cell population and the monocyte-macrophage adherent cell population of three seropositive green monkeys originating from Kenya. SIV from these African green monkeys (SIVagm) was isolated and continuously produced with the MOLT-4 clone 8 (M4C18) cell line but not with a variety of other cells including HUT-78, H9, CEM, MT-4, U937, and uncloned MOLT-4 cells. Once isolated, these SIVagm isolates were found to replicate efficiently in M4C18, SupT1, MT-4, U937, and Jurkat-T cells but much less efficiently if at all in HUT-78, H9, CEM, and MOLT-4 cells. The range of CD4+ cells fully permissive for replication of these SIVagm isolates thus differs markedly from that of previous SIV isolates from macaques (SIVmac). These SIVagm isolates had a morphogenesis and morphology like that of human immunodeficiency virus (HIV) and other SIV isolates. Antigens of SIVagm and SIVmac cross-reacted by comparative enzyme-linked immunosorbent assay only with reduced efficiency, and optimal results were obtained when homologous antibody and antigen were used. Western blotting (immunoblotting) of purified preparations of SIVagm isolate 385 (SIVagm385) revealed major viral proteins of 120, 27, and 16 kilodaltons (kDa). The presumed major core protein of 27 kDa cross-reacted antigenically with the corresponding proteins of SIVmac (28 kDa) and HIV-1 (24 kDa) by Western blotting. Hirt supernatant replicative-intermediate DNA prepared from cells freshly infected with SIVagm hybridized to SIVmac and HIV-2 DNA probes. Detection of cross-hybridizing DNA sequences, however, required very low stringency, and the restriction endonuclease fragmentation patterns of SIVagm were not similar to those of SIVmac and HIV-2. The nucleotide sequence of a portion of the pol gene of SIVagm385 revealed amino acid identities of 65% with SIVmac142, 64% with HIV-2ROD, and 56% with HIV-1BRU; SIVagm385 is thus related to but distinct from previously described primate lentiviruses SIVmac, HIV-1, and HIV-2. Precise information on the genetic makeup of these and other SIV isolates will possibly lead to better understanding of the history and evolution of these viruses and may provide insight into the origin of viruses that cause acquired immunodeficiency syndrome in humans.  相似文献   
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