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71.
Weinkove, D., Poyatos, J. A., Greiner, H., Oltra, E., Avalos, J., Fukshansky, L., Barrero, A. F., and Cerdá-Olmedo, E. 1998. Mutants ofPhycomyceswith decreased gallic acid content.Fungal Genetics and Biology25, 196–203. Most plants and some fungi accumulate phenols. Two hydroxybenzoic acids, gallic and protocatechuic acids, are abundant in the giant sporangiophores of the zygomycetePhycomyces blakesleeanus,much more so than in the basal mycelium or the culture medium. The actual concentrations vary with illumination, age of the culture, and composition of the medium. We devised a simple screening procedure to isolatehbamutants whose sporangiophores contained less gallic acid than the wild type. The most useful mutant had very low concentrations of hydroxybenzoic acids in the sporangiophores, but about the same as the wild type in the basal mycelium and the medium. The mutant was only slightly different from the wild type in growth and morphology. Mutant and wild-type sporangiophores grew away from ultraviolet C sources (260 nm) equally well. Contrary to previous conjectures, ultraviolet tropism does not depend on the ultraviolet absorption of gallic acid or other free hydroxybenzoic acids in the sporangiophore. Against expectations, phenols did not impair DNA extraction: sporangiophores produced better DNA preparations than basal mycelia and thehbamutant only slightly better than the wild type.  相似文献   
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This review is focused on the epidemiology of venous thromboembolism (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE), associated with pregnancy. Superficial vein thrombosis, a less hazardous and less studied type of thrombosis in pregnant women, is beyond the scope of this review. This study discusses the VTE incidence rate in women from developed countries for both antepartum and postpartum periods and for subpopulations of women affected by additional risk factors, such as thrombophilias, circulatory diseases, preeclampsia of varying degrees of severity, and Caesarean section. To minimize bias due to historical changes in medical and obstetric practices, lifestyle, diet, etc., this review is generally limited to relatively recent studies, i.e., those that cover the last 35 years. The absolute risk or incidence rate was used to ascertain risk of VTE associated with pregnancy. For the studies where the direct incidence rates of VTE were not reported, we calculated an estimate of the observed but not reported absolute incidence rates using the data presented in respective articles. Birth Defects Research (Part C) 105:167–184, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
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BackgroundStereotactic body radiation therapy (SBRT) as a form of noninvasive treatment that is becoming increasingly used to manage cancers with adrenal gland metastases. There is a paucity of data on safety and efficacy of this modality. The aim of the study was to evaluate the safety and efficacy of adrenal gland SBRT in oligometastatic and oligoprogressive disease.Materials and methodsIn this retrospective study, we performed a single-institution analysis of 26 adrenal lesions from 23 patients with oligometastatic or oligoprogressive disease treated from 2013 to 2019 with the goal of achieving durable local control. Palliative cases were excluded. Radiation dosimetry data was collected. Kaplan Meier product estimator and Cox proportional hazards regression analysis were used for statistical analysis.ResultsThe median dose was 36 Gy in 3 fractions (range: 24–50 Gy and 3–6 fractions) with a median biologically effective dose (BED10) of 72 (range: 40–100). 1-year local control rate was 80% and median local control was not achieved due to a low number of failures. 1- and 2-year overall survival rates were 66% and 32%. Toxicity was mild with only one case of grade 2 nausea and no grade 3–5 toxicity. Higher neutrophil to lymphocyte ratio was associated with worse overall survival and a trend toward worse progression-free survival. In addition, worse performance status and lower BED10 were associated with worse survival. No such association could be shown for primary tumor location, histology, size or stage.ConclusionAdrenal SBRT for oligometastatic or oligoprogressive disease is a safe and effective form of treatment.  相似文献   
75.
Shade light found in ecological niches where plants are growing under a canopy or in proximity of taller neighbouring vegetation consist mainly of two separate light signals: low red to far-red ratio and low photosynthetically active radiation (PAR). The effect of the latter on the growth of 7-day old sunflower shoots was examined by assessing hypocotyl, cotyledon and leaf tissue growth under three varying PAR levels: near-normal of 1,000 μmol m?2 s?1, low of 100 μmol m?2 s?1 and very low of 10 μmol m?2 s?1. Then, the possible interaction between PAR signaling and ethylene in regulating growth of these sunflower tissues was investigated. The results showed that gradual decrease in PAR level increases hypocotyl elongation and decreases ethylene evolution. However, gradual decrease in PAR level decreases cotyledon and leaf growth and increases ethylene evolution. Thus it seems possible that PAR regulation of shoot growth is mediated by changes in ethylene evolution in tissue specific manner. This hypothesis was supported by experiments with the ethylene releasing factor, ethephon, and the ethylene biosynthesis inhibitor, AVG, as well as by transfer experiments where sunflower seedlings were transferred from one PAR regime to another with subsequent growth and ethylene measurements.  相似文献   
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Background  

Pancreatic beta-cells respond to rising blood glucose by increasing oxidative metabolism, leading to an increased ATP/ADP ratio in the cytoplasm. This leads to a closure of KATP channels, depolarization of the plasma membrane, influx of calcium and the eventual secretion of insulin. Such mechanism suggests that beta-cell metabolism should have a functional regulation specific to secretion, as opposed to coupling to contraction. The goal of this work is to uncover contributions of the cytoplasmic and mitochondrial processes in this secretory coupling mechanism using mathematical modeling in a systems biology approach.  相似文献   
78.
The effective new variant of "sandwich" bioluminescent enzyme immunoassay (BEIA) for the sensitive detection of glycoprotein B (gB) of pseudorabies virus (PrV) was presently developed. The high affinity interaction of barnase-barstar protein pair and photoprotein obelin as bioluminescent marker were for the first time successfully applied to BEIA development. Preliminary the two monoclonal antibodies, 11/5 and 34/2, were raised against gB for ELISA PrV detection. Presently we used the same immuno-"sandwich" principle for BEIA. To do this the two different bioconjugates were elaborated. Recombinant barnase was chemically conjugated with monoclonal anti-PrV's gB IgG, and also barstar was fused in frame to obelin. The characteristics of BEIA method have been compared to ELISA PrV detection. We have shown the proposed here gB-BEIA was 40-fold more sensitive as opposed to gB-ELISA test. The construction might have a broad promise in multiple potential immunological applications.  相似文献   
79.
The role of gap junctions in endothelium-derived hyperpolarizing factor (EDHF)-mediated relaxation of human arteries was assessed using connexin mimetic peptides (CMPs) designated (37,43)Gap27, (40)Gap27, and (43)Gap26 according to homology with the major vascular connexins (Cx37, Cx40, and Cx43). Resistance arteries were obtained from subcutaneous fat biopsies of healthy pregnant women undergoing elective cesarean section. Endothelium-dependent vasodilatation to bradykinin (BK) was assessed using wire myography. N(omega)-nitro-l-arginine methyl ester (l-NAME) and indomethacin (nitric oxide synthase and cyclooxygenase inhibitors, respectively) attenuated maximal relaxation to BK (R(max)) by approximately 50%. Coincubation with l-NAME, indomethacin, and the combined CMPs ((37,43)Gap27, (40)Gap27, and (43)Gap26) almost abolished relaxation to BK (R(max) = 12.2 +/- 3.7%). In arteries incubated with l-NAME and indomethacin, the addition of either (37,43)Gap27 or (40)Gap27 had no significant effect on R(max), whereas (43)Gap26 caused marked inhibition (R(max) = 21 +/- 6.4%, P = 0.005 vs. l-NAME plus indomethacin alone) that was similar to that of the triple combination. Endothelium-independent vasorelaxation was unaffected by CMPs, l-NAME, or indomethacin. Immunohistochemistry demonstrated Cx37, Cx40, and Cx43 expression in the endothelium and vascular smooth muscle. In pregnant women, EDHF-mediated vasorelaxation of subcutaneous resistance arteries is dependent on Cx43 and gap junctions.  相似文献   
80.
A Gram-positive, aerobic, rod-shaped, nonmotile, endospore-forming bacterium, designated Gsoil 349T, was isolated from soil of a ginseng field and characterized using a polyphasic approach. Comparative analysis of 16S rRNA gene sequences revealed that the strain Gsoil 349T belongs to the family Paenibacillaceae, and the sequence showed closest similarity with Cohnella thermotolerans DSM 17683T (94.1%) and Cohnella hongkongensis DSM 17642T (93.6%). The strain showed less than 91.3% 16S rRNA gene sequence similarity with Paenibacillus species. In addition, the presence of MK-7 as the major menaquinone and anteiso-C(15:0), iso-C(16:0), and C(16:0) as major fatty acids suggested its affiliation to the genus Cohnella. The G+C content of the genomic DNA was 53.4 mol%. On the basis of its phenotypic characteristics and phylogenetic distinctiveness, strain Gsoil 349T should be treated as a novel species within the genus Cohnella for which the name Cohnella panacarvi sp. nov. is proposed. The type strain is Gsoil 349T (=KCTC 13060T = DSM 18696T).  相似文献   
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