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471.
Dr. Heiner Birkenbeil 《Cell and tissue research》1983,229(2):433-441
Summary The formation and secretion of ecdysteroid by the prothoracic gland cells of Galleria mellonella (Insecta, Lepidoptera) were investigated electron microscopically and immunocytochemically. The moulting hormone ecdysone becomes first evident in vesicles and tubules of the smooth endoplasmic reticulum (SER). The SER forms secretory granules in which ecdysone was shown immunocytochemically. The Golgi apparatus seems not to be directly involved in ecdysone secretion. The secretory granules are released from the cells by exocytosis.Supported by the Sächsische Akademie der Wissenschaften zu LeipzigThe author is grateful to Mrs. Angelika Schmidt for her excellent assistance 相似文献
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473.
B B Rosenblum L G Lee S L Spurgeon S H Khan S M Menchen C R Heiner S M Chen 《Nucleic acids research》1997,25(22):4500-4504
We have used two new dye sets for automated dye-labeled terminator DNA sequencing. One set consists of four, 4,7-dichlororhodamine dyes (d-rhodamines). The second set consists of energy-transfer dyes that use the 5-carboxy-d-rhodamine dyes as acceptor dyes and the 5- or 6-carboxy isomers of 4'-aminomethylfluorescein as the donor dye. Both dye sets utilize a new linker between the dye and the nucleotide, and both provide more even peak heights in terminator sequencing than the dye-terminators consisting of unsubstituted rhodamine dyes. The unsubstituted rhodamine terminators produced electropherograms in which weak G peaks are observed after A peaks and occasionally C peaks. The number of weak G peaks has been reduced or eliminated with the new dye terminators. The general improvement in peak evenness improves accuracy for the automated base-calling software. The improved signal-to-noise ratio of the energy-transfer dye-labeled terminators combined with more even peak heights results in successful sequencing of high molecular weight DNA templates such as bacterial artificial chromosome DNA. 相似文献
474.
Gary Wedemeyer 《Journal of bacteriology》1969,100(1):542-543
Endotoxins from Escherichia coli and Aeromonas salmonicida caused marked cortisol production in the rainbow trout (Salmo gairdneri). 相似文献
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Maria Narres Heiner Claessen Sigrid Droste Tatjana Kvitkina Michael Koch Oliver Kuss Andrea Icks 《PloS one》2016,11(1)
End-stage renal disease (ESRD) in diabetes is a life threatening complication resulting in a poor prognosis for patients as well as high medical costs. The aims of this systematic review were (1) to evaluate the incidence of ESRD due to all causes and due to diabetic nephropathy in the diabetic population and differences between incidences of ESRD with respect to sex, ethnicity, age and regions, (2) to compare incidence rates in the diabetic and non-diabetic population, and (3) to investigate time trends. The systematic review was conducted according to the PRISMA group guidelines by performing systematic literature searches in the biomedical databases until January 3rd 2015; thirty-two studies were included. Among patients with incident type 1 diabetes the 30-year cumulative incidence ranged from 3.3% to 7.8%. Among patients with prevalent diabetes, incidence rates of ESRD due to all causes ranged from 132.0 to 167.0 per 100,000 person-years, whereas incidence rates of ESRD due to diabetic nephropathy varied from 38.4 to 804.0 per 100,000 person-years. The incidence of ESRD in the diabetic population was higher compared to the non-diabetic population, and relative risks varied from 6.2 in the white population to 62.0 among Native Americans. The results regarding time trends were inconsistent. The review conducted demonstrates the considerable variation of incidences of ESRD among the diabetic population. Consistent findings included an excess risk when comparing the diabetic to the non-diabetic population and ethnic differences. We recommend that newly designed studies should use standardized methods for the determination of ESRD and population at risk. 相似文献
478.
Hans‐Heiner Bergmann 《当今生物学》2016,46(6):384-387
The terrestrial birds of La Graciosa The small island La Graciosa is part of an archipelago north of Lanzarote, the northern‐ and easternmost of the Canary Islands. Its habitats are mainly semi‐desert made up of sand dunes covered with dry shrubbery. They house only a small number of terrestrial birds, among them endemic species and subspecies of the Canary Islands. Birds are more common around the settlement of Caleta del Sebo where fresh water and more plant species are available. 相似文献
479.
DNA methylation and mRNA expression of developmentally important genes in bovine oocytes collected from donors of different age categories
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480.
Birgit Harbeck Sven Danneberg Amir-Hossein Rahvar Christian S. Haas Hendrik Lehnert Peter Kropp Heiner Mönig 《Applied psychophysiology and biofeedback》2016,41(3):341-347
Hydrocortisone (HC) substitution is essential in the treatment for patients with adrenal insufficiency (AI). Current replacement regimens however only incompletely mimic the physiological circadian rhythm of cortisol secretion, thereby resulting in subclinical temporary hypo- and hypercortisolism. Several studies point toward impairment of cognitive functions under these conditions, in part due to affected catecholamine secretion. Aim of this study was to evaluate the influence of long-term versus short-term HC replacement therapy on the adrenomedullary system and cognitive functions. Fourteen patients with primary or secondary AI were divided into two groups, depending on the duration of disease and HC replacement therapy (<15 years). All subjects underwent standardized neurocognitive testing; in addition, cortisol and catecholamine levels as well as physiological parameters and quality of life (QoL) were assessed. Patients with HC replacement therapy ≥15 years (n = 7) received significantly higher equivalent glucocorticoid doses than those with a shorter lasting therapy (n = 7; p = 0.048). Neuropsychological tests, QoL, physiological parameters, and cortisol levels did not differ significantly between both groups. Of note, norepinephrine levels were significantly lower in patients on short-term HC replacement therapy (p = 0.025). However, there were no significant differences in catecholamines with respect to the underlying pathophysiology, gender, or age. Irrespective of the duration of use, male patients scored significantly better for single aspects of QoL, whereas females performed significantly better in the attention test. Overall, we showed that duration of cortisol replacement therapy may have an impact on catecholamine release, but does not seem to affect cognitive functions and QoL. 相似文献