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51.
Thor S. Trovik Aase Vaartun Georg Sager 《Basic & clinical pharmacology & toxicology》1995,77(4):270-275
Abstract: Loss of adrenergic hypoglycaemic symptoms is the most distinctive feature in insulin-dependent diabetes mellitus (IDDM) patients with hypoglycaemia unawareness. Previous reports from in vivo studies show reduced heart rate responsiveness both to adrenergic agonists and antagonists in these patients. This study was carried out to investigate whether the reduced adrenergic sensitivity in IDDM patients with hypoglycaemia unawareness (IDDM-unaware) also could be demonstrated as reduced increase in cAMP production in mononuclear leucocytes induced by isoprenaline stimulation, or reduced inhibition by ICI-118551 (a selective β2-adrenergic receptor blocker) of isoprenaline induced cAMP production. We found that the slope of the concentration-response curves of isoprenaline/cAMP and the maximal cAMP concentrations obtained after isoprenaline stimulation were reduced in IDDM-unaware compared to control and IDDM patients with normal hypoglycaemia awareness (IDDM-aware). We did not find any significant differences in the response to ICI-118551 between control, IDDM-aware and IDDM-unaware. This study supports the reports of reduced sensitivity of adrenergic agonists as a part of the pathophysiological changes in hypoglycaemia unawareness, but we have not been able to confirm the reports of an association between hypoglycaemia unawareness and reduced effect of adrenergic antagonists. 相似文献
52.
Michael B Leahy Johannes T Dessens Friedemann Weber Georg Kochs Patricia A Nuttall 《Virus research》1997,50(2):215-224
The tick-borne Thogoto virus (THOV) is the type species of a newly recognized fourth genus, Thogotovirus, in the family Orthomyxoviridae. Because of the distant relationship of THOV with the influenza viruses, determination of its genomic information can potentially be used to identify important domains in influenza virus proteins. We have determined the complete nucleotide sequence of the second longest RNA segment of THOV. The molecule comprises 2212 nucleotides with a single large open reading frame encoding a protein of 710 amino acids, estimated Mr 81 284. The protein shares 77% amino acid similarity with the PB1-like protein of Dhori virus, a related tick-borne virus, and 50–53% with the PB1 polymerase proteins of influenza virus A, B and C. All the motifs characteristic of RNA-dependent polymerases were identified including the SSDD motif common to all RNA-dependant RNA polymerases, indicating that the THOV protein is functionally analogous to the influenza virus PB1 proteins and involved in chain elongation. We also report the corrected sequence of the third longest RNA segment of THOV, encoding a protein which shares 44–47% amino acid similarity with the PA-like polymerase proteins of influenza virus A, B and C. The biological significance of conserved domains in these orthomyxovirid proteins is discussed. 相似文献
53.
54.
Hoschek Stefan Hoschek-Risslegger Ursula Fiegl Michael Zabernigg August Pall Georg Auberger Thomas Gunsilius Eberhard Schmid Thomas Jamnig Herbert Hilbe Wolfgang 《Wiener Medizinische Wochenschrift》2007,157(21):562-568
Wiener Medizinische Wochenschrift - Aggressives Tumorwachstum, frühe Metastasierung und hohe Assoziation mit intensivem Nikotinkonsum sind die Charakteristika des kleinzelligen... 相似文献
55.
In 2003 the International Headache Society (IHS) published the second edition of the International Classification of Headache Disorders. Diagnostic criteria for no less than 206 separate headache diagnoses are presented in the parts (I) primary headaches, (II) secondary headaches and (III) cranial neuralgia, central and primary facial pain. The headaches are classified according to the etiology in case of the secondary headaches and according to the phenomenology in case of the primary headaches. It is the task of the headache specialist to identify the correct headache diagnose with the smallest effort possible. Both, the differentiation between secondary and primary headaches and the differentiation between the various primary headaches are of equal importance. 相似文献
56.
57.
In the not-so-distant past the skin was generally viewed as a passive target for immune-mediated injury. Over the last decade, however, concepts of a previously unrecognized role for the skin have unfolded, whereby resident bone marrow-derived leukocytes (e.g. Langerhans cells and T cells) initiate and regulate the immune responses that protect it. Their combination with other immunomodulatory resident cells (e.g. keratinocytes, melanocytes, endothelial cells, fibroblasts) led to the idea that the skin may function as a self-sustaining lymphoid tissue. Although T lymphocytes or, at least, certain subpopulations thereof have the general propensity to populate epithelial tissues, there exist major species differences regarding the phenotype of intraepidermal T cells. The purpose of this review is to fill gaps in our understanding of the relationship of rodent skin T cells to T cells identified in human skin and the normal physiologic and pathologic role(s) of these cells. 相似文献
58.
Josef Georg Heckmann Tamara Fischer Ruben Maida Juan Carlos Jesus Galeote 《Zeitschrift fur Gesundheitswissenschaften》1998,6(2):166-177
The Chiquitano-tribe lives in the southern Amazonas region in Bolivia, remote from larger towns. A study (n=1514) on morbidity over an one year period (April 1995 till March 1996) and its relation to general and social medicine is given. Most frequently, childreh under 15 years and women in parity age (15–45 years) sought consultation (34,1 %, 42,7 %). Gastrointestinal, respiratoral and gynecological-obstetric diseases were predominant (22,4 %, 16,2 % and 15,7 %). In the dry season, common colds and respiratoral infections represented the major health problem. In the rainy season, infectious diarrhea diseases caused by polluted water as a consequence of extended floods were most frequent. Typical tropical diseases (malaria, Dengue fever, Chagas’ disease, leprosy a.o.) and socially caused diseases (AIDS, dependencies on drugs and alcohol, consequencies of crime) were rarely seen. With respect to severity, 55,8 % of the patients showed mild disorders. More serious diseases were observed in 39, 8 %. 4,6 % of the patients were diagnosed severly ill and needed hospitalization. Epidemiological data on general and social medicine of minorities in developing countries and their actual degree of medical care are important in a shrinking world. The data are useful to estimate medical needs and plan improvements to the health care system especially in rural areas. 相似文献
59.
Rapid chemical kinetic techniques for investigations of
neurotransmitter receptors expressed
in Xenopus oocytes
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Li Niu RaymondW. Vazquez Georg Nagel Thomas Friedrich Ernst Bamberg RobertE. Oswald GeorgeP. Hess 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(23):12964-12968
Xenopus laevis oocytes have been used extensively during the past decade to express and study neurotransmitter receptors of various origins and subunit composition and also to express and study receptors altered by site-specific mutations. Interpretations of the effects of structural differences on receptor mechanisms were, however, hampered by a lack of rapid chemical reaction techniques suitable for use with oocytes. Here we describe flow and photolysis techniques, with 2-ms and 100-μs time resolution, respectively, for studying neurotransmitter receptors in giant (≈20-μm diameter) patches of oocyte membranes, using muscle and neuronal acetylcholine receptors as examples. With these techniques, we find that the muscle receptor in BC3H1 cells and the same receptor expressed in oocytes have comparable kinetic properties. This finding is in contrast to previous studies and raises questions regarding the interpretations of the many studies of receptors expressed in oocytes in which an insufficient time resolution was available. The results obtained indicate that the rapid reaction techniques described here, in conjunction with the oocyte expression system, will be useful in answering many outstanding questions regarding the structure and function of diverse neurotransmitter receptors. 相似文献
60.
Cotinine determination by immunoassays may be influenced by other nicotine metabolites 总被引:1,自引:0,他引:1
Polyclonal rabbit anticotinine antiserum, which can be used for biomonitoring nicotine uptake by the determination of cotinine in body fluids, was checked by a competitive ELISA for its cross-reactivity with nine nicotine metabolites. The highest percentage of relative crossreactivity (about 30%) was observed with trans-3-hydroxycotinine, a metabolite which is known to be excreted in 3-fold higher amounts than cotinine in the urine of human smokers. Therefore, it is possible that cotinine determinations performed by immunochemical methods — especially in urine — may yield overestimated cotinine concentrations. 相似文献