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Despite its long history, there has been very little systematic study of figure skating. Successful skaters and coaches have passed on ideas, traditions, and opinions to their followers with the idea that what once produced good results must be the correct approach. Skaters are significantly shorter, lighter, and leaner than their sedentary counterparts and have a rather low percent body fat. Their cardiovascular fitness levels are 50% to 60% higher than those of sedentary people of the same age, but far less than those of endurance athletes.  相似文献   
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S Provow  G Veli?elebi 《Endocrinology》1987,120(6):2442-2452
Receptors for vasoactive intestinal peptide (VIP) were characterized in rat lung membranes by binding and covalent cross-linking of [125I]VIP using ethylene glycolbis-(succinimidylsuccinate). Binding studies indicated the presence of two classes of binding sites for VIP in rat lung membranes: 0.28 +/- 0.11 pmol/mg protein high affinity receptors (Kd = 79.2 +/- 26.4 pM) and 3.3 +/- 0.9 pmol/mg protein lower affinity receptors (Kd = 4.8 +/- 2.1 nM). Furthermore, binding of [125I]VIP to rat lung receptors was inhibited by micromolar concentrations of GTP analogs, guanosine-5'-O-(3-thiotriphosphate) GTP gamma S), and guanylylimidodiphosphate, suggesting that VIP receptors in rat lung membranes were tightly coupled to the guanine nucleotide regulatory protein (Ns). Scatchard analysis of VIP binding in the presence of GTP gamma S revealed selective inhibition of binding to high affinity sites. A 58K band was specifically labeled when membranes covalently labeled with [125I]VIP were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reducing conditions. The apparent size of this species was not altered when sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis was carried out in the absence of reducing agent. Unlabeled VIP inhibited the labeling, with an IC50 of about 1 nM. A related peptide, GH-releasing factor-(1-40)OH, exhibited a much lower binding affinity, and two unrelated peptides, insulin and atrial natriuretic factor, did not inhibit labeling of the 58K species, even at micromolar concentrations. Labeling of the 58K species was inhibited in a GTP gamma S-dependent manner, suggesting the involvement of this species in the coupling to Ns. These data collectively indicated that the 58K species was a VIP-binding unit of VIP receptors in rat lung membranes. Several nondenaturing detergents were tested for extraction of labeled receptors from the membrane; the best extraction was obtained using 1% n-octyl-beta-D-glucopyranoside.  相似文献   
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In this multicenter, retrospective study, we evaluated the efficacy and safety of biologic therapies, including anti-TNFs, in secondary (AA) amyloidosis patients with ankylosing spondylitis (AS) and rheumatoid arthritis (RA). In addition, the frequency of secondary amyloidosis in RA and AS patients in a single center was estimated. Fifty-one AS (39M, 12F, mean age: 46.7) and 30 RA patients (11M, 19F, mean age: 51.7) with AA amyloidosis from 16 different centers in Turkey were included. Clinical and demographical features of patients were obtained from medical charts. A composite response index (CRI) to biologic therapy—based on creatinine level, proteinuria and disease activity—was used to evaluate the efficacy of treatment. The mean annual incidence of AA amyloidosis in RA and AS patients was 0.23 and 0.42/1000 patients/year, respectively. The point prevalence in RA and AS groups was 4.59 and 7.58/1000, respectively. In RA group with AA amyloidosis, effective response was obtained in 52.2 % of patients according to CRI. RA patients with RF positivity and more initial disease activity tended to have higher response rates to therapy (p values, 0.069 and 0.056). After biologic therapy (median 17 months), two RA patients died and two developed tuberculosis. In AS group, 45.7 % of patients fulfilled the criteria of good response according to CRI. AS patients with higher CRP levels at the time of AA diagnosis and at the beginning of anti-TNF therapy had higher response rates (p values, 0.011 and 0.017). During follow-up after anti-TNF therapy (median 38 months), one patient died and tuberculosis developed in two patients. Biologic therapy seems to be effective in at least half of RA and AS patients with AA amyloidosis. Tuberculosis was the most important safety concern.  相似文献   
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Cardiogenic shock (CS) is a complex multifactorial clinical syndrome with extremely high mortality, developing as a continuum, and progressing from the initial insult (underlying cause) to the subsequent occurrence of organ failure and death. There is a large spectrum of CS presentations resulting from the interaction between an acute cardiac insult and a patient's underlying cardiac and overall medical condition. Phenotyping patients with CS may have clinical impact on management because classification would support initiation of appropriate therapies. CS management should consider appropriate organization of the health care services, and therapies must be given to the appropriately selected patients, in a timely manner, whilst avoiding iatrogenic harm. Although several consensus‐driven algorithms have been proposed, CS management remains challenging and substantial investments in research and development have not yielded proof of efficacy and safety for most of the therapies tested, and outcome in this condition remains poor. Future studies should consider the identification of the new pathophysiological targets, and high‐quality translational research should facilitate incorporation of more targeted interventions in clinical research protocols, aimed to improve individual patient outcomes. Designing outcome clinical trials in CS remains particularly challenging in this critical and very costly scenario in cardiology, but information from these trials is imperiously needed to better inform the guidelines and clinical practice. The goal of this review is to summarize the current knowledge concerning the definition, epidemiology, underlying causes, pathophysiology and management of CS based on important lessons from clinical trials and registries, with a focus on improving in‐hospital management.  相似文献   
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