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21.
This consensus paper on behalf of the Study Group on Sports Cardiology of the European Society of Cardiology follows a previous one on guidelines for sports participation in competitive and recreational athletes with supraventricular arrhythmias and pacemakers. The question of imminent life-threatening arrhythmias is especially relevant when some form of ventricular rhythm disorder is documented, or when the patient is diagnosed to have inherited a pro-arrhythmogenic disorder. Frequent ventricular premature beats or nonsustained ventricular tachycardia may be a hallmark of underlying pathology and increased risk. Their finding should prompt a thorough cardiac evaluation, including both imaging modalities and electrophysiological techniques. This should allow distinguishing idiopathic rhythm disorders from underlying disease that carries a more ominous prognosis. Recommendations on sports participation in inherited arrhythmogenic conditions and asymptomatic gene carriers are also discussed: congenital and acquired long QT syndrome, short QT syndrome, Brugada syndrome, catecholaminergic polymorphic ventricular tachycardia, arrhythmogenic right ventricular cardiomyopathy and other familial electrical disease of unknown origin. If an implantable cardioverter defibrillator is indicated, it is no substitute for the guidelines relating to the underlying pathology. Moreover, some particular recommendations for patients/athletes with an implantable cardioverter defibrillator are to be observed.  相似文献   
22.
One case of a double-time, bilateral spontaneous fracture of the femoral neck as a result of a hepatogenic osteopathy is reported. The other reasons for spontaneous fractures are shortly mentioned, the osteopathy in chronic liver disease is examined more closely.  相似文献   
23.
In this study we assessed the influence of patient- and drug-specific parameters in the short-term MTT-chemosensitivity assay in 150 primary cell cultures derived from human brain tumors. In 45 patients the MTT assay was directly compared with the CFA (Colony Forming Assay). Resistance was 10-20% higher in the MTT assay than in the CFA, but there was a good agreement in both assays, that more malignant gliomas had a higher in vitro chemosensitivity against ACNU and BCNU. Overall the results demonstrate, that there is no uniform correlation between the in vitro chemosensitivity and the histopathological classification of the tumors, which corresponds well to the clinical situation. On the basis of this study we suggest prospective clinical trials with the MTT assay in human brain tumors.  相似文献   
24.
A PTH gene has been isolated from the fish Fugu rubripes. The encoded protein of 80 amino acid has the lowest homology with any of the PTH family members. Fugu PTH(1-34) had 5-fold lower potency than human PTH(1-34) in a mammalian cell system. INTRODUCTION: Parathyroid hormone (PTH) is the major hypercalcemic hormone in higher vertebrates. Fish lack parathyroid glands, but there have numerous attempts to identify and isolate PTH from fish. MATERIALS AND METHODS: Polymerase chain reaction (PCR) was performed with primers based on preliminary data from the Joint Genome Institute database. PCR amplification was performed on genomic DNA isolated from Fugu rubripes. PCR products were purified and DNA was sequenced. All sequence was confirmed from more than one independently amplified PCR product. Multiple sequence alignments were carried out, and the percentage of identities and similarities were calculated. An unrooted phylogenetic tree, using all the known PTH and PTH-related protein (PTHrP) amino acid sequences, was determined. Synthetic peptides were tested in a biological assay that measured cyclic adenosine 3',5'-monophosphate formation in UMR106.1 cells. Rabbit polyclonal antisera specific for N-terminal human PTHrP and one rabbit polyclonal antiserum specific for N terminus hPTH were used to test the cross-reactivity with fPTH(1-34) in immunoblots.  相似文献   
25.
Rapamune (Sirolimus), the latest immunosuppressant agent for solid organ transplants, is prescribed for induction therapy, refractory rejection, steroid withdrawal, and combination therapy. As the use of this agent increases among various transplant populations, it is essential for critical care nurses to be cognizant of the indications, pharmacodynamics, current research findings, side effects, and implications. This knowledge will ultimately improve patient education and outcomes in this ever-growing field of nursing.  相似文献   
26.
While thrombosis prevention is routine in traumatology and orthopaedics departments, there is some controversy over whether it should be applied in outpatients. New clinical studies have shown that a trauma or an operation is followed by a period during which the risk of thrombosis is extremely high. So far no standardized models are available for determining the necessity for temporary prophylactic treatment to avoid thrombosis, and publications on the incidence of deep leg vein thrombosis during ambulatory treatment have presented widely deviating views. More recent studies show a difference between expositional risks and dispositional risks. In this article, evidential data, recent literature and the latest communications issued by specialist societies are used as a basis for presentation of the indications for such ambulatory treatment and guidelines on its maximum duration.  相似文献   
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OBJECTIVES--To examine internal exposure and targeted health outcomes of employees exposed to 3-(3,5-dichlorophenyl)-5-methyl-5-vinyl-1,3-oxazolidine-2,4-dione; chemical abstracts service (CAS) number: 50471-44-8 (vinclozolin). METHODS--A cross sectional study of 67 men exposed to vinclozolin for one to 13 years during synthesis and formulation operations and 52 controls. Biomonitoring was based on determination of urinary metabolites that contained a 3,5-dichloroaniline (3,5-DCA) moiety. Targeted health endpoints were the same as in previous subchronic and chronic animal studies--namely, reversible changes in the concentrations of hormones of the adrenocorticotrophic and gonadotrophic feedback systems, signs of liver injury, haemolytic anaemia, cataract formation (uniquely in rats), and hormonally induced hyperplasia and tumours at high doses. The clinical investigation consisted of a medical and occupational history questionnaire, physical examination, laboratory determinations (including testosterone, LH, and FSH measurements), ultrasonography of the liver and prostate, a detailed eye examination, and routine spirometry. RESULTS--The mean 3,5-DCA concentration for two thirds of the study group exceeded an equivalent of the vinclozolin acceptable daily intake (ADI) used for consumer regulatory purposes. Even the highest concentrations were, however, at least 10 times below the no observable adverse effect level (NOAEL) based on animal studies. Analysis of physical examination and laboratory data provided no evidence of hormonal responses induced by vinclozolin. Furthermore, no evidence of liver injury, prostate changes, cataract formation, or haemolytic anaemia was found. CONCLUSION--There was no evidence of any health effects induced by vinclozolin among employees with potential long term exposure. In particular, no antiandrogenic effects were found.  相似文献   
29.
Alterations of blood flow contribute to major clinical complications in invasive infections such as sepsis and bacterial meningitis. As a unique feature streptococci -- in particular, Streptococcus pneumoniae, the most frequent pathogen in bacterial meningitis -- release hydrogen peroxide (H(2)O(2)) because of the absence of functional catalase. In a 6 h rat model of experimental meningitis, we studied the impact of bacterial H(2)O(2) production on regional cerebral blood flow (rCBF) and intracranial pressure (ICP). Compared to wild-type D39 pneumococci, the increase of rCBF was diminished in meningitis induced by the H(2)O(2) defective SpxB(-) mutant (maximum increase, 135% +/- 17% versus 217% +/- 23% of the individual baseline; P<0.01) or after treatment of D39-induced meningitis with H(2)O(2)-degrading catalase or with tetraethylammonium (TEA), a blocker of calcium-sensitive potassium channels, which mediate H(2)O(2)-induced vasodilation. Catalase did not significantly reduce the remaining rCBF increase caused by SpxB(-), supporting the predominant role of bacterial H(2)O(2). We conclude that in addition to host-sided mediators, bacterial-derived H(2)O(2) acts as a potent vasodilator, which accounts for a certain proportion of the early cerebral hyperperfusion in pneumococcal meningitis.  相似文献   
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