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WINOCOUR PH; KALUVYA S; BROWN L; FARRER M; MILLAR JP; NEIL HAW; ALBERTI KGMM 《QJM : monthly journal of the Association of Physicians》1991,79(3):539-560
Hyperinsulinaemia is said to be a risk factor for cardiovasculardisease, but the extent to which different insulinaemic measuresare associated with vascular risk factors in ostensibly healthyindividuals, and whether they operate independently in men andwomen, remains uncertain. The association between risk factors and various insulinaemicmeasures was examined in 148 men and 118 women who were normoglycaemic,normotensive, and non-obese (body mass index in men <27,in women <25). A 75 g glucose tolerance test was administeredafter blood sampling for fibrinogen, lipids, lipoproteins andinsulin. Insulin was also measured after 1 and 2 hours. Significantunivariate correlations (p<0.01) were most consistently recordedbetween insulinaemic measures and fasting serum triglyceridesin men and women, whilst systolic blood pressure only correlatedwith insulinaemia in women, and diastolic blood pressure correlatedwith fasting and 2 hour insulinaemic measures in men and women.Inconsistent associations were noted with total serum cholesterolin men and women, with high density lipoprotein cholesterol,body mass index, apoprotein B and A1 in men, and with fibrinogenin women. Age was not correlated with any insulinaemic measurein men or women. Differences in vascular risk factors between quintiles of theinsulinaemic measures were examined, after correction for bodymass index. The dominant association with fasting and post-glucoseload insulinaemic measures was with triglycerides, especiallyin women, with less frequent graded differences between quintilesobserved for total cholesterol, and diastolic and systolic bloodpressures in men and women. The incidence of other risk factors often only differed in thelowest or highest quintile in comparison to other quintiles,suggesting a threshold rather than a graded effect. Furthermore,differences in HDL cholesterol and apoprotein B were only recordedfor top quintiles of post-glucose challenge/integrated insulinaemicmeasures in men, whilst serum fibrinogen concentrations onlydiffered significantly in women in the top insulinaemic areaunder the curve quintile. In the absence of additional risk factors such as diabetes,hypertension and obesity, insulinaemic measures are not consistentlyrelated to blood pressure and measures of lipid metabolism andcoagulation, and are thus a weak predictor of other cardiovascularrisk factors. The vascular risk profile associated with insulinappears somewhat different in apparently healthy men and women. 相似文献
23.
Limited-field-of-view radio-frequency receiver antennas provide improved near-field sensitivity for magnetic resonance imaging by decreasing the antenna volume. The Helmholtz-type surface coil, consisting of two flat rings, is an organ-encompassing antenna that takes advantage of this principle to yield an improved signal-to-noise ratio (S/N). The coil was tested in a group of 50 patients and 16 healthy volunteers. Images obtained with the Helmholtz coil demonstrated quantitatively superior S/N of 2.2-fold or greater than that of comparison body coil images, as well as qualitatively superior anatomic resolution. 相似文献
24.
Ernst?Kiesswetter M.?Sch?per M.?Buchta K.?H.?Schaller B.?Rossbach T.?Kraus S.?Letzel 《International archives of occupational and environmental health》2009,82(10):1191-1210
Objectives
This is the second of two parallel longitudinal studies investigating Al exposure and neurobehavioral health of Al welders over 4 years. While the first published study in the trail and truck construction industry examined the neurobehavioral development of Al welders from age 41–45 in the group mean (Kiesswetter et al. in Int Arch Occup Environ Health 81:41–67, 2007), the present study in the automobile industry followed the development from 35 to 39. Although no conspicuous neurobehavioral developments were detected in the first study, which furthermore exhibited the higher exposure, it cannot be excluded that exposure effects appear in earlier life and exposure stages. 相似文献25.
26.
Summary For many years percutaneous needle and classic burr-hole trephination with insertion of plastic catheters for external ventricular drainage are in use. The shortcomings of the conventional puncture needles were compensated for by the development of a modified instrument in recent years.In this prospective study we tried to define advantages and disadvantages of percutaneous ventriculostomy with this modified needle in a large number of patients. We treated and followed a total number of 200 patients with external ventricular drainage for various reasons (42% obstructive hydrocephalus, 27% haematocephalus, 11% malresorptive hydrocephalus, 11% elevated ICP and 9% infections). The ventriculostomy is performed — after percutaneous trepheication with a 1.5 mm drill and 1.2 mm needle under the local aesthesia as a bedside procedure. The modified blunt needle is provided with markings and a set screw which allows insertion to a prefixed depth and a sharp guide which is withdrawn after penetration of the dura. It is then bent rostrally and fixed by a plaster cast. The mean duration of drainage was 9 days (1–30 days). Mean operating time for the whole procedure including fixation and connection to the drainage system was 20 minutes. Overall complication rate was 13% (N=26). Two intracerebral haemorrhages (1%) occurred, of which one was caused by overdrainage. Five (3%) infections in primarily not infectious cases (N=182) were seen. Only one case of infection occurred without loosing of the needle on day 17. In 19 patients (10%) the needles had loosened. Fifteen times this complication was repaired in time and no infection occurred. The overall complication rate (13%) and the needle related risk of bleeding (0.5%) seem average. The true risk of infection with correct handling (0.5%) is very low despite the very long average duration of drainage. The main risk lies in the markedly high danger of loosening (10%), which entails a disproportionally high demand for nursing care. Nevertheless, we regard percutaneous needle trephination as the ventriculostomy method of choice because of its better practicability and low infection rate. 相似文献
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28.
Summary. The expression of adhesion molecules on human spermatozoa of healthy probands was analysed. The localization patterns of adhesion molecules (AM) on the spermatozoal surface were documented by fluorescence microscopy. Spermatozoa were incubated with antibodies against α1 (CD49a), α2 (CD49b), α3 (CD49c), α4 (CD49d), α5 (CD49e), α6 (CD49f) chains of β1 integrins, β1 (CD29), β2 (CD18), αV (CD51), β3 (CD61) and β4 integrin chains, the LFA-3 (Lymphocyte function antigen, CD58) from the immunoglobulin superfamily and the extracellular matrix proteins laminin, fibronectin and collagen IV. For collagen IV, α1 and α2 chains no expression could be noticed. Laminin was detected at the acrosomal membrane, fibronectin and β4 chain mainly at the equatorial membrane. The fibronectin receptors α3, α4 and α5 chains of the β1 integrins were mainly located on acrosomal and equatorial membrane areas. Laminin receptor α6 chain was located postacrosomal and less frequently acrosomal. β2 chain and vitronectin receptors αV and β3 chains had a mainly postacrosomal localization pattern. LFA-3 was found constantly on postacrosomal membrane areas. Double staining technique was used to prove the simultaneous occurrence of fibronectin and its integrin receptors α3, α4 and α5 chains and of αV and β2 chains on spermatozoa. The localization patterns of integrins on double stained spermatozoa were similar to the patterns described for single stained spermatozoa. The localization of fibronectin appeared to be influenced by the presence of integrins: the typical equatorial fibronectin band disappeared in case of an equatorial localization of integrins. 相似文献
29.
30.
K. Kerschenlohr U. C. Schaller E.M. Messmer A. Wollenberg 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》2003,100(3):240-251
Lidekzeme sind pathogenetisch heterogen. Ihre Behandlung ist durch die anatomischen und funktionellen Gegebenheiten der Periorbitalregion
erschwert. Dies macht sie, neben ihrer h?ufigen Therapieresistenz und Rezidivneigung, zu einer gro?en diagnostischen und therapeutischen
Herausforderung für Haut- und Augen?rzte.Auch ein vergleichsweise kleinfl?chiges Lidekzem kann aufgrund der belastenden Symptomatik
und der hohen ?sthetischen Bedeutung dieser K?rperregion einen hohen Leidensdruck verursachen. Diese interdisziplin?re übersichtsarbeit
zum Thema behandelt vor allem aktuelle pathogenetische und therapeutische Aspekte der Lidekzeme.
Dr.A.Wollenberg Klinik und Poliklinik für Dermatologie und Allergologie der Ludwig-Maximilians-Universit?t München, Frauenlobstr.9-11, 80337
München, E-Mail: wollenberg@lrz.uni-muenchen.de 相似文献