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21.
Background: diabetic patients with end-stage renal
failure (ESRD) have a high cardiovascular morbidity and mortality. The
underlying mechanisms are not completely elucidated. The aim of our study
was to define predictors of death in diabetic patients with end-stage renal
disease. Patients and methods: We preformed a
prospective study in 35 dialysis centres in Germany between 1985 and 1994.
To evaluate predictors and risk factors in this population we examined 412
diabetic patients at the time of admission to dialysis treatment
(peritoneal dialysis (PD) or haemodialysis (HD)). Classification of the
type of diabetes was done according the criteria of the National Diabetes
Data Group [1,2]. Items assessed at the time of admission were coronary
artery disease (CAD), peripheral occlusive disease (POD), and stroke. CAD
was defined as a history of myocardial infarction with the corresponding
changes in the ECG or luminal narrowing by more than 50% in at least one
coronary artery upon coronarangiography; POD was defined as claudication
and/or brachial-tibial ratio (BTR) less than 0.9 or a history of
amputation. Assessment of the nutritional state comprised body mass index,
skinfold thickness of the upper arm and lateral thorax area, and urea
concentration. Cholesterol, HDL, LDL, apolipoprotein A (ApoA-I) and B
(ApoB), triglycerides, lipoprotein (a) (Lp(a)), and fibrinogen were
measured. As an index of disturbed cardiac innervation beat-to-beat
variation was measured. Outcome measurements were causes of death (i.e.
cardiac and non-cardiac) and time of survival.
Results: One hundred and eighty of 412 (44%) patients
died during the observation period Patients who died were older
(61±12 versus 53±15 years P
lt;0.0001), had lower skin fold thickness (13.1±6.0
versus 15.1±7.2 mm P <0.04), lower
ApoA-I (100±35 versus 111±32
mg/dl P <0.005) and higher fibrinogen (515±156
versus 451±155 mg/dl P <0.02). Type
II diabetic patients had a lower mean survival time than type I (34
versus 66 months P <0.0006). The mode of renal
replacement therapy (PD or HD) had no adverse effect on survival time.
Survivors less frequently had a history of CAD, POD and stroke than
non-survivors. In multivariate analysis ApoA-I, fibrinogen ,age and stroke
were independent predictors of cardiac and non-cardiac death in diabetic
patients with end-stage renal failure. Lipid values and nutritional state
did not independently predict the overall and cardiovascular mortality.
Conclusion: This study in dialysed diabetic patients
identified several predictors of death, some of which are susceptible to
intervention. 相似文献
22.
E. Wallenböck G. Koch 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1997,382(5):257-265
The intramedullary tibial nail with a proximal angle according to Herzog was developed in order to facilitate implantation. However, the modified technique of unreamed nailing also required a shift of the point of insertion; as a consequence the proximal angle required a considerable increase in the force necessary to introduce the nail. In a study using four cadaver bones and five commercially available unreamed femoral and tibial nails, the authors demonstrate this considerable increase in insertion force and the development of pressure in the medullary cavity. The measurements made with our experimental setup clearly show that the proximal angle of the unreamed tibial nails available for our series does not have a favourable influence on insertion behaviour. As it appears, it results in an increase in the force required for insertion of the nail, thus also causing a greater strain on the bone and an increase in pressure in the medullary cavity. In contrast, the continuous bend of the nail results in a much smoother course of pressure development in the medullary cavity, which does not reach the same high values as with the unreamed tibial nails, despite the fact that less time is required for insertion of the nail. In our opinion, modification of the axial shape of the nail would result both in better implantability and easier removal. We therefore advocate such a modification of the axial shape of intramedullary tibia nails. 相似文献
23.
Claude W. Drake DDS MPH MS Ronald J. Hunt DDS MS James D. Beck PhD Gary G. Koch PhD 《Journal of public health dentistry》1994,54(1):24-30
In this longitudinal study of a random sample of North Carolinians over the age of 65 and living in their homes, 325 blacks and 280 whites were examined and interviewed 18 months after baseline examinations. Coronal caries incidence was greater among whites than blacks. The increment due to teeth becoming root fragments were similar for both races; however, there were more newly crowned teeth among whites. Newly crowned surfaces were not used as part of the caries increment in logistic regression models to investigate potential risk predictors. For blacks, caries development over the 18-month period was associated with a higher lactobacillus score and more coronal caries at baseline, more previously filled coronal surfaces, and lack of active membership in clubs or other groups. For whites, having no self-reported tooth sensitivity, having a lower socioeconomic index score, taking antihistamine medications at baseline, and having the perception of more problems after the age of 40 than before were all associated with the development of coronal caries. 相似文献
24.
Accurate determination of renal function in patients with intestinal urinary diversions 总被引:2,自引:0,他引:2
The regular determination of renal function is a critical part of the management of patients who have had the urinary tract reconstructed with intestinal segments. These intestinal segments reabsorb urinary solutes and, thereby, complicate the determination of renal function by conventional methods. Urinary clearances of urea, creatinine and inulin were performed in patients with intestinal segments in the urinary tract and controls under varying diuretic conditions. Patients with intestinal diversions also underwent radioisotopic determination of renal function. The urinary clearances of urea, creatinine and inulin are highly dependent on the rate of urine flow in patients with intestinal segments in the urinary tract. Diuresis maximizes the urinary clearances of these solutes by minimizing intestinal reabsorption. Creatinine clearance prediction from the serum creatinine underestimates true glomerular filtration rate. Radioisotopic determination of renal function correlates poorly with true glomerular filtration rate. Only creatinine clearance measured under diuretic conditions correlates well with true renal function. Urine concentrating ability cannot be assessed accurately in patients with intestinal segments in the urinary tract, since osmolality rapidly equilibrates across the segments. 相似文献
25.
W G Weissert J M Elston E J Bolda C M Cready W N Zelman P D Sloane W D Kalsbeek E Mutran T H Rice G G Koch 《The Gerontologist》1989,29(5):640-649
We examined a nationally representative sample of 60 adult day care centers to describe the state of this evolving care modality after a decade's growth. Results indicate that day care centers can be categorized into three models of care, each of which serves a distinctive subpopulation. Model appropriateness was tested with analysis of variance of differences in participant characteristics. Services, staffing, costs, and other program features are contrasted among the three models. 相似文献
26.
27.
K Fishler C G Azen R Henderson E G Friedman R Koch 《American journal of mental deficiency》1987,92(1):65-73
Early treated phenylketonuric children who maintained a phe-restricted diet through age 10 were compared with those who discontinued the diet after age 6 on standardized tests of intelligence, school achievement, language, and perceptual skills. Mean IQ, reading, and spelling test scores improved between ages 6 and 10 for the on-diet children in comparison to those who were off diet. Mean scores on arithmetic, language, and perceptual skills, however, declined at a uniform rate for both groups. Children with PKU scored significantly lower than did their non-PKU siblings on tests of visual perception and visual-motor skills. We conclude that children with PKU should be maintained on a phe-restricted diet. 相似文献
28.
New aspects of the etiology of tendon rupture 总被引:2,自引:0,他引:2
E. Knörzer W. Folkhard W. Geercken C. Boschert M. H. J. Koch B. Hilbert H. Krahl E. Mosler H. Nemetschek-Gansler T. Nemetschek 《Archives of orthopaedic and trauma surgery》1986,105(2):113-120
Summary Native collagen fibers were exposed to different dynamic loads to simulate damage to tendons and ligaments relevant clinically and for sports medicine. The results suggest that the rupture of a tendon is caused at the submicroscopic fibrillar level. Not only slow or very fast elongation, but also very fast unloading of stretched fibers seems to be responsible for disseminated damage, which reduces the stability of a fiber. This damage is induced by intrafibrillar sliding processes, which occur only a few seconds before macroscopic slippage takes place. The significance of these events for the beginning and progress of repair in vivo is discussed. The conclusions are supported by simultaneous mechanical and radiological measurements, as well as by light- and electron-microscopic results.
Zusammenfassung Zur Simulierung klinisch bzw. sportmedizinisch relevanter Schäden an Sehnen und Bändern wurden native Kollagenfasern unterschiedlichen dynamischen Belastungen ausgesetzt. Die erzielten Ergebnisse sprechen dafür, die Ursachen einer Sehnenruptur im submikroskopischen fibrillären Bereich zu suchen. Sowohl eine langsame oder ruckartige Dehnung als auch eine ruckartige Entlastung zugbelasteter Fasern scheinen für das Auftreten disseminierter, die Faserstabilität reduzierender Gefügestörungen verantwortlich zu sein. Diese Gefügestörungen werden durch intrafibrilläre Gleitvorgänge eingeleitet, die an den noch voll belastbaren Fasern nur wenige Sekunden vor dem Einsetzen eines makroskopischen Faserfließens auftreten. Die Bedeutung dieser Ereignisse für den Beginn und Verlauf einer in vivo stattfindenden Reparationsphase wird erörtert. Die Aussagen werden gestützt durch simultane mechanische und röntgenographische Messungen sowie durch makroskopische, licht- und elektronenmikroskopische Befunde.相似文献
29.
S. Kølvraa J. Koch N. Gregersen P. K. A. Jensen A. L. Jørgensen K. B. Petersen K. Rasmussen L. Bolund 《Clinical genetics》1991,39(4):278-286
Two cloned DNA fragments, one derived from an alpha satellite subfamily common to chromosomes 13 and 21, and the other derived from a similar subfamily common to chromosomes 14 and 22, have been used as biotinylated probes in in situ hybridization studies. Under high stringency conditions, chromosome specific centromeric labelling can be obtained. The applications of this technique in clinical situations are illustrated on metaphases from a fetus with trisomy 21, a fetus with trisomy 13, and a child with clinical features of cat-eye syndrome. 相似文献
30.