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61.
Current interest in brain temperature and selective brain cooling makes a method allowing for continuous monitoring of intracerebral temperature in humans desirable. The authors describe a safe, simple, and reliable technique using a thermocouple of copper and constantan in combination with intraventricular monitoring of intracranial pressure for measurement of brain temperature in neurosurgical patients. 相似文献
62.
Effects of enteral feedback inhibition on motility,luminal flow,and absorption of nutrients in proximal gut of minipigs 总被引:2,自引:0,他引:2
Andreas Huge Eckhard Weber Prof. Dr. Hans-Jörg Ehrlein 《Digestive diseases and sciences》1995,40(5):1024-1034
We wanted to clarify whether the postprandial intestinal feedback control activated by nutrients in the distal gut exerts different effects on motility, transit of digesta, and absorption of nutrients in the proximal gut. Additionally, interrelationships among motility, transit, and absorption were to be elucidated because these relationships have only been investigated in the fasted state. In five minipigs, a 150-cm segment of the proximal jejunum was isolated by two cannulas. Motility of the jejunal segment was recorded by multiple strain gauges and analyzed by computerized methods. Markers (Cr- and Cu-EDTA) were used for the measurement of the flow rate, transit time, and absorption of nutrients. After a meal, the test segment was perfused with 2 kcal/min of an elemental diet over a period of 90 min. A feedback inhibition was activated by infusion of nutrients into the midgut at rates of 1–4 kcal/min. Saline was infused as control. With increasing energy loads infused into the midgut, the motility index and the length of contraction waves decreased, whereas the incidence of stationary contractions increased, ie, the motility changed from a propulsive to a segmenting pattern. These modulations of motility were associated with a linear decrease in the flow rate and a linear increase in transit time. Flow and transit were linearly correlated with each other. Additionally, the reduction in flow rate and the delay in luminal transit were associated with a linear increase in the absorption of nutrients. However, the increase in absorption induced by the feedback mechanism was small (7.3–13.4%) compared to the marked inhibition of the motility parameters (54–64%), the flow rate (59%), and the delay of transit (5.8-fold). Feedback control primarily modulated motor patterns and luminal flow, whereas the small increase in absorption was only a side effect due to the longer contact time of the nutrients with the mucosa.The study was supported by the Deutsche Forschungsgemeinschaft, grant Eh 64/6-3. 相似文献
63.
64.
L. Tsai Å. Pousette K. Carlström M. Askenberger C. Johansson 《Scandinavian journal of medicine & science in sports》1992,2(1):10-15
A 2-week training period 2000 meters above sea level performed by 6 male elite Swedish runners influenced neither basal anabolic (total and non-sex hormone-binding globulin (SHBG)-bound testosterone (NST) and insulin-like growth factor-1 (IGF-1) nor catabolic (cortisol) hormones when comparing serum levels prior to and after the training camp. The anabolic vs catabolic hormone balance, expressed as the NST: cortisol ratio, also remained unchanged as well as SHBG and body mass. Thus, training at 2000 meters above sea level, often practised by elite runners to improve performance in competition at sea level, does not result in a catabolic situation after return to sea level, as measured by peripheral hormones. However, the adaptation to high altitude was associated with a slight (NS) decrease in testosterone as well as in anabolic vs catabolic balance as measured the third day at high altitude. Simultaneously, a decrease in subjective performance was claimed by the runners, but could not be shown by objective measurements. From day 3 to day 9 at high altitude, all runners claimed a subjective recuperation of performance. Total and non-SHBG-bound testosterone increased significantly from day 3 at high altitude to the first post-camp sea-level test. The results reflect the necessity of adaptation when travelling to races at different altitudes. The Swedish runners had significantly higher cortisol, total testosterone and NST levels compared with basal values of a group of 17 elite Kenyan runners living and training at high altitude. Since the NST cortisol and IGF-1 values were not lower, a catabolic state or malnutrition was not likely to be present. The results might reflect an adaptation to altitude or ethnic variations. 相似文献
65.
66.
V Brattstr?m J McWilliam G Semb O Larson 《Nordisk plastikkirurgisk forening [and] Nordisk klubb for handkirurgi》1992,26(1):55-63
Lateral skull radiographs of 85 patients with unilateral clefts of the lip, alveolus and palate treated according to four different regimes were compared longitudinally, at three different ages, regarding mandibular and vertical facial development. It was found that there were no lasting differences in mandibular morphology resulting from regimes including primary or early secondary bone grafting. The non grafted group, however, showed increased mandibular length and anterior height. The jaw angle was increased and there was a more favourable sagittal jaw relationship. Regimes that included primary bone grafting were associated with reduced upper anterior facial height, which resulted in less harmonious facial proportions compared with treatment regimes including early secondary bone grafting done during the mixed dentition, or no bone grafting at all. Vertical development was greatest where bone grafting was excluded. 相似文献
67.
P. Rokkanen O. Böstman E. Hirvensalo E. A. Mäkelä E. Partio H. Pätiälä S. Vainionpää K. Vihtonen P. Törmälä 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》1992,2(2):107-110
Résumé L'utilisation de matériaux d'ostéosynthèse biodégradables a l'avantage d'éviter la réintervention pour extraire le matériel. Les biomatériaux de polymères polyglycolides ont été expérimentés sur plus de 3 600 animaux de laboratoire avant leur introduction en pratique clinique. Depuis 1984 nous les avons utilisés comme matériau d'ostéosynthèse dans près de 1 700 cas parmi lesquels 880 cas de fracture malléolaire, 226 cas d'ostéotomie en chevron pour hallux valgus, 65 cas de fracture de la tête radiale et 54 cas de fracture de l'olécrane. Parmi les 800 premiers cas traités par broches biodégradables nous avons obtenu des résultats favorables et sans incidents dans 91 pour cent des cas. Il y eut 7 cas de fixation défaillante nécessitant une réintervention. Il y a eu 7 cas d'infection superficielle et 3 cas d'infection profonde. Nous avons observé la formation d'une collection séreuse sous-cutanée sans influence sur le résultat radiologique ou clinique dans 52 cas (6,5 %). Au vue de ces résultats et compte tenu des avantages économiques et psychologiques des matériaux biodégradables (pas de réintervention), on peut penser que l'usage de biomatériaux rivalise favorablement avec l'usage de matériaux conventionnels dans certains types d'ostéosynthèse.
Utilization of biodegradable implants in the surgical treatment of fractures and osteotomies
Summary The utilization of biodegradable implants instead of metals in orthopaedic surgery abolishes the need to remove the fixation material. For this study biodegradable rods and screws of self-reinforced polyglycolide, polylactide and lactide-glycolide copolymer were developed and manufactured. The clinical introduction of these implants was preceded by thorough experimental studies with 3 600 animals. From November 1984 the developed biodegradable method of osteofixation was used in 1 700 operations. These included 880 displaced malleolar fractures, 226 chevron-osteotomy for hallux valgus, 65 displaced fracture of the radial head, 54 displaced frature of the olecranon and other fresh fractures or orthopaedic operations. In the first 800 cases operated on using self-reinforced polyglycolide rods the postoperative course was uneventful (91%). Because of failure in the fixation reoperation was needed in 7 cases. A superficial wound infection was observed in 7 cases, deep infection in 3 and transient fluid accumulation in 52 cases (6,5%). Fluid accumulation did not influence the radiological or clinical end-result. The advantages of biodegradable fixation are many-sided. There is a costbenefit and clinical capacity is free for other use, and psychological advantages must be emphasised because removal of implants is not needed. The over all results of this study were considered favourable.相似文献
68.
Complications following combined transrectal aspiration and core biopsy of the prostate 总被引:2,自引:0,他引:2
O Gustafsson U Norming C R Nyman M Ohstr?m 《Scandinavian journal of urology and nephrology》1990,24(4):249-251
Ultrasound guided biopsy of the prostate with fine needle (22G) as well as trucut needle (18G) was performed in 145 patients with a suspicion of prostate cancer. After three weeks all patients were interviewed about complications associated with the biopsy. Hematuria and/or hemospermia occurred in 2/3 of the patients. None of the hemorrhages was severe and all ceased spontaneously. E. coli infection of the urinary tract occurred in 9 cases (6.2%). Five of the infections caused high fever and necessitated hospital care with parenteral antibiotics for 1 to 8 days. The patients with infection had no signs of immunological defects by which they might have been identified before the biopsy. As a consequence of these observations we now use prophylactic antibiotics when core biopsy of the prostate is performed transrectally. 相似文献
69.
B Sandstr?m A Cederblad B Stenquist H Andersson 《European journal of clinical nutrition》1990,44(10):705-708
Colonic retention of zinc and calcium was studied after installation during colonoscopy in 11 patients of a solution of 30 mumol zinc, 6.4 mmol calcium and 500 mumol inositol hexaphosphate (phytic acid) labelled with 65Zn and 47Ca. Whole-body retention of the radionuclide at day 13 was 1.0 +/- 1.0 per cent (mean +/- s.d.) for zinc and 4.0 +/- 2.9 per cent for calcium. The retention of zinc but not of calcium was lower than observed earlier under similar conditions from a solution not containing phytic acid and indicates formation of an indigestible complex between phytic acid and zinc. Addition of amino acids to the solution in 3 subjects did not seem to affect the retention of zinc and calcium. 相似文献
70.
F. Röpke K. Klingebiel H. J. Hein R. Taute 《Archives of gynecology and obstetrics》1993,254(1-4):1159-1160
Schlu?folgerungen Aus der Me?wert-Verteilung der Grauwerte im Sonogramm lassen sich Kennwerte berechnen, die eine computergestützte sonographische
Reifebeurteilung der Plazenta erm?glichen. Allerdings sind die Verteilungsparameter (Median, Varianz, Schiefe, Exze?) abh?ngig
von den Ger?teparametern. Zuverl?ssiger ist die Berechnung von Kennwerten, die sich auf die strukturellen Eigenschaften des
Sonogramms beziehen. Bei den hier dargestellten Untersuchungen k?nnen Kennwerte für den Kontrast bzw. für die Ansammlung gleichartiger
Grauwerte um einen bestimmten Punkt die sonographische Beurteilung der Plazenta optimieren. Damit erweitern sich die M?glichkeiten
für die Zustandsdiagnostik der intrauterinen Lebensbedingungen. 相似文献