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11.
OBJECTIVE: Induced hypothermia has been shown to be protective during cardiac surgery, but also in traumatic, ischemic, burn, and neurological injury. In previous in vivo animal experiments, we documented increased leukocyte/endothelial (L/E) cell interaction following normothermic extracorporeal blood circulation (ECC). This study was carried out to investigate whether reduced core temperature during ECC affects the damage to the microcirculation as evidenced by leukocyte adherence and edema formation. METHODS: Intravital fluorescence microscopy was used on the dorsal skinfold chamber preparation in Syrian golden hamsters. ECC was introduced via a micro-rollerpump (1 ml/min) and a 60 cm silicon tube (1mm inner diameter) shunted between the carotid artery and the jugular vein after application of 300IE Heparin/kg per body weight. Experiments were performed in chronically instrumented, awake animals (age 10-14 weeks, weight 65-75 g). Animals of the experimental group were cooled to 18 degrees C body temperature while ECC, followed by a rewarming period (n=7), controls experienced ECC under normothermia (37 degrees C, n=7). RESULTS: 30 min ECC at 18 degrees C resulted in a decrease of rolling and adherent leucocytes (stickers) in postcapillary venules after 1, 4 and 8h compared with the control group (119+/-46 vs. 274+/-113 n/mm2, P<0.05, mean+/-SD; n=7 in each group). Functional capillary density was significantly reduced during hypothermia (80+/-16 vs. 148+/-16 cm/cm2, P<0.05), but restored after rewarming. In contrast, edema formation was markedly increased during hypothermia. CONCLUSIONS: Hypothermia during ECC significantly reduced L/E cell interaction in the early post-ECC period. Hypothermia markedly reduced microvascular perfusion, but was completely restored upon rewarming. Despite a reduced number of adherent leukocytes, no protection of endothelial barrier function was seen as a consequence of induced hypothermia.  相似文献   
12.
Depressive symptoms are common in patients with neurodegenerative disorders. Imaging studies suggest that a disruption of frontal-subcortical pathways may underlie depression associated with basal ganglia disease. This pilot study tested the hypothesis that frontal dysfunction contributes to depression associated with multiple system atrophy (MSA) and progressive supranuclear palsy (PSP). Depressed patients with MSA (n = 11), PSP (n = 9), and age-matched controls (n = 25) underwent measures of cerebral glucose metabolism applying positron emission tomography with (18)F-fluorodeoxyglucose. Regional metabolism in the patient groups was compared to the normal subjects using the voxel-based statistical parametric mapping. Depressive symptom severity (Hamilton Depression Rating) and degree of locomotor disability (Hoehn & Yahr) were assessed in the patient groups. The association between prefrontal metabolism and the occurrence of depressive symptoms and the degree of locomotor disability was investigated. When compared to controls, MSA patients revealed significant metabolic decreases in bilateral frontal, parietal, and cerebellar cortex and in the left putamen. In PSP patients, significant hypometabolism was demonstrated in bilateral frontal cortex, right thalamus, and midbrain. Depression severity but not the patients' functional condition was significantly associated with dorsolateral prefrontal glucose metabolism in both patient groups. The findings of this pilot study support the hypothesis that depressive symptoms in MSA and PSP are associated with prefrontal dysfunction.  相似文献   
13.
In patients with renal failure, the high prevalence of vascular,valvular and soft-tissue calcifications and their consequencesfor cardiovascular outcomes have recently received much attention.Several studies documented that the calcification burden isassociated with increased morbidity and mortality in uraemia.In vitro and in vivo research has demonstrated that tissue calcificationis not just based on passive calcium and phosphate precipitation,but that active cellular processes such as osteogenic differentiationof vascular smooth muscle cells (VSMC) are involved and thata number of local and systemic calcium-regulatory factors controland prevent unwanted extra-osseous calcification. An importantfinding was the new understanding that calcium and phosphateare immediate inducers of osteogenic  相似文献   
14.
PURPOSE: A simple technical solution is presented to provide video transmission from the tip of a Bullard laryngoscope to a bedside video display, while the operator is still able to look through the viewing ocular of the Bullard laryngoscope during tracheal intubation. EQUIPMENT: This is achieved by insertion of an ultrathin fibreoptic video-endoscopic system into the working channel of the Bullard laryngoscope. Thereby the view from the distal blade tip is transmitted to a bedside monitor, without interfering with the use of the Bullards laryngoscope's original eyepiece. The presented technical solution allows video transmission without considerable additional weight normally associated with attaching video endoscopy cameras, light and camera cables to endoscopic devices. Thus, the Bullard laryngoscope remains lightweight and easy to maneuver. A screw-threaded adapter with a side-port is proposed to prevent displacement of the fibreoptic cable while still allowing application of oxygen. CONCLUSION: Experience and skills with tracheal intubation using the presented video-enhanced Bullard laryngoscope can be achieved in the originally intended way, while the supervisor or attending viewers can follow the tracheal intubation procedure on the video display.  相似文献   
15.
Islet cell carcinoma is rare. Even in advanced metastasizing tumors, relatively long survival times were reported. Aim of surgical treatment is complete removal of the tumor mass, if possible. When not, palliative procedures were described to be efficient in some of the cases. In the literature, among the first patients with regional metastasizing intraabdominal malignancies and upper abdominal exenteration, some cases with neuroendocrine tumors were reported. Aim of the following study is to describe the results in 4 patients with metastasizing islet cell carcinomas, which were treated by multi-visceral upper abdominal exenteration and combined orthotopic liver transplantation.  相似文献   
16.
Detailed characteristics of adolescent suicides (aged 13–19 years) with adjustment disorders (AD) (N=11) or no psychiatric diagnosis (N=3) in a nationwide adolescent suicide population (N=53) from Finland are presented. The data were collected in a psychological autopsy study of all suicides in Finland (N=1397) during a 12-month period in 1987–1988. Data collection included thorough interviews with the victims' family members and professionals, and information from official records. All the suicides with AD or no diagnosis were males. Most of these victims used highly lethal suicide methods. Previous psychiatric treatment and previous suicide attempts were rare. They were seldom under the influence of alcohol when committing suicide. The process leading to suicide seemed to be of relatively short duration. According to informant reports, withdrawn or narcissistic individual characteristics predominated in many cases. Psychosocial stressors preceding suicide often involved interpersonal losses or conflicts. Talking of suicidal intentions prior to the act was common, indicating the need to take seriously all adolescents' expressions of intended suicide, even in the absence of explicit psychopathology.
Zusammenfassung Es werden detaiilierte Beschreibungen von Selbst-morden im Jugendalter, verbunden mit Anpassungsstörungen (N=11) oder keiner psychiatrischen Diagnose (N=3) vorgestellt. Diese stammten aus der Gesamtheit aller jugendlichen Selbstmörder (N=53) aus Finnland. Die Daten wurden in einer psychologischen Obduktionsstudie aller Selbstmörder Finnlands (N=1397) während eines einjährigen Zeitraumes zwischen 1987 und 1988 gesammelt. Die Datenerhebung umfaßte ausgiebige Interviews mit den Familienmitgliedern, beteiligten Fachkräften und Informationen von offizieller Seite. Die Selbstmörder mit Anpassungstörungen oder keiner Diagnose waren alle männlich. Die meisten dieser Opfer benützten sehr letale Suizidmethoden. Vorangegangene psychiatrische Behandlungen und Selbstmordversuche waren selten. Sie standen nur selten unter dem Enfluß von Alkohol, als der Selbstmord vollzogen wurde. Der Prozeß, der zu dem Suizid führte, schien von relativ kurzer Dauer zu sein. Entsprechend den Angaben der Informanden prädominierten in vielen Fällen zurückgezogene oder narzißtische Persönlichkeitsmerkmale. Psychosoziale Stressoren, die dem Suizid vorangingen, umfaßten interpersonelle Verluste oder Konflikte. Häufig wurde über die Suizidabsichten vor der Tat gesprochen. Dies verdeutlicht die Notwendigkeit, alle Suizidäußerungen von Jugendlichen ernstzunehmen, selbst dann, wenn eine explizite Psychopathologie fehlt.

Résumé Les caractéristiques détaillées de suicides d'adolescents (âgés de 13 à 19 ans) avec troubles avec l'adaptation (AD) (N=11) ou l'absence de diagnostic psychiatrique (N=3) sur une population de suicides d'adolescents s'étendant sur l'ensemble du pays (N=53), la Finlande sont présentées. Les faits ont été collectés dans le cadre d'une étude d'autopsie psychologique de tous les suicides en Finlande (N=1397) pendant une période de 12 mois 1987–1988. Le recueil des faits incluait des interviews avec les membres de la famille des victimes et les professionels ainsi que les informations provenant de documents officiels. Tous les suicides avec un trouble de l'adaptation ou sans diagnostic étaient masculins. La plupart de ces victimes utilisait des méthodes hautement mortelles. Les traitements psychiatriques précédents et les tentatives précédentes de suicides étaient rares. Ils étaient rarement sous l'influence de l'alcool quand ils ont commis les suicides. Le processus conduisant au suicide semblait être de durée relativement brève. Selon les rapports d'information, une attitude de retrait ou des caractéristiques individuelles de retrait prédominaient dans la majorité des cas. Les facteurs de stress psycho-sociaux précédent le suicide impliquaient souvent des pertes inter-personnelles ou des conflits. Parler du désir du suicide devant le passage à l'acte était habituel indiquant la nécessité de prendre au sérieux tous les adolescents exprimant le désir de suicide, même en l'absence d'une psychopathologie explicite.
  相似文献   
17.
On the basis of observations of the course taken by 5 patients with so-called Locked-in Syndrome (LIS), the level of functional performance that can be achieved by long-term rehabilitation notwithstanding very severe initial symptoms is set out. The priority measures in the early phases of the condition and the particular problems of long-term rehabilitation are summarized in a checklist. Technical aids to ameliorate communication are dealt with in some detail. Special importance is attributed to patient-centered psychotherapeutic support and to family involvement.  相似文献   
18.
A knowledge of the alteration in the fibre type profile of paraspinal muscle associated with low back pain is essential for the design of successful rehabilitation programmes. In attempting to compare the muscles of patients with low back pain with those of controls, few previous studies have considered factors such as gender, age, and size of the subjects, each of which can potentially confound interpretation of the results. We obtained samples of lumbar paraspinal muscle during spinal surgery from 21 patients with low back pain and, using the percutaneous biopsy technique, from 21 control volunteers matched for gender, age, and body mass. The samples were subject to routine histochemicsl typcal analysis to determine characteristics of muscle fibre type. Compared with controls, the muscle of the patients had a significantly higher proportion of type-IIB (fast-twitch glycolytic) fibres than type- I (slow oxidatve) fibres. The mean size of a given fibre type did not differ between the patients and the controls. Consequently, the relative area of the muscle iccupied by type-IIB fibres was higher and that by type-I fibres Was lower in the patients. The patients had a greater number of muscle samples with more than 1% type-IIC fibres, and abnormalities that could be described as pathological were more marked in the patients than in the controls. In conclusion, the paraspinal muscles of patients who have low back pain display a more glycolytic (faster) profile; this can be expected to render them less resistant to fatigue.  相似文献   
19.
Urination frequency and cystic pressure resistance have been used as end-points to assess x-ray-induced changes of bladder function. Whole or half bladders of adult male rabbits were irradiated, caudally or cranially. The absorbed dose was 33 Gy, 36 Gy or 39 Gy, given in 5 daily fractions. Animals which received a whole bladder dose of 39 Gy or 36 Gy showed increased urination frequency and enhanced bladder pressure resistance during the whole follow-up time of 100 weeks, compared with the sham-irradiated controls. At half bladder irradiation, only the highest doses (39 Gy to the cranial part of the bladder and 39 Gy or 36 Gy to the caudal part) gave rise to a slight increase in frequency at about 20 weeks after exposure.  相似文献   
20.
Ziel der vorliegenden Untersuchung war es, das Ausma? der Hornhautsch?digung durch eine Kataraktextraktion im Hinblick auf das Hornhautendothel und die Hornhautdicke zu untersuchen. Patienten und Methode: In einer prospektiven Untersuchung wurde die Entwicklung der Hornhautdicke und der Endothelzelldichte an 48 Patienten untersucht. Die Patienten wurden mittels Phakoemulsifikation operiert. Die Hornhautdicke wurde dabei mit einem Ultraschallpachymeter bei 12 Uhr und im Hornhautzentrum und die Endothelzelldichte mit einer Endothelzellkamera an den gleichen Me?punkten pr?operativ sowie 4 Wochen, 4 Monate und 1 Jahr postoperativ bestimmt. Ergebnisse: Ein Jahr postoperativ nahm die Hornhautdicke nach Phakoemulsifikation an der 12-Uhr-Position um ca. 9% und im Hornhautzentrum um ca. 12% im Vergleich zum pr?operativen Wert zu. Die Endothelzelldichte war 1 Jahr postoperativ an der 12-Uhr-Position um ca. 27% und im Zentrum um ca. 18% reduziert. Das Patientenalter korrelierte signifikant mit dem Zellverlust an beiden Me?punkten. Bezüglich der Dickenzunahme ist keine signifikante Korrelation festzustellen. Schlu?folgerung: Nach einer Kataraktextraktion ist der Hornhautstoffwechsel reduziert. Als Indikator k?nnen der Verlauf der Endothelzelldichte und der Dicke herangezogen werden.   相似文献   
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