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971.
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973.
Although heart transplantation is by now considered an established procedure in patients with terminal heart failure, there has been a stagnation or even a decline in the number of transplantations performed due to the decreased willingness of the public to provide organs. As a consequence of this development patients have to wait for a donor organ for a much larger time. The aim of this study was to examine patients especially during this very stressful period. From July 1995 to February 1997, 62 patients who had been continuously added to the waiting list were examined regarding their quality of life and emotional state. Completely assessed were 53 patients (participation rate: 85%). As compared to a healthy control group, patients with terminal heart failure on the waiting list reported their quality of life in the physical as well as the psychological area as significantly lower (p < 0.001). The areas of depression (p < 0.001) and anxiety (p < 0.001) also showed a significant difference. There was an obvious correlation (p < 0.01) between the key symptom of terminal heart failure-- dyspnoea--and the measured level of depression. This served to support the notion that there is a connection between the psychological and the somatic state in these severely ill patients. These results point to the necessity of supportive psychotherapeutic treatment during this very stressful time.  相似文献   
974.
Injecting scolicidal solutions into the hydatid cyst and packing the operative field with sponges soaked in scolicidal agents have been used to avoid dissemination of the parasite during surgery. In the first part of this invitro study, we tried to determine the scolicidal property of various agents in different concentrations and exposure times. In the second part, we tested whether sponges soaked in different type and concentrations of scolicidal agents have any role beyond being a mechanical barrier. 20% saline, 3% hydrogen peroxide, 1.5% cetrimide-0.15% chlorhexidine (10% Savlon), 95% ethyl alcohol, 10% polyvinylpirrolidone-iodine (Betadine) and their further dilutions were used in this study. Protoscoleces were obtained from the cyst containing livers of the sheep and viability was determined with dye-uptake (0.1% Eosin) and flame cell activity. Savlon was found to be the least concentration dependent scolicidal agent among those studied. Scoleces sprayed on sponges soaked in 20% saline, 95% ethyl alcohol, Betadine and 3% hydrogen peroxide were killed after 15 minutes. 3% and 10% saline and normal saline were ineffective. Sponges work not only as a mechanical barrier but also as a chemical one if the agent is chosen correctly. In purely cystic hydatid liver disease, the risk of dissemination of the cyst contents can be avoided by injection of a potent scolicidal agent such as Savlon.  相似文献   
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Thoracoscopy can be done safely and effectively through working ports placed in the axilla in patients whose pathology is in the upper half of the thorax. We have used this technique successfully in 37 patients with no complications. Advantages include superior cosmesis, optimal access to the apex of the chest, and, if necessary, easy conversion to axillary thoracotomy.  相似文献   
978.
The PTEN/MMAC1 phosphatase is a tumor suppressor gene implicated in a wide range of human cancers. Here we provide biochemical and functional evidence that PTEN/MMAC1 acts a negative regulator of the phosphoinositide 3-kinase (PI3-kinase)/Akt pathway. PTEN/MMAC1 impairs activation of endogenous Akt in cells and inhibits phosphorylation of 4E-BP1, a downstream target of the PI3-kinase/Akt pathway involved in protein translation, whereas a catalytically inactive, dominant negative PTEN/MMAC1 mutant enhances 4E-BP1 phosphorylation. In addition, PTEN/MMAC1 represses gene expression in a manner that is rescued by Akt but not PI3-kinase. Finally, higher levels of Akt activation are observed in human prostate cancer cell lines and xenografts lacking PTEN/MMAC1 expression when compared with PTEN/MMAC1-positive prostate tumors or normal prostate tissue. Because constitutive activation of either PI3-kinase or Akt is known to induce cellular transformation, an increase in the activation of this pathway caused by mutations in PTEN/MMAC1 provides a potential mechanism for its tumor suppressor function.  相似文献   
979.
In Experiment 1, rats were given a 1% lead acetate diet from Day 100 of life to the termination of the experiment. After 82 days of lead feeding behavioral tests were started. Lead exposure increased wheel-turning hyperactivity produced by food deprivation and phenylethylamine injection. Lead produced no activity change in the unchallenged condition. In the open field, lead-exposure rats were less responsive to the stimulating action of PEA and amphetamine and to the sedating action of pentobarbital. In Experiment 2, the interaction of lead with food deprivation of PEA on wheel-turning was replicated in naive animals given only a 32-day exposure. Chemical analysis was made of tissues. Ingested lead entered the brain. Regional steady-state levels of brain norepinephrine, dopamine and serotonin were not altered by lead treatment when measured following four days of starvation at a time when lead-induced behavioral change was distinct. It was concluded that pharmacological challenges on activity may be sensitive indicators of lead exposure, but the type of activity measure is critical.  相似文献   
980.
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