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71.
Heart failure is a complex clinical syndrome. There is evidence for a genetic contribution to the pathophysiology of heart failure. Considering the fundamental role of neurohormonal factors in the pathophysiology and progression of cardiac dysfunction and hypertrophy, variants of genes involved in this system are logical candidate genes in heart failure. In this report, genetic polymorphisms of the major neurohormonal systems in heart failure will be discussed. Studies on polymorphisms of the renin-angiotensin-aldosterone system (RAAS), adrenergic receptor polymorphisms, endothelin (receptor) polymorphisms, and a group of miscellaneous polymorphisms that may be involved in the development or phenotypic expression of heart failure will be reviewed. Research on left ventricular hypertrophy is also included. The majority of genetic association studies focused on the ACE I/D polymorphism. Initial genetic associations have often been difficult to replicate, mainly due to problems in study design and lack of power. Promising results have been obtained with genetic polymorphisms of the RAAS and sympathetic system. Considering the evidence so far, a modifying role for these polymorphisms seems more likely than a role of these variants as susceptibility genes. Besides the need for larger studies to examine the effects of single nucleotide polymorphisms and haplotypes, future studies also need to focus on the complexity of these systems and study gene-gene interactions and gene-environment interactions.  相似文献   
72.
73.
We examined the in vivo mechanisms of amylin-induced resistance in concious rats (n = 18). During 180-min euglycemic insulin-clamp (21.5 pmol.kg-1.min-1) studies, amylin (50, 200, or 500 pmol.kg-1.min-1; plasma concentration from 3 x 10(-10) to 9 x 10(-9) M) infusion determined a 19-27% reduction in glucose uptake (117.8 +/- 7.0 vs. 145.8 +/- 11.0, 107.1 +/- 9.2 vs. 145.1 +/- 6.7, and 105.0 +/- 7.2 vs. 144.4 +/- 7.0 mumol.kg-1.min-1 at 50, 200, or 500 pmol.kg-1.min-1, respectively, P less than 0.01) versus insulin alone, whereas 10-pmol.kg-1.min-1 amylin infusion (plasma concn 5 x 10(-11) M) failed to affect insulin-mediated glucose disposal. After amylin infusion, the contribution of whole-body glycolysis to overall glucose disposal increased from 43-48 to 62-79%, whereas muscle glycogen synthesis decreased significantly at all peptide concentrations greater than 3 x 10(-10) M, completely accounting for the decrease in glucose uptake. Skeletal muscle glucose-6-phosphate concentration rose from 0.219 +/- 0.038 mumol/g (insulin alone) to 0.350 +/- 0.018, 0.440 +/- 0.020, and 0.505 +/- 0.035 mumol/g (insulin plus amylin at 50, 200, or 500 pmol.kg-1.min-1, P less than 0.01). Suppression of hepatic glucose production by insulin was unaffected by a 50-pmol.kg-1.min-1 amylin infusion (18.5 +/- 4.3 vs. 21.7 +/- 2.9 mumol.kg-1.min-1), whereas it was slightly but significantly impaired by amylin infusion at 200 pmol.kg-1.min-1 (17.8 +/- 3.9 vs. 24.7 +/- 4.5 mumol.kg-1.min-1, P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
74.
Abstract: The development of a teaching package for nurse educators on drug and alcohol problems is described and the contents of its 16 modules outlined.  相似文献   
75.
We report on a 26-year-old female affected by Noonan syndrome (NS), a congenital disorder characterized by various phenotypic features and congenital anomalies) associated with a variety of autoimmune diseases, including systemic lupus erythematosus, celiac disease, and Hashimoto thyroiditis. Autoimmunity is seldom described in NS and the association between this congenital disease and three autoimmune disorders has not been previously reported. Should the occurrence of autoimmune disorders in NS be confirmed, a relevant clinical and laboratory evaluation of NS patients should be performed in order to clarify whether the immune system involvement represents only an occasional event or is a feature of the disease.  相似文献   
76.
This study compares the effects of the cancer experience on various aspects of marital and sexual functioning (e.g., communication, emotional support, body image, sexual satisfaction and frequency) for two groups of long-term cancer survivors (testicular cancer and Hodgkin's disease) and their spouses. Comparisons between the two patient groups showed significantly more survivors of Hodgkin's disease than testicular cancer reporting the emergence of special issues and changes in the marital relationship. No differences emerged between the spouse groups on sexual functioning variables; however, spouses of survivors of Hodgkin's disease were more likely than spouses of survivors of testicular cancer to report the development of special issues and communication difficulties. A substantial proportion of both survivor groups disclosed negative changes in body image and sexual frequency. Majorities of both survivors and spouses acknowledged that the illness had drawn them closer together. When representative marital/sexual functioning variables were used to predict Family Environment Scale (FES) scores for survivors and for spouses, changes in the spouse's importance, influence of the illness on the relationship, and changes in sexual frequency emerged as significant predictors. The clinical significance of long-term changes in marital and sexual functioning for the couple and the need for therapeutic interventions are discussed.  相似文献   
77.
The content of dolichol, an isoprenoid present in all biological membranes, was determined in isolated sinusoidal liver cells after treatment of rats for 2 and 4 months with a low dosage of the hepatotoxin thioacetamide. The significant decrease in dolichol observed in hepatocytes after 2 months might be explained by peroxidation of the isoprenoid. At the same time point, retinol was retained, and decreased only after 4 months of treatment. After 4 months of treatment therefore both lipids decreased. In a subfraction of hepatic stellate cells, Ito-1 cells, the main storage site of vitamin A, dolichol decreased significantly only after 4 months. A remarkable difference from hepatocytes is that in Ito-1 cells retinol content significantly decreased after 2 months of treatment. In another subfraction, Ito-2 cells, the content of the two isoprenoids decreased in parallel. This heterogeneous subfraction might represent those transitional hepatic stellate cells that, while losing retinol, are in the process of differentiating into myofibroblasts secreting extracellular matrix components. In Kupffer cells and sinusoidal endothelial cells, impairment of dolichol might be observed later, only after 4 months of treatment, while retinol decreases uniformly over time. Starting after two months of treatment, the decrease of dolichol and the increase of retinol in hepatocytes, at the same time as retinol decreases in hepatic stellate cells, might be taken as an early index of incipient liver injury due to thioacetamide. This hypothesis is discussed with regard to a role of dolichol in the modulation of membrane fluidity for intracellular and intercellular retinol transport.  相似文献   
78.
In erythropoietic protoporphyria (EPP), there is excessive production of protoporphyrin, primarily in the bone marrow, resulting in increased biliary excretion of this heme precursor. Some patients will develop progressive liver disease that may ultimately require liver transplantation. However, excessive production of protoporphyrin by the bone marrow continues after transplantation, which may cause recurrent disease in the allograft. This study was performed to define post-transplant survival, the risk of recurrent disease, and specific management issues in patients transplanted for EPP liver disease. The patients studied consisted of twelve males and eight females, with an average age of 31 (range, 13-56) years at the time of transplantation. The estimated maximum MELD score prior to transplant was 21 (range, 15-29). Unique complications in the perioperative period were light induced tissue damage in four patients and neuropathy in six, requiring prolonged mechanical ventilation in four. Patient and graft survival rates were 85% at 1 year, 69% at 5 years, and 47% at 10 years. Recurrent EPP liver disease occurred in 11 of 17 patients (65%) who survived more than 2 months. Three patients were retransplanted at 1.8, 12.6, and 14.5 years after the initial transplant for recurrent EPP liver disease. In conclusion, the 5-year patient survival rate in patients transplanted for EPP liver disease is good, but the recurrence of EPP liver disease appears to diminish long term graft and patient survival.  相似文献   
79.
Zusammenfassung Anamnese und Diagnostik: Ein 75-jähriger Patient wies neben unspezifischen anamnestischen Symptomen (Appetitverlust, Merkfähigkeitsstörung und Muskelschwäche) klinisch diskrete Beinödeme, abgeschwächte Muskeleigenreflexe und eine deutliche Gedächtnisstörung auf. Aufgrund einer euvolämischen, laborchemisch hypoosmolaren Hypoatriämie und eines Urinnatriums im Normbereich wurde als Arbeitsdiagnose von einem Syndrom der inadäquaten ADH-Sekretion (SIADH) ausgegangen. Während sich weder in der Anamnese noch in den folgenden Untersuchungen eine dem SIADH zugrunde liegende Pathologie eruieren ließ, ergab sich in den weiteren Laboruntersuchungen der Befund einer ausgeprägten Hypothyreose. Die Hyponatriämie bei Hypothyreose spiegelt eine Komponente der renalen Funktionsstörung bei Schilddrüsenhormonmangel wider. Therapie und Verlauf: Nach Flüssigkeitsrestriktion und Hormonsubstitution erreichte der Patient schnell normale Natriumwerte und zeigte eine deutliche Besserung seiner kognitiven Fähigkeiten. Schlussfolgerung: Als Schlussfolgerung aus dieser Kasuistik wird Zurückhaltung bei der Diagnose eines SIADH empfohlen, bevor nicht eine sorgfältige Untersuchung des Nebennieren- und Schilddrüsenhormonstatus erfolgt ist. Abstract Case History and Diagnosis: A 75-year-old male patient presented with a history of anorexia, muscle weakness, and increasing memory loss. He had mild pedal edema and decreased deep tendon reflexes. As the laboratory tests showed hypoosmolar hyponatremia and urinary sodium within the normal range, a syndrome of inappropriate ADH secretion (SIADH) was presumed. While neither the medical history nor any of the diagnostic procedures revealed any underlying pathology explaining the SIADH, laboratory tests showed significant hypothyroidism. Hypothyroid states are associated with significant changes in renal function, one of which is hypoosmolar hyponatremia. Treatment and Course: Treatment included fluid restriction and hormone substitution and resulted in a quick correction of the hyponatremia and a clear improvement of the patient's cognitive function. Conclusion: It is concluded that the diagnosis of SIADH should only be made after thorough investigation of the adrenal and thyroid hormone status.  相似文献   
80.
Forty-seven patients aged more than 75 years with acute pancreatitis were studied. The most common cause of acute pancreatitis was biliary tract stones. The clinical presentation and severity of the disease as judged by the number of poor prognostic factors were not different from the group of patients aged less than 75 years. The mortality rate in the older group was thrice that of the younger group (21.3% versus 7.24%). The higher mortality rate was explained by a higher incidence of deaths related to complications of biliary stones and coincidental diseases. Significantly more aged patients with mild disease died, indicating the limitation of predictive ability of the scoring system in acute pancreatitis of the aged.  相似文献   
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