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141.
The effect of adrenalectomy on basal and hormone-stimulated amino-acid transport in liver was investigated by measuring the uptake of α-aminoisobutyric acid in freshly isolated rat hepatocytes. Adrenalectomy resulted in a 50% decrease m the transport capacity of hepatocytes; this change was accounted for by a diminution in the Vmax of a low affinity component of transport and specifically affected the A-transport system. Cortisone therapy fully restored the capacity of hepatocytes to transport amino acids. Sensitivity and responsiveness of hepatocytes from adrenalectomized animals to insulin, glucagon and dexamethasone, tested for the capacity of these hormones to stimulate AIB transport in vitro, were essentially identical with that of hepatocytes from control rats. The results support the concept of a positive (stimulatory) role of glucocorticoids in vivo, in the regulation of ammo acid transport in the liver.  相似文献   
142.
The effects of a single intraperitoneal injection of nicotine hydrogen tartrate (200 μg/kg) on the plasma levels of thyroxine, triiodothyronine and corticosterone were monitored over a 24 hour period. Nicotine did not alter the plasma levels of either of the thyroid hormones but did produce a significant increase in plasma corticosterone, an effect which peaked at 20 min post-injection and lasted for 45 min.  相似文献   
143.
A series of 76 pyonephrotic kidneys in 73 patients were drained by percutaneous nephrostomy (PN) tube and examined to evaluate the contribution of this technique to the treatment of pyonephrosis. In 71 patients, clinical symptoms disappeared 24–48 h after the procedure. Two patients died from sepsis subsequent to anuria and underlying malignancy. Once the acute phase had remitted, interventional procedures were carried out in 39 cases, and constituted the definitive therapy in 36. In 32 cases, elective surgery was the definitive therapy, including the 3 cases not resolved after interventional procedures. Three patients in whom the obstruction cleared spontaneously following PN needed no additional treatment. Major complications included 6 cases of sepsis, all of which resolved satisfactorily with proper medical therapy.  相似文献   
144.
The aim of the present study was to determine whether or not somatostatin can directly affect amino acid transport and cyclic AMP (cAMP) release in isolated rat hepatocytes. Somatostatin at 1.5 microgram/ml (1mumol/l) had no effect on basal uptake of alpha-aminoisobutyric acid (AIB). Similarly, the peptide was without effect on basal cAMP release. Somatostatin exerted a slight but statistically not significant inhibitory effect on glucagon-stimulated AIB uptake and cAMP release. These observations do not support the possibility that somatostatin might directly interfere with hepatic glucose metabolism by altering the entry of amino acids into the liver and--or--by affecting the level of endogenous cAMP.  相似文献   
145.
Physical interaction of apoptosis-inducing factor with DNA and RNA   总被引:2,自引:0,他引:2  
Apoptosis-inducing factor (AIF) is a mitochondrial flavoprotein, which upon apoptosis induction translocates to the nucleus where it interacts with DNA by virtue of positive charges clustered on the AIF surface. Here we show that the AIF interactome, as determined by mass spectroscopy, contains a large panel of ribonucleoproteins, which apparently bind to AIF through the RNA moiety. However, AIF is devoid of any detectable RNAse activity both in vitro and in vivo. Recombinant AIF can directly bind to DNA as well as to RNA. This binding can be visualized by electron microscopy, revealing that AIF can condense DNA, showing a preferential binding to single-stranded over double-stranded DNA. AIF also binds and aggregates single-stranded and structured RNA in vitro. Single-stranded poly A, poly G and poly C, as well double-stranded A/T and G/C RNA competed with DNA for AIF binding with a similar efficiency, thus corroborating a computer-calculated molecular model in which the binding site within AIF is the same for distinct nucleic acid species, without a clear sequence specificity. Among the preferred electron donors and acceptors of AIF, nicotine adenine dinucleotide phosphate (NADP) was particularly efficient in enhancing the generation of higher-order AIF/DNA and AIF/RNA complexes. Altogether, these data support a model in which a direct interaction of AIF contributes to the compaction of nucleic acids within apoptotic cells.  相似文献   
146.
The p53 family comprises the tumor suppressor p53 and the structural homologs p63 and p73. How the three family members cooperate in tumor suppression remains unclear. Here, we report different but complementary functions of the individual members for regulating retinoblastoma protein (RB) function during myogenic differentiation. Whereas p53 transactivates the retinoblastoma gene, p63 and p73 induce the cyclin-dependent kinase inhibitor p57 to maintain RB in an active, hypophosphorylated state. DeltaNp73 inhibits these functions of the p53 family in differentiation control, prevents myogenic differentiation, and enables cooperating oncogenes to transform myoblasts to tumorigenicity. DeltaNp73 is frequently overexpressed in rhabdomyosarcoma and essential for tumor progression in vivo. These findings establish differentiation control as a key tumor suppressor activity of the p53 family.  相似文献   
147.
AIM: The aim of this study was to describe the frequency of violence against personnel from residents and to identify the prevalence of burn-out among staff working in nursing homes. METHODS: The study was performed in two cities in the west of Turkey. A semi-structured questionnaire on violence and Pines' Burnout scale were distributed among all the staff working in six nursing homes, and 214 of them responded. RESULTS: Of the total number of respondents, 56% stated that they had been exposed to violence during the preceding year. More than 20% stated that they had reported violence to their supervisor. Less than 10% had received medical or psychological support following the event. Violent incidents were reported significantly more frequently among staff who reported problems working with elderly residents. There was no relationship between violence towards staff and burn-out. CONCLUSIONS: Violence is commonly experienced by care workers in nursing homes for the elderly. Strategies to improve occupational conditions in nursing homes are required.  相似文献   
148.
S Cam?es 《Hospital》1967,71(1):213-216
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149.
This community-based cross-sectional study in 533 participants from 135 households with multiple generations living in the same household aimed at investigating the relationship between Helicobacter pylori infection in children and the other household members. H. pylori infection in children was found significantly associated with the infection in mothers [OR (95% CI): 2.50 (1.19–5.26)], even after being adjusted for sex, age group and sibling number [adjusted OR (95% CI): 2.47 (1.12–5.47)]. It was also significantly associated with the infection in␣both parents [adjusted OR (95% CI): 4.14 (1.29–13.23)]. No significant association between H. pylori infection in the father, grandparent(s), uncle or aunt with that in their children was found. Results from the present study showed intra-familial transmission in a multi-generation population and supported the␣hypothesis of person-to-person transmission of H.␣pylori infection.  相似文献   
150.
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