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991.
A 25-year-old heroin-addict had four episodes of acute hepatitis, each of them associated with thrombocytopenia. Serologically, hepatitis A and B as well as cytomegalo- or Epstein-Barr virus infections were excluded. High levels of circulating immune complexes and antibodies reacting with aminophospholipids, a component of both liver cell and platelet membranes, were detected during the last two attacks of hepatitis, but were absent during remission. Platelet-associated antibodies of the IgM class paralleled the 'anti-phospholipid' antibodies during the fourth attack. These findings demonstrate an immunological basis of the thrombocytopenia and point to the possibility of a direct association between liver cell injury and peripheral platelet destruction in certain patients.  相似文献   
992.
In response to graded doses of intravenous 13-norleucine-motilin (13-nle-motilin)--a synthetic analogue of motilin and biologically equivalent to the natural polypeptide-, gastric mucosal blood flow (GMBF) in canine vagally denervated fundic pouches was studied using the aminopyrine clearance technique. As 13-nle-motilin did not exert any detectable effect on gastric secretion of hydrogen ions, intraluminal instillation of 160 mM HCl was used to provide a pH gradient allowing aminopyrine to move into the pouch lumen. With increasing doses of 13-nle-motilin, GMBF increased to 148% of control values; pepsin secretion - due to augmented pepsin concentration - rose concomitantly. Enhanced pepsin secretion was not accompanied by an increase in cyclic 3',5'-adenosine monophosphate secretion.  相似文献   
993.
In 20 patients with chronic neutropenia, serum lactoferrin (S-LF) and serum myeloperoxidase (S-MPO) levels were assessed. By immunofluorescence, granulocyte-bound immunoglobulins were detected in 12 patients, whereas circulating immune complexes were found in the blood of 8 patients by the 125-I-C1q-binding test (C1q-BT). In both groups of patients, there was a relative increase of S-LF and a relative or sometimes absolute increase of S-MPO. In the latter group, results of the C1q-BT correlated positively with S-MPO but negatively with neutrophil counts. No correlations between S-LF or S-MPO and the results of the granulocyte immunofluorescence test were found. Our results suggest that S-LF and S-MPO levels may be helpful in the further study of patients with chronic neutropenia, to gain more insight into the pathogenetic mechanisms operative in this disease.  相似文献   
994.
PURPOSE: To evaluate and compare the efficacy of proximal versus distal embolus protection devices (EPD) during carotid artery angioplasty/stenting (CAS) based on diffusion-weighted magnetic resonance imaging (DW-MRI). METHODS: Forty-four patients (31 men; mean age 68 years, range 48-85) underwent protected CAS and had DW-MRI before and after the intervention. The cohort was analyzed according to the type of EPD used: a proximal EPD was deployed in 25 (56.8%) patients (17 men; mean age 66 years, range 48-85) and a distal filter in 19 (14 men; mean age 70 years, range 58-79). Fifteen (60.0%) patients with proximal protection were symptomatic of the target lesion; in the distal protection group, 10 (52.6%) were symptomatic. RESULTS: New lesions were seen on the postinterventional DW-MRI in 28.0% (7/25) of the proximal EPD group versus 32.6% (6/19) of those with a distal filter (p = NS). The majority were clinically silent. The new lesions in the vascular territory of the stented carotid artery in the group as a whole and per patient were fewer in the proximal EPD group (p = NS). No significant differences were noted in the T(2) appearance of the new lesions or the number of new lesions observed away from the vascular territory of the stented artery. CONCLUSION: Proximal embolus protection devices show a nonsignificant trend toward fewer embolic events, which warrants large-scale studies. Furthermore, proximal protection devices can be useful to control and treat acute in-stent thrombosis.  相似文献   
995.
Multiple duodenal polyps in uraemia: a little known clinical entity   总被引:2,自引:0,他引:2       下载免费PDF全文
Multiple duodenal polyps were found by endoscopy in five out of 33 patients with chronic renal failure and in one of 300 controls. In the uraemic cases the polyps were caused by circumscribed nodular hyperplasia of Brunner's glands. One of these five patients later underwent surgery for duodenal obstruction caused by the polyps; the other patients were asymptomatic. One of the controls had multiple duodenal polyps. The recorded incidence of multiple duodenal polyps was significantly higher among patients with chronic renal failure than in patients without renal disease. Patients with chronic renal failure and polyps did not differ significantly from the other renal patients in the comparison of variables such as gastric acid secretion, serum concentrations of gastrin and group I pepsinogens or mean length of dialysis treatment. The mean pH of gastric resting juice was significantly higher, however, in uraemic patients with polyps than in those without. Uraemic patients displayed a gastric acid secretion capacity within normal range, and significantly raised serum gastrin and group I pepsinogen concentrations.  相似文献   
996.
BackgroundFractional flow reserve (FFR) is a valid surrogate for hemodynamic significance in stenotic native coronary arteries. The aim of this study was to examine the value of FFR compared to stress perfusion myocardial scintigraphy (SPMS) in patients with coronary stent restenosis.MethodsWe studied 42 patients, aged 62 ± 10 years, with stent restenosis 5.3 ± 1.6 months after coronary stent implantation. All patients had a single coronary lesion of intermediate severity (diameter stenosis 40–70%). FFR measurement, SPMS, and quantitative angiography of the stent stenosis were performed in all patients.ResultsThe mean percentage in stent diameter stenosis was 53 ± 9%. FFR was 0.77 ± 0.15. In 20 patients FFR was below 0.75. Nineteen patients had reversible perfusion defects in SPMS. FFR showed good diagnostic accuracy for the detection of reversible perfusion defects in SPMS (AUROC 0.86, 95% CI 0.74–0.98). The percentage of agreement of SPMS and FFR was 88%, with the best cutoff value of 0.75 for FFR.ConclusionsA FFR value of 0.75 is not only valid for diagnosing significant native coronary stenosis, but also for stent restenosis. Thus, FFR measurement should be taken into account when making decisions regarding patients with stent restenosis.  相似文献   
997.
998.
Immortalization and malignant transformation are important steps in tumor development. The ability to induce these processes from normal human epithelial cells with genetic alterations frequently found in the corresponding human cancer would significantly enhance our understanding of tumor development. Alterations in several key intracellular regulatory pathways (the pRB, p53, and mitogenic signaling pathways and the telomere maintenance system) appear to be sufficient for the neoplastic transformation of normal human cells. Nevertheless, in vitro transformation models to date depend on viral oncogenes, most prominently the simian virus 40 early region, to induce immortalization and malignant transformation of normal human epithelial cells. Here, we demonstrate a transformation model creating oral-esophageal cancer cells by using a limited set of genetic alterations frequently observed in the corresponding human cancer. In a stepwise model, cyclin D1 overexpression and p53 inactivation led to immortalization of oral keratinocytes. Additional ectopic epithelial growth factor receptor overexpression followed by c-myc overexpression as well as consecutive reactivation of telomerase induced by epithelial growth factor receptor sufficed to transform oral epithelial cells, truly recapitulating the development of the corresponding human disease.  相似文献   
999.
Theophylline enhances GH-secretion in vitro, whereas in vivo a slight decrease of basal GH-levels has been observed. In the present study the effect of theophylline on the GH-responsiveness to acute and continuous administration of growth hormone releasing hormone (GHRH) was investigated. The following protocol was performed. GHRH study. Fifty micrograms GHRH was given as an iv bolus followed by constant GHRH-infusion (100 micrograms/h) over 2 h after which another GHRH bolus of 50 micrograms was given. GHRH plus theophylline study. GHRH was administered as in the first study and theophylline was infused at a constant rate of 3.56 mg/min over 3 h, starting one h before the GHRH bolus. Theophylline study. Only saline and theophylline were infused. GHRH alone led to a GH-rise within 30 min with a maximum of 22.8 +/- 7.2 ng/ml (mean +/- SE) after which GH-levels decreased despite continuous GHRH-infusion to a nadir of 12.1 +/- 4.4 ng/ml at 105 min. The second GHRH bolus led to a minimal GH-increase (13.3 +/- 6.4 ng/ml at 135 min). Theophylline administration resulted in blunting of the GH-response to GHRH in all volunteers, with GH levels fluctuating between 4-6 ng/ml throughout GHRH-administration. Theophylline alone did not affect GH-levels in three subjects studied, whereas in the other one a GH secretory episode 90 min after administration of the drug was observed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
1000.
The diagnostic work-up for the first syncopal episode of a 14-year-old female adolescent revealed the morphology of an isolated myocardial non-compaction on echography. Angiography and biopsy of the left ventricle confirmed the diagnosis. Despite a reduced shortening fraction (FS 21%) and frequent premature atrial beats, there were no further cardiac or extracardiac symptoms. After establishment of therapy with beta-blockade, digitalis, angiotensin converting enzyme inhibition and acetylsalic acid, the follow-up over 24 months was good; the implantation of an automatic implantable cardioverter-defibrillator is planned.  相似文献   
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