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OBJECTIVE: The combination of mifepristone and misoprostol is an established method for induction of early first trimester abortion, but there is no consensus about the best evaluation of treatment outcome. We assessed endometrial thickness, determined by ultrasound and serum-human chorionic gonadotropin (s-hCG) as markers of successful management. METHODS: Prospective trial involving 255 women, with a gestation of 62 days or less, who were to undergo medical abortion. In addition to our established routines of performing clinical and ultrasound examinations, we also determined the s-hCG level prior to treatment and at follow-up. RESULTS: Of the 255 subjects treated during the study, 20 (7.8%) were lost to follow-up. The overall complete abortion rate was 94.0%. Fourteen subjects required vacuum aspiration, nine of them prior to the scheduled follow-up and five thereafter. None of the pregnancies were ongoing. A decrease of 99% in s-hCG levels was noted in 99% of the women, when levels determined prior to mifepristone intake and those measured 15-71 days post-abortion were compared. CONCLUSION: This study confirms that s-hCG levels drop sharply after medical abortion. To assess the completeness of medical abortion, we recommend that clinical examination to be combined with determination of s-hCG. Ultrasonography should be carried out only when indicated.  相似文献   
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BACKGROUND: We have previously shown that experimental strangulation obstruction leads to increased release and concentration of endothelin-1 (ET-1) in venous blood from the strangulated bowel loop. The present study focuses on the microcirculatory effects of the released ET-1 in strangulation obstruction. METHODS: In anesthetized pigs strangulation obstruction was induced by increasing pressure in a baby pressure gasket placed around a loop of ileum until venous pressure reached 45 mm Hg. The pigs were randomly allocated into two groups. The nonselective ET(A)/ET(B) antagonist bosentan was administered intravenously (5 mg kg(-1)) to eight pigs (bosentan group) 30 min before strangulation, which was maintained for 90 min. Another eight pigs were treated in same manner except for the bosentan injection (control group). RESULTS: The concentration of ET in arterial and intestinal venous blood increased markedly after intravenous administration of bosentan. Intravenous infusion of bosentan was followed by a reduction in systemic arterial blood pressure. Bosentan reduced vascular resistance and increased blood flow in the normal intestinal mucosa. It also reduced muscularis blood flow in the beginning of the experiment. In strangulated small bowel bosentan inhibited the increase in vascular resistance usually caused by strangulation obstruction. Muscularis blood flow in strangulated small bowel was not affected by bosentan. CONCLUSION: Endothelin is involved in the normal regulation of arterial blood pressure. The increase in vascular resistance associated with strangulation obstruction is caused mainly by locally released endothelin.  相似文献   
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Prognostic factors in hepatocellular carcinoma (HCC) conventionally consist of staging with the tumour node metastasis system and grading by tumour cellular differentiation. There are also other factors useful in prognostication but most of them are clinical. With new discoveries in the pathobiology of cancers and introduction of new medical technology, pathological and biological factors of HCC in relation to prognosis have been studied quite extensively. Morphological features of the tumour, both gross and histological, have been found to be significantly related to tumour recurrence and patient survival. Recently, applications of new antibodies and techniques have enabled studies on cellular proliferation using different antibodies such as those for proliferating cell nuclear antigen and Ki-67 protein. These studies on cellular proliferation, as well as assessment of argyrophilic nucleolar organizing regions, have been shown to provide good prognostic significance. Flow cytometric studies on DNA ploidy and studies on expression of genes including the p53 gene, hormone receptors and others show less unanimous results in their prognostic significance. The influence of gender on survival is also reviewed. In conclusion, pathological and biological factors are useful and help to guide clinicians in the management of patients and in assessment of long-term prognosis.  相似文献   
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BACKGROUND: It has earlier been shown that increased intra-abdominal pressure (IAP) reduces renal blood circulation and urine output both clinically and experimentally. The aim of this study was to investigate the effect of endothelin-1 inhibition by the endothelin-1 receptor antagonist tezosentan on renal blood circulation and diuresis in pigs subjected to prolonged increased intra-abdominal pressure. MATERIAL AND METHODS: The IAP in domestic pigs was maintained at 30 mmHg for 3 h. One group of 10 animals was pre-treated with the endothelin-1 receptor antagonist tezosentan, and then received continuous infusion of tezosentan throughout the experiment. Another group of 10 animals served as control. We measured renal cortex blood flow, plasma renin activity, blood concentrations of endothelin-1 and aldosterone, and diuresis. RESULTS: The administration of tezosentan to pigs with an IAP of 30 mmHg was followed by reduced arterial pressure, reduced renal cortex blood flow, and reduced diuresis. The plasma renin activity increased markedly, but neither renal vascular resistance nor blood concentration of aldosterone did change significantly. CONCLUSION: Tezosentan reduced the arterial blood pressure, which resulted in decreased renal cortex blood flow, and aggravation of the oliguria usually observed under increased IAP. The plasma renin activity increased, but this was not followed by changes in renal vascular resistance, or blood concentration of aldosterone. The results indicate that drugs, which reduce the arterial pressure, may be harmful to the kidneys under increased IAP.  相似文献   
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In a case of abdominal pregnancy, human chorionic gonadotropin (hCG) was determined twice during the first trimester and serially after removal of the fetus and placenta left in situ. From the 5th to the 7th week of gestation, the hCG values increased, from 5980 to 10000 U/l. After operation the hCG level decreased to 197 U/l after 51 days and hCG was not detectable 72 days postoperatively.  相似文献   
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OBJECTIVES: This study was designed to determine whether therapy with vasodilators and diuretics, designed to normalize loading conditions in decompensated heart failure (HF), reduces neurohormonal activation in the short term. BACKGROUND; Elevated vasoactive neurohormone levels in chronic HF have adverse prognostic impact and may be targeted by specific therapies. METHODS: Endothelin-1, catecholamines, renin, aldosterone, angiotensin and atrial natriuretic peptides (ANP, N-ANP and BNP) were measured in 34 patients with advanced HF before and after hemodynamically guided therapy with vasodilators and diuretics. The therapy was designed to reduce filling pressures and systemic vascular resistance (SVR) without inotropic therapy. Blood was drawn before therapy (A), after initial diuretic and nitroprusside therapy to optimize hemodynamics (B, mean 1.4 days) and after transition to an oral regimen designed to maintain improved hemodynamics (C, mean 3.4 days). RESULTS: Mean pulmonary wedge pressure fell from 31 to 18 mm Hg, right atrial pressure from 15 to 8 mm Hg, and SVR from 1,780 to 1,109 dynes/s/cm(-5). Cardiac index increased from 1.7 to 2.6 l/min/m(2) without intravenous inotropic agents (all p < or = 0.05). Average endothelin levels declined by 30%, from 7.7 to 5.5 pg/ml, and remained low at time point C, 5.2 pg/ml (p < 0.01). Norepinephrine was 858 at time A, 817 at time B, and fell by time C to 608 pg/ml (p < or = 0.05). The mean plasma BNP level fell by 26% after only 1.4 days and by 53% at time C (p < 0.001). CONCLUSIONS: Neurohormonal activation rapidly decreases after short-term therapy tailored to decrease severely elevated filling pressures and SVR without inotropic agents. Therapy designed to address neurohormonal activation should include therapy to improve severe resting hemodynamic compromise.  相似文献   
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Soluble CD23 (sCD23) was proposed as a marker of disease activity and as an important prognostic parameter in B‐cell chronic lymphocytic leukemia (B‐CLL). In this study, prognostic significance of sCD23 in B‐CLL was examined according to its temporal relationship with the known clinical parameters of the disease, CD38 and ZAP‐70. Serum sCD23 levels of 36 B‐CLL patients, followed up in our clinic between 1999 and 2005, and 15 healthy subjects were measured with enzyme‐linked immunosorbent assay. The mean serum sCD23 level of the B‐CLL patients (210.72 ± 193.67 and 6–600 U/ml) was significantly higher than the control group (18.20 ± 14.30 and 6–50 U/ml). Seventy‐eight percent of the B‐CLL patients with lymphocyte doubling time (LDT) <12 months and 24% of patients with LDT >12 months had high sCD23 levels (P = 0.008). Meanwhile, 81% of the patients with diffuse bone marrow infiltration and 33% of patients with nondiffuse infiltration had high levels of serum sCD23 (P = 0.029). A significant difference was found between B‐CLL patients with Binet stages A and C (P = 0.009). Peripheral blood flow cytometry of the patients revealed a significant CD38 expression in patients with high serum sCD23 levels (P = 0.002). Similarly, an increased bone marrow zeta‐chain associated protein kinase‐70 (ZAP‐70) expression was seen in patients with high serum sCD23 levels (P = 0.009, correlation co‐efficient was 0.714). Cumulative and the progression free survivals of the patients with low serum sCD23 levels were 60.1 ± 5.7 months [95% confidence interval (CI); 49.0–71.2] and 51.1 ± 6.6 months (95% CI; 38.0–64.1), respectively. However, they were 43.8 ± 6.5 months (95% CI; 31.0–56.6) and 26.5 ± 6.4 months (95% CI; 14.0–39.1) in patients with high levels. Serum sCD23 is increased in B‐CLL patients and can be used in the clinical follow‐up of the disease in prediction of the tumor mass and prognosis.  相似文献   
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BACKGROUND: The aetiology of pityriasis alba (PA), a common dermatosis in childhood, is still controversial. The objective of this study was to assess the possible aetiopathogenic factors of this disease in infants. METHODS: Forty-four patients with PA and 31 healthy children were examined and compared. Personal hygiene habits, sun exposure, presence of Staphylococcus aureus in nasal fossae and presence of major or minor signs of atopy were assessed during anamnesis and physical examination. Susceptibility to ultraviolet (UV) B radiation was measured by the onset of a contact hypersensitivity reaction to diphenylcyclopropenone in individuals sensitized in previously irradiated areas. RESULTS: The prevalence of PA was higher in individuals with darker skin, in high phototype categories, as well as in males. The number of daily baths and sun exposure between 10.00 h and 15.00 h were significantly higher in the PA group when compared with controls (P = 0.03 and P = 0.0015, respectively). The presence of atopy signs was more common in pityriasis patients (P = 0.002). Susceptibility to UVB radiation was 29.6% in the PA group vs. 29.0% in the control group; nevertheless, important differences were found after stratification in order to control possible confounding factors. The presence of S. aureus in the nostrils was equal in both groups. CONCLUSIONS: Our results confirm that PA, in our population, is more prevalent in males and in individuals in higher phototype categories. In those with inadequate personal hygiene and sun exposure habits the disease is more accentuated, demonstrating that the xerosis presenting in individuals with atopic diathesis is an important element in the development of the disease. S. aureus is not an important aetiopathogenic factor in PA. Susceptibility to UVB becomes important when related to the patient's phototype.  相似文献   
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