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Severe aortic regurgitation was discovered in a young man 21 days after blunt chest trauma and after a prolonged febrile state with positive blood cultures. Using transoesophageal echocardiography (TEE), it was possible to make the differential diagnosis between traumatic rupture and endocarditis as the cause of valvular insufficiency. The use of TEE in the initial evaluation of severe thoracic trauma with an unclear clinical picture is recommended. This method is easy to use at the bedside and gives precise information on the aortic valve and the ascending aorta.  相似文献   
13.
Cellular changes were immunocytochemically characterized in skin vessels of five patients with idiopathic generalized racemose livedo (Sneddon's syndrome), and one patient with localized racemose livedo associated with essential thrombocythaemia. Antibodies against α-smooth muscle-actin, tropomyosin, desmin, vimentin, factor VIII-related antigen, human endothelial cells (CD31), human macrophages (CD68), and HLA-DR positive cells (CR3/43) were used. Conventional light microscopy showed, in all cases, intimal thickening of ascending arteries and arterioles as a result of an accumulation of cells and extracellular hyalinized material. None of the specimens showed infiltration with polymorphonuclear leucocytes or macrophages. The cells in the region of the intimal hyperplasia showed intense positive immunostaining for α-smooth muscle actin and tropomyosin. Staining for the intermediate filament desmin was localized to the resident smooth muscle cells of the media, whereas staining for vimentin was found in all types of cells in both the intima and media. Positive immunostaining for factor VIII-related antigen and CD31 was strictly confined to the endothelial cells lining the narrowed lumina of the vessels. No positive staining with either antibody was observed in totally occluded vessels. Cells in the subintimal space did not show reactivity for CD68 in any of the specimens, but two cases showed solitary cells with positive staining for HLA-DR in this region. There were no differences in staining pattern between Sneddon's syndrome and essential thrombocythaemia with any of the antibodies. Our results support the assumption that the ‘intimal proliferation’ in both diseases is caused by colonization of the subendothelial space with contractile cells of possibel smooth muscle origin. The similarities in histopathology and immunocytochemistry might indicate that in both diseases platelet-derived factors play a causative role.  相似文献   
14.
C F Saladino  Q Yeh  E Zimmer  E A Jonas 《Artery》1992,19(2):76-93
This study shows that arterial smooth muscle cells (SMC) isolated from rats receiving atherogenic doses of the lipid emulsion, Lipofundin-S, alter their in vitro growth properties. Compared to cells from control animals, SMC isolated from Lipofundin-S-infused rats show a reduction in both saturation density and response to increasing serum concentrations, without a change in the baseline proliferation. Also, SMC isolated from lipid-treated animals and grown for five days in the presence of 30, 150, or 300 pg/ml estradiol show a 30% increase in growth vs. cells from controls. Epinephrine at 1 microM stimulates growth in SMC from control rats, while causing no growth enhancement over five days in cells from lipid-infused animals. Thus, atherogenic infusions of Lipofundin-S into rats cause phenotypic changes in arterial SMC which can be passed to successive cell generations in vitro.  相似文献   
15.
Clinical and histological patterns of dermatofibromas of the nail apparatus   总被引:1,自引:0,他引:1  
True fibromas develop as painless slow-growing nodular tumours. They may appear in any portion of the nail apparatus. The clinical features vary according to their anatomical site. In contrast, the histological features, consisting of a dermal hypocellular reticular nodule with ill-defined demarcation, were similar in all our patients, and factor XIIIa was negative.  相似文献   
16.
BACKGROUND AND PURPOSE: Uterine cramping pain is related to prostaglandins, which are mediated by cyclooxygenase. However, it is unknown whether the analgesic effects of the non-selective cyclooxygenase inhibitor tenoxicam are different between primiparous and multiparous women. This placebo-controlled, double-blind study compared the analgesic effect of tenoxicam on post-cesarean uterine cramping pain in primiparous and multiparous women. METHODS: Forty primiparous women and 40 multiparous women who were scheduled for elective cesarean delivery were allocated into the following 4 groups: saline-primipara (SP) group, tenoxicam-primipara (TP) group, saline-multipara (SM) group, and tenoxicam-multipara (TM) group. Saline or 20 mg tenoxicam was intravenously injected immediately after clamping of the umbilical cord. All patients received patient-controlled analgesia for postoperative pain control. Resting wound pain, uterine cramping pain, morphine consumption, and morphine-related side effects were evaluated at 4 and 24 hours after surgery. RESULTS: At 24 hours after surgery, tenoxicam-related relief of uterine cramping pain was 2.1 in primiparous women (visual analog scale: SP 5.6 (4.4-6.8) minus TP 3.5 (2.2-4.9); p < 0.01). The tenoxicam-related morphine-sparing effect was 14 mg (45%) in primiparous women (SP 31.4 mg (23.9-38.8) minus TP 17.4 mg (11.6-23.2); p < 0.01). The tenoxicam-related relief of uterine cramping pain and tenoxicam-related morphine-sparing effect were not significant in multiparous women. CONCLUSIONS: This study revealed that the analgesic effect of tenoxicam on post-cesarean uterine cramping pain is greater in primiparous women than in multiparous women. Further studies are required to determine whether a higher dosage of tenoxicam is beneficial to reduce uterine cramping pain in multiparous women.  相似文献   
17.
Factors associated with hypertension in Nigerian civil servants   总被引:3,自引:0,他引:3  
BACKGROUND. Study of hypertension in segments of West African populations in transition toward Westernization may lead to better understanding of the high risk for hypertension among Westernized blacks. METHODS. Five hundred fifty-nine urban civil servants, ages 25-54, were recruited from six ministries of Bendel State, Nigeria. Blood pressure, physical measurements, urinary protein and glucose, fasting blood glucose, and demographic data were collected at the workplace. Subjects were classified as senior staff (professionals or administrators) or junior staff (non-administrators). RESULTS. Among 172 male senior staff, the age-adjusted rate of hypertension (diastolic blood pressure > or = 90 mm Hg, systolic blood pressure > or = 140 mm Hg, or on an antihypertensive medication) was 43% and occurrence rose dramatically from 21 to 63% across age groups 25-34 to 45-54, respectively. Among 266 male junior staff, the age-adjusted rate of hypertension was 23%, and occurrence did not rise with age. Logistic regression showed that body mass index (kg/m2), age, alcohol drinking, and being senior staff were all independently related to hypertension in men. On the other hand, the age-adjusted rate of hypertension in 121 women was 20% and was significantly related only to body mass index. CONCLUSION. Male urban civil servants appeared to have a risk for hypertension similar to that of U.S. black males. Age, body mass index, alcohol drinking, and other unidentified factors related to higher socioeconomic status were strong determinants of hypertension in this population.  相似文献   
18.
This study, evaluating the effects of hyperthyroidism (HT) in oesophageal motility, depended on an oesophageal radionuclide transit test. A modified standard method was used to calculate: (a) total mean transit time (MTT), (b) residual fraction (RF) and (c) retrograde index (RI) in a supine position. Eighteen untreated patients with HT and 25 normal volunteers (NV) with a similar age distribution were included in this study. The results showed that oesophageal motility in patients with HT was worse than in the normal controls (P < 0.05 by Student's t-test). The correlation of MTT, RF and RI with size and function of thyroid glands in the patients with HT were calculated to explain the effects of HT in oesophageal motility. The results showed that neither the size nor the function of the thyroid glands in HT affected oesophageal motility.  相似文献   
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20.
The ability to cluster different perfusion compartments in the brain is critical for analyzing brain perfusion. This study presents a method based on a mixture of multivariate Gaussians (MoMG) and the expectation-maximization (EM) algorithm to dissect various perfusion compartments from dynamic susceptibility contrast (DSC) MR images so that each compartment comprises pixels of similar signal-time curves. This EM-based method provides an objective way to 1) delineate an area to serve as the in-plane arterial input function (AIF) of the feeding artery for adjacent tissues to better quantify the relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF), and mean transit time (MTT); 2) demarcate regions with abnormal perfusion derangement to facilitate diagnosis; and 3) obtain parametric maps with supplementary information, such as temporal scenarios and recirculation of contrast agent. Results from normal subjects show that perfusion cascade manifests (in order of appearance) the arteries, gray matter (GM), white matter (WM), veins and sinuses, and choroid plexus mixed with cerebrospinal fluid (CSF). The averaged rCBV, rCBF, and MTT ratios between GM and WM are in good agreement with those in the literature. Results from a patient with cerebral arteriovenous malformation (CAVM) showed distinct spatiotemporal characteristics between perfusion patterns, which allowed differentiation between pathological and nonpathological areas.  相似文献   
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