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2.
Reviewing 5 recent cases, different anatomical and clinical forms of partial or complete urachal persistency are described: patent urachus, urachal cyst, urachal sinus and urachal diverticulum. The risk of late malignant evolution of this embryonic vestige justifies radical surgical removal at time of diagnosis.  相似文献   
3.
The present study applies a non-invasive method to the quantitative evaluation of left ventricular stiffness in normal subjects and in patients with ischaemic heart disease (IHD). We have studied 20 patients with IHD and 25 healthy subjects. The third heart sound (S3) was detectable in all patients. We have correlated the energy spectrum of S3, divided into 15 Hz bands, with a series of echocardiographic parameters. The existence of a significant correlation between the spectrum energy and the diameter and thickness of the left ventricle at the moment of S3 allowed us to explore the possibility of interpreting the origin of S3 based on a mathematical model. Our hypothesis has been that, once the left ventricle starts vibrating, it behaves as a simple physical model composed of a mass and an elastic element. To this purely elastic model one can add a factor accounting for viscosity, with a damping effect, to obtain a more complex viscoelastic model. The stiffness coefficient 'k' was computed in both models from the peak frequency of S3 and the left ventricular mass at the moment of S3. Furthermore, in the viscoelastic model, the damping element 'c' was also computed. Both parameters--k and c--were significantly increased in the group with IHD compared with the control group. Although a simplification of the vibrating system, these models make it possible to obtain non-invasively information on the characteristics of the left ventricle through the combined use of echocardiography and spectral analysis of S3.  相似文献   
4.
Fifty-nine epidemiologically unrelated methicillin-resistant Staphylococcus aureus (MRSA) isolates from different geographical areas and 23 phage-type 77 MRSA isolates from France were investigated. Cellular DNA, digested with restriction endonucleases EcoRI or HindIII, was probed with plasmids carrying the gene encoding 16S rRNA (pBA2), the gene aacA-aphD (pSF815A) and the gene aacA-aphD plus part of IS256 (pIP1307). When probed with pBA2, most of the unrelated isolates displayed the same hybridisation pattern. A greater diversity in patterns was detected in gentamicin-resistant strains with the two other probes. The most accurate fingerprinting of these isolates was obtained with the probe pIP1307. Moreover, this probe appeared to be useful for tracing the phage-type 77 epidemic MRSA isolates widespread in French hospitals.  相似文献   
5.
Plasma protein fraction (PPF) contaminated by factor XII active fragment (XIIf) may cause hypotensive reactions when infused to patients. This study was planned to assess in conscious normotensive rats whether the blood pressure response to the factor XIIf is mediated by an activation of the plasma kallikrein-kinin system or by stimulation of prostaglandin synthesis. To test whether the factor XIIf-induced blood pressure fall is due partially to an enhanced generation of vasodilating prostaglandins, the blood pressure effect of XIIf (1 microgram i.v.) was investigated 15 min after treatment with indomethacin (5 mg i.v.), an inhibitor of cyclo-oxygenase. Factor XIIf reduced mean blood pressure similarly in indomethacin- and vehicle-treated rats (-23 +/- 4 mmHg, n = 5, and -23 +/- 5 mmHg, n = 4, respectively). Other rats received factor XIIf 15 min after depletion of circulating prekallikrein by the administration of dextran sulfate. Thirty minutes after a 0.25 mg i.v. dose of this agent, plasma prekallikrein activity averaged 0.12 +/- 0.015 mumol/min/ml (n = 6) as compared to 2.48 +/- 0.31 mumol/min/ml in control rats (n = 4, P less than .001). Factor XIIf decreased mean blood pressure by only 4 +/- 2 mm Hg in rats pretreated with dextran sulfate. Thus, it was possible to blunt the acute hypotensive effect of factor XIIf by depleting circulating prekallikrein, but not by inhibiting prostaglandin production. This strongly suggests that the blood pressure effects of factor XIIf is mediated by a stimulation of the plasma kallikrein-kinin system.  相似文献   
6.
OBJECTIVE: To assess the extent of nosocomial transmission of tuberculosis among infants, family members, and healthcare workers (HCWs) who were exposed to a 29-week-old premature infant with congenital tuberculosis, diagnosed at 102 days of age. DESIGN: A prospective exposure investigation using tuberculin skin test (IST conversion was conducted. Contacts underwent two skin tests 10 to 12 weeks apart. Clinical examination and chest radiographs were performed to rule out disease. Isoniazid prophylaxis was administered to exposed infants at higher risk. SETTING: A neonatal intensive care unit in an urban hospital in Brussels, Belgium. PARTICIPANTS: Ninety-seven infants, 139 HCWs, and 180 visitors. RESULTS: Newly positive TST results occurred in HCWs who had been in close contact with the infant. Six (19%) of 32 primary care nurses and physicians had TST conversions and received treatment. Among the 97 exposed infants, 85 were screened and 34 were identified as at higher risk of infection. Of these, 27 received preventive isoniazid. None of the infants and none of the 93 other infants' family members evaluated were infected. CONCLUSIONS: Congenital tuberculosis in an infant poses a risk for nosocomial transmission to HCWs. Delayed diagnosis of this rare disease and close proximity are the most important factors related to transmission.  相似文献   
7.
Parathyroid hormone-related protein (PTHrP) plays an important role in the pathogenesis of malignant hypercalcemia by stimulating bone resorption and/or renal tubular reabsorption of calcium. In cultured cancer cells, its production can be influenced by various factors or ions, but the regulation of its production is still poorly understood. We investigated the effects of stimulators of cAMP synthesis on PTHrP release by a human lung squamous-carcinoma cell line (BEN). In supervised cells grown on microcarrier beads, PTHrP production was significantly increased after incubation with calcitonin for only 20 min. The release of immunoreactive and bioactive PTHrP was increased by incubating the cells with forskolin, 3-isobutyl-I-methylxanthine or dibutyryl cAMP even in the presence of the protein-synthesis inhibitor cycloheximide for 6 hr. The calcitonin-mediated stimulation was not accompanied by. concomitant changes in PTHrP mRNA. The microfilament-disrupter cytocha-lasin D was shown to enhance the basal and calcitonin-induced production of PTHrP. These results indicate that stimulators of cAMP synthesis enhanced PTHrP release by BEN cells.  相似文献   
8.
The authors present a case of transitional cell carcinoma of the renal pelvis with inferior vena cava involvement. Two types of vena cava involvement are discussed: thrombus or nodes. The CT scan appears to be the best examination to preoperatively diagnose the type of invasion in order to be able to select the optimal treatment. However, these two types of involvement have a poor prognosis and surgery abstention may be justified. Chemotherapy may be useful in these cases.  相似文献   
9.
Breast and cervical cancer surveillance, United States, 1973-1987.   总被引:3,自引:0,他引:3  
Breast and cervical cancer incidence and mortality rates were reviewed for the period 1973-1987. For breast cancer, mortality has been relatively stable, increasing from 26.9/100,000 women in 1973 to 27.1 in 1987. Alternatively, data from the National Cancer Institute's Surveillance, Epidemiology, End Results Program (SEER) showed a 36% increase in the incidence of this malignancy over the same period. In 1987, overall incidence of invasive breast cancer was 111.9/100,000 women. White women experienced lower overall mortality rates and higher overall incidence than black women; however, these differences varied by age. Examination of breast cancer incidence by stage of disease at diagnosis revealed that rates for distant and regional disease have remained relatively stable since 1973. In contrast, rates of localized and in situ cancers exhibited an increase in the 1980s that may correspond to increased use of mammography in this country. The rate of decline in cervical cancer incidence and mortality has slowed in recent years. In 1987, 3.0 cervical cancer deaths/100,000 women occurred. SEER incidence for invasive disease for that year was 8.2/100,000. Rates varied by race, age, state, and stage of disease. In general, black women experienced much higher incidence and mortality from invasive cervical cancer than white women. For both races, rates of in situ disease were highest among young women and decreased rapidly with age. Rates of in situ cervical cancer were consistently higher than rates of invasive cancer for the time period studied.  相似文献   
10.
Macrolides     
The first macrolides were marketed almost 30 years ago. These drugs constitute a homogeneous class of antibiotics with very similar mechanisms of action and resistance. Owing to their specific antibacterial spectrum and their mild side-effects, interest in macrolides has now been renewed, notably because of their activity against bacteria that develop within cells. Recent studies have provided additional information on their pharmacokinetic profiles, and notably on their tissue and intracellular distribution.  相似文献   
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