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61.
We studied 3592 Swedish schoolchildren, 8 or 9 years old, examined for palpable submandibular, cervical and supraclavicular lymph nodes. All children were skin tested with 2 TU PPD RT23 and with 0.1 μ g of Mycobacterium avium sensitin or 0.1 μ g of M. scrofulaceum sensitin. A total of 991 children had palpable lymph nodes in any of the three locations. Among them, 811 had lymph nodes in one location, 162 in two locations and 18 in three. In 312 children, the lymph nodes were ± 5 mm in size in any location. The most common location was submandibular. Boys had a significantly higher prevalence of palpable lymph nodes than girls. There was also seasonal variation. Children infected by atypical mycobacteria (sensitin reaction ±6 mm) did not have a higher prevalence of palpable lymph nodes than those not infected.  相似文献   
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The first diagnostic cordocentesis was performed in our unit in October 1985, our 2-year experience is reported. 144 samplings were performed in 137 patients (139 fetuses - 2 patients had twin pregnancies) during gestational weeks 14 to 42. The first attempt was successful in 80% of the procedures, 4 samplings failed. There were no fetal deaths within 3 days after diagnostic cordocentesis, a transient fetal bradycardia was observed in 12.2% of the cases, bleeding occurred in 13.6% of the cases. The indications for cordocentesis were: risk of fetal infection, karyotyping, hemophilia A, alloimmunisation, search for paternity, assessment of fetal acid-base status. Our data confirm that cordocentesis is a safe and reliable diagnostic procedure providing guidelines for management of the pregnancy.  相似文献   
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Accurate assessment of ventricular muscle contractile function in patients with heart disease is impaired by alterations in afterload, preload and wall thickness which often accompany the disease. The relationship between pressure and volume at end systole is considered to provide a contractile index which is independent of preload and which accounts for afterload. Use of the index prerequisites determinations of the left ventricular end systolic pressure, wall thickness as well as the dimensions or volumes, respectively, which may be assessed with either invasive or noninvasive methods. In patients with aortic stenosis and congestive heart failure, there was a significantly reduced slope (0.9 +/- 0.5) of the end systolic stress-volume relationship as compared with healthy subjects (5.8 +/- 1.3) or patients with aortic stenosis without congestive heart failure (3.9 +/- 1.3), while the ejection fraction showed no significant differences. In patients with mitral regurgitation with no or only minimal symptoms postoperatively, preoperatively the end systolic index (ESS/ESVI) was higher (3.3 +/- 0.4) than in patients with marked symptoms postoperatively or those who died perioperatively (2.2 +/- 0.2) and the values of both patient groups were lower than those of normals. In contrast, the values for ejection fraction among the normals and both groups of patients showed substantial overlap. In patients with aortic insufficiency and congestive heart failure, as opposed to patients with aortic insufficiency and only slight symptoms, there was a significantly compromised ejection fraction as well as diminished end systolic index (ESS/ESVI). Patients with hypertension accompanied by congestive heart failure had a significantly diminished slope of the relationship between end systolic left ventricular stress and volume while the values for hypertensive patients without congestive heart failure were within normal limits; in both groups of patients, the ejection fraction was normal. In patients with mitral stenosis, the end systolic index at 5.28 +/- 0.53 did not differ significantly from that of healthy subjects at 4.87 +/- 0.53, while the velocity of circumferential fiber shortening was diminished. Patients with large atrial septal defects and symptoms of congestive heart failure did not differ with respect to end systolic index or ejection fraction as compared with atrial septum defect patients without symptoms. In children with aortic stenosis and high pressure gradients, there was an increased ejection fraction together with a normal end systolic index.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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The object of this study was to evaluate the toxicity of norbornene fluoroalcohol (NBFOH), which is used as an intermediate in the production of fluorinated monomers and polymers. NBFOH was evaluated for acute oral, dermal, and inhalation toxicity, dermal sensitization using the Local Lymph Node Assay (LLNA), mutagenesis by the Ames assay, and subchronic toxicity in a 4-week inhalation rat study. NBFOH demonstrated slight acute toxicity in oral, dermal, and inhalation studies. Approximate lethal doses of 3400 and > 5000 mg/kg for the oral and dermal routes, respectively, and an approximate lethal concentration of 4300 mg/m(3) were determined. NBFOH demonstrated moderate skin irritation, was a severe eye irritant, produced dermal sensitization, but did not cause bacterial mutagenicity either in the presence or absence of S9 activation. Male and female rats were exposed nose only to airborne NBFOH at levels of 0, 410, 1400, and 1500 mg/m(3), 6 h/day, 5 days/week for 4 weeks with clinical and histopathology specimens collected 1 day after the final exposure. Due to the vapor pressure of NBFOH, the 1500 mg/m(3) atmosphere was 27% aerosol and 73% vapor; the 1400 mg/m(3) atmosphere was 5% aerosol and 95% vapor, and the 410 mg/m(3) level was only vapor. No test substance-related mortality or clinical signs of toxicity were observed over the course of the study, and male rats demonstrated significant weight loss and decreased food consumption at 1400 mg/m(3). Male rats from the 1500 mg/m(3) group demonstrated an 11% increase in prothrombin time that was significantly higher than the control value. Examination of fluoride in the urine did not demonstrate a concentration-response relationship, with minimal elevations observed in male rats at all exposure levels and sporadic increases in females. Both male and female rats exposed to 1400 mg/m(3) or greater had squamous metaplasia of the laryngeal mucosa and degeneration of the nasal olfactory and respiratory mucosa. Based on the above findings, NBFOH demonstrates the potential to produce allergic contact dermatitis, and subchronic inhalation studies indicate a no-observed-adverse-effect-level (NOAEL) of 410 mg/m(3).  相似文献   
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