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941.
The Inter-Regional Epidemiological Study of Childhood Cancer (IRESCC) collected interview and medical information relating to the child's past medical experiences from parents of 555 children diagnosed with cancer and parents of 1110 unaffected matched controls. No significant associations emerged overall for ante-natal care, place and mode of delivery, length of gestation, birth weight, condition at birth, special care, neonatal procedures or breast-feeding. Few risk factors relating to previous illnesses and medication were found, although increasing numbers of illnesses appeared to be associated with an increased risk of childhood cancer, particularly acute lymphoblastic leukaemia. A highly significant excess of case children had not been immunised (p = 0.005). In general, these results indicate that past medical experiences have little influence on the development of cancer in children.  相似文献   
942.
A mouse model of pulmonary tuberculosis induced by the intratracheal instillation of live and virulent mycobacteria strain H37-Rv was used to examine the relationship of the histopathological findings with the local kinetics production and cellular distribution of tumour necrosis factor-alpha (TNF-alpha), interleukin-1 alpha (IL-1 alpha) and transforming growth factor-beta (TGF-beta). The histopathological and immunological studies showed two phases of the disease: acute or early and chronic or advanced. The acute phase was characterized by inflammatory infiltrate in the alveolar-capillary interstitium, blood vessels and bronchial wall with formation of granulomas. During this acute phase, which lasted from 1 to 28 days, high percentages of TNF-alpha and IL-1 alpha immunostained activated macrophages were observed principally in the interstium-intralveolar inflammatory infiltrate and in granulomas. Electron microscopy studies of these cells, showed extensive rough endoplasmic reticulum, numerous lysosomes and occasional mycobacteria. Double labelling with colloid gold showed that TNF-alpha and IL-1 alpha were present in the same cells, but were confined to separate vacuoles near the Golgi area, and mixed in larger vacuoles near to cell membrane. The concentration of TNF-alpha and IL-1 alpha as well as their respective mRNAs were elevated in the early phase, particularly at day 3 when the bacillary count decreased. A second peak was seen at days 14 and 21-28 when granulomas appeared and evolved to full maturation. In contrast, TGF-beta production and numbers of immunoreactive cells were low in comparison with the advanced phase of the disease. The chronic phase was characterized by histopathological changes indicative of more severity (i.e. pneumonia, focal necrosis and extensive interstitial fibrosis) with a decrease in the TNF-alpha and IL-1 alpha production that coincided with the highest level of TGF-beta. The bacillary counts were highest as the macrophages became large, vacuolated foamy cells, and containing numerous bacilli with immunoreactivity to mycobacterial lipids and lipoarabinomannan (LAM). These macrophages displayed poor and scarce TNF-alpha and IL-1 alpha immunostaining but still strong immunoreactivity to TGF-beta. These cytokine production kinetics and the spatial relationship between immunostained cells and lung lesions corroborate the important role of TNF-alpha and IL-1 alpha in the constitution of granulomas and immune protection during the early phase of the infection, and also suggest an important if not primary role for TGF-beta in the immunopathogenesis of the advanced forms of pulmonary tuberculosis.  相似文献   
943.
944.
Thirty-two castrated male crossbred growing pigs (average initial wt 26.9 kg) were used to determine the effect of a high level of dietary protein (37%) compared with a normal level of protein (15%) on enterobacteria and Campylobacter sp. inhabitation in the large intestine and on visceral organ hypertrophy and the interrelationships between these two factors. Pigs were kept in pairs (eight pens of two pigs/diet) and fed their respective diets and libitum. Eight pigs (two pens of two pigs fed each diet) were killed at wk 4, 8, 12 and 16 without fasting. Fecal samples were obtained every 2 wk from animals scheduled for necropsy at 16 wk, and colon contents were obtained from all pigs at necropsy; samples were enumerated individually for enterobacteria and Campylobacter sp. Weights of heart, lungs, liver, kidneys, perirenal fat and empty stomach, small intestine and large intestine were recorded at necropsy. Stomach, cecum and proximal colon were sectioned for histopathologic examination. Daily body weight gain was depressed by high dietary protein, but liver and kidneys were heavier in the high protein group than in controls at each time interval. Mild lymphoid hyperplasia of Peyer's patches in the small intestine in some pigs in both groups was indicative of antigenic stimulation but not of pathologic significance. There was no effect of diet on counts of enterobacteria or Campylobacter sp. in feces or colon contents during the 16-wk experiment. We conclude that the hypertrophic response of the tissues of growing pigs to high dietary protein is not the result of the presence of Campylobacter sp. or enterobacteria in the colon contents.  相似文献   
945.
The authors discuss the results of application of proteinase preparations immobilized on a water soluble carrier (Immozymase) and a water insoluble carrier (Profezyme) in the management of ++pyo-necrotic processes of various etiology and localization in 1,059 patients. The wounds were cleansed 1.5-2 times quicker than with the traditional methods of treatment. Immobilized proteinases possessing a prolonged therapeutic effect were found to stimulate the regeneration process. The authors believe the use of Immozymase to be promising in the treatment of purulent foci which are drained with difficulty and in intracavitary administration for treating purulent processes in the thoracic or abdominal cavity.  相似文献   
946.
947.
948.
The kinetics of inhaled methyl ethyl ketone (MEK) at a concentration of 200 ppm for four hours were studied in volunteers after swallowing ethanol at a dose of 0.8 g/kg. Ethanol was given either before or at the end of the exposure to MEK. The blood concentrations of MEK, 2-butanol, and 2,3-butanediol were monitored during and after the exposure. MEK concentrations in exhaled air and MEK and 2,3-butanediol concentrations in urine were also measured. Ethanol inhibited the primary oxidative metabolism of MEK and caused an increase in the blood concentrations of MEK and 2-butanol after ingestion. Ethanol ingestion, through higher blood MEK concentrations, also increased the elimination of MEK in the urine and exhaled air. Ethanol taken before exposure to MEK reduced the serum concentration of 2,3-butanediol initially but there was an increase about eight hours after the exposure. Urinary excretion of 2,3-butanediol followed the same pattern. Prior ingestion of ethanol thus seemed to interfere with the metabolism of 2,3-butanediol during and after exposure to MEK.  相似文献   
949.
During the diagnostic evaluation of patients with vasculogenic impotence duplex scanning has been proposed as a reliable noninvasive method to evaluate the cavernous arteries. However, the sensitivity and specificity of this test have never been elucidated. To provide insight into the clinical value of this test 25 men who presented with impotence and failed to respond to 60 mg. intracavernous papaverine were evaluated with duplex scanning and the results of this modality were compared to penile angiography. The cavernous arteries were considered normal by duplex scanning if the artery demonstrated either a 60% or greater increase in diameter and/or a peak flow velocity of greater than 25 cm. per second 5 minutes after papaverine injection. Penile angiography was considered normal if both cavernous arteries were visualized and appeared to be normal radiographically (after intracorporeal papaverine). In the 25 patients studied there was no significant difference in peak flow velocity between patients with normal or abnormal cavernous arteries by angiography. In addition, arterial dilatation (more than 60%) after papaverine injection did not correlate with the results of the angiogram. These data demonstrate that duplex scanning of the cavernous arteries does not correlate well with what is observed by penile angiography in a selected population of men with vasculogenic erectile dysfunction. Since penile angiography itself has limitations in the evaluation of the penile arteries, the reliability of duplex scanning to identify cavernous artery dysfunction needs additional confirmation.  相似文献   
950.
Indications for relaparotomy   总被引:2,自引:0,他引:2  
From 1980 to 1987, 10,446 patients were operated on. In 152 patients, the necessity of a repeated operative intervention arose. In 106 patients the emergency, in 42--delayed, and in 4--elective relaparotomies were performed. There were the following indications for relaparotomy: diffuse and circumscribed peritonitis (78 patients), ileus (46), eventration (11), hemorrhage (12), others (5). Diagnosis of postoperative complications requiring relaparotomy is difficult. The postoperative lethality was 26%.  相似文献   
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