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991.
Viral infections of the gastrointestinal tract constitute a major health problem during the first years of life. In addition to causing acute diarrhea, rotaviruses and other enteric viruses may be involved in the pathogenesis of necrotizing enterocolitis and other neonatal enteric diseases. There are several potential methods for the prevention and treatment of gastrointestinal viral infections. Antiviral immune globulins, administered by the parenteral or oral route, might prove useful for the inhibition of intestinal viral replication. Alternatively, specific glycoprotein inhibitors of viral-cell binding might be used to prevent the productive infection of intestinal epithelial cells. In addition, since many enteric viruses require proteolytic enzymes for protein cleavage, protease inhibitors may prove to be effective agents for the inhibition of intestinal viral replication. At this point in time, these methods have proven useful for the inhibition of rotavirus infection in experimental animals. The successful application of these and other methods for the prevention of enteric infections in humans might substantially reduce the morbidity and mortality associated with enteric diseases.  相似文献   
992.
Mammary cell differentiation was measured in lactating pipistrelle bats (Pipistrellus pipistrellus) by assay of key enzyme activities, and by determination of protein and lactose synthesis rates in short-term tissue cultures. By these criteria, mammary cell differentiation did not change significantly with stage of lactation, but depended on the extent to which the gland was filled with milk. Key enzyme activities and in vitro synthesis rates were significantly higher in glands suckled immediately before tissue collection, compared with contralateral glands that were engorged with milk. This indicates that mammary cell differentiation in the lactating bat is regulated locally within each gland by a mechanism sensitive to milk accumulation, to the extent that, unlike other species, this obscures any underlying effect of stage of lactation.  相似文献   
993.
We have investigated the use of the fluorescent exclusion dye propidium iodide as a marker for acutely degenerating cells in vivo, and report here that combined injection of kainic acid and propidium iodide into the lateral cerebral ventricle results in labelling of CA3 pyramidal cells 1 and 6 h after injection. Alternate sections stained with thionin at these early times revealed little evidence of histologically detectable cell damage.  相似文献   
994.
Toxicity of sulphur mustard in adult rat lung organ culture   总被引:2,自引:0,他引:2  
The toxicity of the chemical warfare agent sulphur mustard, (bis-(2-chloroethyl)sulphide, HD), was examined in adult rat lung organ cultures. Assessment of HD-induced damage by the MTT cytotoxicity assay indicated that the median lethal concentration (LC50) of HD in these cultures was reproducible, and in the μM range. Damage to the lung slices was expressed only after a latent period of 48 h and did not increase significantly with longer expression times. Histopathological examination of HD-treated lung cultures showed that the structural changes in the lung tissue paralleled the toxicity measured biochemically, and were also similar to the damage found in animals and man exposed to HD in vivo. This in vitro model offers a useful tool with which to study the toxicity and mechanism of action of sulphur mustard.  相似文献   
995.
ABSTRACT. Of twenty-five healthy, full term infants without a family history of atopic diseases, 13 were exclusively breast-fed from birth for a minimum of 3½ months (median 4½ months), whereas the remaining 12 infants were fed with cow's milk-based formulas from birth for a minimum of 4 months. In the latter group of children a significant increase in serum IgE as well as in salivary IgA was found. In infants exclusively breast-fed, no increase in serum IgE was seen until 6 months of age; at nine months of age, salivary IgA was still significantly lower than in the infants fed cow's milk-based formulas. No children developed obvious allergic diseases during the first three years of life. Thus, cow's milk proteins given to newborn children of non-atopic mothers did not seem to increase the risk of IgE-mediated diseases, maybe due to the development of "blocking" IgA-antibodies in the alimentary tract.  相似文献   
996.
997.
998.
The study aims were to review the clinical features of a group of patients with Noonan syndrome and to further elucidate their bleeding tendency. Eighteen patients (12M, 6F) aged 2.6–13.3 years underwent a clinical assessment, a questionnaire of their bleeding tendency and laboratory coagulation studies. Nine had cyanotic spells or breathing difficulties after birth; 11 had poor feeding or weight gain. Increased bruising or bleeding was reported in 12 (67%), four of whom had bleeding from the oral cavity. Excessive bleeding was not reported from operative procedures in other sites. Partial thromboplastin time was prolonged in 10 (56%) associated with low levels of clotting factors, particularly XI and XII. Bleeding times were normal; one had marginal thrombocytopenia. Coagulation results did not correlate with bruising history and may not predict bleeding risk. Care is required when Noonan syndrome patients undergo surgery, particularly of the oropharynx, with immediate availability of suitable blood products.  相似文献   
999.
This article describes the current indications, contraindications, and results of shoulder fusion. The preferred position, AO technique, and complications are described.  相似文献   
1000.
We present the results of 38 children with leg inequality treated by circumferential periosteal release. Leg-length discrepancy was expressed as a percentage of the longer limb. All patients showed a decrease in percentage difference at one year after operation, the mean difference dropping from 7.24% to 5.45%. The size of the response was directly related to the age of the patient at operation, being more pronounced in the younger patients. The response was not related to sex, diagnosis, or rate of growth of the patient immediately preceding operation.  相似文献   
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