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The activity of various enzyme groups and the levels of protein and glycogen in the peritoneal macrophages of CBA mice treated intraperitoneally with sodium nucleinate were determined histochemically with the use of cytophotometry. A significant increase in the activity of the lysosomal enzymes, such as acid phosphatase and nonspecific esterases and an increase in the activity of lactate, malate, glutamate, alpha-glycerophosphate, and beta-hydroxybutyrate dehydrogenases. NAD.H- and NADF.H-diaphorases accompanied by an increase in the level of the total protein and glycogen were observed. Analysis of the changes was indicative of an increase in the inherent physiological metabolic and functional level under the effect of sodium nucleinate. It is suggested that the macrophage sub-populations with an increased metabolic activity appeared in the peritoneal exudate of the stimulated animals. Participation of the host low molecular DNA in the maintenance of the physiological level of th nonspecific antiinfectious resistance is suggested.  相似文献   
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The fibrosis and scar formation that characterize adult wound healing are also the cause of clinical problems; scar contracture, hypertrophic scar, and pulmonary and hepatic fibrosis are only a few examples. Studies of fetal wound healing can provide an insight into the initiation and regulation of a scarless repair process akin to regeneration. Studies of fetal repair have already suggested mechanisms that might favorably alter adult healing. Topical application of hyaluronic acid to wounds in adult diabetic rats leads to enhanced epithelial migration. It has been recognized that the addition of TGF-beta to fetal wounds causes an adultlike healing response with fibrosis and inflammation. A subsequent study using neutralizing antibody to TGF-beta in adult wounds showed enhanced healing with a more normal dermal architecture with fewer macrophages, fewer blood vessels, and less collagen. As our understanding of regenerative tissue repair increases, the opportunities to modulate adult fibrotic conditions should expand.  相似文献   
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Sotos syndrome is included among the overgrowth disorders, most of which have an increased risk of neoplasms. Sotos syndrome does not appear to be related to a specific tumor type, but rather to the development of solid tumors of ectodermal or mesodermal origin in general. We report on two Sotos syndrome patients who developed a non-Hodgkin lymphoma and an acute lymphoblastic leukaemia, respectively. Our experience suggests that there may exist a high frequency of lymphoproliferative disorders in Sotos syndrome, and points out the importance of a long-term follow-up of Sotos syndrome patients, to detect a possible neoplastic evolution.  相似文献   
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A two-part prospective study of adverse drug reactions (ADRs) in Indian children was carried out at a teaching general hospital. Using an in-hospital intensive surveillance scheme (IISS) for the detection of ADRs, indoor patients of one of the two units in the pediatric ward were monitored daily for 6 months, with the other unit serving as a control group. A total of 347 patients were monitored, 2781 daily orders written and 24,474 doses of 96 different drugs given. Six patients suffered from ADRs (1.73%), and 1 reaction proved fatal (0.29%), while the control group reported only 1 ADR in the same time period. The frequency of ADRs (p < 0.001) and their resultant mortality in Indian children was less than that in a western prototype study. Though IISS showed a marked increase in ADR reporting, it was too cumbersome for routine use in our country. In the second part of the study, 40 cases of ADRs seen over 2 years were analyzed. Antimicrobials, especially sulphonamides, accounted for a high percentage of cases mostly as skin rashes and fairly severe reactions were common. Patients on anti-tuberculous and anti-convulsant drugs required prolonged supervision for late onset reactions.  相似文献   
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Protection of Metals and Physical Chemistry of Surfaces - A method for depositing electroactive coatings based on conductive polymers on a graphite foil has been developed. The electrochemical...  相似文献   
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Protection of Metals and Physical Chemistry of Surfaces - Composite electroactive coatings (CEACs) are prepared on the basis of polyaniline (PANI) and manganese compounds (MnOx) by potentiodynamic...  相似文献   
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The issue of how human immunodeficiency virus-1 (HIV-1) enters the body following sexual contact has been the subject of considerable controversy. Several possible routes for the initial infection have been suggested [1-6], including the possibility that the transmission is mediated by HIV-1-infected lymphocytes or macrophages in serum and female genital tract secretions, rather than by free virus. We recently reported that HIV-1-infected, activated primary monocytes can migrate between epithelial cells grown in confluent monolayer cultures in vitro [7]. We report here on experiments carried out in mice to test the hypothesis that mononuclear blood cells are capable of migrating through intact epithelia, and thus of carrying a virus into an animal. We placed double-stained, activated mononuclear blood cells into the vaginas of mice; four hours later, numerous double-stained cells were observed in the connective tissue beneath the vaginal epithelium and the iliac lymph nodes of the experimental mice. We speculate that such migration may be involved in the sexual transmission of HIV-1.  相似文献   
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