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排序方式: 共有10000条查询结果,搜索用时 80 毫秒
971.
S Trottier K Stenberg I A Von Rosen C Svanborg 《The Pediatric infectious disease journal》1991,10(8):578-584
The role of Haemophilus influenzae in acute purulent conjunctivitis was studied during an outbreak among children in day care. Five day-care centers contributed 20 cases and 35 controls. All the children were subjected to culture of the nasopharynx and the eyes. H. influenzae was carried in the nasopharynx of 53% of the children (range between day care centers, 20 to 91%). Of the 20 children with acute conjunctivitis 8 had eye cultures positive for H. influenzae, 2 had Moraxella and the remaining were culture-negative. Ten colonies of H. influenzae were isolated from each positive culture and identified by capsular type, biotype and multi-locus enzyme electrophoresis. All but one of the isolates were nonencapsulated. They belonged to 4 biotypes and 8 electrophoretic types. The same strain was recovered from the eyes and nasopharynx of the symptomatic children, suggesting that the H. influenzae in the eyes originated from the nasopharynx. There was no evidence for spread of the same H. influenzae strains between day-care centers. Even within each center the Haemophilus strains recovered from the eyes varied among the symptomatic children. The in vitro capacity to attach to oropharyngeal epithelial cells was not increased among the H. influenzae recovered from the eyes. The results question if the majority of conjunctivitis cases were caused by H. influenzae and suggested that eyes were colonized with the nasopharyngeal carrier strain rather than infected by an isolate with special virulence for the eye. 相似文献
972.
J I Adinma 《International journal of fertility》1991,36(3):153-156
A case of successful quadruplet pregnancy followed from date of diagnosis, through delivery, and to the third year of life is presented. The emotional, social, and economic problems encountered by the parents and hospital personnel are examined with a detailed analysis of the financial burden placed on all parties. Individual, voluntary donations made at the time of delivery have proved insufficient to cover the care involved before, during, and after the birth of multiples. A more concrete commitment on the part of government in the form of legislation or subvention is suggested in order to ease some of the stress on the parents of multiples. 相似文献
973.
The role of lymphokines was estimated in induction of autoreactive T-cells during Langat virus infection in mice. It was shown that in vitro cultured splenocytes from virus-infected animal containing autoreactive lymphocytes (ARL) spontaneously produce a lymphokine which is capable to activate the autoreactivity of lymphocytes derived from the spleen of intact syngeneic mice. The capacity of this lymphokine to activate the autoreactivity of acceptor cells within 2 hr was demonstrated by local graft-versus host reaction (GVHR) in the donor-recipient system. According to their surface markers (theta-antigen expression, absence of immunoglobulins) the lymphokine activating autoreactivity (LAA) producers may belong to T-lymphocyte population. Autoreactivity could be induced by the lymphokine only if the LAA producers and acceptors were compatible by the major histocompatibility complex antigens. 相似文献
974.
975.
Piotr Kozlowski Alastair M. Buchan Ursula I. Tuor Dong Xue Zhi-Gao Huang Karen E. Chaundy John K. Saunders 《Magnetic resonance in medicine》1997,37(3):346-354
31P, 1H and lactate spectroscopic imaging was used to evaluate the effects of hypothermia on focal cerebral ischemia produced by middle cerebral artery occlusion. The effects on high energy phosphate metabolism, pH, lactate and NAA were investigated in 24 spontaneously hypertensive rats subjected to either permanent or transient ischemia. Under either normothermic (37.5°C) or hypothermic (32°C) conditions, with permanent 6-h occlusion, there was little difference between groups in either the NMR measurements or the volume of infarction. In animals that underwent 3 h of ischemia followed by 12 h of reperfusion, the ischemic changes in lactate, pH, NAA, and high-energy phosphate returned toward control values, and there was a protective effect of hypothermia (infarct volume of 211 ± 26 and 40 ± 14 mm3 in normothermic and hypothermic groups, respectively). Thus, hypothermia did not ameliorate the changes in lactate, pH, NAA, or high energy phosphate levels occurring during ischemia, however, during reperfusion there was an improvement in both the recovery of these metabolites and pathological outcome in hypothermic compared with normothermic animals. 相似文献
976.
Measurement of γ-enolase release, a new method for selective quantification of neurotoxicity independently from glial lysis 总被引:4,自引:0,他引:4
We have developed a sensitive enzymatic-immunoassay to quantify the level of gamma-enolase (a specific neuronal enzyme) which is released from cultured cells after exposure to various toxins. We show that this method can estimate selectively neuronal cell death without significantly interfering with glial cell death. Indeed, no gamma-enolase is released when glial cells are killed with free-radical producing agents. Experiments comparing the levels of neuronal cell death induced by NMDA or free-radical producing drugs, performed either by measuring gamma-enolase release or using the classical fluorescein diacetate method, yielded similar results. In addition to selectively follow neuronal death in a mixed population of neurons and glial cells, this method provides a way of determining the cell death kinetics from a single culture dish, since enolase can be measured on small samples taken from the culture medium. Finally, we propose these two methods as being complementary and useful neuronal and other cellular death indexes and also to understand the complex problem of glial influence on neuronal survival or death. 相似文献
977.
978.
979.
980.
T L Iashina M O Favorov I V Shakhgil'dian S N Firsova A E Eraliev L D Zhukova R G Reznichenko 《Voprosy virusologii》1992,37(4):194-196
From two regions differing by the levels of incidence of hepatitis B, 2019 blood serum specimens from normal population were examined for markers of HBV infection. In Moscow, among 1040 samples examined HBsAg was found in 2.0%, anti-HBs in 10.0%, anti-HBc in the absence of HBsAg and anti-HBs in 4.5%. In the Osh Province of Kirgizstan, among 979 subjects examined the same markers were found in 10.3%, 22.4%, and 14.0%, respectively. In this area, HBsAg was detected most frequently among infants (14.9% in infants under 1 year), in whom HBs-antigenemia was combined with the presence of HBeAg in 54.5% and with anti-HBc-IgM in 69.2%. Antibody to delta antigen (anti-delta) was found in 24 (25.8%) out of 93 HBsAg-positive subjects in the Osh Province but in none of 21 subjects with HBs-antigenemia in Moscow. 相似文献