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991.
PURPOSE/METHOD: To point out that acanthamoeba keratitis can show therapeutical resistance to dibrome propamidine isethionate (Brolene). We have a late diagnosis case of corneal melting on a bilateral acanthamoeba keratitis. RESULTS/CONCLUSION: We performed corneal graft in one eye and found histopathological evidence of acanthamoeba. There was relapse in the graft in spite of Brolene treatment and good results when we changed to polyhidroxy methylbigunide (PHMB). In case of therapeutical Brolene resistance, PHMB can be an adequate alternative (Arch Soc Esp Oftalmol 2002; 77: 279-282).  相似文献   
992.
CASE REPORT: We present a case of congenital Horner's Syndrome in a four year-old boy. The patient was referred from the Dermatology ward after a check up for malformations present from birth on the left upper limb. A significant factor was determined: a varicella related infection in the mother during the 12th week of pregnancy. Blood tests confirmed a diagnosis of congenital varicella syndrome. DISCUSSION: Congenital Horner's Syndrome is a rare entity, caused mainly by traumatic deliveries. Very rarely it is produced by severe lesions, such as neuroblastoma or viral infections as varicella. In our case, condition was associated to ipsilateral malformations of the upper limb, which is typical from congenital varicella syndrome apparently due to radiculopathy produced by the virus.  相似文献   
993.
994.
OBJECTIVE: The lowest dose of aspirin shown to be effective in the secondary prevention of thrombotic accidents is 75 mg/day. Presystemic acetylation of cyclooxygenase and the formation of salicylic acid in the liver are fundamental to ensure optimum antithrombotic effects of aspirin. This study was designed to compare the effects of two forms of extended-release aspirin (at 75 mg/day) on prostanoid and nitric oxide synthesis in healthy volunteers. METHODS: The participants in this single-blind cross-over study (n = 6) were randomly assigned to receive one of three different formulations: plain-formulated aspirin (PF), extended-release aspirin that released acetylsalicylic acid steadily over 5 h (EX5) or an extended-release formulation that released 49% of the drug during the first 2 h after intake (EX2) and the rest of the dose during the subsequent 5 h. Laboratory analyses were done for platelet aggregation and thromboxane B2 (in whole blood), 6-keto-prostaglandin F1alpha (in leucocytes), neutrophil nitric oxide production and plasma nitrite/ nitrate levels. RESULTS: The PF and EX2 formulations inhibited platelet aggregation by 97% with no significant difference in effect between the two. In contrast, maximum inhibition of aggregation by the EX5 formulation was only 30%. Similar effects were found for platelet thromboxane production: PF and EX2 led to 99% inhibition, whereas EX5 led to 76% inhibition (P < 0.05). The inhibition of prostacyclin production differed in all three treatments (63% for PF, 40% for EX2 and 24% for EX5). The increase in leucocyte nitric oxide production also differed in all three treatments (1.01-fold the basal value with PF, 1.4-fold with EX5 and 3.6-fold with EX2). Both extended-release formulations maintained high levels of nitric oxide production 24 h after the last dose, whereas in the PF period nitric oxide concentration had returned to basal values after this time. The changes in plasma nitrite concentrations in each period of treatment were similar to those seen for leucocyte nitric oxide. CONCLUSION: The pharmacodynamic profile of the extended-release formulations was better than that of plain-formulated aspirin in terms of thromboxane/prostacyclin balance and nitric oxide production. However, the EX2 formulation inhibited platelet function more effectively than did the EX5 formulation.  相似文献   
995.
996.
We analyzed laboratory data from 1972 to 1997 from Santa Cruz, Bolivia, to determine risk factors for laboratory canine samples' testing positive for Rabies virus (RABV). Of 9,803 samples, 50.7% tested positive for RABV; the number of cases and the percentage positive has dropped significantly since 1978. A 5- to 6-year cycle in rabies incidence was clearly apparent, though no seasonality was noted. Male dogs had significantly increased odds of testing positive for RABV (odds ratio [OR]=1.14), as did 1- to 2-year-old dogs (OR=1.73); younger and older dogs were at lower risk. Samples submitted from the poorer suburbs of the city were more likely to test positive for RABV (OR=1.71). Knowledge of the distribution of endemic canine rabies in an urban area will help focus control measures in a resource-poor environment.  相似文献   
997.
The approach which had been being employed to date for dealing with and classifying those aspects related to health and disability have been revised and updated thanks to the World Health Organization (WHO) having drafted the International Classification of Functioning, Disability and Health, which has now been accepted 191 countries after revamping the prior model and reaching a consensus regarding a new international model for describing and measuring health and disability. As background information, it must be recalled that the Classification of Impairments, Disabilities and Handicaps (CIDH) previously in effect was first published by the WHO in 1980. The process of revising this classification has resulted in some changes of far-reaching importance. The change in the name has been aimed at reflecting the wish to replace the negative perspective of impairments, disabilities and handicaps for a more neutral view of structure and function, considering the positive perspectives of activities and of participation. Another new aspect has been that of including a section related to environmental factors in recognition of their importance, given that by interacting with the health condition they may give rise to a disability, or, at the opposite end of the scale, may restore functioning. The data available has enabled the WHO make estimates including that of some 500 million years of life being lost annually due to disabilities related to health problems, which totals over one half of the years lost annually due to premature deaths. The main objective of this new classification is that of providing the conceptual framework by means of unified, standardized language with a view to of the underlying challenges, setting out a valuable instrument of practical use in public health.  相似文献   
998.
Throughout the 1990-2000 period, disasters (catastrophes) caused an average of 75,000 deaths yearly, injuring an average of 256 million people a year and causing economic losses totaling more than 650 billion euros. The magnitude of this problem, its impact on public health and on the degree of development of the populations involved are of such major importance as to warrant special interest from the public health standpoint, especially as a result of what are known as complex emergencies. The objective of this study is that of reviewing the definitions, the main concepts and the basic characteristics of disaster epidemiology. An analysis is also made of the risk factors involved in disasters, the impacts on public health of the main types of disasters and the main preventive strategies in terms of the different stages of the disaster cycle.  相似文献   
999.
Cyclooxygenase-2 is involved in the inflammatory component of the ischemic cascade, playing an important role in the delayed progression of the brain damage. The present study evaluated the pharmacological effects of the selective cyclooxygenase-2 inhibitor nimesulide on delayed neuronal death of hippocampal CA1 neurons following transient global cerebral ischemia in gerbils. Administration of therapeutically relevant doses of nimesulide (3, 6 and 12 mg/kg; i.p.) 30 min before ischemia and at 6, 12, 24, 48 and 72 h after ischemia significantly (P<0.01) reduced hippocampal neuronal damage. Treatment with a single dose of nimesulide given 30 min before ischemia also resulted in a significant increase in the number of healthy neurons in the hippocampal CA1 sector 7 days after ischemia. Of interest is the finding that nimesulide rescued CA1 pyramidal neurons from ischemic death even when treatment was delayed until 24 h after ischemia (34+/-9% protection). Neuroprotective effect of nimesulide is still evident 30 days after the ischemic episode, providing the first experimental evidence that cyclooxygenase-2 inhibitors confer a long-lasting neuroprotection. Oral administration of nimesulide was also able to significantly reduce brain damage, suggesting that protective effects are independent of the route of administration. The present study confirms the ability of cyclooxygenase-2 inhibitors to reduce brain damage induced by cerebral ischemia and indicates that nimesulide can provide protection when administered for up to 24 h post-ischemia.  相似文献   
1000.
In previous studies, we have shown that activation of protein kinase C (PKC) rapidly (within minutes) increases the activity and cell surface expression of the glutamate transporter EAAC1 in two systems that endogenously express this transporter (C6 glioma cells and cocultures of neurons and astrocytes). However, the magnitude of the increase in activity is greater than the increase in cell surface expression. In addition, certain compounds completely block the increase in cell surface expression but only partially attenuate the increase in activity. We hypothesized that PKC increases EAAC1 activity by increasing cell surface expression and catalytic efficiency and that two different subtypes of PKC mediate these effects. To address these hypotheses, the PKC subtypes expressed by C6 glioma cells were identified. Of the PKC subtypes that are activated by phorbol esters, only PKCalpha, PKCdelta, and PKCepsilon were observed. G?6976, a compound that blocks PKCalpha at concentrations that do not inhibit PKCdelta or PKCepsilon, partially inhibited the increase in uptake but completely abolished the increase in EAAC1 cell surface expression. The 'G?6976-insensitive' increase in activity was not associated with a change in total transporter expression but was associated with an increase in the V(max). Na(+)-dependent glycine transport was not increased, providing indirect evidence that the G?6976-insensitive increase in activity was not caused by a change in the Na(+) electrochemical gradient required for activity. Finally, by down-regulating different subtypes of PKC, we found evidence that PKCepsilon mediates the increase in EAAC1 activity that is independent of changes in cell surface expression and found further evidence that PKCalpha mediates the increase in cell surface expression. The potential relationship of the present work with a previously identified role for PKCalpha in certain forms of synaptic plasticity is discussed.  相似文献   
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