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101.
OBJECTIVES/HYPOTHESIS: The objective was to determine whether post-tonsillectomy hemorrhages occur more frequently in redheaded children, in patterns of threes, on Friday-the-13th days, or with the full moon. STUDY DESIGN: Case-control analysis. METHODS: The authors performed multiple statistical analyses of all children undergoing tonsillectomy at Temple University Children's Medical Center (Philadelphia, PA) during a 29-month period. Children readmitted to the hospital with or without surgical control of bleeding were compared with children who did not bleed. Relation of post-tonsillectomy hemorrhages to the phase of the moon was evaluated using a standard normal deviate. The frequency of surgery performed on Friday-the-13th days was compared with a differently dated Friday chosen at random. Clusters of three hemorrhages in a 7-day period were recorded. Families of children were contacted and asked whether their child had red hair. A chi analysis compared redheaded and non-redheaded tonsillectomy patients. RESULTS: Twenty-eight of 589 tonsillectomy cases performed required readmission for bleeding events. Twenty tonsillectomies occurred on a full-moon day, resulting in one bleeding event. One cluster of three post-tonsillectomy hemorrhages occurred in a 7-day period. Four of the children who bled had red hair. Two tonsillectomies occurred on Friday the 13th, with no associated hemorrhage. Statistical analysis revealed a random pattern to post-tonsillectomy hemorrhage. CONCLUSION: Post-tonsillectomy hemorrhages do not occur in clusters of three and are not more frequent with the full moon or on Friday the 13th. The bleeding rate among children with red hair is similar to that of non-redheaded children. 相似文献
102.
Neuronal nitric oxide synthase and N-methyl-D-aspartate neurons in experimental carbon monoxide poisoning 总被引:3,自引:0,他引:3
Thom SR Fisher D Zhang J Bhopale VM Cameron B Buerk DG 《Toxicology and applied pharmacology》2004,194(3):280-295
We measured changes in nitric oxide (NO) concentration in the cerebral cortex during experimental carbon monoxide (CO) poisoning and assessed the role for N-methyl-d-aspartate receptors (NMDARs), a glutamate receptor subtype, with progression of CO-mediated oxidative stress. Using microelectrodes, NO concentration was found to nearly double to 280 nM due to CO exposure, and elevations in cerebral blood flow, monitored as laser Doppler flow (LDF), were found to loosely correlate with NO concentration. Neuronal nitric oxide synthase (nNOS) activity was the cause of the NO elevation based on the effects of specific NOS inhibitors and observations in nNOS knockout mice. Activation of nNOS was inhibited by the NMDARs inhibitor, MK 801, and by the calcium channel blocker, nimodipine, thus demonstrating a link to excitatory amino acids. Cortical cyclic GMP concentration was increased due to CO poisoning and shown to be related to NO, versus CO, mediated guanylate cyclase activation. Elevations of NO were inhibited when rats were infused with superoxide dismutase and in rats depleted of platelets or neutrophils. When injected with MK 801 or 7-nitroindazole, a selective nNOS inhibitor, rats did not exhibit CO-mediated nitrotyrosine formation, myeloperoxidase (MPO) elevation (indicative of neutrophil sequestration), or impaired learning. Similarly, whereas CO-poisoned wild-type mice exhibited elevations in nitrotyrosine and myeloperoxidase, these changes did not occur in nNOS knockout mice. We conclude that CO exposure initiates perivascular processes including oxidative stress that triggers activation of NMDA neuronal nNOS, and these events are necessary for the progression of CO-mediated neuropathology. 相似文献
103.
104.
Tripodi A Bressi C Carpenedo M Chantarangkul V Clerici M Mannucci PM 《Thrombosis research》2004,113(1):35-40
Whole blood coagulation monitors are increasingly used for patient self-testing to control oral anticoagulation, but there are no comprehensive quality assurance (QA) programs to check their performance. We report on the experience with one of such programs applied in a field study where patients on prothrombin time (PT)-international normalized ratio (INR) self-testing were asked to bring their monitors to the anticoagulation clinic for checking.PT-INR testing was performed three times over 3 months with 14 patient's monitors and test strips on three recalcified QA plasmas by an experienced laboratory operator. Each patient was also asked to perform PT-INR self-testing (his/her own capillary blood) which was then compared to the laboratory PT-INR (plasma).Overall, the comparison between the observed and the consensus PT-INR on QA plasmas was acceptable with the majority of measurements lying within ±15% or 20% of the consensus values. The comparison between the PT-INR self-testing and the laboratory method was also acceptable: overall, there was no statistical significant difference between the mean PT-INR values and the majority of paired measurements were less than 15% or 20% apart.In conclusion, our results show that the proposed QA scheme is feasible and may be implemented on a larger scale. Monitors should be recalled periodically to the clinic where they have been prescribed to the patient. During each visit, the clinic may check the monitors and patient self-testing performance as described. Such comprehensive QA system would make monitoring of oral anticoagulant treatment by self-testing safer and more effective. 相似文献
105.
Das M Kumari V Soni W Ettinger U Binneman B Hughes C Mehrotra R Sharma T 《Schizophrenia bulletin》2004,30(2):241-253
Neurological soft signs (NSS) are nonspecific indicators of brain dysfunction that are found to be in excess and correlated with cognitive dysfunction and psychopathology in patients with schizophrenia. The aim of the study was to examine whether the severity of NSS determines the efficacy of atypical antipsychotics in schizophrenia. Forty-three patients with schizophrenia were assessed on psychopathology and cognitive domains of executive functioning, memory, attention, and psychomotor speed at baseline and 6 months after they had been switched from typical to atypical antipsychotics. NSS were examined at baseline. The high-NSS group showed more severe psychopathology and greater impaired cognitive function than the low-NSS group at baseline. Following treatment, there were improvements in cognitive functioning and psychopathology with the low-NSS group, which showed significant improvements on measures of verbal fluency, memory, and psychomotor speed and negative symptoms. The high-NSS group also showed improvements on most of these measures, but the improvement was less than that seen in the low-NSS group. The presence of high NSS in schizophrenia patients impedes the improvement in cognitive function with atypical antipsychotics treatment. 相似文献
106.
Recent years have seen a dramatic growth in the number of studies using prepulse inhibition (PPI) paradigms to index information processing deficits in schizophrenia. There are, however, robust sex differences in PPI in healthy subjects, with women exhibiting less PPI than men in the absence of any psychopathology. To investigate the role of sex in prepulse modification deficits in the long-term course of schizophrenia, we assessed PPI (response inhibition with the prepulse preceding the pulse by 30-150 ms) and prepulse facilitation (PPF; response facilitation with the prepulse preceding the pulse by 1000 ms) of the acoustic startle response in 42 chronic schizophrenia patients (27 men; all 42 on typical antipsychotics) and 35 controls (15 men). The results revealed that healthy women showed less PPI than healthy men. Men with schizophrenia showed less PPI compared to healthy men, but women with schizophrenia did not differ in PPI from healthy women. Age of illness onset negatively correlated to PPI in male patients. There was no significant effect of sex in PPF, and although patients (regardless of sex) showed less PPF relative to controls, this effect was abolished when the current age was co-varied for. These findings indicate sex differences in PPI deficits in schizophrenia. Future studies of schizophrenia patients need to take sex and age of subjects into account to optimise the investigation of PPI deficits, and their clinical, neural, and pharmacological correlates. 相似文献
107.
108.
Gandhi NM Maurya DK Salvi V Kapoor S Mukherjee T Nair CK 《Journal of radiation research》2004,45(3):461-468
Gamma-radiation induced strand breaks in plasmid pBR322 DNA. Glycyrrhizic acid (GZA) protected plasmid DNA from radiation-induced strand breaks, as the disappearance of super-coiled (ccc) form was prevented by the compound with a dose-reduction factor of 2.04 at 2.5 mM concentration. Studies of comet assay on human peripheral blood leukocytes exposed to gamma radiation in the presence and absence of glycyrrhizic acid ex vivo revealed that this compound protected the cellular DNA from radiation-induced strand breaks in a concentration-dependent manner. An intraperitoneal administration of the GZA to mice one hour before exposure to gamma radiation protected cellular DNA from radiation-induced strand breaks in peripheral blood leucocytes and bone marrow cells, as revealed by comet assay. Pulse radiolysis studies indicated that glycyrrhizic acid offered radioprotection by scavenging free radicals. The rate constants for the reaction of glycyrrhizic acid with OH* and e(aq)- are 1.2 x 10(10 ) M(-1) s(-1) and 3.9 x 10(9 ) M(-1) s(-1), respectively. 相似文献
109.
This cross-sectional study was conducted to estimate the mean blood lead levels (BLL) and prevalence of lead toxicity in a representative sample of schoolchildren and children residing in an urban slum. In addition, the association of potential environmental risk factors with elevated BLL was studied. Children aged 4-6 years were selected from schools of the South zone of Delhi (n = 125) and from an urban slum (n = 65). Risk factors were recorded using a pre-tested questionnaire and blood lead and zinc protoporphyrin (ZPP) levels were estimated. The mean BLL was 7.8 microg/dl (SD 3.9) and the proportion of children with blood lead > or = 10 microg/dl was 18.4 per cent. Distance of the residence or school from a main road appeared to be associated with higher blood lead concentrations, but these differences were not statistically significant. In our setting, vehicular pollution may be a major contributing factor in lead contamination of the environment. 相似文献
110.
Pernicious anemia (PA) is an autoimmune disorder associated with atrophic gastritis, presence of antibodies to gastric parietal cells and intrinsic factor (IF) and vitamin B2 malabsorption leading to megaloblastic anemia. It has a comparatively higher prevalence in people of North European origin, is uncommon in Arabs and usually affects the elderly. This report, the first from Bahrain, describes a rare case of PA in young female. The presenting symptoms, clinical and laboratory features were similar to those described in classical elderly Caucasian patients. No association with any other autoimmune disease was detected. 相似文献