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31.
32.
目的 观察Intralipid对内毒素所致的多形核白细胞氧自由基产生的影响,方法 取22例健康志愿者静脉血,采用Boyum法提取多核白细胞(PMN)并在体外培养,采用不同剂量的脂多糖(LPS)刺激PMN,并和不同剂量Intralipid共同作用,采用NBT还原剂试验测定氧自由基的产生量。结果 LPS刺激各组的NBT值明显高于非刺激组,而且NBT值与LPS浓度明显相关,Intralipid可明显浓度 相似文献
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34.
Brenda Costall Robert J. Naylor Connie C. W. Tan 《Naunyn-Schmiedeberg's archives of pharmacology》1983,323(2):155-161
Summary Field stimulation of circular smooth muscle of guinea-pig stomach from the regions of the cardia and fundus caused contraction responses at low stimulation frequencies (0.25–1 Hz) with relaxation at higher frequencies (1–10 Hz), whilst tissues of the body and antrum responded with contraction throughout the frequency range. Atropine (10–9–10–8 M) antagonised the contraction responses of all tissues, with relaxation developing at higher concentrations (except for antral tissue). In contrast, metoclopramide (10–8–10–6 M) caused modest (cardia, fundus) or marked (body, antrum) enhancement of contractions to field stimulation, whilst domperidone (10–8–10–7 M), haloperidol (10–8–10–6 M), prazosin, propranolol and methysergide (10–8–10–6 M) failed to modify the contraction responses. However, whilst yohimbine and guanethidine failed to modify the contractions of the cardia, fundus and body tissues, those of the antral preparations were antagonised by nanomolar concentrations of yohimbine and by guanethidine (10–6–5×10–5 M). To optimise the relaxation responses for study, atropine was included in the physiological solution. Relaxation to field stimulation of preparations from the body and cardia, but not the fundus, was antagonised by reserpine pretreatment (5 mg/kg i.p., 24h), addition of guanethidine (10–5–10–4 M), phentolamine, prazosin or propranolol (10–7–10–6 M) (the effects of prazosin and propranolol being additive). Higher concentrations of haloperidol and domperidone antagonised the relaxation responses of the body preparations only. Metoclopramide, yohimbine and methysergide (10–8–10–6 M) were ineffective. Thus, it is concluded that the contractile effects of the 4 stomach areas to field stimulation reflects a major cholinergic involvement, with an additional 2-adrenoceptor contractile component in antral tissue. Relaxation responses of cardia and body tissue involve 2- and -adrenoceptors plus a further, unidentified, non-adrenergic component; the latter represents the total relaxation response of the fundic preparation. 相似文献
35.
Neurodevelopmental disorders in males related to the gene causing Rett syndrome in females (MECP2). 总被引:2,自引:0,他引:2
Ute Moog Eric E J Smeets Kees E P van Roozendaal Sam Schoenmakers Jos Herbergs Anneke M J Schoonbrood-Lenssen Connie T R M Schrander-Stumpel 《European journal of paediatric neurology》2003,7(1):5-12
Mutations in the MECP2 (methyl-CpG-binding protein 2) gene are known to cause Rett syndrome, a well-known and clinically defined neurodevelopmental disorder. Rett syndrome occurs almost exclusively in females and for a long time was thought to be an X-linked dominant condition lethal in hemizygous males. Since the discovery of the MECP2 gene as the cause of Rett syndrome in 1999, MECP2 mutations have, however, also been reported in males. These males phenotypically have classical Rett syndrome when the mutation arises as somatic mosaicism or when they have an extra X chromosome. In all other cases, males with MECP2 mutations show diverse phenotypes different from classical Rett syndrome. The spectrum ranges from severe congenital encephalopathy, mental retardation with various neurological symptoms, occasionally in association with psychiatric illness, to mild mental retardation only. We present a 21-year-old male with severe mental retardation, spastic tetraplegia, dystonia, apraxia and neurogenic scoliosis. A history of early hypotonia evolving into severe spasticity, slowing of head growth, breathing irregularities and good visual interactive behaviour were highly suggestive of Rett syndrome. He has a de novo missense mutation in exon 3 of the MECP2 gene (P225L). The clinical spectrum and molecular findings in males with MECP2 mutations are reviewed. 相似文献
36.
Acierno R Kilpatrick DG Resnick H Saunders B De Arellano M Best C 《Journal of traumatic stress》2000,13(3):381-396
A national household probability sample of 4,023 adolescents aged 12 to 17 years was surveyed by telephone via structured clinical interview to determine the impact of familial substance use, sexual and physical assault, witnessed violence, depression and posttraumatic stress disorder (PTSD) on risk of smoking. Results indicated that familial substance use increased risk of smoking only for boys and sexual assault or depression increased risk of smoking only for girls. Age, Caucasian ethnicity, and experiencing physical assault or witnessing violence elevated risk of current cigarette use for both genders. By contrast, PTSD per se was not associated with increased risk of smoking, after the effects of other variables were controlled. 相似文献
37.
Judith McFarlane RN DrPH FAAN Barbara Parker RN PhD FAAN Karen Soeken PhD Connie Silva RN PhD Sally Reel RN PhD 《Journal of obstetric, gynecologic, and neonatal nursing : JOGNN / NAACOG》1998,27(1):64-69
Objective: To evaluate an intervention protocol, administered during pregnancy, for increasing safety-seeking behaviors of abused women.
Design: Prospective, ethnically stratified cohort analysis.
Setting: Public prenatal clinics.
Participants: Pregnant women reporting physical or sexual abuse in the year before or during the present pregnancy. One hundred thirty-two women met study criteria, received the intervention, and were followed for 1 year after the completion of the pregnancy.
Intervention: Three education, advocacy, and community referral sessions that included information on safety behaviors.
Main outcome Measure: Adoption of safety behaviors by abused women. Safety behaviors were measured before the intervention, twice during pregnancy, and at 2, 6, and 12 months after completion of the pregnancy.
Results: Repeated measures analysis of variance showed a significant increase in adoption of each safety behavior (p < .0001), with most behaviors showing a significant increase after the first intervention session.
Conclusions: Pregnant women who were abused and were offered an intervention protocol report a significant increase in safety behavior adoption during and after pregnancy. Abuse during pregnancy is common. Identification of abuse and immediate clinical intervention that includes information about safety behaviors can result in safety behavior adoption that may prevent future abuse and increase the safety and well-being of women and infants. 相似文献
Design: Prospective, ethnically stratified cohort analysis.
Setting: Public prenatal clinics.
Participants: Pregnant women reporting physical or sexual abuse in the year before or during the present pregnancy. One hundred thirty-two women met study criteria, received the intervention, and were followed for 1 year after the completion of the pregnancy.
Intervention: Three education, advocacy, and community referral sessions that included information on safety behaviors.
Main outcome Measure: Adoption of safety behaviors by abused women. Safety behaviors were measured before the intervention, twice during pregnancy, and at 2, 6, and 12 months after completion of the pregnancy.
Results: Repeated measures analysis of variance showed a significant increase in adoption of each safety behavior (p < .0001), with most behaviors showing a significant increase after the first intervention session.
Conclusions: Pregnant women who were abused and were offered an intervention protocol report a significant increase in safety behavior adoption during and after pregnancy. Abuse during pregnancy is common. Identification of abuse and immediate clinical intervention that includes information about safety behaviors can result in safety behavior adoption that may prevent future abuse and increase the safety and well-being of women and infants. 相似文献
38.
Jennifer A. Westwood Geoffrey M. Matthews Jake Shortt David Faulkner Hollie J. Pegram Connie P.M. Duong Marta Chesi P. Leif Bergsagel Leslie L. Sharp Richard D. Huhn Phillip K. Darcy Ricky W. Johnstone Michael H. Kershaw 《Leukemia research》2014
In order to stimulate antigen presentation and T cell activity against cancer, we treated three different tumor models in mice with the monoclonal antibodies anti-CD40 plus anti-CD137 (BiMab). In a subcutaneous transplantable MC38 colon cancer model, there was significant enhancement in the survival of mice following BiMab treatment. Anti-CD40 has shown considerable success against lymphoma in previous studies by other investigators, and we also showed in this study that, in a model of Eμ-Myc lymphoma, there was a statistically significant enhancement of survival of mice following BiMab treatment. Following the success of the BiMab treatment in the previous two models, we wished to determine if it would be successful in a mouse model of multiple myeloma. Firstly, we tested a transplantable model of disease in which multiple myeloma cells derived from Vk*MYC mice were injected intravenously. A minor proportion of anti-CD137 and BiMab treated mice experienced prolongation of life beyond 250 days. Then we tested the therapy in a spontaneously occurring multiple myeloma model, in Vk*MYC transgenic mice. The majority of mice treated survived longer than control mice, although statistical significance was not demonstrated. 相似文献
39.
R. Austin Hicklin Linda Eisenhart Nicole Richetelli Meredith D. Miller Peter Belcastro Ted M. Burkes Connie L. Parks Michael A. Smith JoAnn Buscaglia Eugene M. Peters Rebecca Schwartz Perlman Jocelyn V. Abonamah Brian A. Eckenrode 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(32)
Forensic handwriting examination involves the comparison of writing samples by forensic document examiners (FDEs) to determine whether or not they were written by the same person. Here we report the results of a large-scale study conducted to assess the accuracy and reliability of handwriting comparison conclusions. Eighty-six practicing FDEs each conducted up to 100 handwriting comparisons, resulting in 7,196 conclusions on 180 distinct comparison sets, using a five-level conclusion scale. Erroneous “written by” conclusions (false positives) were reached in 3.1% of the nonmated comparisons, while 1.1% of the mated comparisons yielded erroneous “not written by” conclusions (false negatives). False positive rates were markedly higher for nonmated samples written by twins (8.7%) compared to nontwins (2.5%). Notable associations between training and performance were observed: FDEs with less than 2 y of formal training generally had higher error rates, but they also had higher true positive and true negative rates because they tended to provide more definitive conclusions; FDEs with at least 2 y of formal training were less likely to make definitive conclusions, but those definitive conclusions they made were more likely to be correct (higher positive predictive and negative predictive values). We did not observe any association between writing style (cursive vs. printing) and rates of errors or incorrect conclusions. This report also provides details on the repeatability and reproducibility of conclusions, and reports how conclusions are affected by the quantity of writing and the similarity of content.Forensic science is under scrutiny, particularly for pattern-based disciplines in which source conclusions are reported. The National Research Council report Strengthening Forensic Science in the United States: A Path Forward (1) stated that “The scientific basis for handwriting comparisons needs to be strengthened” and noted that “there has been only limited research to quantify the reliability and replicability of the practices used by trained document examiners.” The President’s Council of Advisors on Science and Technology (PCAST) report Forensic Science in Criminal Courts: Ensuring Scientific Validity of Feature-Comparison Methods (2) expressed concerns regarding the validity and reliability of conclusions made by forensic examiners, and called for empirical testing: “The only way to establish the scientific validity and degree of reliability of a subjective forensic feature-comparison method—that is, one involving significant human judgment—is to test it empirically by seeing how often examiners actually get the right answer. Such an empirical test of a subjective forensic feature-comparison method is referred to as a ‘black-box test.’” The National Commission on Forensic Science also called for such testing (3). Although the accuracy and reliability of conclusions made by forensic document examiners (FDEs) have been the focus of multiple studies over the years (4–10), the designs of those studies are notably different from this study (and from PCAST’s recommendations), and therefore the resulting rates are not directly comparable (in particular, when comparing open-set to closed-set studies, comparing studies based on one-to-one vs. one-to-many examinations, and comparing studies that use notably different conclusion scales; see SI Appendix, Appendix B for a summary).This study was conducted to provide data that can be used to assess the scientific validity of handwriting comparisons, for use by policy makers, laboratory managers, the legal community, and FDEs. This study follows the approach used in the previous FBI Laboratory–Noblis latent print black box study (11) and later recommended by the PCAST report. The design utilizes open-set, one-to-one document comparisons to evaluate the conclusions reached by practicing FDEs when comparing writing samples selected to be broadly comparable to casework. The primary purposes of the study are to measure the accuracy of conclusions by FDEs when comparing handwriting samples and to assess reliability by measuring the reproducibility (interexaminer variability) and repeatability (intraexaminer variability) of those conclusions. Secondary purposes include reporting any associations between the accuracy of the decisions in this study, factors related to the participants (such as training or experience), and factors related to the samples (such as quantity of writing, comparability of content, limitations, or style of writing). 相似文献
40.
David M. Homa Linda J. Neff Brian A. King Ralph S. Caraballo Rebecca E. Bunnell Stephen D. Babb Bridgette E. Garrett Connie S. Sosnoff Lanqing Wang 《上海预防医学》2016,28(9):666-670
烟草燃烧产生的二手烟暴露会导致在婴儿和儿童中发生幼儿猝死综合征(sudden infant death syndrome,SIDS)、呼吸道感染、耳部炎症和哮喘发作等;在成人非吸烟者中会导致冠心病、中风和肺癌。 相似文献