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51.
Gastroduodenoscopy and retrograde cholangiopancreatography has been performed on 25 occasions in 20 children aged between 7 and 16. Radiographs of the clinically relevant duct or ducts were achieved in 96% of attempts, with no complications. The diagnostic information proved useful clinically; in particular it provided a precise map if biliary or pancreatic surgery was being contemplated. Several unexpected congenital duct anomalies were found. This and other recent reports, particularly from Germany, indicate that endoscopic retrograde cholangiopancreatography deserves greater application in children, and can also be used in babies. 相似文献
52.
The risk of Pneumocystis carinii pneumonia among men infected with human immunodeficiency virus type 1. Multicenter AIDS Cohort Study Group 总被引:23,自引:0,他引:23
J Phair A Mu?oz R Detels R Kaslow C Rinaldo A Saah 《The New England journal of medicine》1990,322(3):161-165
We assessed the risk of pneumonia due to Pneumocystis carinii in 1665 participants in the Multicenter AIDS Cohort Study who were seropositive for human immunodeficiency virus type 1 (HIV-1) but did not have the acquired immunodeficiency syndrome (AIDS) and were not receiving prophylaxis against P. carinii. During 48 months of follow-up, 168 participants (10.1 percent) had a first episode of P. carinii pneumonia. The risk was greatly increased in participants with CD4+ cell counts at base line of 200 per cubic millimeter or less (relative risk, 4.9; 95 percent confidence interval, 3.1 to 8.0). Although most participants (60.7 percent) described no HIV-1-related symptoms at the clinic visit at which a CD4+ cell count of 200 per cubic millimeter or less was first noted, this finding during follow-up was also associated with an increased risk of P. carinii pneumonia. The development of thrush or fever significantly and independently increased the risk of P. carinii pneumonia in these patients (adjusted relative risks, 1.86 and 2.15 for thrush and fever, respectively). Most participants with CD4+ cell counts above 200 per cubic millimeter who had P. carinii pneumonia within six months were symptomatic. We conclude that P. carinii pneumonia is unlikely to develop in HIV-1-infected patients unless their CD4+ cells are depleted to 200 per cubic millimeter or below or the patients are symptomatic, and therefore that prophylaxis should be reserved for such patients. 相似文献
53.
Rokey R; Verani MS; Bolli R; Kuo LC; Ford JJ; Wendt RE; Schneiders NJ; Bryan RN; Roberts R 《Radiology》1986,158(3):771-774
The feasibility of using magnetic resonance (MR) imaging to estimate myocardial infarct size was explored in an in vitro model using only the inherent differences in contrast between infarcted and noninfarcted myocardium. Eight dogs underwent coronary occlusion; their hearts were removed 6 hours later. Estimates of T2 for normal and infarcted myocardium were derived from MR images. Infarct size was quantified anatomically using triphenyltetrazolium-chloride (TTC) staining and compared with MR estimates. The T2 values derived from the images clearly discriminated between infarcted (126 +/- 22 msec) and normal myocardium (88 +/- 10 msec, P less than .05), providing images with good contrast between normal and infarcted myocardium. Comparable differences in T2 values were also noted from spectrometric determinations. Estimates of infarct size by MR imaging compared well with TTC estimates (r = 0.98) over a wide range of infarct sizes from 3% to 29% of the left ventricular mass. These results suggest the potential for in vivo quantification of infarct size based on the inherent contrast difference between infarcted and normal myocardium. 相似文献
54.
Carleigh B. Krubiner Ruth R. Faden Ruth A. Karron Margaret O. Little Anne D. Lyerly Jon S. Abramson Richard H. Beigi Alejandro R. Cravioto Anna P. Durbin Bruce G. Gellin Swati B. Gupta David C. Kaslow Sonali Kochhar Florencia Luna Carla Saenz Jeanne S. Sheffield Paulina O. Tindana 《Vaccine》2021,39(1):85-120
Zika virus, influenza, and Ebola have called attention to the ways in which infectious disease outbreaks can severely – and at times uniquely – affect the health interests of pregnant women and their offspring. These examples also highlight the critical need to proactively consider pregnant women and their offspring in vaccine research and response efforts to combat emerging and re-emerging infectious diseases. Historically, pregnant women and their offspring have been largely excluded from research agendas and investment strategies for vaccines against epidemic threats, which in turn can lead to exclusion from future vaccine campaigns amidst outbreaks. This state of affairs is profoundly unjust to pregnant women and their offspring, and deeply problematic from the standpoint of public health. To ensure that the needs of pregnant women and their offspring are fairly addressed, new approaches to public health preparedness, vaccine research and development, and vaccine delivery are required. This Guidance offers 22 concrete recommendations that provide a roadmap for the ethically responsible, socially just, and respectful inclusion of the interests of pregnant women in the development and deployment of vaccines against emerging pathogens. The Guidance was developed by the Pregnancy Research Ethics for Vaccines, Epidemics, and New Technologies (PREVENT) Working Group – a multidisciplinary, international team of 17 experts specializing in bioethics, maternal immunization, maternal-fetal medicine, obstetrics, pediatrics, philosophy, public health, and vaccine research and policy – in consultation with a variety of external experts and stakeholders. 相似文献
55.
Abstract: Polymorphisms in genes encoding transporters associated with antigen processing (TAP) have been associated with heterogeneity of disease progression in HTV-l-infected homosexual men. In our recent AIDS-related studies of cohorts from Rwanda and Zambia, four new polymorphic sites in the TAP2 coding region were detected by single-strand conformation polymorphism (SSCP) and confirmed by bi-directional nucleotide sequencing and restriction enzyme digestion. The first, a substitution of Thr (GCC) for Ala (ACC) at codon position 374 in exon 5, was found in about 13% of Rwandans and Zambians ( n =213). The remaining 3 new polymorphisms were seen in the 7th exon with changes of 458Thr-ACG to ACA, 466Gly-GGG to GGA, and 467Val-GTT to Ile-ATT, respectively. These 3 variants occurred exclusively on the same chromosome and appeared to have arisen together from the 374Thr-bearing allele. Analyses of the relationship between the 374Thr-457Ile segment and the nearby markers in DQB1 and DRB1 suggested the existence of a unique extended haplotype related to these newly identified variants. 相似文献
56.
57.
Hasegawa BH; Naimuddin S; Dobbins JT d; Mistretta CA; Peppler WW; Hangiandreou NJ; Cusma JT; McDermott JC; Kudva BV; Melbye KM 《Radiology》1986,159(2):537-543
The feasibility of producing patient-specific beam attenuators for chest radiography has been investigated using an anthropomorphic phantom and a human volunteer. A low-dose test exposure is digitized, processed, and used to print a small cerium filter, which is placed in the x-ray beam near the collimator. The final radiograph is recorded on film. The technique results in relatively uniform film exposure, so that structures in all regions of the chest are simultaneously displayed with optimal film contrast. The equalized exposure improves image quality in the normally underpenetrated regions and reduces the role of cross-scatter from the lungs. The image is analogous to optical or computer-processed unsharp masking techniques, but the processing is accomplished in the x-ray beam and results in an improved exposure distribution, giving advantages that cannot be achieved with image processing techniques alone. 相似文献
58.
Public Health Service study of Reye's syndrome and medications. Report of the main study 总被引:2,自引:0,他引:2
E S Hurwitz M J Barrett D Bregman W J Gunn P Pinsky L B Schonberger J S Drage R A Kaslow D B Burlington G V Quinnan 《JAMA》1987,257(14):1905-1911
Between January 1985 and May 1986, following completion of a pilot study, a main study concerning the possible association between Reye's syndrome and salicylates was conducted. Twenty-seven patients with stage II or deeper Reye's syndrome whose diagnoses were confirmed by an expert panel and who had appropriate antecedent illnesses (chickenpox, respiratory illness, or gastrointestinal illness) prior to the onset of Reye's syndrome were compared with 140 controls matched for age, race (black or not black), and type and timing of onset of antecedent illness. Controls were selected from the same hospital, emergency room, or school as case-patients or were identified by random-digit telephone dialing. As in the pilot study, a strong statistical association with ingestion of salicylates during the antecedent illness and prior to the onset of Reye's syndrome was observed (odds ratio, 40; lower 95% confidence limit, 5.8). Analysis of the independent risk of aspirin and nonaspirin salicylates revealed a significant association with aspirin (odds ratio, 26; lower 95% confidence limit, 6.4); the independent risk of nonaspirin salicylates could not be assessed because only two cases were not exposed to aspirin. Assessment of epidemiologic issues of concern, including case-control differences in the severity of the antecedent illness, did not explain the high odds ratios that were observed. The high percentage of patients with Reye's syndrome exposed to salicylates (greater than or equal to 90%) in this and prior studies suggests that, though the reported incidence of Reye's syndrome has declined in recent years, concomitant with a decline in salicylate use among children, a majority of Reye's syndrome cases may be attributable to salicylate use. 相似文献
59.
The epidemiology and natural history of infection with the human immunodeficiency virus (HIV) is reviewed. HIV is associated with a broad spectrum of disease, including AIDS. In presenting the natural history, early and late clinical manifestations, diagnosis of infection, incubation and latency periods, and survival time are discussed. Data from the published literature on the distribution of HIV infection in the adult U.S. population and factors that affect the acquisition and spread of the virus are also reviewed. Understanding of the epidemiology of this infection in certain high-risk groups is substantial and has provided a clear focus for preventive efforts and counseling. Many questions about spread in heterosexuals and about factors that may affect the natural history of the disease await completion of ongoing and planned studies. 相似文献
60.
TEELUCKSINGH S; STEER CR; THOMPSON CJ; SECKL JR; DOUGLAS NJ; EDWARDS CRW 《QJM : monthly journal of the Association of Physicians》1991,78(2):185-190
We describe a young man who developed extensive hypothalamicdysfunction including diabetes insipidus, adipsia, hyperprolactinaemia,and poikiliothermia together with central sleep apnoea followingexposure to toluene. 相似文献