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排序方式: 共有690条查询结果,搜索用时 0 毫秒
31.
Reduction of sound levels with antinoise in MR imaging 总被引:1,自引:0,他引:1
A combination of active and passive techniques was used to reduce the sound levels in magnetic resonance imagers. These techniques were integrated into an existing audio system. Measurements of sound reduction varied with the protocol being used and averaged 9.9 dB with coaxial cabling and 14.2 dB with fiberoptic conduction of the feedback signal to a controller. Patient comfort and communication were improved. 相似文献
32.
To report our clinical experience on the use of oral erythromycin for the treatment of severe gastrointestinal dysmotility in preterm infants.
A case series study of seven preterm infants (six were very low birthweight) with severe intestinal dysmotility in a tertiary neonatal centre.
All responded favourably without adverse effects and tolerated full enteral feeding within 1–2 weeks of the commencement of the drug.
As prolonged total parenteral nutrition carries significant risk of complications, this therapy could be considered in selected preterm infants who fail to establish enteral feeding after an extended period, and in whom an anatomically obstructive lesion of the gastrointestinal tract has been excluded. Meanwhile, we would caution against the widespread implementation of this therapeutic approach until formal evaluation by randomized controlled trials have established the exact role of erythromycin, or its analogues, in the treatment of intestinal dysmotility in preterm infants. 相似文献
Methodology:
A case series study of seven preterm infants (six were very low birthweight) with severe intestinal dysmotility in a tertiary neonatal centre.
Results:
All responded favourably without adverse effects and tolerated full enteral feeding within 1–2 weeks of the commencement of the drug.
Conclusions:
As prolonged total parenteral nutrition carries significant risk of complications, this therapy could be considered in selected preterm infants who fail to establish enteral feeding after an extended period, and in whom an anatomically obstructive lesion of the gastrointestinal tract has been excluded. Meanwhile, we would caution against the widespread implementation of this therapeutic approach until formal evaluation by randomized controlled trials have established the exact role of erythromycin, or its analogues, in the treatment of intestinal dysmotility in preterm infants. 相似文献
33.
OBJECTIVES: To investigate the relationship of specific nutrients and food items with oral precancerous lesions among tobacco users.
DESIGN: A population-based case-control study. SETTING: Villages in Palitana taluk of Bhavnagar district, Gujarat, India.
SUBJECTS AND METHODS: An interviewer-administered food frequency questionnaire, developed and validated for this population, was used to estimate nutrient intake in blinded, house-to-house interviews. Among 5018 male tobacco users, 318 were diagnosed as cases. An equal number of controls matched on age (±5 years), sex, village, and use of tobacco were selected.
MAIN OUTCOME MEASURES: Odds ratios (OR) from multiple logistic regression analysis controlling for relevant variables (type of tobacco use and economic status).
RESULTS: A protective effect of fibre was observed for both oral submucous fibrosis (OSF) and leukoplakia, with 10% reduction in risk per g day-1 ( P < 0.05). Ascorbic acid appeared to be protective against leukoplakia with the halving of risk in the two highest quartiles of intake (versus the lowest quartile: OR = 0.46 and 0.44, respectively; P < 0.10). A protective effect of tomato consumption was observed in leukoplakia and a suggestion of a protective effect of wheat in OSF.
CONCLUSION: In addition to tobacco use, intake of specific nutrients may have a role in the development of oral precancerous lesions. 相似文献
DESIGN: A population-based case-control study. SETTING: Villages in Palitana taluk of Bhavnagar district, Gujarat, India.
SUBJECTS AND METHODS: An interviewer-administered food frequency questionnaire, developed and validated for this population, was used to estimate nutrient intake in blinded, house-to-house interviews. Among 5018 male tobacco users, 318 were diagnosed as cases. An equal number of controls matched on age (±5 years), sex, village, and use of tobacco were selected.
MAIN OUTCOME MEASURES: Odds ratios (OR) from multiple logistic regression analysis controlling for relevant variables (type of tobacco use and economic status).
RESULTS: A protective effect of fibre was observed for both oral submucous fibrosis (OSF) and leukoplakia, with 10% reduction in risk per g day
CONCLUSION: In addition to tobacco use, intake of specific nutrients may have a role in the development of oral precancerous lesions. 相似文献
34.
PC Ng J Hiu TF Fok EAS Nelson KL Cheung W Wong 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(8):955-956
We report an unusual case of localized congenital tuberculosis otitis in a preterm infant. Unlike disseminated congenital cases, the manifestations of localized otitis are associated with a triad of signs: (i) regional lymphadenopathy in the absence of typical systemic features of tuberculosis; (ii) delayed onset of presentation; and (iii) refractory otitis unresponsive to conventional antimicrobial agents. The need for greater diligence in looking for neonatal tuberculosis is emphasized, especially in an ethnic or socioeconomic environment where the disease is prevalent. Congenital tuberculosis, otitis, preterm
PC Ng, Department of Paediatrics, Level 6, Clinical Sciences Building, Prince of Wales Hospital, Shatin, NT, Hong Kong 相似文献
PC Ng, Department of Paediatrics, Level 6, Clinical Sciences Building, Prince of Wales Hospital, Shatin, NT, Hong Kong 相似文献
35.
Vaslef SN Knudsen NW Neligan PJ Sebastian MW 《The Journal of trauma》2002,53(2):291-5; discussion 295-6
BACKGROUND: Massive transfusion of blood products in trauma patients can acutely deplete the blood bank. It was hypothesized that, despite a large allocation of resources to trauma patients receiving more than 50 units of blood products in the first 24 hours, outcome data would support the continued practice of massive transfusion. METHODS: A retrospective review of charts and registry data of trauma patients who received over 50 units of blood products in the first day was conducted for a 5-year period at a Level I trauma center. Patients were stratified into groups on the basis of the number of transfusions received. Results are expressed as mean +/- SD. Univariate analysis and multivariate logistic regression were used to identify those risk factors determined in the first 24 hours after admission that were predictive of mortality. Physiologic differences between survivors and nonsurvivors were also examined. RESULTS: Of 7,734 trauma patients admitted between July 1, 1995, and June 30, 2000, 44 (0.6%) received > 50 units of blood products in the first day. Overall mortality in these patients was 57%. There was no significant difference (p = 0.565, chi2) in mortality rate between patients who received > 75 units of blood products in the first day versus those who received 51 to 75 units. Multiple logistic regression analysis identified only one independent risk factor, base deficit > 12 mmol/L, associated with mortality. Base deficit > 12 mmol/L increases the risk of death by 5.5 times (p = 0.013; 95% confidence interval, 1.44-20.95). Neither the total blood product transfusion requirement in the first day nor the packed red blood cell transfusion amount in the first day were significant independent risk factors. Causes of the 25 deaths in this series included exsanguination in the operating room (n = 1) or in the surgical intensive care unit (n = 12), multiple organ failure/sepsis (n = 3), head injury (n = 3), respiratory failure (n = 2), cerebrovascular accident (n = 1), and other (n = 3). Of the survivors, 63% were discharged to home, 21% to rehabilitation, 11% to nursing home, and 5% to another acute care facility. Of the nonsurvivors, the mean Injury Severity Score was 43, 88% had a base deficit > 12 mmol/L, 68% had a Glasgow Coma Scale score < 8, and 64% had a Sequential Organ Failure Assessment score > 10. CONCLUSION: The 43% survival rate in trauma patients receiving > 50 units of blood products warrants continued aggressive transfusion therapy in the first 24 hours after admission. 相似文献
36.
Norton KI Kattan M Rao JS Cleveland R Trautwein L Mellins RB Berdon W Boechat MI Wood B Meziane M Platzker AC;P 《AJR. American journal of roentgenology》2001,176(6):1553-1558
OBJECTIVE: We prospectively studied children with and without maternally transmitted HIV-1 infection born to mothers infected with HIV-1 to determine the incidence of chronic radiographic lung changes (CRC) and to correlate these changes with clinical assessments. SUBJECTS AND METHODS: Between 1990 and 1997, we scored 3050 chest radiographs using a standardized form. Group I children (n = 201) were HIV-1-infected at enrollment. Group II children (n = 512) were enrolled prenatally or before 28 days postpartum and subsequently subdivided into group IIa (n = 86), children identified as HIV-1-infected; and group IIb (n = 426), those who were HIV-1-uninfected. CRC were defined as parenchymal consolidations or nodular disease lasting 3 months or more or increased bronchovascular markings or reticular densities lasting 6 months or more. Morbidity was assessed by CD4 counts, viral load, the presence of low oxygen saturation, wheezing, tachypnea, crackles, and clubbing. RESULTS: The cumulative incidence of chronic radiographic lung changes in HIV-1-infected children was 32.8% by 4 years old, with increased bronchovascular markings or reticular densities being most common. Chronic changes were associated with lower CD4 cell counts and higher viral loads. Resolution of these chronic changes was associated with decreasing CD4 cell counts but not with lower rates of clinical findings, viral load, or difference in survival. CONCLUSION: With increased survival, CRC are becoming more common. The resolution of these changes may indicate immunologic deterioration rather than clinical improvement. 相似文献
37.
Biomarkers for lysosomal storage disorders: identification and application as exemplified by chitotriosidase in Gaucher disease 总被引:1,自引:0,他引:1
Johannes M Aerts Marielle J van Breemen Anton P Bussink Karen Ghauharali Richard Sprenger Rolf G Boot Johanna E Groener Carla E Hollak Mario Maas Suzanne Smit Huub C Hoefsloot Age K Smilde Johannes PC Vissers Sheryas de Jong Dave Speijer Chris G de Koster 《Acta paediatrica (Oslo, Norway : 1992)》2008,97(S457):7-14
38.
Wang JF; Bashir M; Engelsberg BN; Witmer C; Rozmiarek H; Billings PC 《Carcinogenesis》1997,18(2):371-375
Chromium (Cr) is a human carcinogen and a potent DNA damaging agent.
Incubation of DNA with CrCl3 resulted in dose-dependent binding of Cr to
DNA and, at concentrations >20 microM, altered the electrophoretic
mobility of a 100 bp oligonucleotide. We also demonstrate that high
mobility group (HMG) proteins 1 and 2 bind Cr-damaged DNA (Cr-DNA). Protein
binding was lesion density-dependent, with maximal binding to DNA treated
with 100 microM CrCl3. HMG2 binds to Cr-DNA with a calculated Kd of
approximately 10(-9) M. These proteins also bound DNA obtained from
chromate-treated cells. These results suggest that the covalent attachment
of Cr to DNA induces alterations in DNA structure which are recognized by
HMG1 and HMG2. Therefore, these proteins may function as Cr-damaged DNA
recognition proteins in vivo and as a consequence of binding, may play a
role in directing the cellular response to Cr-DNA adduct formation.
相似文献
39.
NA Bridges JA Christopher PC Hindmarsh CG Brook 《Archives of disease in childhood》1994,70(2):116-118
The aetiology of 197 girls and 16 boys presenting with sexual precocity was reviewed. Ninety one girls and four boys had central precocious puberty (M:F 23:1); a cause was identified in all the boys but in only six girls. All boys with precocious puberty need detailed investigation; in girls investigation should be based on clinical findings, particularly the consonance of puberty. 相似文献
40.