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1.
Emma J. Walker Noni E. MacDonald Nehal Islam Nicole Le Saux Karina A. Top Deshayne B. Fell 《Vaccine》2019,37(13):1725-1735
Objective
To systematically review literature on uptake and timeliness of diphtheria-tetanus-pertussis, measles-mumps-rubella, and/or polio-containing vaccines in infants who were born preterm, with a low birth weight, and/or with chronic health conditions that were diagnosed within the first 6?months of life.Methods
Using a standardized search strategy developed by a medical librarian, records were extracted from MEDLINE, Embase, Database of Abstracts of Reviews of Effects, and CINAHL up to May 8, 2018.Results
Out of the 1997 records that were screened, we identified 21 studies that met inclusion criteria. Eleven studies assessed vaccine coverage and/or timeliness in preterm infants, 6 in low birth weight infants, and 7 in children with chronic health conditions. Estimates of coverage in these populations were highly variable, ranging from 40% to 100% across the vaccines and population groups.Conclusions
There is a lack of studies reporting coverage and timeliness of routine immunizations in special populations of children.Policy implications
Our review suggests a need for improved surveillance of immunization status in special populations of infants, as well as a need for standardization of reporting practices. 相似文献2.
3.
Spleen sizing by ultrasound in polycythaemia and thrombocythaemia: comparison with SPECT 总被引:3,自引:1,他引:2
M. Messinezy L. M. MacDonald T. O. Nunan N. B. Westwood S. Chinn & T. C. Pearson 《British journal of haematology》1997,98(1):103-107
Detection of non-palpable early splenic enlargement may aid diagnosis of primary polycythaemia (PP) and primary thrombocythaemia (PT). In this study linear spleen sizing by ultrasound has been compared with spleen volume estimation by single photon emission computerized tomography (SPECT) in 26 patients. Spleen length by ultrasound correlated well with SPECT volume estimation.
Ultrasound spleen length was also measured in 60 normal control subjects where the upper limit of the 95% reference range was 11.6 cm. Changes in spleen length with both age and body weight were substantial and overshadowed the imperfect reproducibility of this method. Therefore, interpretation of an individual's measured spleen length should be in relation to that predicted for adults of the same age and weight, particularly at the extremes of the younger, heavier patients and also the older, lighter patients.
Ultrasound spleen lengths of different patient groups (21 PP, 26 PT, 17 idiopathic erythrocytosis, 12 secondary polycythaemia, nine apparent polycythaemia) were compared both using the measured overall reference range and the differences from the values predicted for their age and weight. The comparison showed that almost all patients with PP whose spleens were not palpable had spleen lengths greater than the upper limit for the normal control group, but separation from the other patient groups was incomplete.
Detection of non-palpable splenomegaly by ultrasound length should remain a 'minor' criterion amongst the 'proposed modified diagnostic criteria' of PP. 相似文献
Ultrasound spleen length was also measured in 60 normal control subjects where the upper limit of the 95% reference range was 11.6 cm. Changes in spleen length with both age and body weight were substantial and overshadowed the imperfect reproducibility of this method. Therefore, interpretation of an individual's measured spleen length should be in relation to that predicted for adults of the same age and weight, particularly at the extremes of the younger, heavier patients and also the older, lighter patients.
Ultrasound spleen lengths of different patient groups (21 PP, 26 PT, 17 idiopathic erythrocytosis, 12 secondary polycythaemia, nine apparent polycythaemia) were compared both using the measured overall reference range and the differences from the values predicted for their age and weight. The comparison showed that almost all patients with PP whose spleens were not palpable had spleen lengths greater than the upper limit for the normal control group, but separation from the other patient groups was incomplete.
Detection of non-palpable splenomegaly by ultrasound length should remain a 'minor' criterion amongst the 'proposed modified diagnostic criteria' of PP. 相似文献
4.
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6.
Margaret MacDonald Matthew Law John Kaldor Jim Hales Gregory J. Dore 《The International journal on drug policy》2003,14(5-6):353
Objective: To examine the effectiveness of needle and syringe programmes (NSPs) in preventing HIV transmission among injecting drug users (IDUs).Methods: An ecological study design was used to determine change in HIV prevalence among injecting drug users between cities with and without NSPs. Several data sources, such as electronic journal databases, surveillance reports, websites, and index review of relevant journals, were used to identify studies of HIV seroprevalence among IDUs, and presence of NSPs. The rate of change in HIV prevalence was estimated by regression analysis.Results: There were 778 years of data from 99 cities globally included in the analysis. HIV prevalence decreased by 18.6% per annum in cities that introduce NSPs, and increased by 8.1% in cities that had never introduced NSPs (mean difference −24.7% [95% CI: −43.8, 0.5%], P=0.06). The mean difference was –33% when comparison was weighted to one over the variance of the regression estimator (29% decrease in cities with NSPs and 5% increase in cities without NSPs, P<0.001). When analysis was restricted to cities with first HIV seroprevalence less than 10%, the average annual change in seroprevalence was 18% lower in cities with NSPs (P=0.03).Conclusions: Despite the inherent limitations within an ecological study design, the study provides additional evidence that NSPs reduce transmission of HIV infection. The rapid spread of HIV among IDU populations and increasing rates of injecting in many countries calls for scaling up of NSPs as well as other harm reduction strategies. 相似文献
7.
8.
This paper explores the ways in which pre-teenage children try to avoid coming into contact with illegal drugs and then examines the factors and circumstances that facilitate or impede their efforts to achieve this. Their main strategy of avoiding certain groups or individuals was complicated by the fluid nature of young people's social groups and the unpredictable nature of their activities. Children who lived in areas in which illegal drugs were prevalent found it especially difficult to avoid coming into contact with them. While it was relatively easy for a child to avoid making friends with someone who was using drugs, the situation in which an existing friend started to use illegal drugs was much more difficult to deal with. The paper concludes that, while children should be encouraged to avoid certain groups and situations as their first line of defence, the problematic nature of this activity means that it is also essential that they continue to be provided with the skills necessary to deal effectively with situations in which illegal drugs are available. 相似文献
9.
De Leo V; Morgante G; Lanzetta D; D'Antona D; Bertieri RS 《Human reproduction (Oxford, England)》1997,12(2):357-360
We report the results of administration of danazol after suspension of
gonadotrophin-releasing hormone analogue (GnRHa) therapy for uterine
myomas. A total of 21 women with uterine myomas was treated with 100 mg
danazol for 6 months after GnRHa therapy. Uterine volume and endocrine
status were monitored monthly by ultrasound and assay of plasma
gonadotrophins, oestradiol and progesterone. The results show a rebound of
uterine volume about 30% less than in controls at the end of danazol
therapy. Menstrual cyclicity returned after 65 +/- 3 days in 16 subjects
and five patients remained amenorrhoeic. Hormone assays confirmed renewed
ovarian function in the women whose menstrual periods returned. Bone
mineral content was substantially reduced during GnRHa treatment but
improved significantly during danazol therapy even in the women who
remained amenorrhoeic. These results show the utility of danazol in
prolonging the therapeutic effects of GnRHa. The mechanism by which danazol
inhibits rebound of uterine volume may be due to its antiprogesterone
effects on uterine myomas.
相似文献
10.
The pharmacokinetics of gamma-glutamyl-L-dopa in normal and anephric rats and rats with glycerol-induced acute renal failure. 总被引:2,自引:2,他引:0 下载免费PDF全文
Y. A. Boateng H. E. Barber T. M. MacDonald J. C. Petrie M. R. Lee P. H. Whiting 《British journal of pharmacology》1990,101(2):301-306
1. The pharmacokinetics of gamma-glutamyl-L-dopa (gludopa) and its metabolite, L-dopa, have been studied in normal rats at three dose levels of gludopa: 2 mg kg-1, 5 mg kg-1 and 7.5 mg kg-1. The extent of metabolism in normal rats, and the pharmacokinetics in anephric rats and rats with glycerol-induced acute renal failure (ARF) were also studied at a gludopa dose of 2 mg kg-1. 2. Gludopa was extensively metabolised to L-dopa with only about 10% of an injected dose being excreted unchanged. Normal rats had a rapid gludopa clearance of 50.9 +/- 9.6 ml min-1 kg-1 and elimination rate constant of 2.99 +/- 0.27 h-1. The mean residence time and half-life were 20.9 +/- 1.4 and 14.4 +/- 1.0 min, respectively. The apparent volume of distribution at steady state was 1.05 +/- 0.18 l kg-1. 3. No statistically significant differences were found in the main pharmacokinetic parameters between ARF and controls for either gludopa or its metabolite L-dopa. 4. In anephric rats and controls the kidneys were found to contribute about 68.5% and 67.2% to the elimination of gludopa and the metabolite L-dopa, respectively. 5. These results confirm that gludopa is an efficient pro-drug for L-dopa, and that the kidneys are the major site of gludopa metabolism. It seems likely that the renal specificity of gludopa persists in ARF. 相似文献