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11.
Carriage of Haemophilus influenzae and Streptococcus pneumoniae in healthy Chinese and Vietnamese children in Hong Kong 总被引:1,自引:0,他引:1
RYT Sung JM Ling SM Fung SJ Oppenheimer DW Crook JTF Lau AFB Cheng 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(11):1262-1267
Nasopharyngeal carriage of Haemophilus influenzae and Streptococcus pneumoniae was studied in 621 healthy Chinese children and 300 healthy Vietnamese children aged from 2 months to 5 years in Hong Kong. The carriage rate of H, influenzae type b in Vietnamese children was 1.3% (CI 0.04-2.63%); it was zero in Chinese. The carriage rate of non-typable H. influenzae was 5.8% (CI 1.4-7.6%) in Chinese and 65.4% (CI 58.9-69.8%) in Vietnamese. The carriage rates of S. pneumoniae were 10.8% (CI 8.3-13.2%) and 55.7% (CI 50.1-61.3%) in Chinese and Vietnamese children, respectively. Univariate and multivariate logistic regression analyses were performed to search for factors associated with differences in carriage rates of both H. influenzae and S. pneumoniae between Chinese and Vietnamese children. Although older age, smaller living area and parental smoking were associated with higher carriage rates, these could not explain the remarkably low carriage rates of both bacteria in Chinese children. 相似文献
12.
Porter DW; Yakushiji H; Nakabeppu Y; Sekiguchi M; Fivash MJ Jr; Kasprzak KS 《Carcinogenesis》1997,18(9):1785-1791
The toxicity of Ni(II), Co(II) and Cu(II) in animals, and that of Cd(II) in
cultured cells, has been associated with generation of the promutagenic
lesion 8-oxo-7,8-dihydroguanine (8-oxoguanine) in DNA, among other effects.
One possible source of this base may be 8-oxo-7,8-
dihydro-2'-deoxyguanosine-5'-triphosphate (8-oxo-dGTP), a product of
oxidative damage to the nucleotide pool, from which it is incorporated into
DNA. To promote such incorporation, the metals would have to inhibit
specific cellular 8-oxo-dGTPases that eliminate 8-oxo-dGTP from the
nucleotide pool. The present study was designed to test such inhibition in
vitro on 8-oxo-dGTPases from two different species, the human MTH1 protein
and Escherichia coli MutT protein. In the presence of Mg(II), the natural
activator of 8-oxo-dGTPases, all four metals were found to inhibit both
enzymes. For MTH1, the IC50 values (+/- SE; n = 3-4) were 17 +/- 2 microM
for Cu(II), 30 +/- 8 microM for Cd(II), 376 +/- 71 microM for Co(II) and
801 +/- 97 microM for Ni(II). For MutT, they were 60 +/- 6 microM for
Cd(II), 102 +/- 8 microM for Cu(II), 1461 +/- 96 microM for Ni(II) and 8788
+/- 1003 microM for Co(II). Thus, Cu(II) and Cd(II) emerged as much
stronger inhibitors than Ni(II) and Co(II), and MTH1 appeared to be
generally more sensitive to metal inhibition than MutT. Interestingly, in
the absence of Mg(II), the activity of the enzymes could be restored by
Co(II) to 73% of that with Mg(II) alone for MutT, and 34% for MTH1, the
other metals being much less or non-effective. The difference in
sensitivity to metal inhibition between the two enzymes may reflect the
differences in the amino acid ligands, especially the cysteine ligand,
outside their evolutionarily conserved Mg(II)-binding active sites, which
might indicate predominantly non-competitive or uncompetitive mechanism of
the inhibition. The overall results suggest that inhibition of 8-oxo-
dGTPases may be involved in the mechanisms of induction of the 8-
oxoguanine lesion in DNA by the metal ions studied, especially the non-
redox-active Cd(II) cation.
相似文献
13.
A search for children presenting with signs or symptoms of cardiac rhabdomyomas was made through members of the paediatric section of the British Cardiac Society in order to establish their birth incidence, presenting features, clinical course, and the frequency of a concurrent diagnosis of tuberous sclerosis. Fifteen children were identified and 12 had tuberous sclerosis (80%). Heart failure was the presentation in six, five of whom died; six presented because of a murmur and three because of arrhythmias. The prevalence of echocardiographic evidence of cardiac rhabdomyomas in a population of patients with tuberous sclerosis was established. Twenty individuals had echocardiography and eight had echodensities consistent with cardiac rhabdomyomas. It is concluded that the minimum birth incidence for children presenting because of the effects of cardiac rhabdomyomas is 1/326,000 and a minimum of 80% have tuberous sclerosis. In a population of patients with tuberous sclerosis a minimum of 60% under 18 years have cardiac rhabdomyomas. 相似文献
14.
To determine the outcome of congenital lung abnormalities, data were collected retrospectively between January 1991 and December 1996 on any foetus found to have a lung lesion on antenatal ultrasound. A total of 23 foetuses had lung lesions on antenatal ultrasound. In two foetuses the antenatal ultrasound showed bilateral enlarged "bright" echogenic lungs with evidence of hydrops. Both pregnancies were terminated and tracheal atresia was confirmed. In 15 foetuses the antenatal ultrasound appearance was of a unilateral "bright" echogenic lung. There was one case of bronchial atresia and two cases of congenital lobar emphysema, which all had surgery. In nine cases there was a reduction in the size of the lesion on serial antenatal ultrasounds and no lesion was detected after birth. In three cases a small lesion was present after birth on chest radiography. In six foetuses the antenatal ultrasound appearance was of unilateral cystic or mixed cystic and echogenic lung lesions. Two pregnancies were terminated; both had congenital cystic adenomatoid malformation. Four pregnancies were continued and three infants had surgery soon after birth and were confirmed to have had congenital cystic adenomatoid malformation. One infant has been managed conservatively. In conclusion, a definitive diagnosis cannot usually be made antenatally. A large lesion on initial scan does not necessarily predict a poor outcome. The natural history of small asymptomatic postnatal lesions is unknown and a long-term prospective study is needed to determine the outcome of these lesions. 相似文献
15.
16.
Regional myocardial dysfunction: evaluation of patients with prior myocardial infarction with fast CT 总被引:1,自引:0,他引:1
Lipton MJ; Farmer DW; Killebrew EJ; Bouchard A; Dean PB; Ringertz HG; Higgins CB 《Radiology》1985,157(3):735-740
A prototype ultrafast cine computed tomographic (CT) scanner, designed specifically for cardiac imaging, was used to evaluate a preliminary series of patients with prior myocardial infarction (n = 21) and a control group without coronary artery disease (n = 5). Multilevel 50-msec CT scan exposures were obtained during peripheral intravenous bolus injections of contrast medium. A comparison was made between cine-CT scans and standard left ventriculographic images in assessing segmental left ventricular motion. Results indicate that cine CT, performed at sufficiently rapid speeds (20 scans per second) to allow useful analysis of regional ventricular wall motion, can provide adequate image quality. Analysis of 110 segments revealed a good correlation (90.9%) between the two techniques in characterizing normal from abnormal regional wall motion. Cine CT, based on this initial study, demonstrates considerable potential for evaluating not only cardiac chamber dimensions but also segmental wall dynamics. 相似文献
17.
O'Brien MF Connolly SS Kelly DG O'Brien A Quinlan DM Mulvin DW 《Irish journal of medical science》2004,173(1):23-26
Background Patients with prostate cancer with a pre-operative prostate-specific antigen (PSA) τ;15ng/ml who undergo radical retropubic
prostatectomy (RRP) generally do not have a good outcome, yet may have organ-confined cancer and should be offered the option
of surgery.
Aim To assess the outcome of patients who underwent RRP with a pre-operative PSA ≥ 15ng/ml.
Methods Thirty-four patients, mean pre-operative PSA: 25.46ng/ml (15.03–76.6) and mean Gleason score: 6.4 (5–9) were assessed.
Results Two groups were identified. Group I: 41% (14/34) have no biochemical recurrence to mean follow up of 58 months (30–106).
Mean PSA: 18.8ng/ml (15.03–25.84). Mean Gleason score: 6.1 (5–7). Clinical stage: T1c in 80%. No patient had seminal vesicle
or lymph node involvement. Group II: 59% (20/34) have biochemical recurrence or died (3) from their disease to mean follow
up of 66 months (36–98). Mean PSA: 28.9ng/ml (15.28–76.6). Mean Gleason score: 6.7 (5–9). Clinical stage: T1c in 25%. Eleven
patients had seminal vesicle (8) involvement or positive lymph nodes (3) or both (2).
Conclusion RRP seems feasible in patients whose pre-operative PSA is between 15 and 25ng/ml with stage T1c, Gleason score ≤ 7 and negative
lymph node frozen section. 相似文献
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