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101.
YL Lau LCK Low R Yung KW Ng CW Leung WH Lee A Ho SJ Oppenheimer Hong Kong Hib Study Group 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(2):173-176
A 5-year territory-wide retrospective survey of invasive Haemophilus influenzae type b diseases was conducted in Hong Kong. Between 1986 and 1990, 57 cases (28 male) were recorded in children less than 12 years old (37 cases of meningitis, 9 of septicaemia and 11 of bacteraemic pneumonia). The annual incidence for children less than 5 years old was 2.7 per 105 (95% confidence interval (CI) 2.0–3.5). Of the 57 cases, 39 were Chinese and 18 non-Chinese (7 Vietnamese refugees, 6 Caucasians, 5 others). The annual incidence in Vietnamese refugees less than 5 years old was 42.7 per 105 (95% CI 17.2–87.9), giving a relative risk of 18.5 (95% CI 8.3–41.0). Chinese patients (68%) were under-represented as Chinese accounted for at least 94% of the population. Moreover, 14 of the 39 Chinese patients had pre-existing medical problems, compared with only 1 of the 18 non-Chinese patients (p = 0.022). 相似文献
102.
There is concern that our reproductive systems are exposed to environmental
hazards. A number of potential monitors of these hazards have been proposed
(reported rates of cryptorchidism, testicular cancer, hypospadias,
dizygotic twinning, sperm count, ectopic pregnancy and sex ratios). To
discover whether these are monitoring the same hazards, secular movements
in these measures are considered here. It is suggested that the secular
movements of cryptorchidism and hypospadias are insufficiently reliable to
give guidance on the movements of such hazards as cause them. With one
possible exception, rates have not moved in parallel and so, in general,
they are not monitoring the same hazards. The exception is dizygotic
twinning rates and sperm counts which may have a lagged correlation. If
this is true, it may be important and throw light on the hitherto
unexplained movements of both. The hazards themselves are largely
unidentified, but may be presumed to include: (i) the well-publicized rise
in environmental oestrogens; (ii) an increasing number of women with
suboptimal oestrogens (because of dieting and arduous exercise); and (iii)
hormonal consequences of these two opposing trends, e.g. an increasing
number of women with suboptimal androgens (possibly accounting for the
increasing rates of cryptorchidism and testicular cancer).
相似文献
103.
OBJECTIVE: Results from previous studies have shown that pre- and perinatal exposure to lead enhances susceptibility of rats to development of dental carieS. A possible explanation for this phenomenon may be that lead complexes with fluoride and renders F insoluble and unable to exert its cariostatic effects. MATERIALS AND METHODS: Thus, to explore this hypothesis, 48 desalivated Sprague-Dawley rats were placed in a König-Höfer programmed feeder and received 17 meals of powdered sucrose daily, and water ad libitum as follows: group (1) plain sucrose and sterile distilled water (SDW); (2) sucrose containing 15 ppm F and SDW; (3) sucrose containing 15 ppm F and 10 ppm Pb water; (4) sucrose containing 15 ppm F and 25 ppm Pb water. RESULTS: The highest smooth-surface, sulcal surface caries and severity scores were observed in group 1.Animals that were exposed to fluoride showed reduced smooth-surface caries and severity scores.S. sobrinus counts did not differ among the groups. CONCLUSION: Lead did not interfere with the protective effect of fluoride in the conditions of the present study. 相似文献
104.
Peripheral cholangiocarcinoma and clonorchiasis: CT findings 总被引:8,自引:0,他引:8
Sixteen patients with peripheral cholangiocarcinoma of the liver were examined with computed tomography (CT). None of the 16 patients presented with jaundice or had documented cirrhosis. On scans obtained both before and after the injection of contrast material, the tumors were depicted as low-attenuation masses in all cases, with wide variations in homogeneity. The tumor margin was irregular in 12 cases, and there was minimal contrast enhancement of the tumor in 14 cases. In 11 (69%) patients, CT demonstrated masses of markedly low attenuation, which corresponded to areas of diffuse microcystic change seen at histologic examination of resected specimens. In ten (63%) patients, the results of stool or intradermal tests for Clonorchis sinensis were positive. In all ten cases of clonorchiasis, mild, diffuse dilatation of the intrahepatic bile ducts was seen in addition to the low-attenuation masses, but there was no dilatation of the extrahepatic biliary tree. In five of the ten patients with clonorchiasis, stippled or aggregated, powderlike areas of high attenuation were seen on precontrast CT scans; at pathologic examination, those areas were found to be mucin. Extrahepatic metastases were demonstrated in ten (63%) patients. Peripheral cholangiocarcinoma should be the primary diagnostic consideration when these characteristic CT findings are detected in a noncirrhotic patient. 相似文献
105.
CSF rhinorrhea: detection and localization using overpressure cisternography with Tc-99m-DTPA 总被引:1,自引:0,他引:1
We performed 32 overpressure radionuclide cisternography (ORNC) studies to examine 26 patients who were clinically suspected of having cerebrospinal fluid (CSF) fistula with rhinorrhea. Fifteen (47%) of these cisternography studies were positive, and the site of the leak was identified. No leak could be demonstrated in the other 17. Of 23 examinations performed in patients who had clinically documented CSF rhinorrhea, 15 (65%) were scintigraphically positive. The rapid cephalad transit of the radionuclide bolus allowed completion of the study within 30 to 45 minutes. Seven examinations were also performed with overpressure metrizamide CT cisternography (OMCTC), and five demonstrated concordant results with the radionuclide study. Patient discomfort and side effects were minimal. We conclude that radionuclide infusion cisternography is a safe, rapid, and accurate method of investigating a suspected or proven CSF rhinorrhea and that it is complementary to metrizamide cisternography. 相似文献
106.
Extracorporeal shock wave lithotripsy (ESWL) is now the preferred method for treating most renal calculi. We designed a cassette and grid holder and a technique for filming in the water bath. The excellent film quality permits initial localization of small or faint calculi and confirmation of satisfactory fragmentation during ESWL. The technique facilitates patient treatment and throughput and should reduce the repeat treatment rate. 相似文献
107.
Tim Coleman Jim Thornton John Britton Sarah Lewis Kim Watts Michael WH Coughtrie Clare Mannion Neil Marlow Christine Godfrey 《BMC health services research》2007,7(1):2
Background
Smoking in pregnancy remains a public health challenge. Nicotine replacement therapy (NRT) is effective for smoking cessation in non-pregnant people, but because women metabolise nicotine and cotinine much faster in pregnancy, it is unclear whether this will be effective for smoking cessation in pregnancy. The NHS Health Technology Assessment Programme (HTA)-funded smoking, nicotine and pregnancy (SNAP) trial will investigate whether or not nicotine replacement therapy (NRT) is effective, cost-effective and safe when used for smoking cessation by pregnant women. 相似文献108.
109.
110.
The present report describes a modified, rapid acid-stromal method for elution of erythrocyte antibodies. With this method, potent crystal clear auto and alloantibody eluates can be produced. The simplicity of the method makes it readily adaptable to the routine serological laboratory or blood bank. In semiquantitative and quantitative studies, we have found that this method compares favorably with other antibody elution methods. With alloantibodies, the rapid acid elution method and the ether method produced the strongest eluates with the ether eluates being slightly more potent than the rapid eluated. By contrast, with autoantibodies the rapid method was clearly superior, producing much stronger IgG erythrocyte coating as judged by the 125I antiglobulin test. 相似文献