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91.
Although there have been great advances in cancer diagnosis in recent years, it remains difficult to transfer tumor location information from cross-sectional computed tomographic (CT) scans or magnetic resonance images to the simulation and verification films used in planning radiotherapy. A newly developed system uses radioopaque markers attached to the patient as reference points. These markers are identified on both CT scans and simulation films and their locations entered into the treatment planning computer. The tumor and any desired normal structures are then outlined manually on each CT section. Transparent overlays produced by the computer show the position of the reference markers and tumor outlines for any combination of gantry angles and source-film distance. Because the overlays are scaled to the simulation films, the reference points enable precise alignment of overlay and film. The tumor outline thus appears on the simulation or verification films exactly as it is "seen" by the therapy beam, making field verification straightforward and accurate, even on oblique films. 相似文献
92.
EA Mitchell BJ Taylor RP Ford AW Stewart DM Becroft JM Thompson R Scragg IB Hassall DM Barry EM Allen 《Archives of disease in childhood》1993,68(4):501-504
The association between dummy use and sudden infant death syndrome (SIDS) was investigated in 485 deaths due to SIDS in the postneonatal age group and compared with 1800 control infants. Parental interviews were completed in 87% of subjects. The prevalence of dummy use in New Zealand is low and varies within New Zealand. Dummy use in the two week period before death was less in cases of SIDS than in the last two weeks for controls (odds ratio (OR) 0.76, 95% confidence interval (CI) 0.57 to 1.02). Use of a dummy in the last sleep for cases of SIDS or in the nominated sleep for controls was significantly less in cases than controls (OR 0.44, 95% CI 0.26 to 0.73). The OR changed very little after controlling for a wide range of potential confounders. It is concluded that dummy use may protect against SIDS, but this observation needs to be repeated before dummies can be recommended for this purpose. If dummy sucking is protective then it is one of several factors that may explain the higher mortality from SIDS in New Zealand than in other countries, and may also explain in part the regional variation within New Zealand. 相似文献
93.
Structurally diverse molecular deletions in the beta-globin gene cluster exhibit an identical phenotype on interaction with the beta S- gene 总被引:3,自引:0,他引:3
We have characterized a new deletion that increases hemoglobin F synthesis in an American black woman who is doubly heterozygous for this mutation and the beta S-gene. The 5' endpoint is 2.4 +/- 0.1 kilobases (kb) upstream from the delta-globin gene, and the 3' endpoint is 0.2 +/- 0.1 kb downstream from the beta-globin gene; the deletion is 12 kb long. Both members of the Alu moderately repetitive DNA sequence family, normally present upstream from the delta-globin gene, are preserved. The patient is asymptomatic with a mild anemia and 24.8% HbF. The patient's husband and daughter have a similar clinical syndrome, with HbF levels of 22.4% and 25.4%, respectively. Both husband and daughter are doubly heterozygous for the beta S-gene and the Ghana type of hereditary persistence of fetal hemoglobin (HPFH) deletion (HPFH-2). The 5' end of this deletion is in the psi beta-gene, and its total length is more than 70 kb. All three members of the family have normocytic red cells, of which 95% or more are F cells as detected by immunofluorescence. Previous studies have shown that culture of the erythroid progenitors (BFU-E) from both types of these compound heterozygotes in the presence of fetal sheep serum, rich in "switching factor," resulted in complete suppression of HbF synthesis. Although the newly described deletion resembles the Sicilian type of delta beta-thalassemia by its size and preservation of the Alu sequences, the clinical and biological phenotype produced by its interaction with the beta S-gene is very similar to that of the HPFH- type deletion. 相似文献
94.
L Meyer J Mailloux S Marcoux P Blanchet F Meyer 《Acta obstetricia et gynecologica Scandinavica》1987,66(7):643-647
Risks to the mother and newborn associated with the use of the Kobayashi Silastic vacuum extractor (n = 293) were compared with those associated with the use of low forceps (n = 468) in a retrospective chart review. Third or fourth degree perineal tears and vaginal and cervical lacerations were all observed less frequently among women delivered with the vacuum extractor. The need for post-partum bladder catheterization was also reduced for these women. Babies born by the means of the vacuum extractor ran an increased risk of cephalhematoma and neonatal jaundice. No difference in major neonatal morbidity was observed between the two groups. The Kobayashi instrument appears to be a useful alternative to forceps in low vaginal instrumental deliveries. 相似文献
95.
Gender and the sudden infant death syndrome 总被引:1,自引:0,他引:1
Abstract A nationwide case-control study compared the prevalence and magnitude of risk factors for sudden infant death syndrome (SIDS) in male and female infants. The risk factors of SIDS and their magnitude for males and females are very similar. After adjustment for potential confounders male infants had a 1.42-fold (95% CI = 1.04, 1.94) increased risk of SIDS compared with females. Risk factors identified in most epidemiological studies are not the reason for the increased SIDS mortality seen in male infants. 相似文献
96.
M Chandra G K Clemons M McVicar B Wilkes P A Bluestone L U Mailloux R T Mossey 《American journal of kidney diseases》1988,12(3):208-213
Serum erythropoietin (Ep) levels were measured by radioimmunoassay in 70 patients with end-stage renal disease (ESRD) to evaluate the influence of the mode of dialysis on the relationship between serum Ep levels and the severity of anemia. Thirty-five patients were on hemodialysis (HD), seven were on intermittent peritoneal dialysis (IPD), and 28 were on continuous ambulatory peritoneal dialysis (CAPD). Compared to HD, CAPD patients had higher serum Ep (CAPD), 46.1 +/- 13.4 v HD, 16.9 +/- 2.2 mU/mL) and hematocrit (CAPD, 33.9 +/- 2.5 v HD, 24.8 +/- 1.4%; P less than 0.05). The Ep and Hct values for IPD patients were intermediate between the other two groups. Serum Ep levels were higher in CAPD patients in the first 4 weeks of initiation of CAPD (144 +/- 35 mU/mL, n = 6) than later (39 +/- 6.4 mU/mL, n = 24). A significant fluctuation in serum Ep and Hct values was noted in patients on all three modes of dialysis, when multiple samples were obtained at different time intervals. There was a weak correlation between serum Ep and Hct in the three groups of dialysis patients; r = 0.36, P less than 0.005. The data suggest that CAPD provides a better biochemical milieu for Ep production and responsiveness than HD treatment of ESRD. 相似文献
97.
RP Ford EA Mitchell AW Stewart R Scragg BJ Taylor 《Archives of disease in childhood》1997,77(1):54-55
One component of the Back to Sleep campaign to reduce the risk of sudden infant death syndrome (SIDS) is the recommendation that parents seek medical attention if their infant is unwell. The aim of this study was to investigate of SIDS could in part be explained by sick infants not getting appropriate medical care. Data on symptoms of illness and on acute medical contacts made for infants dying from SIDS (n = 390) within two weeks of their death were compared with those from a randomly selected group of control infants (n = 1592). SIDS cases had more severe illness than controls (odds ratio (OR) = 3.43; 95% confidence interval (CI) = 1.69 to 5.38), and were more likely to have seen a general practitioner (OR = 1.37; 95% CI = 1.09 to 1.73) or attended hospital (OR = 3.43, 95% CI = 1.09 to 1.73). Only 1.3% of all SIDS cases had symptoms suggesting severe illness and had not seen a general practitioner. A lack of medical contacts in the two weeks before death does not contribute to the risk of SIDS. 相似文献
98.
Platelet-associated IgG in patients with lymphoma 总被引:2,自引:0,他引:2
Levels of platelet-associated IgG (PA-IgG) were studied in 72 patients with Hodgkin's (HD) and non-Hodgkin's lymphoma (NHL). Thirty-nine percent of patients with HD and 20% of patients with NHL had elevated PA-IgG levels. There was a positive correlation between disease activity and the presence of PA-IgG in HD and NHL. In patients with HD, PA-IgG strongly correlated with extent of disease and may serve as a marker of disease activity. PA-IgG may have facilitated platelet destruction in 5 of 11 thrombocytopenic patients with HD and increased PA-IgG and in 2 patients with HD and increased PA-IgG who developed severe thrombocytopenia when treated with chemotherapy. 相似文献
99.
Australia has a universal infant pneumococcal conjugate vaccination program and until recently a universal pneumococcal polysaccharide vaccine program for non-Indigenous adults aged ≥65 years and Indigenous adults aged ≥50 years. We documented the impacts of infant and adult vaccination programs on the epidemiology of invasive pneumococcal disease (IPD) in Indigenous and non-Indigenous adults.IPD notifications from the National Notifiable Disease Surveillance System were analysed from 2002 to 2017, grouped by age, vaccine serotype group and Indigenous status. Since the universal funding of infant and elderly pneumococcal vaccination programs in January 2005, total IPD decreased by 19% in non-Indigenous adults aged ≥65 years but doubled in Indigenous adults aged ≥50 years. Vaccine uptake was suboptimal in both groups but lower in Indigenous adults. IPD due to the serotypes contained in the pneumococcal conjugate vaccines (PCV) except for serotype 3 declined markedly over the study period but were replaced by non-PCV serotypes. Serotype 3 is currently the most common in older adults. In the populations eligible for the adult 23-valent pneumococcal polysaccharide vaccine (23vPPV) program, IPD rates due to its exclusive serotypes increased to a lower extent than non-vaccine types. In 2017, non-vaccine serotypes accounted for most IPD in the older population eligible for the 23vPPV program, while it's eleven exclusive serotypes accounted for the majority of IPD in younger adults.Infant and adult pneumococcal vaccination programs in Australia have shaped the serotype-specific epidemiology of IPD in older adults. IPD remains a significant health burden for the Indigenous population. Herd immunity impact is clear for PCV serotypes excluding serotype 3 and serotype replacement is evident for non-PCV serotypes. The adult 23vPPV immunisation program appears to have partially curbed replacement with IPD due to its eleven exclusive serotypes, highlighting a potential benefit of increasing adult 23vPPV coverage in Australia. 相似文献
100.
To gain insight into the mammalian liver to kidney erythropoietin (Ep) switch, we heterotopically transplanted livers from preswitch, switched, and postswitch fetal and newborn lambs into normal adult sheep. Recipients' serum Ep and circulating reticulocyte levels were serially determined until rejection of the graft and compared with identical samples from sham-operated control adult ewes. Transplantation of preswitch and switched fetal livers caused an impressive rise in recipients' serum Ep activity and provoked a corresponding increase in reticulocytosis. In contrast, Ep activity and reticulocyte counts did not change from preoperative levels in adult ewes transplanted with postswitch livers or in the sham-operated controls. The production of Ep by the preswitch fetal liver in the adult environment was not dependent on the presence or absence of host kidneys and was stimulated by anemic hypoxia. These results suggest that the fetal liver is capable of producing relatively large amounts of Ep activity, and the production of Ep can be maintained in the adult environment in the presence of functional adult kidneys. This argues against suppression of liver Ep production by renal Ep, or some other factor in the postnatal environment, and suggests that the liver to kidney switch of Ep production during ontogeny may represent a genetically determined event. 相似文献