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41.
42.
Psoriasis is commonly associated with a co‐existent arthritis known as psoriatic arthritis (PsA). Although there is some treatment overlap for psoriasis and psoriatic arthritis, it is possible that dermatologists may not diagnose or treat appropriately patients who are developing psoriatic arthritis at an early stage of the disease process when joint damage may be preventable. In this article we review the criteria for diagnosis of this sero‐negative arthritis, look at the clinical indications for referral to a rheumatologist and discuss evolving treatment options relevant to both conditions.  相似文献   
43.
Case studies have shown that radon gas can accumulate within domestic properties at sufficiently high levels that it can cause lung cancer, and recent studies have suggested that this risk remains significant below the UK domestic Action Level of 200 Bq m(-3). Raised radon levels can be reduced by engineering measures, and it has been shown that domestic radon remediation programmes in UK Affected Areas can result in reduced risks to the population and can be cost-effective. We consider here the benefits and costs of the domestic radon remediation programme in Northamptonshire, UK, and consider the implications for that programme of reducing the UK Action Level below its present value. A radon remediation programme based on an Action Level above 200 Bq m(-3) will cost less and will target those most at risk, but will be less cost-effective and will lead to higher residual dose and greater risk of cancer in the remaining population. Reducing the Action Level below 200 Bq m(-3) will prevent more cancers, but at significantly higher cost. It will also be less cost-effective, because remediation of a significant number of houses with moderate radon levels will provide only a modest health benefit to occupants. Overall, a completed radon remediation programme of the type implemented in Northamptonshire is most cost-effective for an Action Level between 200 and 300 Bq m(-3). The implications for future health policy are discussed.  相似文献   
44.
Duration of human singleton pregnancy. A population-based study   总被引:2,自引:0,他引:2  
We have analysed the duration of pregnancy for singleton births in Sweden during 1976-80 by means of data from the Swedish Birth Registry. Information, which was obtained from special forms with standard questions, include date of first day of last menstrual period (LMP) and whether that date was considered reliable or not. Recording was done prospectively, starting at the first antenatal visit. In 10% of cases the dates were labelled uncertain. Information on LMP and birth dates, parity, age of mother, sex of child, and/or mode of delivery was missing in 5.5% of the singleton cases, leaving 427,581 singleton births for analysis. In cases of reliable menstrual dates, the average duration from LMP to vaginal birth was 282 days (median), 281 days (mean) and 283 days (mode), remaining constant over the years of study. One standard deviation of the mean was approximately 13 days, varying slightly with age and parity. Ten per cent of these women gave birth post term (past 294 days). The duration of cesarean section births became shorter over the years, in spite of little change in cesarean section frequency (9.5% in 1976-7 and 10.9% in 1979-80). Mothers aged 35 and over tended to give birth 2 days earlier than those below 35. Second and subsequent children of mothers below 35 had slightly shorter gestations than first-borns. Boys were born earlier than girls, on average. When LMP was unreliable, the distribution of gestational lengths was wide. We also noted a seasonal rhythmicity in average duration of pregnancy, with consistent shortening in the month of December.  相似文献   
45.
46.
There have been extensive observations that RNA containing repetitive elements accumulates in transformed cells and tumor tissues. In the present study, we first obtained result consistent with previous observations by in situ hybridization.  相似文献   
47.
OBJECT: The goals of this study were to define the incidence of seizures in children with low-grade tumors, study seizure outcome after lesionectomy in these children, and identify risk factors for poor seizure outcome, METHODS: The authors performed a retrospective chart review of children who harbored low-grade brain tumors, experienced seizures, and were treated in a single institution, Statistical analyses included step-wise as well as single-variable binary logistic regression analyses.  相似文献   
48.
A previous study from this laboratory demonstrated that treatment of pregnant mice with 3-methylcholanthrene (MC) caused lung tumors in the offspring at 1 year after birth, the incidence of which correlated with fetal inducibility of Cyp1a1. Analysis by PCR amplification and allele- specific hybridization (ASO) of paraffin-embedded tumors generated from that study revealed the presence of point mutations in exon 1 of the Ki- ras gene. This work has now been expanded by PCR amplification and ASO analysis of 31 additional lesions. Point mutations were found in 37 of the 47 (79%) lesions analyzed in this and the previous study, the majority of which were G-->T transversions in the first or second base of codon 12. The mutational spectrum appeared to be dependent on the relative stage of differentiation of the lesion, as both the incidence of mutation and type of mutation produced correlated with malignant progression. Mutations occurred in 60% of the hyperplasias, 80% of the adenomas and 100% of the adenocarcinomas. In the lesions with mutations, GLY12-->CYS12 transversions occurred in 100% of the hyperplasias, 42% of the adenomas and 14% of the adenocarcinomas. The GLY12-->VAL12 transversions occurred in none of the hyperplasias, 42% of the adenomas and 57% of the adenocarcinomas. The remaining mutations, which consisted of ASP12 transitions and ARG13 transversions, occurred only in adenomas (17%) and adenocarcinomas (29%). Between this study and our previous analyses, the identity of the mutations obtained by ASO were confirmed by sequence analysis of eight of the 37 lesions that harbored mutations at the Ki-ras gene locus. There were no differences in the type or incidence of mutations relative to the metabolic phenotype or sex of the mice. These data suggest that mutational activation of the Ki-ras gene locus is an early event in transplacental lung tumorigenesis, and that the type of mutations produced by exposure to chemical carcinogens can influence the carcinogenic potential of the tumor. This may have prognostic significance in determining the malignant progression of the neoplasm.   相似文献   
49.
Breast milk samples from three groups of Brazilian women were evaluated: G1, mothers delivering term babies of low birth weight (n=16); G2, mothers delivering preterm babies of appropriate birth weight (n = 20); G3, mothers delivering term babies of appropriate birth weight ( n = 30). Milk samples were obtained at 48 h and on the 7th, 15th, 30th and 60th days after delivery and they were analyzed for lysozyme and total IgA levels and for the presence of specific antibodies against Poliovirus types I, II, III, Rotavirus, Herpes simplex virus, Varicella zoster and Cytomegalovirus. The groups were not statistically different in relation to mother's age, parity, type of delivery or socio-economic levels. IgA levels were higher in both low-birth-weight groups (G1 & G2) compared to the control group (G3) throughout the study period. Lysozyme levels decreased up to the 15th day, increasing thereafter up to the 60th day in all groups. Specific antibodies were detected throughout the study period, with no differences among groups. We conclude that breast milk composition of mothers delivering low-birth-weight babies (G1 & G2) was similar despite the different gestational ages.  相似文献   
50.
Nyberg  DA; Mack  LA; Laing  FC; Jeffrey  RB 《Radiology》1988,167(3):619-622
Endovaginal sonography results were compared with quantitatively determined human chorionic gonadotropin (hCG) levels in 84 women referred for early pregnancy complications. Of the 27 with normal intrauterine pregnancies, an intrauterine gestational sac was prospectively identified in one of five cases (20%) in which hCG levels were below 500 IU/L (Second International Standard), four of five (80%) with hCG levels of 500-1,000 IU/L, and all 17 with hCG levels above 1,000 IU/L. In comparison, 17 of the 26 women with ectopic pregnancies (65%) had hCG levels greater than 1,000 IU/L, and none of the 26 had an intrauterine gestational sac. Endovaginal sonography demonstrated an adnexal mass and/or a gestational sac-like structure in 16 of the 17 cases (94%) in which hCG levels were above 1,000 IU/L, compared with only three of the nine (33%) with lower hCG levels (P less than .01). These findings indicate that an intrauterine gestational sac should be normally visualized with endovaginal sonography when the hCG level exceeds 1,000 IU/L, and that visualization of an extrauterine gestational sac and/or adnexal mass is significantly more likely in ectopic pregnancies when the hCG level exceeds 1,000 IU/L.  相似文献   
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