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We retrospectively reviewed 175 patients (191 hips) who had undergone primary cemented total hip replacement between November 1992 and November 1995 using a collarless polished double-tapered femoral component after a minimum of ten years (mean 11.08; 10 to 12.8). All stems were implanted using contemporary cementing techniques with a distal cement restrictor, pressurised lavage, retrograde cementing with a gun and proximal pressurisation. Clinical outcome was assessed using the Harris Hip score. Radiological analysis was performed on calibrated plain radiographs taken in two planes. Complete radiological data on 110 patients (120 hips) and clinical follow-up on all the surviving 111 patients (122 hips) was available. The fate of all the hips was known.At final follow-up, the mean Harris Hip score was 86 (47 to 100), and 87 of 116 patients (75%) had good or excellent scores. Survival with revision of the stem for aseptic loosening as the endpoint was 100%; and survival with revision of the stem for any reason was 95.9% (95% confidence interval 87.8 to 96.8) at ten years. All the stems subsided vertically at the stem-cement interface in a predictable pattern, at an overall mean rate of 0.18 mm per year (0.02 to 2.16), but with a mean rate of 0.80 mm (0.02 to 2.5) during the first year. The mean total subsidence was 1.95 mm (0.21 to 24). Only three stems loosened at the cement-bone interface. There was excellent preservation of proximal femoral bone stock. There was a high incidence of Brooker III and IV heterotopic ossification affecting 25 patients (22%).The collarless polished tapered stem has an excellent clinical and radiological outcome at a minimum of ten years’ follow-up. The pattern and magnitude of subsidence of the stem within the cement mantle occurred in a predictable pattern, consistent with the design philosophy.

We determined the ten-year life expectancy of 5831 patients who had undergone 6653 elective primary total hip replacements at a regional orthopaedic centre between April 1993 and October 2004. Using hospital, general practitioner and the local health authority records, we recorded the dates of death for those who died following surgery.The mean age at operation was 67 years (13 to 96) with a male:female ratio of 2:3. Of 1154 patients with a ten-year follow-up 340 (29.5%) had died a mean of 5.6 years (0 to 10) after surgery. Using Kaplan-Meier curves, the ten-year survival was 89% in patients under 65 years at surgery, 75% in patients aged between 65 and 74 years, and 51% in patients over 75.The standardised mortality rates were considerably higher for patients under 45 years, 20% higher for those between 45 and 64 years, and steadily reduced in patients aged 65 and over.The survival of cemented hip replacement derived from the Swedish Hip Arthroplasty Register Annual Report 2004 exceeds the life expectancy of patients over the age of 60 in our area, suggesting that cemented hip replacement is the procedure of choice in this population.

We reviewed 142 consecutive primary total hip replacements implanted into 123 patients between 1988 and 1993 using the Exeter Universal femoral stem. A total of 74 patients (88 hips) had survived for ten years or more and were reviewed at a mean of 12.7 years (10 to 17). There was no loss to follow-up.The rate of revision of the femoral component for aseptic loosening and osteolysis was 1.1% (1 stem), that for revision for any cause was 2.2% (2 stems), and for re-operation for any cause was 21.6% (19 hips). Re-operation was because of failure of the acetabular component in all but two hips.All but one femoral component subsided within the cement mantle to a mean of 1.52 mm (0 to 8.3) at the final follow-up. One further stem had subsided excessively (8 mm) and had lucent lines at the cement-stem and cement-bone interfaces. This was classified as a radiological failure and is awaiting revision. One stem was revised for deep infection and one for excessive peri-articular osteolysis. Defects of the cement mantle (Barrack grade C and D) were found in 28% of stems (25 hips), associated with increased subsidence (p = 0.01), but were not associated with endosteal lysis or failure.Peri-articular osteolysis was significantly related to the degree of polyethylene wear (p < 0.001), which was in turn associated with a younger age (p = 0.01) and male gender (p < 0.001).The use of the Exeter metal-backed acetabular component was a notable failure with 12 of 32 hips (37.5%) revised for loosening. The Harris-Galante components failed with excessive wear, osteolysis and dislocation with 15% revised (5 of 33 hips). Only one of 23 hips with a cemented Elite component (4%) was revised for loosening and osteolysis.Our findings show that the Exeter Universal stem implanted outside the originating centre has excellent medium-term results.

OBJECTIVE: To determine the risk of lung cancer associated with exposure at home to the radioactive disintegration products of naturally occurring radon gas Design Collaborative analysis of individual data from 13 case-control studies of residential radon and lung cancer. Setting Nine European countries. Subjects 7148 cases of lung cancer and 14 208 controls. MAIN OUTCOME MEASURES: Relative risks of lung cancer and radon gas concentrations in homes inhabited during the previous 5-34 years measured in becquerels (radon disintegrations per second) per cubic metre (Bq/m3) of household air. RESULTS: The mean measured radon concentration in homes of people in the control group was 97 Bq/m3, with 11% measuring > 200 and 4% measuring > 400 Bq/m3. For cases of lung cancer the mean concentration was 104 Bq/m3. The risk of lung cancer increased by 8.4% (95% confidence interval 3.0% to 15.8%) per 100 Bq/m3 increase in measured radon (P = 0.0007). This corresponds to an increase of 16% (5% to 31%) per 100 Bq/m3 increase in usual radon—that is, after correction for the dilution caused by random uncertainties in measuring radon concentrations. The dose-response relation seemed to be linear with no threshold and remained significant (P = 0.04) in analyses limited to individuals from homes with measured radon < 200 Bq/m3. The proportionate excess risk did not differ significantly with study, age, sex, or smoking. In the absence of other causes of death, the absolute risks of lung cancer by age 75 years at usual radon concentrations of 0, 100, and 400 Bq/m3 would be about 0.4%, 0.5%, and 0.7%, respectively, for lifelong non-smokers, and about 25 times greater (10%, 12%, and 16%) for cigarette smokers. CONCLUSIONS: Collectively, though not separately, these studies show appreciable hazards from residential radon, particularly for smokers and recent ex-smokers, and indicate that it is responsible for about 2% of all deaths from cancer in Europe.

Background We have examined secular trends in age- and sex-specific prescribing of antidepressants to determine whether these mirror changes in other population measures of mental health.Method An analysis was carried out of age- and sex-specific rates of antidepressant prescribing by a representative sample or panel of UK general practitioners (GPs) in the period 1975-1998.Results The number of antidepressant prescriptions issued increased more than twofold in the period 1975-1998 and, in 1998, a total of 23.4 million antidepressant prescriptions were issued by GPs in the United Kingdom. Rates of antidepressant prescribing increased markedly in all age and sex groups with as much as a threefold increase in the older age groups. With the exception of 12-19-year-olds, these increases have been more marked in males, although absolute levels of prescribing are still at least two times higher in females.Conclusions Antidepressant prescribing has increased in all age and sex groups. This indicates either that there have been changes in the presentation, recognition and management of depression in general practice or that the prevalence of depression has increased, or a combination of these two phenomena. The higher prescribing rate in females is in keeping with evidence from psychiatric morbidity surveys suggesting that women experience higher levels of psychiatric morbidity than men. Decreases in the ratio of female to male prescribing, however, support other data indicating that, relative to females, the mental health of young males has declined in recent years. Changes in patterns of help-seeking may also contribute to the observed trends.

Studies of underground miners occupationally exposed to radon have consistently demonstrated an increased risk of lung cancer in both smokers and non-smokers. Radon exposure also occurs elsewhere, especially in houses, and estimates based on the findings for miners suggest that residential radon is responsible for about one in 20 lung cancers in the UK, most being caused in combination with smoking. These calculations depend, however, on several assumptions and more direct evidence on the magnitude of the risk is needed. To obtain such evidence, a case-control study was carried out in south-west England in which 982 subjects with lung cancer and 3185 control subjects were interviewed. In addition, radon concentrations were measured at the addresses at which subjects had lived during the 30-year period ending 5 years before the interview. Lung cancer risk was examined in relation to residential radon concentration after taking into account the length of time that subjects had lived at each address and adjusting for age, sex, smoking status, county of residence and social class. The relative risk of lung cancer increased by 0.08 (95% CI -0.03, 0.20) per 100 Bq m(-3) increase in the observed time-weighted residential radon concentration. When the analysis was restricted to the 484 subjects with lung cancer and the 1637 control subjects with radon measurements available for the entire 30-year period of interest, the corresponding increase was somewhat higher at 0.14 per 100 Bq m(-3) (95% CI 0.01, 0.29), although the difference between this group and the remaining subjects was not statistically significant. When the analysis was repeated taking into account uncertainties in the assessment of radon exposure, the estimated increases in relative risk per 100 Bq m(-3) were larger, at 0.12 (95% CI -0.05, 0.33) when all subjects were included and 0.24 (95% CI -0.01, 0.56) when limited to subjects with radon measurements available for all 30 years. These results are consistent with those from studies of residential radon carried out in other countries in which data on individual subjects have been collected. The combined evidence suggests that the risk of lung cancer associated with residential radon exposure is about the size that has been postulated on the basis of the studies of miners exposed to radon.

The construction and operation of an apparatus is described which enables α-antitrypsin to be isolated from human serum by preparative electrophoresis in polyacrylamide gel. The initial pass through the chamber yields a fraction that is predominantly albumin and several α1-proteins. After removal of albumin by affinity chromatography, a second pass through the chamber separates the individual α1-proteins. A volume of 50 ml of serum may be accommodated by the chamber, and the recovery of activity in each step is greater than 60%. The entire procedure may be completed in 36 hrs.

A simple form of measurement error model for explanatory variables is studied incorporating classical and Berkson cases as particular forms, and allowing for either additive or multiplicative errors. The work is motivated by epidemiological problems, and therefore consideration is given not only to continuous response variables but also to logistic regression models. The possibility that different individuals in a study have errors of different types is also considered. The relatively simple estimation procedures proposed for use with cohort data and case‐control data are checked by simulation, under the assumption of various error structures. The results show that even in situations where conventional analysis yields slope estimates that are on average attenuated by a factor of approximately 50 per cent, estimates obtained using the proposed amended likelihood functions are within 5 per cent of their true values. The work was carried out to provide a method for the analysis of lung cancer risk following residential radon exposure, but it should be applicable to a wide variety of situations. © 1998 John Wiley & Sons, Ltd.

In this paper we explore the arithmetic correspondence between, on the one hand, (isogeny classes of) elliptic curves E defined over an imaginary quadratic field K of class number one, and on the other hand, rational newforms F of weight two for the congruence subgroups $ {\Gamma _0}(\mathfrak{n})$n is an ideal in the ring of integers R of K. This continues work of the first author and forms part of the Ph.D. thesis of the second author. In each case we compute numerically the value of the L-series $ L(F,s)$ and compare with the value of $ L(E,1)$ $ L(F,1) = 0$ has a point of infinite order. Several examples are given in detail from the extensive tables computed by the authors.

A simple form of measurement error model for explanatory variables is studied incorporating classical and Berkson cases as particular forms, and allowing for either additive or multiplicative errors. The work is motivated by epidemiological problems, and therefore consideration is given not only to continuous response variables but also to logistic regression models. The possibility that different individuals in a study have errors of different types is also considered. The relatively simple estimation procedures proposed for use with cohort data and case-control data are checked by simulation, under the assumption of various error structures. The results show that even in situations where conventional analysis yields slope estimates that are on average attenuated by a factor of approximately 50 per cent, estimates obtained using the proposed amended likelihood functions are within 5 per cent of their true values. The work was carried out to provide a method for the analysis of lung cancer risk following residential radon exposure, but it should be applicable to a wide variety of situations. © 1998 John Wiley & Sons, Ltd.

Liquid ion exchange has replaced several solid ion exchange and extraction procedures at the Savannah River Plant (SRP). The principal advantage of the method is rapidity; many ions exchange from one liquid phase to the other within a few seconds. Separation procedures are relatively simple; an acidic aqueous sample is mixed with an equal volume of liquid ion exchange reagent diluted in an inert solvent. The cation exchanger is di-2-ethyl-hexyl phosphoric acid (HDEHP) and the anion exchanger is tri-isooctylamine (TIOA). The ion exchange characteristics of thirty-seven elements were determined. Variations in exchangers, acid concentrations and stripping solutions resulted in separation of specific radionuclides from environmental and bioassay samples. HDEHP and TIOA are used to separate radionuclides with similar gamma energies prior to spectrometric analyses. A complex mixture of 141,144Ce and 239Np, 51Cr and 131I, 58Co and 140Ba La, for instance, which previously required 24 hr for analysis, can now be separated and analyzed in 1 hr. TIOA is a more efficient absorber of all forms of iodine than chloroform, the commonly used iodine absorber. TIOA is also used instead of tributyl phosphate extraction for alpha emitters. Many cations exchange to HDEHP from dilute acid solutions and this technique is used to concentrate radionuclides from environmental and bioassay samples.

O objectivo desta análise foi determinar o risco de neoplasia do pulmão associado à exposição em casa à radioactividade produzida pelo radão, gás que ocorre naturalmente na natureza.

Numerous genetically similar cattle for use in research or teaching can be produced with chromatin transfer technology (Sullivan et al. 2004 Biol. Reprod. 70, 146?153). Miniature cattle can provide advantageous biotechnological models for teaching and study of human and animal diseases. Miniature cattle are approximately one fourth the size of standard cattle and, therefore, represent a potentially less expensive, safer, and more easily managed animal model. Our limited attempts to reproduce miniature cattle via in vivo and in vitro production of embryos resulted in poor response to superovulation and logistical challenges in recovering embryos or oocytes due to the small size of the animals. Thus, the purpose of this study was to evaluate the potential of embryos derived by chromatin transfer from fibroblasts of a miniature cow and cytoplasts from cows of standard size to produce viable offspring after transfer into recipient cows of standard size. The donor of somatic cells was a heifer that weighed 7.7 kg at birth. Chromatin transfer resulted in 19% (82/428) blastocyst formation. A total of 66 cloned blastocysts (65 excellent/good quality, 1 fair quality) were transferred into 26 synchronized recipients. While ultrasound revealed 13 pregnancies prior to 67 days of gestation, only 4 pregnancies of 5 fetuses were maintained beyond 100 days. Parturition was induced with dexamethasone and prostaglandin on Day 286 of gestation. One singleton (12.3 kg) and a set of twins (10.2 and 11.1 kg) were healthy at birth and normal at 1 week of age. Two fully developed singletons, weighing 21.4 and 13.6 kg, died in utero. The latter fetus exhibited a fixed dorsolateral deviation of the neck that complicated delivery despite a caudal obstetrical presentation. No abnormalities were noted in the size or structure of any placenta. Our results indicate that healthy miniature calves can be gestated by recipient cows of standard size after transfer of embryos derived by chromatin transfer. Unfortunately, the fetal wastage, fetal anomalies, and stillbirths observed with standard sized cattle also may occur.

Numerous genetically similar cattle for use in research or teaching can be produced with chromatin transfer technology (Sullivan et al. 2004 Biol. Reprod. 70, 146?153). Miniature cattle can provide advantageous biotechnological models for teaching and study of human and animal diseases. Miniature cattle are approximately one fourth the size of standard cattle and, therefore, represent a potentially less expensive, safer, and more easily managed animal model. Our limited attempts to reproduce miniature cattle via in vivo and in vitro production of embryos resulted in poor response to superovulation and logistical challenges in recovering embryos or oocytes due to the small size of the animals. Thus, the purpose of this study was to evaluate the potential of embryos derived by chromatin transfer from fibroblasts of a miniature cow and cytoplasts from cows of standard size to produce viable offspring after transfer into recipient cows of standard size. The donor of somatic cells was a heifer that weighed 7.7 kg at birth. Chromatin transfer resulted in 19% (82/428) blastocyst formation. A total of 66 cloned blastocysts (65 excellent/good quality, 1 fair quality) were transferred into 26 synchronized recipients. While ultrasound revealed 13 pregnancies prior to 67 days of gestation, only 4 pregnancies of 5 fetuses were maintained beyond 100 days. Parturition was induced with dexamethasone and prostaglandin on Day 286 of gestation. One singleton (12.3 kg) and a set of twins (10.2 and 11.1 kg) were healthy at birth and normal at 1 week of age. Two fully developed singletons, weighing 21.4 and 13.6 kg, died in utero. The latter fetus exhibited a fixed dorsolateral deviation of the neck that complicated delivery despite a caudal obstetrical presentation. No abnormalities were noted in the size or structure of any placenta. Our results indicate that healthy miniature calves can be gestated by recipient cows of standard size after transfer of embryos derived by chromatin transfer. Unfortunately, the fetal wastage, fetal anomalies, and stillbirths observed with standard sized cattle also may occur.