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Biomedical subjects

C A Stone

Publications and source records attributed to C A Stone.

At least 19 recordsLinked to original sources
PubMed2003

Screening for lung cancer: a systematic review and meta-analysis of controlled trials.

BACKGROUND: Lung cancer is a substantial public health problem in western countries. Previous studies have examined different screening strategies for lung cancer but there have been no published systematic reviews. METHODS: A systematic review of controlled trials was conducted to determine whether screening for lung cancer using regular sputum examinations or chest radiography or computed tomography (CT) reduces lung cancer mortality. The primary outcome was lung cancer mortality; secondary outcomes were lung cancer survival and all cause mortality. RESULTS: One non-randomised controlled trial and six randomised controlled trials with a total of 245 610 subjects were included in the review. In all studies the control group received some type of screening. More frequent screening with chest radiography was associated with an 11% relative increase in mortality from lung cancer compared with less frequent screening (RR 1.11, 95% CI 1.00 to 1.23). A non-statistically significant trend to reduced mortality from lung cancer was observed when screening with chest radiography and sputum cytological examination was compared with chest radiography alone (RR 0.88, 95% CI 0.74 to 1.03). Several of the included studies had potential methodological weaknesses. Controlled studies of spiral CT scanning have not been reported. CONCLUSIONS: The current evidence does not support screening for lung cancer with chest radiography or sputum cytological examination. Frequent chest radiography might be harmful. Further methodologically rigorous trials are required before any new screening methods are introduced into clinical practice.

Controlled Clinical Trials as Topic↗
PubMed2001

Use of colour duplex Doppler imaging in the postoperative assessment of buried free flaps.

The postoperative assessment of free flaps is essential to identify and act on signs of incipient flap failure. Where the flap is completely buried, this becomes almost impossible unless part of the flap is exteriorised or an overlying skin window is used. Alternatively, complicated and often impractical monitoring devices have been advocated, but these have failed to gain widespread acceptance. A simpler solution to this problem has been evaluated in a series of patients using colour duplex Doppler imaging. This re-appraisal of a previously reported technique has been facilitated by updated technology in diagnostic radiology. Duplex Doppler imaging was confirmed as an accurate, non-invasive, and inexpensive tool for the postoperative measurement of blood flow within the pedicles of five buried free flaps in four patients undergoing surgery in our unit.

Adult↗
PubMed2001

Validity evidence for using a general critical thinking test to measure nursing students' critical thinking.

This study examined validity evidence for using a general test of critical-thinking skills and dispositions to measure nursing students' critical-thinking abilities. Content evidence indicated strong support for the theoretical framework underlying the test but less support for the way in which the critical-thinking constructs were specifically measured. Scores related to critical-thinking skills demonstrated significant but low correlations with grade point averages, were moderately correlated with SAT scores, and were uncorrelated with scores related to critical-thinking dispositions. The evidence suggests that nursing programs may need to reconsider how critical thinking should be measured and evaluated.

Adult↗
PubMed2000

Unravelling the secrets of foetal wound healing: an insight into fracture repair in the mouse foetus and perspectives for clinical application.

This study was designed to investigate the nature of mammalian foetal fracture healing in utero. A compound 'pinch' fracture was created in the foetal mouse ulna at the end of the second trimester, prior to mineralisation, and healing observed in whole mount limbs and in histological section. Cartilaginous ends gained initial contact within a perichondrial sleeve by 24 h. Bony union was achieved within 48 h by cartilage remodelling during the phase of primary endochondral ossification in the limb, a process to which adult fracture healing aspires. The molecular response to wounding was investigated using a whole mount in situ hybridisation technique and antisense mRNA probes to three target genes (BMP-2, BMP-4 and GDF-5). These experiments failed to identify altered expression in wounded limbs compared with controls.

Animals↗
PubMed2000

Healing at skin graft donor sites dressed with chitosan.

Chitosan is a derivative of chitin, extracted from the exoskeleton of lobsters, crabs and shrimps. As a semi-permeable biological dressing, it maintains a sterile wound exudate beneath a dry scab, preventing dehydration and contamination of the wound to optimise conditions for healing. In this study, evaluation of healing at split skin graft donor sites, dressed half with chitosan and half with a conventional dressing, showed that chitosan facilitated rapid wound re-epithelialisation and the regeneration of nerves within a vascular dermis. In addition, digital colour separation analysis of donor site scars demonstrated an earlier return to normal skin colour at chitosan-treated areas.

Adolescent↗
PubMed2000

Neural tube defects in Victoria, Australia: potential contributing factors and public health implications.

OBJECTIVES: To measure population prevalence and determine potential predictors of neural tube defects. METHOD: Analysis of all births reported to a mandated collection of perinatal data, and terminations prior to 20 weeks' gestation that have been reported to a data collection of birth defects in Victoria from 1983 to 1997. Prevalence at birth and risk ratios of infant and maternal characteristics associated with neural tube defects were calculated. RESULTS: Prevalence of spina bifida has remained steady for 15 years and was 8.8/10,000 in 1997. Anencephaly increased to 7.9/10,000 in 1997. After exclusion of pregnancy terminations, the 1997 birth prevalence was 4.5/10,000 for spina bifida and 2.4/10,000 for anencephaly. Neural tube defects are identified in 1 in 1600 fetuses, the risk being significantly higher for epileptic women (Adjusted Odds Ratio (AOR) = 3.70, 95% CI 2.25-6.07), multiple births (AOR = 4.56, 95% CI 3.46-6.02), teenage mothers (AOR = 1.47, 95% CI 1.09-2.00) compared with those aged 25-29, and women with three or more previous pregnancies (AOR = 1.40, 95% CI 1.10-1.78). The risk was lower for women of East Asian (AOR = 0.70, 95% CI 0.49-1.00) and Middle Eastern origin (AOR = 0.60, 95% CI 0.35-1.02) and these differences were approaching statistical significance. CONCLUSION: Total prevalence of neural tube defects did not decline up to 1997. IMPLICATIONS: It is unlikely that targeting 'at risk' groups identified in this study would make a difference to neural tube defect incidence. However, consideration could be given to identifying larger 'at risk' groups such as those with homocysteine metabolism defects.

Confidence Intervals↗
PubMed1999

Evolution of the Emergency Management of Severe Burns (EMSB) course in the UK.

The principle of the 'golden hour' is now well established and forms the basis of a growing number of instructional courses teaching a systematic approach to the management of major trauma. In April 1997, the EMSB course, developed by the Australian and New Zealand Burn Association, was adopted by the British Burn Association to meet the needs of health professionals dealing with major burn injuries in this country. The experience of the first 13 courses following the introduction of EMSB is discussed and the course is recommended as a requirement for the training of UK plastic surgeons and plastic surgery nurses.

Burns↗
PubMed1999

Reducing non-attendance at outpatient clinics.

Outpatient non-attendance is a common source of inefficiency in a health service, wasting time and resources and potentially lengthening waiting lists. A prospective audit of plastic surgery outpatient clinics was conducted during the six months from January to June 1997, to determine the clinical and demographic profile of non-attenders. Of 6095 appointments 16% were not kept. Using the demographic information, we changed our follow-up guidelines to reflect risk factors for multiple non-attendances, and a self-referral clinic was introduced to replace routine follow-up for high risk non-attenders. After these changes, a second audit in the same six months of 1998 revealed a non-attendance rate of 11%--i.e. 30% lower than before. Many follow-up appointments are sent inappropriately to patients who do not want further attention. This study, indicating how risk factor analysis can identify a group of patients who are unlikely to attend again after one missed appointment, may be a useful model for the reduction of outpatient non-attendance in other specialties.

Appointments and Schedules↗
PubMed1998

The Hyphecan cap: a biological fingertip dressing.

An occlusive biological dressing, the Hyphecan cap, was evaluated in the management of full-thickness pulp defects of fingers and thumb in 20 consecutive patients. The cap was applied directly to the tip of the injured finger and allowed to separate gradually over the course of several weeks as new skin regenerated. This approach proved simple and effective in achieving a good functional and cosmetic result within a relatively short time, and eliminated the pain and discomfort associated with conventional dressing changes. We recommend the use of this dressing material in the Accident and Emergency department for the out-patient management of de-epithelializing fingertip injuries in both children and adults.

Adolescent↗
PubMed1998

Congenital skin loss following Nd:YAG placental photocoagulation.

This is the first reported case of congenital skin loss following endoscopic placental laser coagulation, a new technique for the ante-natal treatment of twin-twin transfusion syndrome. The skin defect healed rapidly after birth with dressings alone, mimicking the spontaneous re-epithelialisation of a minor burn wound or aplasia cutis congenita.

Burns↗
PubMed1998

A preliminary study of the use of peer support in smoking cessation programs for pregnant adolescents.

This article describes preliminary findings of an experimental, randomized, three-group, controlled design examining the effectiveness of a smoking cessation intervention for pregnant teens. The three groups are: Teen FreshStart with a buddy program (TFSB), a Teen FreshStart program (TFS) without peer support, and the Usual Care (UC) control group. Forty-six subjects completed the post-intervention assessment of smoking status. The TFSB group consistently achieved greater smoking cessation across all measures when compared to the subjects in the other two groups. These results indicate that the use of peer support may be an effective adjunct in smoking cessation programs for pregnant adolescents.

Adolescent↗
PubMed1997

A molecular approach to bone regeneration.

Bone morphogenetic proteins (BMPs) are becoming increasingly recognised as valuable molecular tools for regenerating bone and accelerating fracture healing. New bone growth is the result of BMP-induced differentiation of pluripotent mesenchymal cells along osteoblastic pathways. This phenomenon recapitulates in adults specific aspects of skeletal morphogenesis co-ordinated by BMPs during development. An understanding of the basic scientific research which has led to the characterisation and purification of these remarkable molecules is essential if their full therapeutic potential is to be realised.

Adult↗
PubMed1996

Vinylpyridine: an unusual cause of a chemical burn.

A case of a chemical burn following cutaneous exposure to vinylpyridine is presented. This unusual injury was distinguished by the delay in onset of pain and erythema, followed by gradual resolution leaving patchy skin discolouration. The properties of vinylpyridine are outlined. This case illustrates the dangers of long-term chemical storage and the importance of proper disposal.

Adult↗
PubMed1995

Surgical management of regional lymph nodes in primary cutaneous malignant melanoma.

The management of regional lymph nodes in the patient with primary cutaneous malignant melanoma remains a contentious issue. Early removal of nodes, which may harbour occult microscopic disease before the development of clinically detectable malignant lymphadenopathy, is thought by some to confer a survival advantage and/or improve locoregional tumour control. While tumour burden at lymphadenectomy has been shown to correlate with prognosis, there are conflicting reports regarding the efficacy of elective lymph node dissection (ELND) compared with a regimen of delayed therapeutic dissection for clinically detectable nodal involvement. Evaluation of arguments for and against ELND, together with consideration of surgical morbidity and the predictability of lymphatic drainage patterns, has allowed a clinical algorithm to emerge which may identify patients who may benefit from prophylactic surgery. A chronological summary of the relevant studies is presented and the overall division of opinion regarding the efficacy of ELND is discussed.

Head and Neck Neoplasms↗
PubMed1994

The conceptual basis for morpheme learning problems in children with specific language impairment.

Two groups of children were exposed to instances of a nonlinguistic conceptual rule under controlled instructional conditions to determine whether the problems children with specific language impairment (SLI) have learning and accessing language rules extend beyond the language domain into the general cognitive domain. The performance of 20 children with SLI, aged 5:0 to 6:11 (years:months), was compared to that of 20 normally developing children matched for age and nonverbal ability. These children were taught under two instructional conditions that differed only in whether the child was asked to imitate the solution to a conceptual problem after each demonstration (imitation) or merely to observe it (modeling). Contrary to previous findings regarding linguistic rule-learning using auditory or visual symbol systems and similar instructional conditions, no difference was found between the extent of overall learning displayed by the normally developing children and those with SLI. Also, the performance of the children with SLI was not uniquely better under the imitation condition than under modeling, as had been the case with the learning of a novel morpheme in an auditory linguistic task. These results are interpreted as confirming the earlier assumption that the generally lower overall learning rate of the children with SLI on both the auditory and visual tasks reflects a specific linguistic rule-learning difficulty, rather than a general deficiency in rule induction.

Child↗
PubMed1994

Indoor radon maps of the United States.

A recently published compilation of average radon levels in 1,729 U.S. counties with standard errors of approximately 20% is used to generate maps exhibiting these results and showing correlations over multicounty areas. Several large areas and numerous smaller areas with high radon levels are identified.

Air Pollution, Indoor↗
PubMed1993

Induction of a visual symbolic rule in children with specific language impairment.

In a design modeled after that of Connell and Stone (1992), two alternative instructional conditions (Modeling and Imitation) were used to teach a novel morpheme to a group of 21 children with Specific Language Impairment (SLI) (ages 5:0 to 6:11) and to 25 age- and ability-matched peers and 21 language-matched younger peers. In contrast to the use of the auditory modality in the Connell and Stone study, in the present study, the morphemes were embodied in a visual symbol system. The objects and meanings conveyed by the symbols were identical to those used in the earlier study. The present results indicated that both the children with SLI and their age-matched peers showed a benefit to their morpheme production from the requirement to imitate the use of the morpheme during learning trials. These results were interpreted as indicating that the group-specific benefit from imitation instruction on the part of the children with SLI found by Connell and Stone with their auditory task is unique to morpheme learning in the auditory modality. As in the earlier study, the children with SLI also tended to learn less than their age-matched peers in all conditions, indicating a possible general deficiency with symbolic rule induction.

Child↗