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排序方式: 共有969条查询结果,搜索用时 672 毫秒
91.
BF O'Donnell JR Marsden CA O'Donnell DS Sanders C Billingham 《Canadian Metallurgical Quarterly》1996,34(4):632-637
BACKGROUND: Relatively few studies have addressed the question of whether clinical estimation of melanoma thickness by palpation can accurately predict its histologic thickness. If palpability was a reliable predictor of dermal invasion, it could be used to define the surgical margin. OBJECTIVE: We sought to determine whether clinical elevation of melanoma could be used to predict the presence or absence and the degree of dermal invasion in patients with stage 1 cutaneous melanoma. METHODS: Melanomas in 165 patients were categorized by one observer as flat, just palpable, palpable, or nodular. This was compared with histologic measurements of tumor thickness. RESULTS: Overall there was significant correlation between the degree of palpability of melanoma and the presence or absence of dermal invasion (p<0.001), Breslow thickness (p<0.0001), and Clark level (p<0.001). However, the relation between palpability and Breslow thickness for invasive melanomas less than 1 mm thick was weaker (n=62, p=0.053), and the correlation between elevation and Clark level was not significant for invasive melanomas less than 4 mm thick (n=111, p>0.999). CONCLUSION: We conclude that palpability of melanoma is an inadequate guide to the presence or absence and degree of dermal invasion in melanomas less than 1 mm thick and cannot be used to determine the surgical margin. 相似文献
92.
HB Peterson 《Canadian Metallurgical Quarterly》1998,279(20):1651-1658
93.
A Schrag Y Ben-Shlomo R Brown CD Marsden N Quinn 《Canadian Metallurgical Quarterly》1998,13(6):885-894
The authors report on clinical features and mortality rates in a group of 149 patients with apparent idiopathic parkinsonism starting before the age of 40 years. Ten had juvenile parkinsonism (JP; onset before age 21 years) and 139 had young-onset Parkinson's disease (YOPD; onset at age 21 to 40 years). Included were 60 patients originally reported 10 years ago. Fifty percent of the JP group had a positive family history of parkinsonism in a first-degree relative, and clinical presentation was heterogeneous. Mortality risk was threefold that of the normal population. In the YOPD group, the mortality risk was double that of the normal population. Poor initial response to L-dopa was a risk factor for early death. In two previously reported patients, the diagnosis had been changed to multiple system atrophy and Machado-Joseph disease. After a median disease duration of 18 years, cognitive impairment was found in only 19% of YOPD patients (13% of those younger than 60 years and 43% of those 60 years or older). Age was the most important factor for development of dementia, but female sex and positive family history of parkinsonism also had more modest predictive value. After a disease duration of 10 years or less, only 5% of patients were experiencing falls and 30% freezing, but all patients had developed L-dopa-related fluctuations and dyskinesias. The authors conclude that the mortality rate in parkinsonism starting before the age of 40 is increased in comparison to the normal population and is similar to the general Parkinson's disease population. Intellectual function and postural reflexes are usually well preserved for many years despite a long history of parkinsonism and the early and frequent occurrence of treatment complications, provided the patients remain biologically and chronologically young. 相似文献
94.
The results of 26 ankle arthrodeses performed for rheumatoid arthritis on 21 patients were reviewed. Tibiotalar arthrodesis was performed in 14 ankles, and tibiotalocalcaneal arthrodesis was performed in 12. External fixation was used in 20 ankles, and internal fixation was used in six. Followup was available in 24 of 26 ankles (19 patients), and averaged 5 years (range, 2-8 years). There was no pain experienced in 19 ankles; mild, occasional pain was experienced in four ankles; and moderate, daily pain was experienced in one ankle. Daily activities were limited in five patients and recreational activities were limited in 11. All patients reported some difficulty walking on uneven terrain. Nearly all patients were satisfied; two were satisfied with reservations and two were dissatisfied. Union was achieved in 25 of 26 (96%) ankles. Ankle arthrodesis is an effective operation in patients with rheumatoid arthritis. Unlike previous reports, union and complication rates in this series were comparable with rates for arthrodesis for posttraumatic and degenerative arthritis. 相似文献
95.
IM Robbins LL Cuiper CM Stein AJ Wood HB He R Parker BW Christman 《Canadian Metallurgical Quarterly》1998,85(2):731-737
Prostacyclin (or epoprostenol), an arachidonic acid metabolite, is an effective treatment for patients with primary pulmonary hypertension. Interruption of chronic prostacyclin infusion can result in recurrent symptoms of dyspnea and fatigue. The etiology of this phenomenon is unknown. We hypothesized that sympathoadrenal activation could lead to increased vascular tone after abrupt termination of the infusion. To evaluate this effect, we monitored six chronically instrumented, awake sheep during and after infusion of prostacyclin. Prostacyclin decreased mean arterial pressure (MAP) by 14% and increased cardiac output by 33%. After the infusion ceased, MAP rebounded 23% above baseline, and cardiac output decreased by 28% from peak values within 10 min. We were unable to demonstrate an increase in norepinephrine levels after cessation of prostacyclin, nor did alpha-adrenergic blockade affect postinfusion hemodynamics. However, plasma renin activity increased >10-fold at peak infusion and remained elevated for up to 2 h after discontinuation of prostacyclin. Coinfusion of the angiotensin II-receptor antagonist L-158,809 resulted in complete abrogation of the postcessation rise in MAP. We conclude that renin-angiotensin system activation is primarily responsible for systemic hypertension occurring after abrupt cessation of prostacyclin infusion in sheep and that angiotensin II receptor blockade prevents this response. Our data do not support a role for sympathetic nervous system activation in the systemic pressor response after prostacyclin infusion. 相似文献
96.
F Santos J Campos J Freire A Andrade I Távora HB Castelo 《Canadian Metallurgical Quarterly》1997,44(16):1085-1089
Enterocutaneous fistulas are not a minor problem in gastrointestinal tract surgery. Significant reduction of mortality and morbidity has been attained but they still remain high. The authors report three clinical cases in which they sealed and treated enterocutaneous, chronic, iatrogenic fistulas by injecting biological glue (N-Butil 2-Cyanoacrylate-Histoacryl) into the internal opening and fistulous tract. We believe that the technic we propose here, in the proper setting, may be an important contribution to the management of iatrogenic (postoperative) enterocutaneous fistulas. 相似文献
97.
T Stokke H Holte L Smedshammer EB Smeland O Kaalhus HB Steen 《Canadian Metallurgical Quarterly》1998,77(11):1832-1838
We have examined apoptosis and proliferation in lymph node cell suspensions from patients with B-cell non-Hodgkin's lymphoma using flow cytometry. A method was developed which allowed estimation of the fractions of apoptotic cells and cells in the S-phase of the cell cycle simultaneously with tumour-characteristic light chain expression. Analysis of the tumour S-phase fraction and the tumour apoptotic fraction in lymph node cell suspensions from 95 B-cell non-Hodgkin's lymphoma (NHL) patients revealed a non-normal distribution for both parameters. The median fraction of apoptotic tumour cells was 1.1% (25 percentiles 0.5%, 2.7%). In the same samples, the median fraction of apoptotic normal cells was higher than for the tumour cells (1.9%; 25 percentiles 0.7%, 4.0%; P = 0.03). The median fraction of tumour cells in S-phase was 1.4% (25 percentiles 0.8%, 4.8%), the median fraction of normal cells in S-phase was significantly lower than for the tumour cells (1.0%; 25 percentiles 0.6%, 1.9%; P = 0.004). When the number of cases was plotted against the logarithm of the S-phase fraction of the tumour cells, a distribution with two Gaussian peaks was needed to fit the data. One peak was centred around an S-phase fraction of 0.9%; the other was centred around 7%. These peaks were separated by a valley at approximately 3%, indicating that the S-phase fraction in NHL can be classified as 'low' (< 3%) or 'high' (> 3%), independent of the median S-phase fraction. The apoptotic fractions were log-normally distributed. The median apoptotic fraction was higher (1.5%) in the 'high' S-phase group than in the 'low' S-phase group (0.8%; P = 0.02). However, there was no significant correlation between the two parameters (P > 0.05). 相似文献
98.
The clinical features and family histories of 20 adults with dyskinetic cerebral palsy from 20 families were studied. The majority of the patients showed progressive neurological deterioration in adult life. In only three did the condition stabilise by 10 years of age and in seven there was deterioration after the age of 30. Two patients developed a secondary cervical spondylotic myelopathy. Four patients had affected relatives and there were similar proportions of affected parents and siblings. The family data suggest genetic heterogeneity with autosomal recessive and dominant variants. The existence of an X-linked form cannot be excluded, and the demonstration of an increased paternal age effect among single cases suggests that some of these may arise because of fresh dominant genetic mutation. 相似文献
99.
BH Brummett MA Babyak JC Barefoot HB Bosworth NE Clapp-Channing IC Siegler RB Williams DB Mark 《Canadian Metallurgical Quarterly》1998,60(6):707-713
OBJECTIVE: Hospitalization for cardiac disease is associated with an increased risk for depression, which itself confers a poorer prognosis. Few prospective studies have examined the determinants of depression after hospitalization in cardiac patients, and even fewer have examined depression within the weeks after hospital discharge. The present study assessed the prospective relations among perceptions of social support and trait hostility in predicting symptoms of depressive symptoms at 1 month after hospitalization for a diagnostic angiography in 506 coronary artery disease (CAD) patients. METHOD: A series of structural equation models 1) estimated the predictive relations of social support, hostility, and depressive symptoms while in the hospital to symptoms of depression 1 month after hospitalization, and 2) compared these relations across gender, predicted risk classification, and age. RESULTS: Social support assessed during hospitalization was independently negatively associated with depressive symptoms 1 month after hospitalization, after controlling for baseline symptoms of depression, gender, disease severity, and age. Hostility was an indirect predictor of postdischarge depressive symptomology by way of its negative relation with social support. This pattern of relations did not differ across gender, predicted risk classification, and age. CONCLUSIONS: Our findings suggest that a patient's perceived social support during hospitalization is a determinant of depressive symptoms 1 month later. The relation of social support and hostility to subsequent depressive symptoms was similar across a variety of populations. 相似文献
100.
Patients with COLD may develop Mg depletion due to inadequate nutrition or treatment with diuretics and beta 2-agonists. In 36 consecutive COLD patients skeletal muscle concentrations of Mg and K were reduced by 22% and 14%, respectively, compared to 23 age- and sex-matched controls (p < 0.001). Patients receiving diuretics showed a further reduction of muscle Mg (-31%) and K (-27%) compared to controls. The mean concentration of Na,K pumps was increased by 31% (p < 0.001), while a more pronounced increase (+61%) was seen in 12 intensive care patients receiving high dosages of glucocorticoids. Thus muscle concentrations of Mg and K are reduced in COLD patients and are associated with an upregulation of the Na,K-pump concentration. It is plausible that this upregulation may be caused by glucocorticoid treatment. The clinical benefits of glucocorticoids may therefore in part be due to an increased activity and capacity of the Na,K-pump and thereby in a possible enhancement of muscle force. 相似文献