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1.
Objective An adequate lymph node harvest is necessary for accurate Dukes’ stage discrimination in colorectal cancer. The aim of this study is to identify the effect of variables, including the individual surgeon and pathologist, on lymph node harvest in a single institution. Method Three hundred and eighty one consecutive patients had resection for colorectal cancer, in a single unit. Factors influencing lymph node retrieval, including individual surgeon and reporting pathologist, were subjected to uni‐ and multivariate analysis. Actuarial survival of all patients with Dukes’ stage B and C disease was then calculated and survival compared between Dukes’ stage B and C at differing levels of lymph node harvest. Results The unit median lymph node harvest was 13 nodes/patient (95% CI 13.1–14.5). There was no difference in lymph node harvest between specialist colorectal surgeons and the pooled results of four nonspecialist consultant surgeons. However, there was a significant difference between reporting pathologists (P < 0.001). On univariate analysis, operation type, operative urgency, Dukes’ stage, T‐stage, reporting pathologist and use of neoadjuvant therapy in rectal cancer, were found to significantly affect lymph node retrieval. On multivariate analysis, operation type, T‐stage, reporting pathologist and neoadjuvant therapy in rectal cancer remained significant variables. Patients with one or more lymph node metastasis had greater nodal harvests than those without (median 15 vs 12 P = 0.02). Survival of patients with Dukes’ stage B disease was found to improve as lymph node harvest increased. Conclusion Overall lymph node harvest, in this unit, varied according to the reporting pathologist but not operating surgeon. As lymph node harvest increased to 15 per patient, the probability of identifying a metastatic node increased.  相似文献
2.
The accuracy of portable peak flow meters.   总被引:10,自引:10,他引:2       下载免费PDF全文
M R Miller  S A Dickinson    D J Hitchings 《Thorax》1992,47(11):904-909
BACKGROUND: The variability of peak expiratory flow (PEF) is now commonly used in the diagnosis and management of asthma. It is essential for PEF meters to have a linear response in order to obtain an unbiased measurement of PEF variability. As the accuracy and linearity of portable PEF meters have not been rigorously tested in recent years this aspect of their performance has been investigated. METHODS: The response of several portable PEF meters was tested with absolute standards of flow generated by a computer driven, servo controlled pump and their response was compared with that of a pneumotachograph. RESULTS: For each device tested the readings were highly repeatable to within the limits of accuracy with which the pointer position can be assessed by eye. The between instrument variation in reading for six identical devices expressed as a 95% confidence limit was, on average across the range of flows, +/- 8.5 l/min for the Mini-Wright, +/- 7.9 l/min for the Vitalograph, and +/- 6.4 l/min for the Ferraris. PEF meters based on the Wright meter all had similar error profiles with overreading of up to 80 l/min in the mid flow range from 300 to 500 l/min. This overreading was greatest for the Mini-Wright and Ferraris devices, and less so for the original Wright and Vitalograph meters. A Micro-Medical Turbine meter was accurate up to 400 l/min and then began to underread by up to 60 l/min at 720 l/min. For the low range devices the Vitalograph device was accurate to within 10 l/min up to 200 l/min, with the Mini-Wright overreading by up to 30 l/min above 150 l/min. CONCLUSION: Although the Mini-Wright, Ferraris, and Vitalograph meters gave remarkably repeatable results their error profiles for the full range meters will lead to important errors in recording PEF variability. This may lead to incorrect diagnosis and bias in implementing strategies of asthma treatment based on PEF measurement.  相似文献
3.
Role of primary cilia in the pathogenesis of polycystic kidney disease   总被引:8,自引:0,他引:8  
Cysts in the kidney are among the most common inherited human pathologies, and recent research has uncovered that a defect in cilia-mediated signaling activity is a key factor that leads to cyst formation. The cilium is a microtubule-based organelle that is found on most cells in the mammalian body. Multiple proteins whose functions are disrupted in cystic diseases have now been localized to the cilium or at the basal body at the base of the cilium. Current data indicate that the cilium can function as a mechanosensor to detect fluid flow through the lumen of renal tubules. Flow-mediated deflection of the cilia axoneme induces an increase in intracellular calcium and alters gene expression. Alternatively, a recent finding has revealed that the intraflagellar transport 88/polaris protein, which is required for cilia assembly, has an additional role in regulating cell-cycle progression independent of its function in ciliogenesis. Further research directed at understanding the relationship between the cilium, cell-cycle, and cilia-mediated mechanosensation and signaling activity will hopefully provide important insights into the mechanisms of renal cyst pathogenesis and lead to better approaches for therapeutic intervention.  相似文献
4.
5.
D C Weir  R I Gove  A S Robertson    P S Burge 《Thorax》1990,45(2):112-117
One hundred and twenty seven adults considered on clinical grounds to have non-asthmatic chronic airflow obstruction entered a randomised, double blind, placebo controlled, crossover trial comparing the physiological response to inhaled beclomethasone dipropionate 500 micrograms thrice daily with oral prednisolone 40 mg a day, both given for two weeks. One hundred and seven patients completed the study. Response was assessed as change in FEV1 and FVC measured on the last treatment day, and as change in mean peak expiratory flow (PEF) over the final seven days of treatment from home PEF recordings performed five times daily. A full response to treatment was defined as an increase in FEV or FVC, or an increase in mean daily PEF over the final seven days of treatment, of at least 20% from baseline values. An improvement in one measurement of at least 15%, or of 10% in any two measurements, was defined as a partial treatment response. Response to placebo showed a significant order effect, suggesting a carry over effect of active treatment of at least three weeks. Response to active treatment was therefore related to initial baseline values, and compared with placebo by considering responses in the first treatment phase only. A full response to oral prednisolone (16/38) was significantly more common than to placebo (3/35). The number of full responses to inhaled beclomethasone (8/34) did not differ significantly from the number responding to oral prednisolone or placebo in the first treatment phase, though full and partial responses to inhaled beclomethasone (12/34) were significantly more common than those to placebo (4/35). When all three treatment phases were considered 44/107 patients showed a full response to one or both forms of corticosteroid treatment, a response to prednisolone (39) occurring more frequently than to inhaled beclomethasone (26). Only 21 of the 44 responders showed a response to both forms of treatment. Inhaled beclomethasone dipropionate 500 micrograms thrice daily was inferior to oral prednisolone 40 mg per day, but better than placebo, in producing improvement in physiological measurements in patients thought to have nonasthmatic chronic airflow obstruction. It was, however, an effective alternative in over half of those showing a response to prednisolone.  相似文献
6.
A study was carried out to examine the independence from starting prebronchodilator FEV1 of four indices commonly used to express airflow (FEV1) reversibility in response to bronchodilators. In 121 patients with chronic airflow obstruction with a mean prebronchodilator FEV1 of 1.81 (43.9% of predicted values) the change in FEV1 expressed as a percentage of the patient's predicted FEV1 was the least dependent on starting FEV1. Reversibility, expressed as a percentage of the prebronchodilator value or as a percentage of the maximal possible increase (predicted minus starting FEV1) was correlated with starting FEV1.  相似文献
7.
G M Tsang  D C Watson 《Thorax》1992,47(1):3-5
BACKGROUND: The treatment and prognosis of non-small cell lung cancer, and assessment of the results of treatment, depend on accurate perioperative staging. The extent to which this is carried out in the United Kingdom is unknown. METHODS: A postal questionnaire survey was undertaken in 1990 to determine the perioperative staging practices of cardiothoracic surgeons in the United Kingdom. RESULTS: Replies from 77 surgeons, who between them performed about 4833 pulmonary resections a year for lung cancer, were analysed. Forty four per cent of surgeons, operating on 43% of the patients, do not perform computed tomography of the thorax or mediastinal exploration before surgery. They may therefore embark on a thoracotomy for stage III disease. At thoracotomy 45% of surgeons, operating on 40% of patients, do not sample macroscopically normal lymph nodes. They may therefore understage cases as N0/N1 when there is at least microscopic disease in mediastinal lymph nodes. CONCLUSIONS: The staging of lung cancer in the United Kingdom in 1990 appears in many instances to be inadequate. There should be a more organised approach to perioperative staging so that prognosis may be assessed and comparisons between groups of patients can be made.  相似文献
8.
Pediatric acute renal failure: outcome by modality and disease   总被引:5,自引:5,他引:5  
Two hundred and twenty-six children who underwent renal replacement therapy (RRT) from 1992 to 1998 were retrospectively reviewed. The mean age, at the onset of RRT, was 74±11.7 months and weight was 25.3±9.7 kg. RRT therapies included hemofiltration (HF; n=106 children for an average of 8.7±2.3 days), hemodialysis (HD; n=61 children for an average of 9.5±1.7 days), and peritoneal dialysis (PD; n=59 children for an average of 9.6±2.1 days). Factors influencing patient survival included: (1) low blood pressure (BP) at onset of RRT (33% survival with low BP, vs 61% with normal BP, vs 100% with high BP; P<0.05), (2) use of pressors anytime during RRT (35% survival in those on pressors vs 89% survival in those not requiring pressors; P<0.01), (3) diagnosis (primary renal failure with a high likelihood of survival vs secondary renal failure; P<0.05), (4) RRT modality (40% survival with HF, vs 49% survival with PD, vs 81% survival with HD; P<0.01 HD vs PD or HF), and (5) pressor use was significantly higher in children on HF (74%) vs HD (33%) or PD (81%; P<0.05 HD vs HF or PD). In conclusion, pressor use has the greatest prediction of survival, rather than RRT modality. Patient survival in children with the need for RRT for ARF is similar to in adults and, as in adults, is best predicted by the underlying diagnosis and hemodynamic stability. Received: 15 February 2001 / Revised: 5 June 2001 / Accepted: 8 August 2001  相似文献
9.
Background: T3N0 colon cancer is the target of many adjuvant studies. Very few studies have examined the relationship of the number of lymph nodes examined to the prognosis of this stage. We examined data from the National Cancer Data Base (NCDB) to determine whether the number of examined lymph nodes is prognostic for T3N0 colon cancer.Methods: A total of 35,787 prospectively collected cases of T3N0 colon cancer that were surgically treated and pathologically reported from 1985 to 1991 to the NCDB as T3N0M0 were analyzed.Results: The 5-year relative survival rate for T3N0M0 colon cancer varied from 64% if 1 or 2 lymph nodes were examined to 86% if >25 lymph nodes were examined. Three strata of lymph nodes (1–7, 8–12, and 13) distinguished significantly different observed 5-year survival rates.Conclusions: These results demonstrate that the prognosis of T3N0 colon cancer is dependent on the number of lymph nodes examined. A minimum of 13 lymph nodes should be examined to label a T3 colon cancer as node negative. These data suggest that adjuvant trials for T3N0 colon cancer should stratify according to the number of lymph nodes examined.Presented at the 54th Annual Meeting of the Society of Surgical Oncology, Washington, DC, March 17, 2001  相似文献
10.
Anatomy of the falcine venous plexus   总被引:5,自引:0,他引:5  
OBJECT: The superior and inferior sagittal sinuses have been well studied. Interestingly, other venous structures within the falx cerebri have received scant attention in the medical literature. The present study was performed to elucidate the presence and anatomy of these midline structures. METHODS: The authors examined 27 adult latex- or ink-injected cadaveric specimens to observe the morphological features of the sinuses within the falx cerebri (excluding the inferior and superior sagittal sinuses). RESULTS: All specimens were found to have an extensive network of small tributaries within the falx cerebri that were primarily concentrated in its posterior one third. In this posterior segment, these structures were usually more pronounced in the inferior two thirds. The portion of the falx cerebri not containing significant falcine venous sinus was termed a "safe area." These vascular channels ranged in size from 0.5 mm to 1.1 cm (mean 0.6 mm); 100% of these vessels communicated with the inferior sagittal sinus. Classification of the structures was then performed based on communication of the falcine venous sinus with the superior sagittal sinus. Type I falcine sinuses had no communication with the superior sagittal sinus, Type II falcine sinuses had limited communication with the superior sagittal sinus, and Type III falcine sinuses had significant communication with the superior sagittal sinus. Seventeen (63%) of 27 specimens communicated with the superior sagittal sinus (Types II and III). Further subdivision revealed 10 Type I, seven Type II, and 10 Type III falcine venous plexuses. CONCLUSIONS: There are other venous sinuses in the falx cerebri in addition to the superior and inferior sagittal sinuses. Neurosurgical procedures that necessitate incising or puncturing the falx cerebri can be done more safely via a described safe area. Given that the majority of specimens in the authors' study were found to have a plexiform venous morphology within the falx cerebri, they propose that these channels be referred to as the falcine venous plexus and not sinus. The falcine venous plexus should be taken into consideration by the neurosurgeon.  相似文献
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