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91.
92.
To define the indications for elective neck treatment, the cases of 474 previously untreated patients were reviewed who had locally confined major salivary gland cancers treated between 1939 and 1982. Clinically positive nodes were present in 14% (67 of 474). Overall, clinically occult, pathologically positive nodes occurred in 12% (47 of 407). By univariate analysis, several factors appeared to predict the risk of occult metastases; however, multivariate analysis revealed that only size and grade were significant risk factors. Tumors 4 cm or more in size had a 20% (32 of 164) risk of occult metastases compared with a 4% (nine of 220) risk for smaller tumors (P less than 0.00001). High-grade tumors (regardless of histologic type) had a 49% (29 of 59) risk of occult metastases compared with a 7% (15 of 221) risk for intermediate-grade or low-grade tumors (P less than 0.00001). In view of the low frequency of occult metastases in the entire group, routine elective treatment of the neck is not recommended. High-grade tumors and larger tumors have a high rate of occult neck metastases, and treatment should be considered in this group.  相似文献   
93.
A survey by questionnaire was carried out to examine the level of nursing staff satisfaction with the acute psychiatric services. Comparisons were made between views of older psychiatric hospitals and newer district general hospital units, and before and after the closure of Friern Barnet Hospital, London, England when the service was reorganized to include fewer beds. The importance of nurses having their say is emphasized, and areas in which improvements can be made are suggested.  相似文献   
94.
OBJECTIVE: The purpose is to define factors influencing long-term patency of the internal thoracic artery (ITA) to optimize the operative strategy. METHODS: 1482 left internal thoracic artery (LITA) and 636 right internal thoracic artery (RITA) symptom-directed angiograms were studied in 1434 patients. Data were prospectively collected from patients who had primary coronary artery bypass surgery during the period 1982-2002. The mean age of patients was 59 years; 85% were male. The mean period from operation to re-angiogram was 80 months. LITA was grafted to left anterior descending coronary artery (LAD) in 82% of cases, RITA to right coronary artery (RCA) in 40% and circumflex artery in 35% of cases. Graft failure was defined as > or =80% stenosis. RESULTS: 96.3% of LITA and 88.1% of RITA grafts were patent. No patient variables were significantly associated with graft patency (age, gender, diabetes, hypertension, LVEF, NYHA, AMI). Target coronary artery was associated with patency of both LITA and RITA grafts with maximum patency when grafted to LAD (P = 0.02) RITA had the worst patency to RCA, patency for the left system was identical to LITA. Proximal anastomosis to aorta (free RITA) had significantly better patency when compared with in situ RITA to RCA system (P = 0.005) while similar patency when grafted to left system. ITA diameter and target artery diameter were not associated with graft patency. Recent operations had better RITA patency (P = 0.03). The interval from operation to angiogram was not associated with ITA patency (96% patency for LITA and 88% patency for RITA, remained stable when studied at <1, 1-4, 5-9, 10-14 and >15 years). CONCLUSIONS: Even in a patient cohort that had adverse symptoms, excellent LITA and RITA patency was achieved which almost remained constant through all time intervals studied.  相似文献   
95.
Physicians who treat multiple sclerosis (MS) face the challenge of patients exhibiting ongoing disease activity, including exacerbations, loss of functional capabilities, intellectual decline, and radiologic progression, despite being on a disease-modifying agent (DMA). After searching for factors that might at least in part explain these changes—such as nonadherent drug-taking behavior, or the presence of interfer-on-neutralizing antibodies—some providers may ultimately decide to switch the patient to another DMA. In most circumstances, patients likely derive only partial effects from these agents, even in the absence of compromising factors. Thus, a number of factors must be considered in order to intensify the treatment regimen in response to disease progression. In the context of an inadequate treatment response to a DMA, some clinicians will convert the patient to an alternative therapy, and others will instead use a second agent in combination with the first (the so-called platform agent). In the first of this two-part series, we explored the use of anti-inflammatory CS and ACTH to treat MS exacerbations. Although we underscored the limited availability of evidence-based studies to support specific regimens for this purpose, there is an even greater paucity of data to support the routine use of these agents in order to achieve chronic disease-modifying effects in those who continue to deteriorate clinically, radiographically, or both. Without doubt, a number of factors influence the formulation of combination treatment plan for MS. Nevertheless, we will focus on the rationale and practical schemes that can be considered for using corticosteroids (CS) (and perhaps even ACTH) in an attempt to modify various domains of ongoing disease activity.  相似文献   
96.
Mary A. Moxon  MB  ChB  FFARCS    M.E. Ward  MB  BS  FFARCS 《Anaesthesia》1986,41(5):543-546
An operating theatre fire and the steps taken to deal with it are described; the difficulties encountered in evacuating anaesthetised patients are highlighted. Measures which might be taken to prevent recurrence of these problems, and recommendations on the institution of fire drills for the safety of patients and staff are given.  相似文献   
97.
Despite the current popularity of binocular indirect ophthalmoscopy, direct ophthalmoscopes are still commonly used by clinicians for fundus examination. They are considered to be expensive, however, and it has been suggested that this cost can prevent their use by healthcare professionals in developing countries. The Optyse Lens Free Ophthalmoscope is a novel direct ophthalmoscope, without a lens focus system, that allows for comparatively inexpensive manufacture and supply. We compared the clarity of view with the Optyse to that with standard direct ophthalmoscopes, over a sequential cohort of patients with a variety of refractive errors and ocular conditions. The grade of clarity of view with the Optyse Lens Free Ophthalmoscope was less than conventional ophthalmoscopes (Wilcoxon signed rank test, p < 0.0001). This grade of clarity of view was not associated with the ametropia of the ophthalmoscopic observation (Spearman r < or = 0.03, p > or = 0.28) but was with the presence of cataracts (chi2 test, p < 0.0001) with both the Optyse and the conventional ophthalmoscopes. Despite its limitations, the retinal view with Optyse was often within acceptable clinical limits suggesting that this relatively inexpensive ophthalmoscope may have a place when cost prohibits any other type of ophthalmoscope use.  相似文献   
98.
The effects of the calcium antagonists verapamil and nifedipine on blood glucose levels, glucose tolerance, insulin secretion during glucose tolerance and hypoglycaemic effect of tolbutamide were studied in normal nondiabetic rabbits. Daily dosage of 40 mg/kg verapamil and 5 mg/kg nifedipine given orally up to 7 days did not affect blood glucose level, glucose tolerance, insulin secretion during glucose tolerance and hypoglycaemic activity of tolbutamide 250 mg/kg p.o.  相似文献   
99.
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease.  相似文献   
100.
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