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991.
992.
Six normal and 16 neoplastic colorectal specimens were examined with 8.5-MHz ultrasound (US). An articulated system facilitated precise spatial correlation between US and histologic sections. Images were blindly interpreted and then compared with histologic results. All six normal specimen showed five distinct echo layers and were distinguished from neoplastic specimens by all the observers. The central echogenic layer, corresponding to the submucosa, is useful in determining the depth of origin of a neoplasm and the presence of submucosal invasion. US had an accuracy of 92.5% in demonstrating invasion of the submucosa and 77% for invasion of the muscularis externa. For mucosal neoplasms with invasion through the muscularis externa and extension into the subserosal tissues, nearly 90% of US interpretations were correct. High-frequency US may be useful in determining the depth of invasion of mucosal tumors with respect to the submucosa and in differentiating mucosal from extramural masses.  相似文献   
993.
Betaxolol hydrochloride, a selective beta:-adrenergic blocker, is claimed to be less likely to aggravate chronic obstructive airways disease than timolol maleate, a nonselective beta-blocker. It is not clear which drug is more effective in lowering intraocular pressure (IOP) and how each acts in combination with topical adrenaline. To assess this we conducted a randomised clinical trial on ocular hypertensive patients. Both betaxolol and timolol produced a significant fall in IOP though not in all patients. No significant difference was found between betaxolol and timolol. The addition of dipivefrin gave an additional fall in some eyes only. No significant difference was found between the addition of dipivefrin and adrenaline. Some fellow eyes had a fall in IOP when dipivefrin was added to timolol. It is important to assess the response carefully in each individual eye when using betaxolol or timolol or when adding additional medication.  相似文献   
994.
The case reports of 100 consecutive patients receiving aortic bifurcation grafts strictly for occlusive disease were reviewed. Fifty-seven diabetics and 43 nondiabetics constituted the study group. Mean age and preoperative risk factors were otherwise comparable. Sixty-eight percent of operations in diabetics were for limb salvage as compared with 47% in the nondiabetic group. All 100 patients survived the operation and left the hospital with open grafts. The complication rate was similar in both groups. Mean follow-up was 48 months in the diabetic group vs 58 months in the nondiabetic group. Thirty-three percent of the diabetics were dead at four years, a survival rate one half of that of the nondiabetics. Nine percent of patients in each group suffered late limb graft occlusions, a cumulative graft patency of 94% at five years. Limb loss and subsequent distal reconstruction were comparatively low although higher in the diabetic group. This suggests more and progressive distal arterial disease in the diabetics and not an unsuccessful inflow procedure. We conclude that aortic reconstruction can be safely carried out in diabetics with high graft patency and limb salvage rates.  相似文献   
995.
P.W. Keane  MD  FFARCS  FFARCSI    P.F. Murray  MB  BCh  BAO 《Anaesthesia》1986,41(6):635-637
The value of infusing a total of 2 litres of intravenous fluids intra- and postoperatively was assessed in 212 fasting patients undergoing minor surgery procedures. The treated patients (108) recovered from the effects of surgery and anaesthesia more quickly than patients without fluids (104). The results of improved quality of the postoperative recovery, a shorter hospital stay and earlier return to work, especially in those patients who had some difficulty in recovering from anaesthesia on previous occasions, encourages the more frequent use of intravenous fluids in minor surgery.  相似文献   
996.
SUMMARY The aim of this review is to sort out from the huge amount of facts related to digoxin in the literature those pertinent to current clinical practice. Seven aspects of digoxin are discussed: its mechanism of action, therapeutic controversy, clinical efficacy, avoidance of toxicity, manifestations of toxicity, indications, and its use in coronary artery disease  相似文献   
997.
998.
Purpose: The management protocol for herpetic stromal keratitis (HSK) is still controversial. We have attempted to compare the relative efficacy of topical dexamethasone 0.01 % and flurbiprofen 0.03% in combination with topical acyclovir 3% in HSK.
Methods: In this institutional, prospective, randomized, controlled, double-blind study, 45 clinically diagnosed cases of HSK were randomly distributed into three coded treatment groups — topical placebo, dexamethasone 0.01 %, and flurbiprofen 0.03% each in tapering frequency and in combination with acyclovir 3% ointment five times per day for four weeks. Therapeutic response was assessed every third day for four weeks. Decoding of the treatment groups was done at the conclusion of the study and data analysed.
Results: Four-week success rate was 93.3% (14 of 15) in the dexamethasone-acyclovir treatment group, 66.7% (10 of 15) in the flurbiprofen-acyclovir treatment group and 20% (3 of 15) in the placeboacyclovir treatment group.
Conclusion: While dexamethasone in combination with acyclovir gives the best results in HSK with minimal side-effects, the role of topical flurbiprofen seems promising.  相似文献   
999.
1000.
Thyrotoxicosis may exacerbate angina pectoris in patients with coronary artery disease but angina also occurs in thyrotoxic patients with normal coronary arteries. Four female severely thyrotoxic patients presented with apparent angina pectoris as a manifestation of their thyrotoxicosis. Two of them had transiently abnormal ECGs during pain. Treatment for thyrotoxicosis immediately stopped the chest pain, which did not recur. All patients had negative exercise ECGs, and one had a normal coronary angiogram. The possible mechanisms to explain this phenomenon are discussed. Coronary artery spasm has been demonstrated in thyrotoxic patients previously and may explain the features in these patients. An alternative hypothesis is that myocardial metabolism is fundamentally changed by thyrotoxicosis. We would recommend that thyroid function assessment should be considered in young female patients with atypical angina.  相似文献   
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