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Over a two-year period about 1,000 operations were performed with cardiopulmonary bypass. Intraaortic balloon pump assistance (IABP) was employed on 150 occasions, and a review of these has permitted clarification of the indications for its use. Sixty patients had IABP for carcinogenic shock either after infarction or cardiotomy, and 37 (62%) survived. Preoperative IABP in 90 high-risk patients resulted in survival for 79 (88%). The indications for prophylactic IABP included: (1) relief of severe pain, which occurred in 42 patients with acute coronary insufficiency, (2) improvement in the coronary perfusion pressure, which was accomplished in 20 patients with significant left main coronary artery occlusion or its equivalent, and (3) protection of left ventricular function, which war carried out in 28 patients with an LV ejection fraction of less than 0.40. The significance of the preoperative endocardial viability ratio (EVR) in relation to prophylactic IABP was also assessed: an EVR below 0.70 appears to be an indication for preoperative IABP.  相似文献   
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A study was made of the routine electronic measurements of erythrocyte size and hemoglobin concentration in blood samples from 122 patients with decreased transferrin saturation and 66 patients with elevated levels of hemoglobin A2 or F. The medical histories of these patients were reviewed to identify 52 cases of uncomplicated iron-deficiency anemia and 39 cases of uncomplicated thalassemia minor. Four decision functions were compared for separating these two disorders. The functions evaluated were: D.F'. = MCV--[5 X Hb]-RBC; ratio MCV/RBC; ratio MCH/RBC, and RBC. The rules performed better in the uncomplicated cases than in the routine laboratory defined cases. Only minor differences in the performances of the various decision functions were observed. None was sufficiently accurate for final diagnosis, but they should have value in screening patients and in determining which additional test should be considered.  相似文献   
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PURPOSE: To determine the accuracy of applanation tonometry in patients with corneas thinned by photorefractive keratectomy, and to correlate corneal changes with tonometric readings. METHODS: The intraocular pressure was measured with Goldmann applanation tonometry in 87 patients who underwent photorefractive keratectomy before and 1, 6 and 12 months after treatment. The treatments ranged from -1.5 to -14 diopters (mean=-7.6+/-4.1 diopters) and the fellow eyes were used as controls. RESULTS: In the treated eyes the intraocular pressure before surgery ranged from 11 to 26 mmHg (mean=17.7+/-2.8 mmHg). One month after surgery it ranged from 5 to 22 mmHg (mean=11.9+/-2.7 mmHg) with a significant underestimation (P=1x10(-33)). Six months after surgery it ranged from 6 to 22 mmHg (mean=12+/-3 mmHg) with a significant underestimation (P=5x10(-30)). Twelve months after surgery it ranged from 8 to 22 mmHg (mean=12.7+/-2.7 mmHg) with a significant underestimation (P=5x10(-31)). CONCLUSIONS: A correcting factor should be applied when using applanation tonometry to measure intraocular pressure in patients who have undergone PRK.  相似文献   
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Gloves should provide two-way protection from the transmission of microorganisms between worker and patient. Until recently, glove manufacturers paid little attention to barrier properties. Because the operating room is a high-risk area, surgical nurses must be especially careful about gloving practices.  相似文献   
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OBJECTIVES: Although no generally effective treatment for proctalgia fugax is known, inhalation of salbutamol has been reported to shorten pain attacks in isolated cases. METHODS: We conducted a randomized, double-blind, placebo-controlled, crossover trial of inhaled salbutamol in 18 patients with proctalgia fugax. The clinical effect was evaluated by recording the duration of severe pain and discomfort during acute attacks. In addition, anorectal motility recordings were analyzed for possible changes in anal resting tone, sphincter relaxation during rectal distension and in rectal compliance prior to and following administration of the two test substances. RESULTS: Sixteen patients completed all investigations. Compared to placebo, salbutamol inhalation shortened the duration of severe pain (p = 0.019). The effect was most marked in patients having prolonged attacks. In the asymptomatic state, neither salbutamol nor placebo led to a significant change in anal resting pressure, anal relaxation during rectal distension, or rectal compliance. Salbutamol also did not alter the threshold for rectal sensation. CONCLUSIONS: Salbutamol inhalation shortens attacks of severe pain in patients with proctalgia fugax. The mechanism of this effect remains unexplained.  相似文献   
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