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91.
目的为探讨老年人肺癌院内获得性肺炎的临床特点、病原菌及耐药情况,为临床提供依据。方法分析72例老年人肺癌并发院内获得性肺炎的临床资料。结果老年人肺癌平均住院日期延长,化疗时不合理使用抗菌药物,发生院内获得性肺炎的机会最大。主要病原菌为G~-杆菌占80.70%,其中以铜绿假单胞菌、肺炎克雷伯氏菌为主,其次为表皮葡萄球菌占10.53%。病原菌对氨苄青霉素、哌拉西林、头孢菌素耐药性增加,对亚胺培南、万古霉素、阿米卡星敏感。病死率达30.56%。结论老年人肺癌免疫功能低下,住院日期延长,不合理使用抗生素是造成院内感染的主要因素。病原菌的耐药率呈增加趋势,病死率较高。  相似文献   
92.
Whether total surgical correction of tetralogy of Fallot in adults aged 40 years old or older has acceptable operative risk and gratifying long-term results is unknown. The Mayo Clinic experience (June 1960 to May 1982) with 30 patients 40 to 60 years old (mean 47) who had total surgical correction of tetralogy of Fallot was reviewed. Preoperatively, 4 patients (13%) were in functional class I, 9 (30%) in class II and 17 (57%) in classes III and IV. Eight patients (27%) had had preoperative complications: five had a cerebrovascular accident and three had infective endocarditis. Only 11 patients (37%) had had palliative surgery 16 to 34 years (mean 22) before total surgical correction. Total surgical correction was successful in all patients. Right ventricular to left ventricular (RV/LV) pressure ratio of 0.65 or less was achieved in 28 (93%) of the 30 patients. One patient died of ventricular fibrillation (RV/LV ratio = 0.8) 2 days postoperatively, one had complete heart block and one had a cerebrovascular accident 7 days after operation. At follow-up of 5 to 266 months (mean 110), there were seven late deaths: two sudden at 5 and 21 years, respectively, after operation, one from myocardial infarction at 11 years, one from cerebrovascular accident at 11 years, one from congestive heart failure (RV/LV ratio = 1.0) at 8 years and two from noncardiac causes. Of the 22 patients who survived, 16 are in class I, 5 are in class II and 1 is in class III.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
93.
Between 1979 and 1983, 50 patients were treated by endoscopic sphincterotomy for disabling biliary-type pain after cholecystectomy. Forty-six patients were seen at regular intervals for at least 12 months after the procedure and of these, pain resolved in six (13%), decreased in severity and/or frequency in 22 (48%), and continued unchanged in 18 (39%). Patients with bile duct dilation on a retrograde cholangiogram had a similar outcome to those with a bile duct of normal caliber. Twenty-five patients had a morphine-neostigmine test and endoscopic manometry of the sphincter of Oddi prior to the procedure, and the outcome appeared to be independent of results from these investigations. Subgroups of patients who benefit from sphincterotomy will be determined only by prospective studies in which criteria for inclusion are carefully defined so as to avoid heterogeneity within study groups.  相似文献   
94.
To evaluate functional recovery in 20 consecutive patients with acute myocardial infarction who received recombinant tissue-type plasminogen activator, serial two-dimensional echocardiograms were performed before and immediately after tissue plasminogen activator administration and at 1 and 10 days postinfarction. Tissue plasminogen activator was administered intravenously (17 patients) or by intracoronary infusion (3 patients) after angiographic confirmation of total occlusion. Reperfusion, documented by angiography, occurred in 13 of the 20 patients. The mean time from onset of chest pain to thrombolysis was 5.1 +/- 1.1 hours. Echocardiograms were evaluated for regional function with a visual semiquantitative scoring system by two independent observers who had no knowledge of patient identity, temporal sequence, therapy or effect of therapy. There was no immediate or 24 hour improvement in wall motion. At day 10 compared with pretreatment, 28 of 33 reperfused infarct zone segments versus 6 of 20 nonreperfused infarct segments demonstrated improved wall motion (p = 0.01). This improvement did not relate to time from onset of chest pain to successful thrombolysis. Of reperfused infarct zone segments in the distribution of coronary artery balloon dilation, 19 of 23 segments exhibited improvement versus 7 of 17 (reperfused, no angioplasty) and 6 of 20 (nonreperfused, no angioplasty) segments (p = 0.001). Infarct zone segments reperfused at the time of ongoing chest pain demonstrated functional recovery compared with segments reperfused in the absence of chest pain (18 of 23 versus 10 of 20, respectively; p = 0.05). Thus, in this uncontrolled series, there was echocardiographically detectable improvement in function of reperfused infarct segments 10 days after coronary thrombolysis with recombinant tissue plasminogen activator.  相似文献   
95.
Transient hypoxemia is not uncommon after major cardiac or thoracic surgery. The differential diagnosis includes atelectasis, pulmonary embolus, pneumonitis, congestive heart failure and several other diverse cardiovascular and pulmonary problems. Less well recognized is transient right to left intracardiac shunting through a patient foramen ovale or previously unsuspected atrial septal defect. Three cases of clinically important hypoxemia associated with right to left shunting after aortocoronary bypass surgery are presented. The right to left shunting was documented with contrast-enhanced echocardiography, which is a simple, inexpensive and accurate means of screening patients for intracardiac right to left shunts and may play a valuable role in the postoperative management of patients.  相似文献   
96.
Methicillin-resistant Staphylococcus aureus (MRSA) has become endemic in Detroit, accounting for 50% of bacteremias in heroin abusers. To identify the salient epidemiologic and clinical features of MRSA bacteremia, case-control studies were performed comparing 28 cases of MRSA bacteremia to 28 cases of methicillin-sensitive S. aureus (MSSA) bacteremia in intravenous drug abusers. Infective endocarditis was diagnosed in 46.4% (13 of 28). In endocarditis and nonendocarditis bacteremia alike, the duration of fever, length of hospitalization, need for surgery, and mortality rates were similar. A history of recent antimicrobial therapy, especially cephalosporins, was more common in the MRSA group (p = 0.006). Complications including neurologic, renal, vascular, and musculoskeletal manifestations were more common in the MSSA endocarditis patients than MRSA endocarditis patients, although this difference was not significant. Complications related to antibiotic therapy were similar for both groups. The case-control studies indicate that MRSA and MSSA are similar in their virulence as measured by duration of hospitalization, duration of fever, complications, and mortality.  相似文献   
97.
The maximal aerobic exercise capacity of patients with chronic heart failure is frequently decreased because of inadequate blood flow to working skeletal muscle. To investigate whether this reduced flow is in part due to interference by angiotensin II with arteriolar dilation in working muscle, the effect of the angiotensin-converting enzyme inhibitor captopril on leg blood flow, leg vascular resistance, leg oxygen consumption (VO2) and leg lactate release during maximal upright bicycle exercise was examined in 12 patients with heart failure (maximal VO2 10.7 +/- 3.1 ml/min per kg). Captopril decreased leg resistance at rest (258 +/- 115 to 173 +/- 67 U, p less than 0.01) and maximal exercise (68 +/- 69 to 45 +/- 29 U, p less than 0.01) associated with proportionately similar decreases in systemic vascular resistance. However, maximal exercise duration and maximal VO2 were unchanged and, at identical peak exercise work times, there was no improvement in leg blood flow (2.0 +/- 0.9 to 2.0 +/- 1.1 liters/min, p = NS), leg VO2 (261 +/- 104 to 281 +/- 157 ml/min, p = NS) or leg lactate release (269 +/- 149 to 227 +/- 151 mg/min, p = NS). These data suggest that, during exercise in patients with heart failure, angiotensin II does not interfere with blood flow to working skeletal muscle.  相似文献   
98.
MDL 17,043, an inotropic and vasodilator drug, is believed to have beneficial effects in patients with heart failure. Its short- and long-term hemodynamic and cardiopulmonary effects were studied in 10 patients with New York Heart Association functional class III heart failure who were maintained on digitalis and diuretic drugs. Hemodynamics at baseline study and after 24 hours of oral therapy (four doses of 6 mg/kg) showed increased cardiac output (3.9 +/- 0.7 to 6.1 +/- 1.1 liters/min, p less than 0.05), increased stroke volume (42 +/- 12 to 60 +/- 15 ml, p less than 0.05), decreased systemic vascular resistance (1,564 +/- 326 to 1,009 +/- 296 dynes X s X cm-5, p less than 0.05) but no change in pulmonary capillary wedge pressure (31 +/- 6 to 25 +/- 13 mm Hg, p = NS). Only systemic vascular resistance and arteriovenous oxygen difference were significantly decreased during exercise. When restudied after 5 weeks of therapy, neither cardiac output nor stroke volume showed a sustained increase at rest or during exercise, and effects on systemic vascular resistance and arteriovenous oxygen difference were not sustained at exercise (p = NS). Peak oxygen uptake during exercise was 8.1 +/- 2.5 ml/kg per min at baseline and was not significantly increased either acutely (9.2 +/- 2.4 ml/kg per min, p = NS) or chronically (8.9 +/- 2.2 ml/kg per min, p = NS). Problems of increased ventricular arrhythmias and diarrhea were noted after therapy was begun.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
99.
Exercise-induced changes in the ST segments of the electrocardiogram were compared with the results of coronary arteriography in 73 consecutive patients referred for preoperative evaluation of coronary artery disease. Eighteen patients had single-, 25 double-, and 30 triple-vessel disease. Thirteen were taking digitalis alone, 28 were taking beta blockers alone, 21 had beta blockers and digitalis and 11 had no cardiac drugs. Exercise induced elevation of the ST segment in 11 patients, all with a predominant lesion in the left anterior descending coronary artery. ST depression with an upsloping ST segment was observed in patients with one-, two-, and three-vessel disease and it was the most common type of ST change in patients with single-vessel disease. Horizontal ST depression was most common in two-vessel disease and downsloping ST segment in three-vessel disease. There was a good correlation between the number of stenosed vessels and ST changes caused by exercise, expressed as the sum of ST segment displacements in twelve leads recorded immediately after the end of exercise (sigma/ST/) or as ST depression per unit increase in heart rate during exercise ("m" (ST/HR]. The latter was obtained by linear regression of ST displacement and heart rate measured at three or four different workloads in the lead with the greatest displacement of the ST segment. The mean values of sigma/ST/ were 0.58 +- 0.030 mV in single-vessel, 0.97 +- 0.41 mV in double-vessel and 1.58 +- 0. 46 mV in triple-vessel disease. The mean values of "m" (ST/HR) were 0.0024 +- 0.0013 mV X min-1 X beat-1 in single-vessel, 0.0042 +- 0.0012 in double-vessel, and 0.0078 +- 0.0033 in triple-vessel disease. These differences were highly significant (p less than 0.01 - 0.001) and there was only minimal overlap between the single- and triple-vessel groups. Digitalis caused a slight (statistically nonsignificant) increase in sigma/ST/ but not in "m" (ST/HR).  相似文献   
100.
The serologic and viral profiles of 24 patients who presented with acute hepatitis B virus (HBV) infection were studied. Although in rare cases, HBV-DNA was detectable before hepatitis B surface antigen (HBsAg) and e antigen (HBeAg), in the majority the viral proteins appeared first. In acute hepatitis followed by recovery, as IgM anti-HBc (hepatitis B core antigen) titres rose, the level of HBV replication fell and serum transaminases became elevated. In patients progressing to chronic HBV infection, IgM anti-HBc titres rose early, viral replication was initially low but continued to rise as the serum transaminase levels became elevated. 7S IgM anti-HBc, although present in the phase of established chronic HBV infection, was not found in the early phase of the chronic infection. Thus this antibody appears to be a consequence of, rather than a causative factor in, chronic HBV infection.  相似文献   
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