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71.
72.
Insertion of a screw biopsy stylet into a thin-walled biopsy needle greatly enhances detection of the needle during ultrasound-guided percutaneous biopsy. This technique is helpful when precise needle-tip localization is needed for biopsies of small lesions.  相似文献   
73.
The mode of action of the Kensey catheter, a new atheroablation device, was investigated. Fresh above-the-knee amputated legs were used for recanalization of the superficial femoral artery. The variables used were identical to those of clinical trials, including a rotational speed of 50,000 rpm and an injection rate of 40 mL/min. The debris produced by the catheter was studied cytologically, and the arterial segments were examined histologically. The particle size in the debris ranged from 1 to 2,000 microns. The softer plaques produced a fine fibrin dust background with long strips of intima ranging from 10 to 2,000 microns. Complicated calcified plaques produced larger background material (10-120 microns) but smaller strips of intima (50-800 microns). Dissections and perforations occurred. Some of the debris produced by the atheroablation process was used to embolize a canine heart and kidney. Small focal infarctions were found in the heart, and large and multiple infarcts were seen in the kidney. In clinical studies the debris appears to be tolerated in the lower extremities. Its safety in the kidney and heart are questioned.  相似文献   
74.
Garel  LA; Belli  D; Grignon  A; Roy  CC 《Radiology》1987,165(3):639-641
Percutaneous cholecystography was performed on 13 children who had biliary system abnormalities: two had biliary hypoplasia, five had sclerosing cholangitis, three had cirrhosis, two had distal choledochal obstruction, and one had an obstructed portoenterostomy. In 12 patients transcholecystic cholangiography showed, without significant complications, the intra-and extrahepatic bile ducts. In one patient with primary sclerosing cholangitis, the intrahepatic bile ducts were not opacified satisfactorily; dilatation of the gallbladder required surgical drainage. The transcholecystic technique is indicated when the intrahepatic bile ducts are either mildly dilated or not dilated.  相似文献   
75.
The efficacy and safety of ceftazidime were compared with those of carbenicillin and amikacin in 60 neonates with proved invasive bacterial infections. The two treatment groups of patients were comparable with regard to sex, gestational and chronologic ages, associated risk factors, clinical condition on enrollment, focus of infection and bacteriology. Escherichia coli was isolated from blood cultures of 31%, Pseudomonas aeruginosa from cultures of 25%, Klebsiella sp. from cultures of 13% and other Gram-negative enteric bacilli from cultures of 17% of the patients. Staphylococcus aureus was isolated from 20% (12 of 60), and coagulase-negative staphylococci from 8% (5 of 60) of the patients. All Gram-negative coliform bacilli were susceptible to ceftazidime whereas 10, 56 and 77% were resistant to amikacin, carbenicillin and ampicillin, respectively. Serum bactericidal activity against the offending pathogen was as much as 5-fold greater in ceftazidime-treated compared with conventionally treated patients. Seven patients with infections caused by organisms resistant to the study drugs were excluded from analysis. Case-fatality rates were 6.4% (2 of 31) and 21% (6 of 28) in the ceftazidime- and amikacin/carbenicillin-treated patients, respectively. Total failure rates, including deaths, were significantly higher in patients treated with amikacin/carbenicillin (8 of 28, 28.5%) compared with that of ceftazidime-treated patients (2 of 31, 6.4%). Thirteen percent (5 of 31) and 3% (1 of 28) of the ceftazidime- and amikacin/carbenicillin-treated patients, respectively, developed invasive Candida albicans superinfection while receiving treatment. In this study results of treatment with ceftazidime were superior to results of treatment with amikacin/carbenicillin for invasive bacterial infections of newborn infants.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
76.
77.
B G Krohn  J M Saenz  K K Eto 《Chest》1989,95(4):729-734
This study was conducted to ascertain if critical peak body stores of digoxin were needed to protect patients from the debilities that result from supraventricular tachycardias occurring after open heart operations. We gave digoxin peak body stores of 15 micrograms/kg of lean body weight to 100 consecutive patients after open heart operations. If supraventricular tachycardias persisted four hours, we increased peak body stores to 17 or 19 micrograms/kg. The operations included coronary artery bypass grafts, heart valve replacements, and congenital defect correction. After operation, 18 patients had atrial fibrillation or flutter. During supraventricular tachycardias, ventricular rates were 150 beats per minute or slower. In the 100 patients, the median hospital stay after operation was four days. No patient required rehospitalization. The patients who had supraventricular tachycardias stayed in the hospital no longer than the patients who were at all times in regular sinus rhythm. All patients who entered the hospital with regular sinus rhythm went home with regular sinus rhythm. The critical safe peak body stores of digoxin needed to prevent debilities resulting from supraventricular tachycardias after open heart operations were 15 to 19 micrograms/kg of lean body weight.  相似文献   
78.
79.
We have tested the analgesic and antipyretic activity of the aqueous extract obtained from Pycnocomon rutifolium for various stimulations. Previously we have made a phytochemic screening and an assay of acute toxicity.  相似文献   
80.
Congenital heart defects are classified into two broad categories: acyanotic and cyanotic lesions. The most common acyanotic lesions are ventricular septal defect, atrial septal defect, atrioventricular canal, pulmonary stenosis, patent ductus arteriosus, aortic stenosis and coarctation of the aorta. Congestive heart failure is the primary concern in infants with acyanotic lesions. The most common cyanotic lesions are tetralogy of Fallot and transposition of the great arteries. In infants with cyanotic lesions, hypoxia is more of a problem than congestive heart failure. Suspicion of a congenital heart defect should be raised by the presence of feeding difficulties in association with tachypnea, sweating and subcostal recession, or severe growth impairment. Follow-up of infants with congenital heart disease should follow the schedule of routine care for healthy babies with some modifications, such as administration of influenza and pneumococcal vaccines. More frequent follow-up is required if congestive heart failure is present. Family psychosocial issues should also be addressed. One of the main roles for the family physician is to help the parents put the diagnosis in perspective by clarifying expectations and misconceptions, and answering specific questions.  相似文献   
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