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91.
Eighty-seven different mineral waters available for purchase in the Federal Republic of Germany were tested for the presence of heterotrophic bacteria and, specifically, antibiotic-resistant Pseudomonas species. Waters lacking carbon dioxide and Heilwasser (waters often prescribed for a variety of ailments) tended to show the highest numbers of bacteria. Eighty-one isolates of Pseudomonas were obtained from 39 samples of mineral water. Of the 9 species found, P. cepacia and P. maltophilia, most commonly associated with nosocomial infections, made up 13. 6% of the isolates. These 2 species also showed the highest resistance to the ten antibiotics used in the study. A comparison of antibiotic resistance patterns between mineral water and clinical isolates from the Medizinische Hochschule, Hannover, shows a higher similarity than that between mineral water and Massachusetts General Hospital (Boston) isolates. With the exception of P. pseudoalcaligenes, all mineral water isolates showed basically 100% resistance to cefoxitin and were highly resistant to ampicillin. Only 1 of 81 isolates (1. 2%) was resistant to tobramycin, although 2 isolates of P. cepacia showed intermediate resistance to this drug. Though no P. aeruginosa were found in any of the samples, the presence of species associated with nosocomial infections and highly resistant to commonly used antibiotics suggests that careful thought be given to the routine ingestion of mineral water by compromised individuals and those with underlying disease.  相似文献   
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Bricks collected from a contaminated village (Muslyumovo) of the lower Techa river valley, Southern Urals, Russia, were measured using thermoluminescence and optically stimulated luminescence by four European laboratories and a U.S. laboratory to establish and compare the applied dose reconstruction methodologies. The bricks, collected from 60-100-year-old buildings, had accumulated a relatively high dose due to natural sources of radiation in the brick and from the surrounding environment. This work represents the results of a first international intercomparison of luminescence measurements for bricks from the Southern Urals. The luminescence measurements of absorbed dose in bricks collected from the most shielded locations of the same buildings were used to determine the background dose due to natural sources of radiation and to validate the age of the bricks. The absorbed dose in different bricks measured by four laboratories using thermoluminescence and optically stimulated luminescence at a depth of 10 +/- 2.5 mm from the exposed brick surface agreed within +/-21%. After subtraction of the natural background dose, the absorbed dose in brick due to contaminated river sediments and banks was calculated and found to range between 150 and 200 mGy. The cumulative doses in brick due to man-made sources of radiation at 100 and 130 mm depths in the bricks were also measured and found to be consistent with depth dose profiles calculated by Monte Carlo simulations of photon transport for possible source distributions.  相似文献   
94.
A bstract The right gastroepiploic artery (RGEA) has been utilized as the bypass conduit on the inferior surface of the heart with a minimally invasive approach. Fourteen patients had reoperative coronary bypass surgery for severely symptomatic single-vessel disease of the right coronary artery. All surgeries were performed since May 1996. A small mid-line incision including splitting of the lower sternum gave excellent exposure. The inferior surface of the heart was dissected to expose and stabilize the target vessel. The heart rate was controlled with a diltiazem drip. Cardiopulmonary bypass was not necessary in any case. The right coronary artery was bypassed in three patients, the posterior descending artery branch in ten patients, and the terminal circumflex of the left coronary artery in one. After grafting, patency of the anastomosis was demonstrated by Doppler echocardiogram. Two patients had left anterior descending artery (LAD) grafts with LIMA (left mammary artery) and RGEA grafts performed simultaneously with two port access incisions. No patient had perioperative mortality or complications. No patient had recurrent angina. Doppler color echocardiographic imaging studies before discharge confirmed patency of the graft in 13 of 14 cases. In one case, the gastroepiploic artery could not be visualized. Angiographic visualization was positive in seven cases; seven patients were not studied yet. The gastroepiploic artery is an excellent conduit for vascularization of the inferior aspect of the heart. The operation can be done with a minimally invasive technique and without the use of cardiopulmonary bypass. This approach seems especially applicable in selective reoperative cases.  相似文献   
95.
This report describes the efficacy and toxicity of PAVe (procarbazine, Alkeran, vinblastine) and irradiation (RT) in the management of 159 patients with locally extensive or advanced stage Hodgkin's disease (HD) at Stanford University. Patients received six courses of chemotherapy alternating with RT. The extent of RT and the schedule of treatment varied according to the stage of disease. About 2/3 of patients received PAVe/RT in the setting of prospective, randomized clinical trials. The rate of complete response was 93%. With a median follow-up of seven years (range 2-17), the 15 year actuarial freedom from progression (FFP) is 78% and overall survival is 75%. Ten-year FFP by stage is: 80% for locally extensive stage II, 90% for stage IIIA and 70% for stage IIIB. Excellent and equal results were attained with PAVe/RT vs. MOP(P) (mustard, Oncovin, procarbazine with or without prednisone)/RT in the randomized combined modality studies. Progression or recurrence was documented in 30 patients and was more common in irradiated sites. PAVe was well tolerated acutely. There were no treatment related fatalities. Twenty-three (14%) patients were admitted to the hospital for neutropenic fever. Five second malignancies have occurred after PAVe/RT only: one myelodysplastic syndrome, one acute myelogenous leukemia, one non-Hodgkin's lymphoma and two solid tumors including a case of non-small cell lung cancer and an in situ carcinoma of the cervix. Three patients died from myocardial infarction several years after the completion of treatment. These mature data show that PAVe/RT is effective and well-tolerated therapy for locally extensive stage II and IIIA/B HD.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Peroneus quartus muscle: MR imaging features   总被引:2,自引:0,他引:2  
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100.
To determine whether the Osgood-Schlatter lesion (OS) is produced by avulsion fracture or injury to the patellar tendon, all images obtained in 28 cases of OS in 20 patients (16 scintigrams, 34 computed tomographic [CT] scans, and 27 magnetic resonance [MR] images) were retrospectively analyzed. In 21 cases, imaging was performed before and after treatment; in 20 cases, relief from pain was complete at the time of repeat examination. In all patients (100%), abnormal size of the tendon, decreased attenuation, and increase in signal intensity were compatible with the CT and MR imaging appearance of tendinitis. Distended deep infrapatellar bursa was a frequent finding, particularly on MR studies. These abnormalities had partially disappeared at follow-up examination. An ossicle was seen in only nine of 28 cases (32%); in three of seven cases with follow-up, the ossicle remained nonunited to the tibial tuberosity on follow-up studies despite relief from symptoms. This implies that healing of fracture is not essential for relief from symptoms. These results strengthen the argument that in most cases of OS, insult to the tendon and associated soft tissues, rather than avulsion fracture, causes OS.  相似文献   
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