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A bstract Isolated mitral valve replacement using the CarboMedics prosthetic mitral valve (CarboMedics, Inc., Austin, TX) was studied in 13 centers in the United States, Canada, and Scandinavia between 1987 and 1993 in 428 patients with a mean age of 57 ± 14 years. Actuarial survivals at 1, 2, and 5 years were 88.2% and 75.8%. Freedom from events at 5 years were 94.8% for major thromboembolism, 96.6% for thrombosis, and 96.7% for endocarditis. Linearized morbidity rates (events per 100 patient years) for events at > 30 days postoperatively were .51 thrombosis, 1.1 major thromboembolism, and .37 endocarditis. These results at early to mid-term compare favorably with the first generation bileaflet valve.  相似文献   
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The development of current concepts in the treatment of breast diseases during the last 100 years is well documented in the Transactions of the Southern Surgical Association. Fellows of the SSA have been on the cutting edge of these developments and chose the SSA as the forum to describe and debate their new observations.  相似文献   
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Individual larvae, pupae, female adults, and adult body parts of Anopheles arabiensis Patton and An. gambiae Giles were stored for 1 mo either in isopropanol at room temperature, over a desiccant at room temperature, or at -70 degrees C. DNA was extracted, digested with EcoR1 restriction enzyme, subjected to electrophoresis in agarose gel, transferred to filters, then hybridized to a 32P-labeled rDNA probe. There was no difference among storage treatments in the proportion of correctly identified samples. First instars were not identifiable. Pupae and female adults were more likely to be identified than earlier life history stages. Nonetheless, the probe identified greater than 75% of second instars, 94% of third instars, and 74% of fourth instars. There were no differences between the species in the proportion of identifiable samples for any life history stage.  相似文献   
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Summary The effectiveness of nifedipine retard as a treatment for Raynaud's phenomenon was assessed in 15 patients in a placebo controlled double blind study. An associated connective tissue disease was evident in 7 patients. Changes in finger and forearm blood flow (venous occlusion plethysmography), digital skin temperature and digital systolic pressure were measured acutely before and after a 2-week treatment period. Subjective assessment of efficacy was based on patient diary data. In addition alpha2-adrenoceptor density on platelets was measured before and after chronic nifedipine therapy in both the patient group and in an age-and-sex-matched control group. No significant haemodynamic changes were observed. Nifedipine retard significantly reduced the frequency (p<0.05) with no change in either the duration or severity of vasospastic attacks. Side effects were commono following nifedipine retard. A reduction in alpha2-adrenoceptor density on platelets was observed in patients compared to a control group (p<0.05). Alpha2-adrenoceptor density was unchanged following a 2-week treatment period with nifedipine retard. This study concludes that nifedipine retard is not effective in the treatment of Raynaud's phenomenon over a short time course. Patients with Raynaud's phenomenon have reduced alpha2-adrenoceptor densities on their platelets.  相似文献   
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Solid and papillary epithelial neoplasms of the pancreas: CT findings   总被引:1,自引:0,他引:1  
Choi  BI; Kim  KW; Han  MC; Kim  YI; Kim  CW 《Radiology》1988,166(2):413-416
Five female patients and one male patient with solid and papillary epithelial neoplasms of the pancreas were examined with computed tomography (CT). The mean age of the patients was 27 years (range, 13-46 years). All cases showed well-encapsulated, round or lobulated masses consisting of both cystic and solid areas. Cystic portions showed CT numbers that suggested hemorrhagic necrosis. There were no internal septations within the masses. In three tumors located in the head of the pancreas, dilatation of the biliary tree was absent or minimal, although the masses were large. Two tumors contained calcifications. One tumor demonstrated metastatic deposits in liver and lymph nodes. Metastatic masses appeared similar to the primary pancreatic mass. Solid and papillary neoplasm of the pancreas should be the primary diagnostic consideration when characteristic CT findings are detected in a young female patient.  相似文献   
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The Liverpool Continuing Health in the Community Study has followed up 1070 elderly community subjects over 6 years. In the first year 123 subjects had case-level depression. Three years later 49 (39.8%) of the previously depressed were recovered, 33 (26.8%) were depressed, 16 (13%) were not available for interview and 25 (20.3%) were dead. This study looks at factors associated with the 3-year outcome of patients who were depressed at year 0. Two outcome groups that were compared were a recovered depression group and a recurrent/persistent depression group. The factors that were significantly associated with a recurrence of depression (or persistent depression) at year 3 were bereavement of a close figure in the 6 months before interview, loneliness and life dissatisfaction at year 3. A variety of traditional risk factors for depression (including age, marital status, physical ill-health and incapacity) failed to attain significance in predicting recurrent or persistent depression. When combined, both recovered and recurrently depressed groups at year 3 had significantly higher levels of pain and a higher number of serious upsets in the past 6 months and 6 weeks compared to a compared to a control group. The depressed at year 0 were more likely to have entered more dependent forms of accommodation by year 3.  相似文献   
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Neuropsychological outcome of 28 patients with brain tumors diagnosed before the age of 36 months (mean, 19 months) was assessed using a comprehensive battery of tests. Elapsed time between diagnosis and testing averaged 6.2 years. Half the patients had received cranial radiation therapy and surgery, with and without chemotherapy, whereas the rest had received only surgery, with or without chemotherapy. Groups were comparable with respect to tumor diagnosis and location, age at diagnosis, race, and sex. Intellectual functioning was significantly lower in children whose treatment included cranial irradiation than in those treated without cranial irradiation, and this effect was more pronounced in nonverbal than in verbal intellectual abilities. Mean scores for the radiation group were lower than for the no-radiation group in all areas assessed and were significantly below age-based normative means in five of the eight cognitive areas: intellectual, memory, attention, motor, and visual-spatial skills. Mean scores for children in the no-radiation group were generally within the average range in all cognitive areas except visual-spatial skills, which were significantly below age-based normative means. Endocrine deficiencies and growth retardation were much more prevalent in patients treated with cranial irradiation. Because the immature brain is susceptible to treatment-related pathologic changes, infants are at greater risk than older children for significant, long-term neuropsychological, endocrine, and growth sequelae. In children treated without cranial irradiation, morbidity was minimized without an increased rate of mortality.  相似文献   
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