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排序方式: 共有7243条查询结果,搜索用时 31 毫秒
991.
992.
Mimicry in pulmonary embolism 总被引:1,自引:0,他引:1
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Localization of pancreatic insulinoma: comparison of pre- and intraoperative US with CT and angiography 总被引:2,自引:0,他引:2
Galiber AK; Reading CC; Charboneau JW; Sheedy PF d; James EM; Gorman B; Grant CS; van Heerden JA; Telander RL 《Radiology》1988,166(2):405-408
Methods of preoperative radiologic localization of insulinoma were compared in 52 patients, 44 of whom had solitary tumors. Examinations performed in these 44 patients were preoperative ultrasonography (US) in 28, angiography in 26, and computed tomography in 23. Prospective sensitivities were 61%, 54%, and 30%, respectively. Imaging sensitivities were lower for the eight patients with multiple insulinomas. In 28 of the 44 patients, intraoperative US was performed without the examiner being aware of the surgical findings. The sensitivity was 84%. Four insulinomas were not palpable but were visualized sonographically. The combined sensitivity of intraoperative US and surgical palpation for detecting solitary insulinomas was 100%. High-frequency intraoperative US is valuable for detecting occult solitary insulinomas and considerably useful for determining the proximity of insulinomas to the pancreatic and bile ducts. 相似文献
998.
Genetic variants of HIV-1 in Thailand. 总被引:40,自引:0,他引:40
F E McCutchan P A Hegerich T P Brennan P Phanuphak P Singharaj A Jugsudee P W Berman A M Gray A K Fowler D S Burke 《AIDS research and human retroviruses》1992,8(11):1887-1895
Serosurveys conducted prior to 1988 indicated a very low level of HIV-1 infection in Thailand, even among high-risk groups. The Ministry of Health has reported a dramatic increase in HIV-1 infection during the last three years. The geographic and demographic distribution of the epidemic is broad, involving multiple provinces and risk groups. Foci of higher incidence and prevalence have been noted in the urban center of Bangkok and in the northern provinces of Chiang Mai and Chiang Rai. Here we report the results of genetic characterization of 16 HIV-1 isolates from Thailand using a combination of polymerase chain reaction (PCR) typing and DNA sequencing. The complete sequence of gp160 (env) of five isolates, partial env sequence of six additional isolates, and the gag gene of two isolates were determined. Two highly distinct HIV-1 variants were found. One variant resembled those prevalent in North America and Europe; five of the isolates were of this type. The remaining eleven isolates were very similar to one another and represented a variant unlike any previously described. Phylogenetic tree analysis of complete env and gag genes placed the two variants on widely separated branches. Protein sequence comparisons indicate both general and specific features that distinguish the Northern Thailand variant both from the Bangkok variant and from virtually all previously sequenced HIV-1 isolates. A simple PCR test for distinguishing the two variants has been developed for use in epidemiologic surveys. 相似文献
999.
A Delphi technique was used to ask general practitioners for their opinions as to which clinical problems and types of measure they thought most appropriate for the development of outcome measures for use in primary health care. The study comprised two rounds of postal questionnaires, targeted at general practitioners in academic departments throughout the United Kingdom and at trainers in the northern region, with the second questionnaire feeding back opinions from the first. Ninety eight participants suggested one or more areas in which outcome measures could be developed, giving a total of 451 suggestions. Consensus produced in the second round indicated that three clinical conditions were preferred for the development of outcome measures: asthma, diabetes and hypertension. Six categories of outcome measures were developed from the responses given in the first round--level of function, level of clinical control, incidence of complications, iatrogenic problems, patient understanding of a condition, and quality of life. Participants gave these measures different levels of importance according to the clinical problem in question. This Delphi study of doctors' opinions is a first step in the development process of appropriate, practicable measures of outcome for use in primary care and has achieved a degree of consensus among general practitioners. 相似文献
1000.
Symptom status and quality of life following prostatectomy 总被引:13,自引:0,他引:13
When prostatectomy is proposed as treatment for the symptoms of prostatism, the decision to operate should depend on how patients evaluate their symptoms and on objective information about the outcomes. We undertook a health interview study to determine the probabilities for symptom relief, improvement in the quality of life, and complications following surgery and to evaluate patient concern about the symptoms of prostatism. The operation was effective in reducing symptoms: 93% of severely and 79% of moderately symptomatic patients experienced improvement; however, a statistically significant improvement in indices of quality of life occurred only among patients with acute retention or severe symptoms prior to surgery. Short-term complications of varying severity occurred in 24% of patients; in addition, 4% reported persistent incontinence and 5%, impotence. Patients with similar symptoms reported considerable difference in the degree to which they were bothered by their symptoms. The result emphasizes the importance of patient participation in the decision to undergo prostatectomy. 相似文献