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101.
This prospective study compared images obtained with a photostimulable imaging plate with matched images obtained with a conventional screen-film combination in 26 patients undergoing intraoperative arteriography. Diagnostic accuracy of the two techniques was assessed objectively, and image quality was assessed subjectively. In 16 patients (62%), the radiation exposure was reduced by 50% for the imaging plate technique by decreasing the mAs level generally used for the screen-film combination. Because of the dynamic range of the imaging plate system, no repeat examinations were necessary, while 12% of the screen-film studies had to be repeated because of over- or under-penetration. Imaging plate studies required 6% more time for processing than screen-film studies. Receiver-operating-characteristic analysis indicated no difference in diagnostic accuracy between the two imaging techniques. Subjective evaluation also revealed no difference in observer preference for imaging plate or screen-film studies. The imaging plate technique is an excellent alternative to screen-film studies in the operating room.  相似文献   
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103.
The gene for autosomal recessive spinal muscular atrophy (SMA) has been mapped to 5q12 in a region that contains repeated markers and genes. Three cDNAs that detect deletions in SMA patients have been reported. One of these, the survival motor neuron (SMN) cDNA, is encoded by two genes (SMNT and SMNC) which are distinguished by base changes in exons 7 and 8. Exon 7 of the SMNT gene is not detectable in approximately 95% of SMA cases, due either to deletion or sequence conversion. There is limited information on the mutations in SMA patients that have detectable SMNT, these are critical for confirmation of SMNT as the SMA gene. Using SSCP analysis of the SMN exons we screened our SMA patients that possess at least one intact SMNT allele for mutations in SMNT. We identified one type I SMA patient with an 11 bp duplication in exon 6 which causes a frameshift and premature termination of the deduced SMNT protein. Dosage and SSCP analysis of SMNT in this family indicated that the father contributed a SMNT-deleted allele to the affected child whereas the mother passed on the 11 bp exon 6 duplication SMNT allele. Analysis of RNA by RT-PCR conclusively demonstrated that the 11 bp duplication is associated with the SMNT locus and not SMNC. This mutation provides strong support for SMN as the SMA-determining gene and indicates that disruption of SMNT on its own is sufficient to produce a severe type I SMA phenotype.   相似文献   
104.
105.
An unusual case of acute isopropanol overdose which occurred within the confines of the emergency department is reported. Serial serum concentrations of isopropanol and its metabolite acetone were followed for 43 hours. Pharmacokinetic analysis is presented, as well as a brief literature review of diagnosis and management. CNS toxicity was related mainly to isopropanol concentrations. The calculated half-life of isopropanol was 7.3 hours. Because of the pharmacokinetic profile of isopropanol, management decisions regarding the use of hemodialysis should be made within one to two hours of patient presentation.  相似文献   
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107.
In 2018, there will be approximately 22,240 new cases of ovarian cancer diagnosed and 14,070 ovarian cancer deaths in the United States. Herein, the American Cancer Society provides an overview of ovarian cancer occurrence based on incidence data from nationwide population‐based cancer registries and mortality data from the National Center for Health Statistics. The status of early detection strategies is also reviewed. In the United States, the overall ovarian cancer incidence rate declined from 1985 (16.6 per 100,000) to 2014 (11.8 per 100,000) by 29% and the mortality rate declined between 1976 (10.0 per 100,000) and 2015 (6.7 per 100,000) by 33%. Ovarian cancer encompasses a heterogenous group of malignancies that vary in etiology, molecular biology, and numerous other characteristics. Ninety percent of ovarian cancers are epithelial, the most common being serous carcinoma, for which incidence is highest in non‐Hispanic whites (NHWs) (5.2 per 100,000) and lowest in non‐Hispanic blacks (NHBs) and Asians/Pacific Islanders (APIs) (3.4 per 100,000). Notably, however, APIs have the highest incidence of endometrioid and clear cell carcinomas, which occur at younger ages and help explain comparable epithelial cancer incidence for APIs and NHWs younger than 55 years. Most serous carcinomas are diagnosed at stage III (51%) or IV (29%), for which the 5‐year cause‐specific survival for patients diagnosed during 2007 through 2013 was 42% and 26%, respectively. For all stages of epithelial cancer combined, 5‐year survival is highest in APIs (57%) and lowest in NHBs (35%), who have the lowest survival for almost every stage of diagnosis across cancer subtypes. Moreover, survival has plateaued in NHBs for decades despite increasing in NHWs, from 40% for cases diagnosed during 1992 through 1994 to 47% during 2007 through 2013. Progress in reducing ovarian cancer incidence and mortality can be accelerated by reducing racial disparities and furthering knowledge of etiology and tumorigenesis to facilitate strategies for prevention and early detection. CA Cancer J Clin 2018;68:284–296 . © 2018 American Cancer Society .  相似文献   
108.
Increased emphasis on strict glycaemic control of insulin dependent diabetes mellitus (IDDM) in young patients may be expected to cause increases in rates of significant hypoglycaemia. To evaluate whether this is the case for a large population based sample of IDDM children and adolescents rates of severe (coma, convulsion) and moderate (requiring assistance for treatment) hypoglycaemia were studied prospectively over a four year period. A total of 709 patients were studied yielding 2027 patient years of data (mean (SD) age: 12.3 (4.4); range 0-18 years, duration IDDM: 4.9 (3.8) years). Details of hypoglycaemia were recorded at clinic visits every three months when glycated haemoglobin (HbA1c) was also measured. Overall the incidence of severe hypoglycaemia was 7.8 and moderate was 15.4 episodes/100 patient years. Over the four years mean (SD) clinic HbA1c steadily fell from 10.2 (1.6)% in 1992 to 8.8 (1.5)% in 1995. In parallel with this there was a dramatic increase in the rate of hypoglycaemia, especially in the fourth year of the study, when severe hypoglycaemia increased from 4.8 to 15.6 episodes/100 patient years. This increase was particularly marked in younger children (< 6 years) in whom severe hypoglycaemia increased from 14.9 to 42.1 episodes/100 patient years in 1995. It is concluded that attempts to achieve improved metabolic control must be accompanied by efforts to minimise the effects of significant hypoglycaemia, particularly in the younger age group.  相似文献   
109.
时岩  孙林潮  高天文 《医学争鸣》1999,20(9):826-826
0 引言 东方人接受皮肤磨削术治疗后色素沉着的发生率明显高于西方人.尽管采用了目前被认为是最适宜亚洲人的铒激光治疗,色素沉着仍可发生.因此,在实施该手术治疗前应严格掌握适应证,制定严密的预防治疗措施,使得色素沉着的发生率降至最低,从而最大限度的防止医疗纠纷的发生.1 对象和方法1.1 对象 21例患者,男2例,女19例,平均年龄29.2(08~48)岁.皱纹祛除8例,浅表疤痕7例,浅咖啡斑、黑子5例,不良纹眉1例.铒激光其它适应证:①老年斑;②细小皱纹;③“白皮肤”雀斑;④痤疮后疤痕⑤色素减退…  相似文献   
110.
The authors present a set of curriculum guidelines in integrative medicine for medical schools developed during 2002 and 2003 by the Education Working Group of the Consortium of Academic Health Centers for Integrative Medicine (CAHCIM) and endorsed by the CAHCIM Steering Committee in May 2003. CAHCIM is a consortium of 23 academic health centers working together to help transform health care through rigorous scientific studies, new models of clinical care, and innovative educational programs that integrate biomedicine, the complexity of human beings, the intrinsic nature of healing, and the rich diversity of therapeutic systems. Integrative medicine can be defined as an approach to the practice of medicine that makes use of the best-available evidence taking into account the whole person (body, mind, and spirit), including all aspects of lifestyle. It emphasizes the therapeutic relationship and makes use of both conventional and complementary/alternative approaches. The competencies described in this article delineate the values, knowledge, attitudes, and skills that CAHCIM believes are fundamental to the field of integrative medicine. Many of these competencies reaffirm humanistic values inherent to the practice of all medical specialties, while others are more specifically relevant to the delivery of the integrative approach to medical care, including the most commonly used complementary/alternative medicine modalities, and the legal, ethical, regulatory, and political influences on the practice of integrative medicine. The authors also discuss the specific challenges likely to face medical educators in implementing and evaluating these competencies, and provide specific examples of implementation and evaluation strategies that have been found to be successful at a variety of CAHCIM schools.  相似文献   
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