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71.
The transperineal percutaneous template permanent iodine interstitial brachytherapy under "C-arm" fluoroscopic guidance is a simple, easily-learned, accurate and rapid procedure which can be performed without subjecting the patient to celiotomy. We have treated 58 patients by the transperineal percutaneous permanent interstitial brachytherapy. The use of transperineal percutaneous technique with C-arm fluoroscopic guidance improves the symmetry and dosimetry of the implant. This results in reduction of the incidence of chronic radiation-induced complications. In the group of 22 patients who underwent brachytherapy without celiotomy and lymphadenectomy and without adjuvant external-beam radiotherapy, there were no major complications.  相似文献   
72.
A massive hemispheric high-grade astrocytoma, diagnosed in a 6-week-old infant, was totally excised by means of two craniotomies. The child is still alive and well with minimal neurological dysfunction 1.5 years after operation. This case report illustrates the benefit of aggressive surgical excision (without radiation or chemotherapy) of massive malignant neonatal astrocytomas. While surgical deficits may be minimized by the plasticity of the developing nervous system, extensive excision may yield occasional long-term palliation.  相似文献   
73.
Toxicologic analysis cannot supplant physician skills in the diagnosis and management of poisoning; however, it is a useful adjunct when properly used. Laboratory use should reflect critical consideration of clinical contribution as well as insight into institutional capability. A detailed historic review and interview of multiple sources may provide more useful and expeditious information than the blind "drug screen." Test ordering should be limited to that which directly contributes to clinical patient management.16 Similarly, test results must be interpreted in the clinical context of patient presentation. The reported units of measurement must be carefully scrutinized; and the potential for laboratory error must be appreciated. Most importantly, communication and cooperation must be maintained between the physician and laboratory personnel if the resource is to be optimally used.  相似文献   
74.
The International Labour Office (ILO) classification of radiographs of pneumoconiosis is a standard means of assessing the presence or absence of pneumoconiosis in workers exposed to mineral dusts. Using this classification, 200 admission chest radiographs were reviewed on hospitalized patients in an urban university medical center to determine the prevalence and possible significance of "small opacities" in a population without known industrial exposure. Seventy-one men and 129 women were screened with the mean age of 44.2 years (range, 15-84). Thirty-six (18%) of the 200 patients had small opacities at profusion level 1/0 or greater, and this constituted the "positive radiographs" group. Twenty-two patients (11%) with positive radiographs had no documentable dust exposure or other specific medical etiology that would explain the presence of their lung opacities. The high prevalence of small opacities in "normal" older individuals has important implications in the assessment of patients with suspected pneumoconiosis.  相似文献   
75.
Carcinoma of the esophagus with adenoid cystic differentiation   总被引:6,自引:0,他引:6  
J I Epstein  D L Sears  R S Tucker  J W Eagan 《Cancer》1984,53(5):1131-1136
Adenoid cystic carcinoma of the esophagus is a relatively rare lesion which characteristically exhibits a clinically aggressive behavior. In spite of this aggressive nature, it is most often referred to as a counterpart of the more common adenoid cystic carcinoma of salivary gland origin, a comparatively indolent tumor. In this report, the clinical and pathologic findings in a series of six cases of esophageal adenoid cystic carcinomas are contrasted with those of typical salivary gland lesions, and also compared to similar tumors exhibiting "adenoid cystic" differentiation arising in other extrasalivary gland sites. It is concluded that the esophageal tumors, as well as certain similar lesions arising in other extrasalivary gland sites, represent a class of poorly differentiated basaloid neoplasms distinct both clinically and morphologically from the common adenoid cystic carcinoma of salivary gland origin.  相似文献   
76.
The European Journal of Health Economics - Economic evaluation of health technologies requires healthcare resources, procedures and services to be valued at their opportunity cost. In practice,...  相似文献   
77.
The buffering effect of social support on the negative effects of racism exposure on health outcomes has been mixed in prior studies regarding Asian Americans. Based on the stress-coping framework and using structural equation modelling (SEM) methods, we tested a theoretical model portraying simultaneous mediational paths from racism exposure to general physical and mental health through racism-related stress. Bootstrap analysis was used to test the indirect effects present in the model. Additionally, multi-group SEM analysis was conducted to investigate the moderation effect of social support from family and friends on the paths in the model. The sample consisted of 310 Asian American adults who completed an online survey. The results from the two-step SEM analysis and bootstrap analysis supported the theoretical model—racism exposure can simultaneously have a negative indirect effect on Asian Americans' physical and mental health via racism-related stress. Multi-group SEM analysis showed that there were no differences in model path coefficients based on having varying levels of social support from friends or family.  相似文献   
78.

Syphilis among men who have sex with men (MSM) has increased greatly in the past twenty years in the U.S. Geographically explicit ecological momentary assessment (GEMA), in which behaviors are geotagged and contextualized in time and space, may contribute to a greater understanding of transmission risk. The objective was to determine the acceptability and feasibility of GEMA for assessing HIV and syphilis transmission risk behaviors among a sample of MSM. Participants responded to a brief survey five times a day for two weeks. Feasibility was measured by participant recruitment, enrollment, prompts received and answered, geotagged prompts, and technical interference with data collection. Acceptability was measured by ratings of enjoyment and willingness for future participation. Summaries of five behavioral measures from the brief survey were calculated. Among the 83 participants contacted, 67.5% (56) expressed interest, 98% (55) were scheduled, and 81.8% (45) were enrolled. Participants answered 78.3% (2,277) of prompts received and 87.7% (1,998) of answered prompts were geotagged. Overall, 70.5% (31) enjoyed participating and 91.1% (41) were willing to participate in the future. Among prompts answered, missingness was low for five behavioral measures (range 0.2% (4) to 0.7% (16)). Feasibility and acceptability were high and missingness was low on behavioral measures in this MSM study population. Most participants reported that they would participate again. Future work should focus on whether GEMA improves our understanding of syphilis and HIV transmission risk.

  相似文献   
79.
On-line radiotherapy imaging with an array of fiber-optic image reducers   总被引:1,自引:0,他引:1  
In the optical approach for on-line radiotherapy imaging, a large metal sheet-fluorescent screen combination is used to convert the radiation intensity distribution into a visible light image. Data are then captured via a mirror with a camera located out of the beam. Although usable portal images can be acquired, presence of the large mirror renders the system impractical in many treatment geometries. We have overcome this limitation by replacing the mirror with an array of 16 by 16 bundles of plastic fiber-optic image reducers. Each bundle, in turn, is made up of 16 by 16 individual optical fibers. The total of 256 by 256 fibers spans an input area of 40 cm by 40 cm with each individual fiber viewing an area of 1.6 mm by 1.6 mm. Within a height of 12 cm, each fiber is reduced to an area of 0.1 mm by 0.1 mm. The reduced portal image is then turned and "piped" to a final 3.0 cm by 3.0 cm output area. For data acquisition and digitization, the fiber output is directly coupled to the sensor of a TV camera interfaced to a small computer via a 512 by 512 frame grabber. In this initial evaluation, the imaging system has been characterized in terms of its line spread function, noise and resistance to radiation damage. Adequate phantom and patient images are presented.  相似文献   
80.
Both acute and chronic alcohol consumption can compromise kidney function, particularly in conjunction with established liver disease. Investigators have observed alcohol-related changes in the structure and function of the kidneys and impairment in their ability to regulate the volume and composition of fluid and electrolytes in the body. Chronic alcoholic patients may experience low blood concentrations of key electrolytes as well as potentially severe alterations in the body's acid-base balance. In addition, alcohol can disrupt the hormonal control mechanisms that govern kidney function. By promoting liver disease, chronic drinking has further detrimental effects on the kidneys, including impaired sodium and fluid handling and even acute kidney failure.  相似文献   
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