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排序方式: 共有3778条查询结果,搜索用时 15 毫秒
961.
962.
Kuppersmith RB Greco SC Teh BS Donovan DT Grant W Chiu JK Cain RB Butler EB 《Ear, nose, & throat journal》1999,78(4):238, 241-6, 248 passim
Intensity-modulated beam radiotherapy (IMRT) delivers a highly conformal, three-dimensional (3-D) distribution of radiation doses that is not possible with conventional methods. When administered to patients with head and neck tumors, IMRT allows for the treatment of multiple targets with different doses, while simultaneously minimizing radiation to uninvolved critical structures such as the parotid glands, optic chiasm, and mandible. With 3-D computerized dose optimization, IMRT is a vast improvement over the customary trial-and-error method of treatment planning. We retrospectively reviewed the charts of the first 28 head and neck patients at our institution who were treated with IMRT. All had head and neck neoplasms, including squamous cell carcinoma, adenoid cystic carcinoma, paraganglioma, and angiofibroma. Total radiation doses ranged from 1,400 to 7,100 cGy, and daily doses ranged from 150 to 400 cGy/day. A quality assurance system ensured that computer-generated dosimetry matched film dosimetry in all cases. For midline tumors, this system allowed us to decrease the dose to the parotid glands to less than 3,000 cGy. The incidence of acute toxicity was drastically lower than that seen with conventional radiotherapy delivery to similar sites. This is the first report of the application of IMRT strictly to head and neck neoplasms. We discuss the indications, technique, and initial results of this promising new technology. We also introduce the concept of the Simultaneous Modulated Accelerated Radiation Therapy boost technique, which has several advantages over other altered fractionation schemes. 相似文献
963.
We describe a new technique for tonsillectomy using dual-function scissors that cut and bipolar coagulate at the same time. The technique shortens operating time and decreases intra-operative blood loss. Forty patients had their tonsillectomy performed using this technique. The mean operating time was 5.5 min (SD 2.1) and mean blood loss was 1.3 ml (SD 3.6). All patients were able to eat and drink on the same postoperative day and all were discharged the following morning. None of the patients had primary haemorrhages and two patients (5%) had minor secondary haemorrhages. We found bipolar scissor tonsillectomy to be a safe technique that shortens surgery and minimises blood loss without causing increased postoperative morbidity. 相似文献
964.
Parasuraman S Rao BN Bodner S Cain A Pratt CB Merchant TE Pappo AS 《Pediatric hematology and oncology》1999,16(6):539-544
Clear cell sarcoma is a rare soft tissue neoplasm whose clinical behavior and outcome has not been previously characterized. This study reviewed the clinical characteristics and outcome of all children with clear cell sarcoma of the soft tissues who were treated at St. Jude Children's Research Hospital from March 1962 through August 1998. Of 225 children with nonrhabdomyosarcomatous soft tissue sarcomas, 5 (2.2%) were diagnosed with clear cell sarcoma. Median age at diagnosis was 15 years 3 months. Primary sites included the extremities (n = 3), chest wall (n = 1), and abdomen (n = 1). At diagnosis 3 patients had localized disease. Following surgical resection (n = 3), radiotherapy (n = 2), and chemotherapy (n = 1) all three survive disease-free 10, 11, and 90 months after diagnosis, respectively. The remaining two patients with metastatic disease at diagnosis died 21 days and 9 months after diagnosis. Clear cell sarcoma of the soft tissues is rare in pediatrics. Complete surgical resection with negative margins is the most effective treatment for this disease. Patients with metastatic disease are candidates for multiinstitutional chemotherapy trials. 相似文献
965.
A randomized prospective study of posterolateral lumbar fusion. Outcomes with and without pedicle screw instrumentation 总被引:8,自引:0,他引:8
France JC Yaszemski MJ Lauerman WC Cain JE Glover JM Lawson KJ Coe JD Topper SM 《Spine》1999,24(6):553-560
STUDY DESIGN: A prospective evaluation of the clinical and radiographic outcomes of 71 patients who underwent lumbar fusion, with or without transpedicular instrumentation. The patients completed a questionnaire that determined pain relief, medication use, return to work, and overall satisfaction with surgery. OBJECTIVES: To explore the effect, if any, of instrumentation on the outcome of lumbar fusion surgery, according to reports of the patients, and whether there is a correlation between the radiographic determination of a solid fusion and the same patient-reported outcome. SUMMARY OF BACKGROUND DATA: The literature on this topic reports pseudarthrosis rates from 0% to 57% and good to excellent results from 56% to 95%. These studies provide no clear-cut recommendations concerning the effect of added lumbar instrumentation on patient-reported outcome in a prospective manner using concurrent control subjects. METHODS: The patients were randomized to groups with and without instrumentation after deciding to undergo a lumbar fusion and consenting to enter the study. Radiographs were obtained and questionnaires filled out at 6 weeks, 6 months, 1 year, and 2 years after surgery. RESULTS: There was no statistical difference in patient-reported outcome between the two groups. There was a slight nonsignificant trend toward increased radiographic fusion rate in the group with instrumentation that did not correlate with an increased patient-reported improvement rate. CONCLUSIONS: These results do not provide data that indicate a benefit in outcome from added instrumentation in elective lumbar fusions. 相似文献
966.
967.
Unidentified coronary artery disease remains a significant cause of premature death and morbidity during the prime of life. The availability of effective interventions for the management of ischemia has provoked new interest in screening for this condition in asymptomatic patients, in the hope of reducing the burden of this condition. Although widespread use of stress testing is ineffective, the use of imaging techniques may offer better accuracy for detection of ischemia. Other tests that identify evidence of atheroma in the peripheral or coronary circulation may be useful to identify patients at risk. 相似文献
968.
Cain P 《Nurse education today》1999,19(3):175-181
Issues of confidentiality are an integral part of professional nursing practice, hence reflection on these issues is an integral part of nurse education. 'Respecting and breaking confidences: conceptual, ethical and educational issues' argues that reflection must take account of at least two conceptual issues, namely, what is confidential information? and what constitutes a breach of confidentiality? An answer to these questions is logically presupposed by the ethical questions considered, i.e. what should clients be told about the parameters of confidentiality at the first point of contact? and what would justify a breach of confidence? The discussion is anchored in a critique of the Advisory Paper (1987) on confidentiality, published by the United Kingdom Central Council for Nursing, Midwifery and Health Visiting. It concludes by drawing out some implications for nurse education. 相似文献
969.
J Enrique Cometto-Mu?iz William S Cain Michael H Abraham Ricardo Sánchez-Moreno 《Toxicological sciences》2006,91(2):600-609
In a series of experiments, we looked at a "cutoff" effect for the detection of eye irritation from neat vapors of homologous n-alkylbenzenes and 2-ketones. Stimuli comprised pentyl, hexyl, and heptyl benzene, 2-dodecanone, and 2-tridecanone, presented to each eye at 4 and 8 l/min for 6 sec, using a three-alternative forced-choice procedure against blanks. Detection probability corrected for chance (i.e., detectability) decreased with carbon chain length such that heptyl benzene and 2-tridecanone were virtually undetectable, irrespective of flow rate to the eye. Heating both stimuli sources to 37 degrees C (body temperature) from 23 degrees C (room temperature) increased vapor concentration by 5.0 and 6.9 times, respectively, for heptyl benzene and 2-tridecanone. Still, both chemicals failed to show increased detection for 13 of the 21 participants. In addition, plots of experimentally measured and calculated eye irritation thresholds as a function of carbon chain length for each series indicated that, based on the trend, the concentration of the two cutoff homologs at 37 degrees C should have been high enough to allow detection. Taken together, the results suggest that these cutoffs rest on limitations related to the dimension of the molecules rather than on limitations related to their vapor concentration. For example, the stimulus molecule could exceed the size that allows it to fit into the receptor pocket of a receptive protein. Plots of calculated molecular dimensions across homologous alkylbenzenes, from ethyl to dodecylbenzene, and across 2-ketones, from 2-octanone to 2-octadecanone, provided additional support to the above conclusion. 相似文献
970.
Simbayi LC Kalichman SC Jooste S Mathiti V Cain D Cherry C 《Journal of studies on alcohol》2004,65(4):434-442
OBJECTIVE: To examine the association of alcohol use and sexual risks for HIV infection in South Africa. METHOD: 149 men and 78 women receiving sexually transmitted infection (STI) clinic services in Cape Town, South Africa, completed measures of demographic characteristics, sexual behaviors, HIV risk reduction skills and substance use, including global measures (e.g., Alcohol Use Disorders Identification Test [AUDIT]) and situational measures of alcohol use. RESULTS: 52% of men (n = 72) and 17% of women (n = 13) indicated problem drinking (AUDIT score > or = 9). Problem drinking was associated with greater numbers of sex partners in the past month, history of condom failures and lifetime history of having an STI, as well as lower rates of practicing risk reduction skills. In a separate analysis controlling for global use of alcohol indexed by AUDIT scores, we found that alcohol use in sexual contexts was associated with greater numbers of sex partners, higher rates of unprotected intercourse and condom failures. CONCLUSIONS: Findings from this initial study of alcohol use and sexual risks in South Africa parallel those from other countries in sub-Saharan Africa. Although limited to STI clinic patients, the results suggest that effective HIV risk reduction interventions will require attention to alcohol use, particularly among South Africans at highest risk for HIV infection. 相似文献