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91.
William G. Myers Rodney E. Bigler Richard S. Benua Martin C. Graham John S. Laughlin 《European journal of nuclear medicine and molecular imaging》1983,8(9):381-384
The first commercial version of the Massachusetts General Hospital (MGH) positron camera was used to image the relative distributions of 13N (T 1/2=9.96min) in the human heart, pancreas, and liver after intravenous administration of [13N]-l-glutamate. The instrument was operated in two imaging modes. Conventional 2-dimensional (2-D) focal-plane images showed high concentrations of 13N in the heart and pancreas, and lower levels in the liver. Five PET tomographic transverse section (3-D) images were made through the heart and three through the pancreas. Our results suggest that further studies designed to gain an improved understanding of the biochemistry of [13N]-l-glutamate aided by PET imaging, especially with newer instrumentation, are worthy of further investigation. 相似文献
92.
From 1985 to 1988, a state-wide program of cancer education was offered to community-based allied health professionals (AHPs) at five different program sites in Pennsylvania. During this three-year period, 512 social workers, clergy, dieticians, physical therapists and others received training to increase their knowledge about cancer and counseling, improve their supportive attitude regarding cancer patients and families, and decrease stress related to their work with this population. Overall, the Program was successful in reaching AHPs working with cancer clients who had little formal training in the cancer field. At the beginning of training, it was observed that AHPs with initially higher levels of education and more years of work experience with cancer patients had higher levels of counseling knowledge. Those who were women, worked in hospitals, or had worked with cancer patients longer exhibited higher levels of cancer knowledge. Participants who were women and who had more education had reported lower levels of job stress. Among those AHPs who completed the training courses, cancer knowledge increased by 14 percent. In addition, knowledge related to counseling cancer patients and their families improved by 11 percentage points. Perceived job stress among the AHPs also declined by 10 percent. Finally, participant supportive attitude concerning cancer clients improved. 相似文献
93.
The role and operation of transport in the health sector in developing countries is important, costly but often taken for granted. This article suggests the need for a fresh look at the policy, planning and management of transport through the analysis of the essential components of a successful transport scenario for health services in developing countries i.e. transport and health planning; transport and organisational responsibility; the role of health sector donors; decision-making and procurement of transport and spares; transport and human resources; monitoring and control of transport and information; maintenance and repair; the budget. The article concludes with a checklist of key questions that may be used in assessing the contribution of transport to the health services. 相似文献
94.
OBJECTIVE--To describe the magnitude and impact of the major biological and analytical sources of variation in serum lipid and lipoprotein levels on risk of coronary heart disease; to present a way to qualitatively estimate the total intraindividual variation; and to demonstrate how to determine the number of specimens required to estimate, with 95% confidence, the "true" underlying total cholesterol value in the serum of a patient. DATA SOURCES--Representative references on each source of variation were selected from more than 300 reviewed publications, most published within the past 5 years, to document current findings and concepts. Most articles reviewed were in English. STUDY SELECTIONS--Studies on biological sources of variation were selected using the following criteria: representative of published findings, clear statement of either significant or insignificant results, and acquisition of clinical and laboratory data under standardized conditions. Representative results for special populations such as women and children are reported when results differ from those of adult men. DATA EXTRACTION--References were selected based on acceptable experimental design and use of standardized laboratory lipid measurements. DATA SYNTHESIS--The lipid levels considered representative for a selected source of variation arose from quantitative measurements by a suitably standardized laboratory. Statistical analysis of data was examined to assure reliability. The proposed method of estimating the biological coefficient of variation must be considered to give qualitative results, because only two or three serial specimens are collected in most cases for the estimation. CONCLUSIONS--Concern has arisen about the magnitude, impact, and interpretation of preanalytical as well as analytical sources of variation on reported results of lipid measurements of an individual. Preanalytical sources of variation from behavioral, clinical, and sampling sources constitute about 60% of the total variation in a reported lipid measurement of an individual. A technique is presented to allow physicians to qualitatively estimate the intraindividual biological variation of a patient from the results of two or more specimens reported from a standardized laboratory and to determine whether additional specimens are needed to meet the National Cholesterol Education Program recommendation that the intraindividual serum total cholesterol coefficient of variation not exceed 5.0. A National Reference Method Network has been established to help solve analytical problems. 相似文献
95.
The "plateau effect" of cis-platinum-induced hearing loss 总被引:1,自引:0,他引:1
S F Myers B W Blakley S Schwan W F Rintelmann R H Mathog 《Otolaryngology--head and neck surgery》1991,104(1):122-127
Cis-platinum-induced hearing loss has been reported to exhibit a "plateau effect" over the 2 to 8 kHz range. We examined serial audiometry data from 27 patients treated with cis-platinum. Although a plateau at 60 to 70 dB HL often occurred, this hearing loss was clearly exceeded in a number of patients. We identified 14 patients with sufficient cis-platinum-induced sensorineural hearing loss to evaluate a plateau limit to hearing loss over the 4 to 8 kHz range. Half of these 14 patients had hearing losses that exceeded the plateau level. More severe 4 to 8 kHz hearing losses did not correlate with number of treatments, cumulative dosages of cis-platinum, pre-existing hearing loss, radiation therapy, other chemotherapeutic agents, or even hearing losses below 4 kHz. Although cis-platinum therapy can induce a plateau of moderate hearing impairment for some patients over the 4 to 8 kHz range, a significant proportion of patients will experience more severe hearing impairment in this range, even after only one or two courses of cis-platinum. 相似文献
96.
Factors which regulate net hepatic glucose uptake in vivo 总被引:1,自引:0,他引:1
A D Cherrington M J Pagliassotti S R Myers B Adkins-Marshall O P McGuinness 《JPEN. Journal of parenteral and enteral nutrition》1991,15(3):71S-73S
The regulation of net hepatic glucose uptake in vivo occurs by way of the hormonal milieu (insulin and glucagon), the glucose level, and the route of glucose delivery. Hyperglycemia in the absence of changes in pancreatic hormones (i.e., increased insulin and/or decreased glucagon) does not elicit significant glucose uptake by the liver. Net hepatic glucose uptake is augmented in a dose-dependent manner by a rise in insulin and is further stimulated by the presence of a "portal signal." The presence of coordinated changes in insulin, glucagon, and the glucose level in combination with the "portal signal" ensures adequate glucose uptake by the liver in response to a meal. 相似文献
97.
Esophagogastrectomy for adenocarcinoma of the cardia. Ten years' experience and current approach. 总被引:4,自引:2,他引:2 下载免费PDF全文
During a 10-year period, 94 surgical resections for adenocarcinoma of the cardia (75 "curative" and 19 palliative) were performed using three primary approaches: Group I (46 curative, 14 palliative), esophagogastrectomy performed through a left thoracotomy or left thoraco-abdominal incision; Group II (17 curative, 4 palliative), resection done through two separate incisions (abdominal and thoracic) with delayed reconstruction between two and three months later; and Group III (12 curative, 1 palliative), resection, also through abdominal and thoracic incisions, with simultaneous reconstruction. Operative mortality in the 75 procedures done for cure was 19.5%, 18%, and 8.3% in Groups I, II, and III, respectively. Microscopic residual tumor at the line of resection was 56%, 12%, and 8%. Free margins less than 3 cm had the same local recurrence rate (21%, 6%, and 8%) within 18 months as did margins with residual microscopic tumor. The length of time from operation to first regular meal was 12, 110, and 7 days, respectively. Wide resection with subtotal esophagectomy and simultaneous reconstruction is advocated. 相似文献
98.
99.
GA Smith SD Strausbaugh C Harbeck-Weber DM Cohen BJ Shields JD Powers 《Pediatrics》1997,100(5):825-830
OBJECTIVE: To compare the effectiveness of three new topical anesthetics that do not contain cocaine (prilocaine-phenylephrine, tetracaine-phenylephrine [tetraphen], and tetracaine-lidocaine-phenylephrine) to that of tetracaine-adrenaline-cocaine (TAC) during laceration repair in children. DESIGN: Prospective, randomized, double-blind clinical trial. SETTING: The emergency department of an urban children's hospital. PARTICIPANTS: Children 1 year of age or older with a laceration = 5 cm in length that required suturing. Intervention. A total of 240 children were randomly assigned to one of four treatment groups. OUTCOME MEASURES: Pain felt during suturing was scored by suture technicians, research assistants, parents, and patients >/= 5 years of age using a visual analogue scale (VAS). Suture technicians, research assistants, and parents also scored pain using a seven-point Likert scale. In addition, suture technicians completed an anesthetic effectiveness scale. RESULTS: There was consistently no difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. A statistically significant difference was seen among anesthetics when comparing VAS and Likert scale scores of suture technicians and Likert scale scores of research assistants. Based on post hoc analyses, these statistically significant differences were between TAC and prilocaine-phenylephrine (suture technician VAS and Likert scale) and between TAC and tetracaine-lidocaine-phenyl-ephrine (suture technician Likert scale), but not between TAC and tetraphen. When power analyses were performed using alpha = 0.05 and beta = 0.20, it was possible to detect a difference of 1.2 VAS units for each of the observer groups. Based on anesthetic effectiveness scale scores, the three new topical preparations collectively performed significantly better on the face and scalp than on the extremities (relative risk = 1.83; 95% confidence interval 1.20 < relative risk < 2.79). CONCLUSION: This study demonstrated the effectiveness and safety of three new non-cocaine-containing topical anesthetics. Consistently, there was no statistical difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. Tetraphen offers an effective alternative to TAC during laceration repair in children. 相似文献
100.