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101.
Multihospital systems are an important and growing component in the health care delivery system in the United States. Because formalized marketing is relatively new in multihospital systems, the potential to increase the marketing productivity of member hospitals is great. The more is known about how these systems function, the more effective will be the public and private decision making involving these systems. To that end, the authors position marketing in multihospital systems as an innovative technology and examine comparative profiles of innovative and noninnovative multihospital systems. More innovative systems, scoring higher on the marketing innovation attribute index, are characterized by greater information systems and communication support, as well as a stronger commitment to the marketing function. Strategic implications and future research directions are explored. 相似文献
102.
Laparoscopic bipolar electrosurgical sterilization has been employed for nearly two decades. This bipolar procedure was intended to reduce the incidence of unintended complications, such as bowel burns. However, compared to the monopolar procedure, it produced a higher failure rate. This study examines the role of the low power-high voltage coagulation waveform on the effectiveness of electrosurgical desiccation on the rat uterine model of the fallopian tube. Desiccations were performed with both Kleppinger and Storz forceps using generator settings from 2 to 6. Desiccations performed to the visual endpoint (blanch, swell, and collapse) required from 23.8 to 30.0 joules, although procedures performed at a generator setting of 2 required long application times, an average 15.4 sec (Storz) and 28.2 (Kleppinger). All bipolar procedures led to a loss of tissue at the desiccation site at 12 weeks postsurgery. Therefore, the electrosurgical coagulation waveform proved to be effective in producing adequate in vivo tissue destruction even at very low generator settings. 相似文献
103.
104.
M J Tucker 《International journal of cancer. Journal international du cancer》1979,23(6):803-807
The effect of restricting food intake by approximately 20% was studied in rats and mice. Both species were fed as similar "natural" diet composed chiefly of cereals and bone meal. The duration of the rat study was 24 months, but mice were studied for their whole lifespan of 36 months. In the mice, restriction increased longevity, and in both species the incidence of tumours was reduced and the onset delayed. The effect upon the different types of tumour varied; some types appeared to be unaffected by restriction, but the most common types in each species, liver tumours in mice, pituitary, mammary and skin tumours in rats, were significantly reduced. 相似文献
105.
B. Tucker Woodson 《The Laryngoscope》1997,107(6):735-740
Uvulopalatopharyngoplasty (UPPP) is reported successful in treatment of obstructive sleep apnea for approximately 50% of patients. Several modifications of the procedure have been described, including transpalatal advancement pharyngoplasty, which resects a portion of posterior hard palate and advances the soft palate anteriorly. Comparing effectiveness of different techniques based on sleep and respiratory data is confounded by multiple variables including clinical failure at nonsurgical sites and imprecise patient selection techniques. Since pharyngeal surgical procedures prevent collapse and obstruction by structurally modifying the upper airway, measuring structural changes in size and collapsibility provides a method to compare techniques. To evaluate whether transpalatal advancement pharyngoplasty is more effective in modifying upper airway characteristics than UPPP, upper airway cross-sectional size and collapsibility were measured after UPPP and transpalatal advancement pharyngoplasty. Six patients were evaluated using a quantitative endoscopic technique. After transpalatal advancement pharyngoplasty maximal retropalatal airway size increased 321% from 29.7 ± 9.9 to 95.3 ± 16 mm2 (P < 0.01), and retropalatal closing pressure decreased from 4.7 ± 1.6 to -3.8 ± 0.7 cm/H2O (P < 0.01) compared with UPPP. Respiratory disturbance index decreased from 74.5 ± 13.5 to 29.2 ± 9 events/hour postoperatively (P < 0.05). Results support the conclusion that transpalatal advancement pharyngoplasty increases retropalatal size and decreases retropalatal collapsibility compared with UPPP. Since these characteristics are postulated to contribute to increased stability during sleep, transpalatal advancement pharyngoplasty may potentially improve UPPP outcome in selected patients with small retropalatal airway areas after traditional surgery. 相似文献
106.
Plasma vitamin B-12 concentrations relate to intake source in the Framingham Offspring study 总被引:1,自引:0,他引:1
Tucker KL Rich S Rosenberg I Jacques P Dallal G Wilson PW Selhub J 《The American journal of clinical nutrition》2000,71(2):514-522
BACKGROUND: Low vitamin B-12 status is prevalent among the elderly, but few studies have examined the association between vitamin B-12 status and intake. OBJECTIVE: We hypothesized that vitamin B-12 concentrations vary according to intake source. DESIGN: Plasma concentrations and dietary intakes were assessed cross-sectionally for 2999 subjects in the Framingham Offspring Study. The prevalence of vitamin B-12 concentrations <148, 185, and 258 pmol/L was examined by age group (26-49, 50-64, and 65-83 y), supplement use, and the following food intake sources: fortified breakfast cereal, dairy products, and meat. RESULTS: Thirty-nine percent of subjects had plasma vitamin B-12 concentrations <258 pmol/L, 17% had concentrations <185 pmol/L, and 9% had concentrations <148 pmol/L, with little difference between age groups. Supplement users were significantly less likely than non-supplement-users to have concentrations <185 pmol/L (8% compared with 20%, respectively). Among non-supplement-users, there were significant differences between those who consumed fortified cereal >4 times/wk (12%) and those who consumed no fortified cereal (23%) and between those in the highest and those in the lowest tertile of dairy intake (13% compared with 24%, respectively), but no significant differences by meat tertile. Regression of plasma vitamin B-12 on log of intake, by source, yielded significant slopes for each contributor adjusted for the others. For the total group, b = 40.6 for vitamin B-12 from vitamin supplements. Among non-supplement-users, b = 56.4 for dairy products, 35.2 for cereal, and 16.7 for meat. Only the meat slope differed significantly from the others. CONCLUSIONS: In contrast with previous reports, plasma vitamin B-12 concentrations were associated with vitamin B-12 intake. Use of supplements, fortified cereal, and milk appears to protect against lower concentrations. Further research is needed to investigate possible differences in bioavailability. 相似文献
107.
Second cancers after medulloblastoma: population-based results from the United States and Sweden 总被引:5,自引:0,他引:5
Alisa M. Goldstein Jonathan Yuen Margaret A. Tucker 《Cancer causes & control : CCC》1997,8(6):865-871
Medulloblastoma, one of the most common central nervous system(CNS)tumors in children, requires aggressive multimodality therapy
including surgery, radiation therapy, and occasionally chemotherapy. Given its intensive treatment regimen and improved survival
during the past 20 years, it is likely that a cohort of survivors will result who may incur consequences of therapy, including
a second cancer. We used population-based data from the United States and Sweden to estimate risks of second neo plasms in
patients with histologically confirmed medulloblastoma (n = 1,262).Overall, there was a 5.4-fold excess of second neoplasms
(95 percent confidence interval = 3.3-8.4) based on 20 observed and 3.7 expected cancers. The second cancers occurred eight
to 432 months after initial diagnosis(median, 73 months) with significantly elevated ratios for all intervals examined except
for less than one year after initial diagnosis. Significantly elevated risks were seen for cancers of the salivary glands,
cervix uteri, brain and CNS, thyroid gland, and acute lymphoblastic leukemia. Of the 15second cancers with treatment data,
seven occurred in the radiation field or within areas of scatter while two others may have been radiation-related. Although
based on small numbers of second cancers, the results suggest that as survival increases, some patients with medulloblastoma
will have an increased risk of a second cancer, particularly a radiation-related cancer. Thus, as survival improves, late-occurring
consequences of diagnosis and treatment will need to be carefully assessed. Identification of patients hypersensitive to radiation
therapy, such as those with Gorlin Syndrome, should also be attempted in order to reduce the sequelae from intensive radiation
exposure.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
108.
Sustainable maternity services in remote and rural Scotland? A qualitative survey of staff views on required skills, competencies and training
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J Tucker V Hundley A Kiger H Bryers J Caldow J Farmer F Harris J Ireland E van Teijlingen 《Quality in health care》2005,14(1):34-40
Objectives: To explore staff views on their roles, skills and training to deliver high quality and local intrapartum services in remote and rural settings against national recommendations. 相似文献
109.
Cancer Incidence in Kentucky, Pennsylvania, and West Virginia: Disparities in Appalachia 总被引:7,自引:0,他引:7
Eugene J. Lengerich VMD MS ; Thomas C. Tucker PhD MPH ; Raymond K. Powell MPH ; Pat Colsher PhD ; Erik Lehman MS ; Ann J. Ward MS ; Jennifer C. Siedlecki BS ; Stephen W. Wyatt DMD MPH 《The Journal of rural health》2005,21(1):39-47
CONTEXT: Composed of all or a portion of 13 states, Appalachia is a heterogeneous, economically disadvantaged region of the eastern United States. While mortality from cancer in Appalachia has previously been reported to be elevated, rates of cancer incidence in Appalachia remain unreported. PURPOSE: To estimate Appalachian cancer incidence by stage and site and to determine if incidence was greater than that in the United States. METHODS: Using 1994--1998 data from the central registries of Kentucky, Pennsylvania, and West Virginia, age-adjusted incidence rates were calculated for the rural and nonrural regions of Appalachia. These state rates were compared to rates from the Surveillance, Epidemiology, and End Results (SEER) program for the same years by calculating the adjusted rate ratio (RR) and a 95% confidence interval (CI). FINDINGS: Both the entire and rural Appalachian regions had an adjusted incidence rate for all cancer sites similar to the SEER rate (RR = 1.00 [95% CI, 1.00-1.01] and RR = 0.99 [95% CI, 0.99-1.00], respectively). However, incidence of cancer of the lung/ bronchus, colon, rectum, and cervix in Appalachia was significantly elevated (RR = 1.22 [95% CI, 1.20-1.23], 1.13 [95% CI, 1.11-1.14], 1.19 [95% CI, 1.16-1.22], and 1.12 [95% CI, 1.07-1.17], respectively). Incidence of cancer of the lung/bronchus and cervix in rural Appalachia was even more elevated (RR = 1.34 [95% CI, 1.31-1.36] and 1.29 [95% CI, 1.21-1.38], respectively). Incidence of unstaged disease for all cancer sites in Appalachia (RR = 1.06 [95% CI, 1.05-1.08]), particularly rural Appalachia (RR = 1.28 [95%CI, 1.25-1.301), was elevated. CONCLUSIONS: Cancer incidence in Appalachia was not found to be elevated. However, incidence of cancer of the lung/bronchus, colon, rectum, and cervix was elevated in Appalachia. The rates of unstaged cancer of every examined site were elevated in rural Appalachia, suggesting a lack of access to cancer health care. 相似文献
110.
Werner E Bischoff Stefano Bassetti Barbara A Bassetti-Wyss Michelle L Wallis Brian K Tucker Beth A Reboussin Ralph B D'Agostino Michael A Pfaller Jack M Gwaltney Robert J Sherertz 《Infection control and hospital epidemiology》2004,25(6):504-511
OBJECTIVE: To investigate whether rhinovirus infection leads to increased airborne dispersal of coagulase-negative staphylococci (CoNS). DESIGN: Prospective nonrandomized intervention trial. SETTING: Wake Forest University School of Medicine, Winston-Salem, North Carolina. PARTICIPANTS: Twelve nasal Staphylococcus aureus-CoNS carriers among 685 students screened for S. aureus nasal carriage. INTERVENTIONS: Participants were studied for airborne dispersal of CoNS in a chamber under three conditions (street clothes, sterile gown with a mask, and sterile gown without a mask). After 2 days of pre-exposure measurements, volunteers were inoculated with a rhinovirus and observed for 14 days. Daily quantitative nasal and skin cultures for CoNS and nasal cultures for rhinovirus were performed. In addition, assessment of cold symptoms was performed daily, mucous samples were collected, and serum titers before and after rhinovirus inoculation were obtained. Sneezing, coughing, and talking events were recorded during chamber sessions. RESULTS: All participants had at least one nasal wash positive for rhinovirus and 10 developed a symptomatic cold. Postexposure, there was a twofold increase in airborne CoNS (P = .0004), peaking at day 12. CoNS dispersal was reduced by wearing a gown (57% reduction, P < .0001), but not a mask (P = .7). Nasal and skin CoNS colonization increased after rhinovirus infection (P < .05). CONCLUSIONS: We believe this is the first demonstration that a viral pathogen in the upper airways can increase airborne dispersal of CoNS in nasal S. aureus carriers. Gowns, gloves, and caps had a protective effect, whereas wearing a mask did not further reduce airborne spread. 相似文献