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991.
To determine whether a natural plane of dissection occurs in the normal human vocal fold, semi-blunt instruments (Bouchayer laryngeal dissectors) were used to dissect the lamina propria. The depth of the plane of dissection was correlated with the elastin fibre concentration to determine whether the plane occurred at a predictable point in the elastin concentration as it increased between the superficial and middle layers. Eight human larynges were dissected using an operative microscope. The dissection plane consistently occurred between 23-50% depth into the lamina propria. No consistent correlation was found with the elastin fibre concentration. The depth of the plane of dissection has an interesting association with age: dissection planes occurred more superficially in older specimens.  相似文献   
992.
BACKGROUND: Velopharyngeal insufficiency is an uncommon complication of adenoidectomy. Persistent velopharyngeal insufficiency following adenoidectomy (VIA) may occur in association with an unrecognized syndrome, such as velocardiofacial syndrome (VCFS). Although the diagnosis of VCFS is primarily a clinical one, a test has been developed to identify the underlying chromosomal abnormality, ie, deletion of 22q11. OBJECTIVE: To describe characteristics and occurrence of the 22q11 deletion in a population with VIA. SETTING: Three tertiary referral centers. DESIGN: Retrospective case series of 23 patients with VIA who required intervention and had follow-up for more than 1 year. These patients' medical records were reviewed for indications for adenoidectomy, the presence of 22q11 deletion and whether a 22q11 deletion test was obtained, phenotypic evidence for VCFS, presence of a submucous cleft palate, velopharyngeal closure pattern, and type of speech intervention. RESULTS: Of the 23 patients, 9 underwent adenoidectomy for otitis media, 9 for obstructive sleep symptoms, and 5 for sinusitis therapy. Fourteen of the 23 patients were tested for a 22q11 deletion. Of these 14 patients, 9 had a 22q11 deletion with 5 having phenotypic evidence for VCFS. Six of the 23 patients had a submucous cleft palate, 2 of whom had a 22q11 deletion. CONCLUSIONS: Although VIA is uncommon, its occurrence should alert the otolaryngologist to the possibility of an underlying syndrome diagnosis. The 22q11 deletion test is beneficial in diagnosing patients with genotypic, but not phenotypic, VCFS in this population. In tested subjects of our patient population, 28% (4 patients) had the genotype for VCFS, without clinical evidence of VCFS.  相似文献   
993.
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995.
BACKGROUND: Registered dietitian/registered nurse (RD/RN) teams were created to place small bowel feeding tubes (SBFT) at the bedside in intensive care unit (ICU) patients using an electromagnetic tube placement device (ETPD). The primary objective of this study was to evaluate the safety of placing feeding tubes at the ICU bedside using an ETPD. Secondary outcomes included success rate, cost, and timeliness of feeding initiation. METHODS: Data were collected prospectively on 20 SBFT blind placements in ICU patients (control group). After implementing a protocol for RD/RN teams to place SBFTs with an ETPD, 81 SBFTs were placed (study group). Complications, success rate, number of x-rays after tube placement, x-ray cost, and time from physician order to initiation of feedings were compared between the groups. RESULTS: No adverse events occurred in either group. Successful SBFT placement was 63% (12/19) in the control group and 78% (63/81) in the study group (not significant, NS). The median time between physician order for tube placement and feeding initiation decreased from 22.3 hours (control group) to 7.8 hours (study group, p = .003). The median number of x-rays to confirm correct placement was 1 in the study group compared with 2 in the control group (p = .0001), resulting in a 50% decrease in the mean cost for x-rays. CONCLUSIONS: No adverse events occurred with the implementation of bedside feeding tube placement using an ETPD. In addition, SBFT placement with an ETPD by designated ICU RD/RN teams resulted in lower x-ray costs and more timely initiation of enteral feedings compared with blind placement.  相似文献   
996.
In Wales, a cancer genetics service has been developing since 1998. Gynaecologists play an integral role in the management of women with a family history of ovarian cancer and we were interested in investigating referral practice and management for relatives of patients with ovarian cancer among gynaecologists in Wales. In 1999, a postal questionnaire was sent to all gynaecologists. The response rate was 51%. The questionnaire contained structured questions about current provision and a number of hypothetical scenarios to explore referral patterns to the cancer genetics service. The results of this study showed that referrals varied widely among specialists, as did the numbers who required onward referral to cancer genetics. The offer of screening to women at high risk of ovarian cancer was consistent, although there were variations in how often it was offered and the age at which it was offered. Most gynaecologists were easily able to establish when it was appropriate to refer onwards to cancer genetics, differentiating between women at high or low risk. There was some confusion about women at moderate risk of ovarian cancer. This study demonstrated the need for clear referral guidelines in Wales. Guidelines have since been distributed to all general practitioners and specialists; however, continued monitoring and further evaluation of referral practices will be necessary.  相似文献   
997.
Histologic evaluation and reporting of invasive breast cancer has effectively used Nottingham combined histologic grade (NCHG). This approach to predict outcome in invasive breast cancer has not been tested in multicenter cooperative trials. Histologic slides from selected breast cancer cases entered on node-negative Eastern Cooperative Oncology Group trials were assigned grades. Two pathologists evaluated cases for NCHG defined from differentiation, mitotic index, and nuclear grade. The study population consisted of separate samples from low- and high-risk strata, where low risk was estrogen receptor positive with a tumor size of less than 3 cm and high risk was estrogen receptor negative or tumor size greater than or equal to 3 cm. The rate of agreement was generally good, with 80% of cases classified the same for mitotic count and 76% of the cases classified the same for combined grade. There were no cases disagreeing from the lowest to the highest of the three categories. The median follow-up is 11.6 years, but for analysis of survival, this was truncated at 5 years. Mitotic index and combined grade as assessed by both pathologists showed significant associations with survival. High combined histologic grade was predictive for response to cyclophosphamide/methotrexate/5-fluorouracil (CMF) with survival differences at 5 years of 30% in the treated high-grade patients over the untreated patients. Overall, it is clear that pathologists can have close agreement in assignment of combined histologic grades, with highly significant prediction in univariate and borderline significance in multivariate analysis in prognostication of time to recurrence as well as survival. Thus, stratification used in these trials was highly prognostic as hoped, leaving a role for histologic grading in these relatively large tumors, more powerful than S-phase analysis in this series. In the subgroups of high-risk patients randomized between CMF and observation, there was a suggestion that the high-combined-grade group was predictive of treatment efficacy. We conclude that a combined histologic grade with defined criteria may be reliably assigned by practiced pathologists using readily available criteria, and that the measure may be of use in prognostication and prediction of therapeutic responsiveness when done in a technically ideal fashion.  相似文献   
998.
PURPOSE/OBJECTIVES: To examine relationships between family primary caregiver characteristics and satisfaction with hospice care, quality of life (QOL), and burden. DESIGN: Exploratory, quantitative. SETTING: Five hospice organizations in Eastern Washington and Northern Idaho. SAMPLE: 44 primary caregivers of patients enrolled in hospice for more than two weeks. METHODS: Telephone surveys measured primary caregivers' satisfaction with hospice care, QOL, and burden. Demographic, personal, and situational characteristics were compiled. Multivariate regression techniques were used to identify caregiver characteristics that explained the most variation in satisfaction with hospice care, QOL, and burden. MAIN RESEARCH VARIABLES: Satisfaction with hospice care, QOL, and burden. FINDINGS: Being retired, being a wife or daughter, patient diagnosis, per diem rate paid to the hospice organization, county population and density, length of time in hospice, and length of time as a caregiver were significantly related to satisfaction with hospice care, QOL, and burden. Age, sex, education level, occupation, income, patient functional status, and social support were not related to these variables. CONCLUSION: Although caregivers reported satisfaction with hospice care, the caregiver role negatively affects their QOL and they are burdened. "At-risk" caregivers are still working, have been providing care for a long time, and live in a rural locale. IMPLICATIONS FOR NURSING PRACTICE: These findings create a profile of "typical" and "at-risk" primary caregivers and support the role of hospice to care for family caregivers.  相似文献   
999.
Lo TC  Beamis JF  Villanueva AG  Gray AW  Wu TR 《Clinical lung cancer》2001,3(1):65-8; discussion 69-70
Although the evolution from low-dose rate (LDR) to high-dose rate (HDR) brachytherapy for malignant endobronchial tumors was presumably based on economy, patient convenience, and radiation protection, our experience with both modalities permits assessment of the pros and cons of each technique. In November 1991, our HDR remote afterloading brachytherapy unit became operational. By that time, we had treated 110 patients (group 1) with malignant endobronchial obstruction with LDR brachytherapy. Since then, all patients have been treated with HDR brachytherapy. The outcome of our first 110 patients (group 2) treated with HDR brachytherapy is presented in this communication, using group 1 as the historic control group. In group 1, patients were treated with 1 or 2 sessions of 30-60 Gy, each calculated at a 1-cm radius. In group 2, patients received 3 or 4 weekly treatments of 7 Gy, each calculated at a 1-cm radius. The majority of patients in each group had previously received a full course of external beam irradiation, and a history of laser bronchoscopy was also similar for the 2 groups. Differences in bronchoscopic response rate (82% vs. 96%, respectively) and complications (3.6% vs. 2.7%, respectively) were statistically insignificant between the LDR group and the HDR group. We believe HDR brachytherapy is the state-of-the-art modality in intraluminal therapy for endobronchial malignancies.  相似文献   
1000.
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