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51.
52.
Investigation of thyroid, head, and neck cancers with PET   总被引:2,自引:0,他引:2  
PET with [(18)F]-fluorodeoxyglucose (FDG) has been accepted as a useful imaging modality for the diagnosis of a variety of malignancies. This article discusses the use of FDG-PET in the management of patients with thyroid and head or neck cancers.  相似文献   
53.
OBJECTIVE: To evaluate the effect of body mass index (BMI) on clinical/pathologic features, surgical morbidity, and outcome in patients with endometrial cancer. METHODS: All women with surgically treated endometrial cancer at the University of Washington in Seattle, Washington, between 1 January 1990 and 1 January 2000 were eligible; 439 patients were identified and 43 were excluded due to incomplete medical records; 396 patients underwent retrospective chart review. Statistical analysis was performed by SPSS. Median follow-up time was 27 months (range, 1 to 120 mo). RESULTS: Mean BMI was 34 (range, 15 to 69). BMI was <30 in 40.7% of patients, 30 to 40 in 32.3%, and >40 in 27.0%. Clinically, patients with a BMI of >40 were more likely to have hypertension, diabetes, and pulmonary disease. Those patients with a BMI of >40 had statistically longer operating times (209 vs. 159 min) and more blood loss (604 vs. 324 ml) than patients with a BMI of <30. However, there was no difference between the three groups in number of lymph nodes removed, units of blood transfused, length of hospital stay, number of intensive care unit (ICU) days, or intraoperative complications. Postoperatively, patients with a BMI of >40 were more likely to have a wound separation than thinner patients. Pathologically, patients with a BMI of >40 were more likely to have endometrioid histology, lower stage disease, and lower grade tumors than women with a BMI of <30. However, 11.3% of patients with lymph node sampling and a BMI of >40 had positive lymph nodes and 23% were stage II or higher. Forty-two patients (10.6%) recurred. There were no postoperative deaths, and there was no difference in survival between the three groups. CONCLUSIONS: Patients with a BMI of >40 frequently have favorable stage I endometrial cancers. However, approximately a quarter of these patients have evidence of cervical or extrauterine disease. This study confirms that surgical staging can be performed adequately and safely in morbidly obese patients with no difference in length of hospital stay, number of ICU days, intraoperative or postoperative complications.  相似文献   
54.
OBJECTIVE: This study was undertaken to estimate the reliability and validity of an objective structured assessment of technical skills (OSATS) for midline episiotomy repair using a lifelike anatomic model. STUDY DESIGN: Eighteen residents were administered an episiotomy OSATS. Two evaluators independently completed an objective score sheet assessing six key components of the repair, seven global surgical skills, and a pass/fail score for each resident. Residents also completed an anonymous self-assessment. RESULTS: Reliability indices were 0.95 for the checklist and global surgical skills rating. Construct validity found significant differences on the checklist, global surgical skills, and pass/fail score sheets by residency level. Residents more often assessed their own global surgical skills performance lower than the independent evaluators. Surprisingly, 61% (11/18) of the residents failed the assessment, including all postgraduate year 1 and postgraduate year 2 residents. CONCLUSION: Episiotomy OSATS that used task-specific and global checklists provide a reliable and valid method of assessing resident skills in this anatomic model, and performance correlates with resident year level of training.  相似文献   
55.
OBJECTIVE: This study was undertaken to evaluate whether the absolute nucleated red blood cell (RBC) count is elevated in term, appropriate-for-gestational-age (AGA) polycythemic infants. STUDY DESIGN: We compared absolute nucleated RBC counts taken during the first 12 hours of life in term, AGA infants with neonatal polycythemia (n = 29), and in control, nonpolycythemic infants (n = 37). We excluded infants of women with diabetes, hypertension, and alcohol, tobacco, or drug abuse, and those with fetal heart rate abnormalities or low Apgar scores, hemolysis, blood loss, or chromosomal anomalies. RESULTS: There were no differences between groups in birth weight, gestational age, or other demographic or perinatal factors. The hematocrit, RBC count, and absolute nucleated RBC counts were significantly higher and the platelet counts significantly lower in the polycythemic group. Regression analysis that included Apgar scores and gestational age showed a significant correlation of absolute nucleated RBC count with the polycythemia status only (P =.017). CONCLUSION: At birth, term AGA polycythemic infants have increased indices of active erythropoiesis. We speculate that this finding is suggestive of subtle fetal hypoxemia.  相似文献   
56.
Bone ultrasound velocity curves of newly born term and preterm infants   总被引:6,自引:0,他引:6  
BACKGROUND: Ultrasound velocity (speed-of-sound [SOS]) has been proposed as a non-invasive method of evaluation of bone status in infants. We hypothesized that SOS correlates with both gestational age and birth weight. METHODS: We measured SOS within the first 96 hours of life at the right tibial midshaft location in 73 neonates ranging in gestational age from 25 to 41 weeks, and in birth weight from 825 to 3880 grams. We used the Sunlight Omnisense 7000p device (Tel Aviv, Israel). Results are expressed as meanS +/- 1 SD; statistical analyses included linear regression and computation of 95% CI regression lines; p<0.05 was considered significant. RESULTS: There was, as hypothesized, a significant correlation between gestational age (or birth weight) and SOS. There were no significant differences between males and females. Ninety-five percent confidence intervals were established. CONCLUSIONS: These data may be used as reference ranges for further studies.  相似文献   
57.
Glial cell line-derived neurotrophic factor (GDNF) has shown potential as a treatment for Parkinson's disease. Recombinant adeno-associated viral vectors expressing the GDNF protein (rAAV-GDNF) have been used in rodent models of Parkinson's disease to promote functional regeneration after 6-OHDA lesions of the nigrostriatal system. The goal of the present study was to assess the anatomical and functional efficacy of rAAV-GDNF in the common marmoset monkey (Callithrix jacchus). rAAV-GDNF was injected into the striatum and substantia nigra 4 weeks prior to a unilateral 6-OHDA lesion of the nigrostriatal bundle. Forty percent of the dopamine cells in the lesioned substantia nigra of the rAAV-GDNF-treated monkeys survived, compared with 21% in the untreated monkeys. Fine dopaminergic fibres were observed microscopically in the injected striatum of some rAAV-GDNF-treated monkeys, suggesting that rAAV-GDNF treatment may have prevented, at least in part, the loss of dopaminergic innervation of the striatum. Protection of dopamine cells and striatal fibre innervation was associated with amelioration of the lesion-induced behavioural deficits. rAAV-GDNF-treated monkeys showed partial or complete protection not only in the amphetamine and apomorphine rotation but also in head position and the parkinsonian disability rating scale. Therefore, our study provides evidence for the behavioural and anatomical efficacy of GDNF delivered via an rAAV vector as a possible treatment for Parkinson's disease.  相似文献   
58.
59.
To explore the role of brain-derived neurotrophic factor for survival and generation of striatal neurons after stroke, recombinant adeno-associated viral vectors carrying brain-derived neurotrophic factor or green fluorescent protein genes were injected into right rat substantia nigra 4-5 weeks prior to 30 min ipsilateral of middle cerebral artery occlusion. The brain-derived neurotrophic factor-recombinant adeno-associated viral transduction markedly increased the production of brain-derived neurotrophic factor protein by nigral cells. Brain-derived neurotrophic factor was transported anterogradely to the striatum and released in biologically active form, as revealed by the hypertrophic response of striatal neuropeptide Y-positive interneurons. Animals transduced with brain-derived neurotrophic factor-recombinant adeno-associated virus also exhibited abnormalities in body posture and movements, including tilted body to the right, choreiform movements of left forelimb and head, and spontaneous, so-called 'barrel' rotation along their long axis. The continuous delivery of brain-derived neurotrophic factor had no effect on the survival of striatal projection neurons after stroke, but exaggerated the loss of cholinergic, and parvalbumin- and neuropeptide Y-positive, gamma-aminobutyric acid-ergic interneurons. The high brain-derived neurotrophic factor levels in the animals subjected to stroke also gave rise to an increased number of striatal cells expressing doublecortin, a marker for migrating neuroblasts, and cells double-labelled with the mitotic marker, 5-bromo-2'-deoxyuridine-5'monophosphate, and early neuronal (Hu) or striatal neuronal (Meis2) markers. Our findings indicate that long-term anterograde delivery of high levels of brain-derived neurotrophic factor increases the vulnerability of striatal interneurons to stroke-induced damage. Concomitantly, brain-derived neurotrophic factor potentiates the stroke-induced neurogenic response, at least at early stages.  相似文献   
60.
This analysis represents a 5-year update of our mortality study of 7075 PCB exposed capacitor workers that now includes 1654 deaths and 235,984 person-years of observation with follow-up through 1998. In hourly males and females the observed number of deaths from all-cancers and all-causes were similar to the expected numbers. In salaried males all-cause and all-cancer mortality were significantly below the expected. In salaried females, all-cause mortality was significantly below the expected and all-cancer mortality was below the expected, but not significantly. We again failed to find any significant excess mortality in the a priori cancers of concern or in any other cancers in the total cohort or in the highly exposed portion of the cohort. These results expand on our previous observations and as before the data fail to demonstrate any causal association between occupational PCB exposure and excess cancer mortality or any other causes of death.  相似文献   
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