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1.
National intercomparisons of activity measurements of 131I, a radioisotope widely used for diagnosis and therapy of thyroid related ailments, were initiated in 1979 as a quality assurance program, towards improving radiation safety procedures and related dosimetry in Nuclear Medicine Centres (NMCs) in India. Oral administration of a known quantity of radioiodine to patients requires accurate radioactivity measurements to be performed on a well-calibrated isotope calibrators. Under or over estimation of the activity due to a faulty or uncalibrated isotope calibrator could provide misleading results. Calibration of isotope calibrators and the traceablity of subsequent measurements to the national standards laboratory is one of the essential basic radiation safety requirement of the IAEA. In view of the stringent quality assurance requirements for activity measurements imposed by Atomic Energy Regulatory Board, a National Intercomparison Program was initiated and to date ten such intercomparison programs have been conducted by the Radiation Safety Systems Division, of the Bhabha Atomic Research Centre. This program has benefited the participants by making their measurements traceable to the National Primary Standards. Over the years there has been a marked increase in the number of NMCs participating in the intercomparison programs. As a result, the number of institution showing large deviation from the correct value has decreased considerably over the years. This program thus, has enabled participating NMCs to check their isotope calibrators so as to ensure proper delivery of radiation dose to the patients and hence to optimise patient exposure.  相似文献   
2.
Acute airway distress due to thyroid pathology   总被引:3,自引:0,他引:3  
A Shaha  A Alfonso  B M Jaffe 《Surgery》1987,102(6):1068-1074
Patients with multinodular goiter or related thyroid disorders rarely have acute airway distress due to tracheal deviation or compression. However, our institution cares for a large number of patients with untreated multinodular goiters, and in the progression of this disorder, tracheal deviation and airway problems are relatively common. During the past 4 years, we have cared for 24 patients who were admitted with acute, life-threatening airway distress that required emergency intervention. Nine patients had emergency intubation, the remaining 15 had stridor on admission and underwent emergency operations. The series consists of 19 females and five males whose ages ranged from 37 to 89 years. Only four patients had malignant thyroid lesions (two papillary-follicular, two anaplastic), and two of these had multiple pulmonary metastases. Fifteen of the patients with multinodular goiters had a mediastinal extension that led to marked tracheal deviation. Three patients had recurrent multinodular goiters decades after previous surgery. Twenty-one patients underwent surgery at our institution, and all did well. Only one patient required sternotomy for thyroidectomy. Two patients required tracheostomy procedures, one because of tracheomalacia and the other because of poor pulmonary reserve. Interestingly, two patients had acute symptoms when in their third trimester of pregnancy. We have routinely used the laryngoscope (fiberoptic rigid or flexible) for preoperative and postoperative evaluation of the vocal cords and for determination of the condition of the larynx. On the basis of our experience with acute airway distress, we strongly advocate elective surgery for patients with multinodular goiter at the first sign of tracheal compression, especially if they have mediastinal extension.  相似文献   
3.

29. Tagung der ?sterreichischen Gesellschaft für Chirurgie und Ihrer Assoziierten Fachgesellschaften Innsbruck, 2. bis 4. Juni 1988 Herausgeber: E. Bodner und G. Szinicz Abstracts

Der chirurgische Part im Rahmen multimodaler Therapiekonzepte in der Onkologie-Schilddrüse  相似文献   
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PURPOSE: The goal of this study was to identify chromosomal aberrations associated with poor outcome in patients with head and neck squamous cell carcinoma (HNSCC). PATIENTS AND METHODS: We assessed the global genomic composition of 82 HNSCCs from previously untreated patients with comparative genomic hybridization (CGH). The CGH data were subcategorized into individual cytogenetic bands. Only genomic aberrations occurring in more than 5% of cases were analyzed, and redundancies were eliminated. Each aberration was submitted to univariate analysis to assess its relationship with disease-specific survival (DSS). We used Monte Carlo simulations (MCS) to adjust P values for the log-rank approximate chi(2) statistics for each abnormality and further applied the Hochberg-Benjamini procedure to adjust the P values for multiple testing of the large number of abnormalities. We then submitted abnormalities whose univariate tests resulted in an adjusted P value of less than.15 together with significant demographic/clinical variables to stepwise Cox proportional hazards regression. We again verified and adjusted P values for the chi(2) approximation of the final model by MCS. RESULTS: CGH analysis revealed a recurrent pattern of chromosomal aberrations typical for HNSCC. Univariate analysis revealed 38 abnormalities that were correlated with DSS. After controlling for multiple comparisons and confounding effects of stage, five chromosomal aberrations were significantly associated with outcome, including amplification at 11q13, gain of 12q24, and losses at 5q11, 6q14, and 21q11 (MCS adjusted P =.0009 to P =.01). CONCLUSION: HNSCC contains a complex pattern of chromosomal aberrations. A sequential approach to control for multiple comparisons and effect of confounding variables allows the identification of clinically relevant aberrations. The significance of each individual abnormality merits further consideration.  相似文献   
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7.

Background and Aim:

Central corneal thickness (CCT) of term and preterm infants in Indian population is not known. We did a prospective noninterventional study to measure the CCT in term and preterm infants.

Materials and Methods:

An ultrasonic pachymeter was used. The data regarding the date of birth, expected date of delivery, birth weight were recorded. The preterm and the term infants were followed up at 8 weeks, 20 weeks and at 1-year.

Results:

A total of 85 (170 eyes) children were included in the study. The mean age was 264.6 ± 21.8 days postconception. The mean birth weight and CCT were 1834.4 ± 512.1 g and 595.8 ± 72.4 μ respectively. A comparison of CCT on the basis postgestational age showed a mean thickness of 620.7 ± 88.8 and 574.4 ± 78.3 μ in the <260 days and >260 days age groups respectively. The difference was statistically significant (Student''s test, P = 0.002). The CCT of preterm infants (<260 days) decreased from a mean value of 620.7 ± 88.8 μ to 534.1 ± 57.6 μ at the end of 1-year.

Conclusion:

We present the data of CCT in term and preterm infants in Indian population. We believe that the premature babies have slightly thicker corneas than mature term babies.  相似文献   
8.
The serum thyroglobulin (Tg) level is the most sensitive marker for detecting residual thyroid carcinoma. We hypothesized that the basal and TSH-stimulated Tg levels in patients with metastatic thyroid carcinoma would reflect tumor volume, histological subtype, and location of metastatic lesions. A retrospective review of 417 thyroid cancer survivors undergoing evaluation for residual disease with the assistance of recombinant human TSH (rhTSH) was performed. In 169 patients with metastatic disease, we found that the basal Tg level directly correlated with the number of lesions, and that it was highest in patients with follicular and lowest in those with papillary thyroid carcinoma. The basal Tg level was highest in patients with bone metastases and lowest in those with cervical metastases. The fold increase in the serum Tg after rhTSH treatment was highest in papillary thyroid carcinoma and lowest in Hurthle cell carcinoma. The fold increase in Tg was not influenced by tumor volume or by the site of metastatic lesions. Multivariate analysis showed multiple interactions between factors, but did not identify one factor that significantly influenced basal Tg or fold increase. We conclude that the location and volume of metastases influence basal Tg, but not its responsiveness to rhTSH, whereas the histological type of carcinoma influences both basal Tg and responsiveness to rhTSH.  相似文献   
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Neck dissection for papillary thyroid carcinoma (PTC) is the standard of care for patients with clinical evidence of regional metastases. However, the extent of neck dissection is debatable. The purpose of the current study was to develop evidence‐based recommendations for when to include level V, or 1 of its sublevels, among patients with PTC undergoing neck dissection. A literature review of all studies evaluating the occurrence of metastases in level V in patients with regional metastases from PTC undergoing neck dissection was performed. Occurrence of metastases at level V is low in most series (5% to 10%), although a wide range was noticed. In cases in which metastases were found at level V, they occurred almost exclusively at sublevel VB. Sublevel VA was rarely, if ever, involved with metastatic lymph nodes. However, only recently have investigators begun to specify which sublevels of level V are at risk. Therapeutic dissection of level V is indicated when there is clinical evidence of disease involving this zone. Elective dissection of sublevel VB is indicated when there is involvement of level IV, or possibly multiple nodes at levels II and III. Under these circumstances, dissection of sublevel VB is indicated but sublevel VA may be spared. © 2012 Wiley Periodicals, Inc. Head Neck, 2013  相似文献   
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