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排序方式: 共有451条查询结果,搜索用时 15 毫秒
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Fine needle aspiration biopsy of Hashimoto's thyroiditis. Sources of diagnostic error. 总被引:8,自引:0,他引:8
OBJECTIVE: To determine the accuracy of cytologic interpretation in the diagnosis of Hashimoto's thyroiditis (HT). STUDY DESIGN: At Ottawa Hospital from 1987 to 1994, 1,638 fine needle aspiration biopsies (FNABs) from thyroid were performed. HT was suggested in 184 FNAB samples taken from 157 patients. Of the 184 aspirates diagnosed with HT, 39 had corresponding surgical specimens taken from 31 patients. A retrospective review of these FNABs and surgical pathology slides formed the basis of this study. RESULTS: In 27 (69%) aspirates, HT was diagnosed on both the FNAB and surgical specimens. In 10 of 27 FNABs an associated lesion was not sampled by FNAB. In four of these 10 aspirates some of the cellular features of HT were misinterpreted, and the possibility of an associated neoplasm could not be ruled out. This resulted in four false positive diagnoses. In 12 (31%) FNABs from nine patients, the cytologic diagnosis of HT was not confirmed histologically. These cases included five Hürthle cell adenomas and one case each of follicular adenoma, nodular goiter, macrofollicular adenoma and malignant lymphoma. This resulted in five false negative diagnoses. CONCLUSION: These results support the value of FNAB in the diagnosis of HT. The presence of hyperplastic follicular cells on FNAB samples from HT may mimic a follicular neoplasm and result in a false positive interpretation. Adequate sampling of the thyroid is important, particularly when there is an associated lesion. The diagnosis of lymphocytic thyroiditis should not be made when only a few lymphocytes are present. Finally, pleomorphic Hürthle cells may be present in aspirates from Hürthle cell neoplasms and underdiagnosed as HT, especially when they are associated with a few lymphocytes. 相似文献
3.
H M Yazdi 《Acta cytologica》1987,31(3):340-344
The clinical and cytopathologic features of a case of ovarian sex cord tumor with annular tubules are presented. To the best of our knowledge, this is the first report describing the cytologic features in a fine needle aspirate. Aspiration cytology cannot distinguish this tumor with certainty from a granulosa-cell tumor. 相似文献
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Effects of Short-Term Over-supplementation of Copper in Milk on Hematology,Serum Proteins,Weight Gain,and Health in Dairy Calves 总被引:1,自引:0,他引:1
Zahra Naseri Mehrdad Mohri Mohammad R. Aslani Ali A. Alavi Tabatabaee 《Biological trace element research》2011,139(1):24-31
Thirty-six calves were used in the present study. The animals were divided equally into three groups (control, test 1, and
test 2). The three groups of calves were homogeneous for parity of dams, sex, and month of birth. From 14 days of age, in
the test 1 group copper as copper sulfate (Merck Co, Germany) was added to each meal of milk at a rate of 10 mg/kg of milk
for 14 days and in test 2 group copper as copper sulfate was added to each meal of milk at a rate of 20 mg/kg of milk for
14 days. Blood samples were taken by jugular venipuncture using disposable syringes at 14 (before Cu supplementation), 30,
60, and 80 days of age. Anticoagulated blood was used for CBC determination. Plane tubes were used for harvesting of serum
and the amounts of total serum protein, albumin, iron, and copper were measured. Calves were weighted at birth and at the
end of trial (day 80) and total gain and mean daily gain were calculated. Days of treatment for ill calves were also recorded
during experiment. Group (treatment) had no significant effect on the amounts of measured parameters except MCH values (p < 0.05) which were significantly lower in test 1 group than other trial groups. Age (sampling time) had significant effects
on the values of most measured parameters (p < 0.05) except WBC, lymphocyte, total protein, and fibrinogen. Significant interactions between sampling time and group were
not seen for any of measured parameters. No significant differences were seen for total weight gain and mean daily gain between
trial groups. Chi-square test revealed no significant difference for the days of treatment between trials groups. 相似文献
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Ghasem Ali Parad Mehrdad Zarafshar Gustavo Gabriel Striker Ali Sattarian 《Trees - Structure and Function》2013,27(5):1387-1393
European pear is a flooding-sensitive species, and for its cultivation in lowland areas, it is necessary to carry out the grafting of scions of commercial pear varieties into rootstocks belonging to flooding-tolerant wild pear species. Flooding tolerance of Pyrus boissieriana—a type of wild pear—was studied as a promissory rootstock for commercial pear. For this purpose, 3-month-old plants of P. boissieriana were subjected for 30 days to control (C), well-irrigated treatment, short-term (15 days) flooding plus 15 days recovery (F + R) and long-term (30 days) continuous flooding (F). Physiological performance, plant morphological changes and biomass accumulation were assessed. Results showed that, although stomatal conductance, transpiration and photosynthesis were progressively decreased by flooding, when flooding was short term (i.e., 2 weeks, F + R treatment) plants were able to adequately recover their physiological activity (50–74 % with respect to controls). In contrast, when plants continued to be flooded (F treatment), the physiological activity became null and the plants died quickly after the water subsided. Adventitious rooting was the most conspicuous registered morphological response to flooding, despite that flooded plants had shorter shoots and roots than control plants. Leaf and root biomass were 63 and 89 % higher under short-term flooding (F + R) than under continuous flooding (F), condition in which plants did not survive. In conclusion, P. boissieriana appears to be a promising species for its use as rootstock of commercial pear in lowland areas prone to flooding of up to 2 weeks. However, if the flooding period is extended, plants of this species are at risk of perishing. 相似文献
8.
Mojtaba Tabatabaei Yazdi Younes Ghasemi Abdollah Ghasemian Shadman Shokravi Hossein Niknahad Mohsen Amini Ali Dehshahri Mohammad Ali Faramarzi 《World journal of microbiology & biotechnology》2005,21(6-7):811-814
Summary The bioconversion of hydrocortisone by a locally isolated strain of cyanobacterium Fischerella ambigua PTCC 1635 was investigated. Fischerella ambigua had not been previously examined for this potential. The fermentation led to production of 11β,17α, 20β, 21-tetrahydroxypregn-4-en-3-one and 11β-hydroxyandrost-4-en-3,17-dione. The metabolites were isolated and purified by chromatographic methods and identified using
instrumental analyses. 相似文献
9.
Mojtaba Tabatabaei Yazdi Gholamreza Zarrini Elham Mohit Mohammad Ali Faramarzi Neda Setayesh Navid Sedighi Farzaneh Aziz Mohseni 《World journal of microbiology & biotechnology》2006,22(4):325-330
Summary One hundred and sixty-five strains of microorganisms with the ability to grow in a medium containing uric acid as a major
source of nitrogen were isolated from soil samples during a screening program. Among them, a zygomycete fungus with well-developed
columellae was recognized to produce high levels of the enzyme in a short time. Classification of the isolated fungus was
carried out according to the morphological and culture characteristics of the organism, and it was identified as Mucor hiemalis. The fungus was able to produce an intracellular urate oxidase in a fermentation medium mainly containing uric acid. Optimized
composition of the medium consisted of (l−1 of distilled water) uric acid, 7.0 g; maltose, 6.0 g; Vogel stock solution, 20 and 1 ml of 0.5 M copper sulphate. The optimum
pH and temperature for uricase production in the optimized medium were pH 6 and 30 °C, respectively. 相似文献
10.
Mehrdad Rajaei Iraj Saadat Mostafa Saadat 《Biochemical and biophysical research communications》2013,430(2):640-641
Polymorphism of variable number of tandem repeats (VNTR) in the promoter region of X-ray repair cross-complementing 5 (MIM: 194364, XRCC5; rs6147172) was reported. The aim of the present study is to evaluate the influence of this polymorphism on XRCC5 mRNA levels. Genotypes of XRCC5 VNTR were determined by high resolution of melting analysis (HRMA). The quantitative XRCC5 mRNA expression (compared to ß-actin expression) among 0R/1R, 1R/2R, and 1R/3R genotypes was investigated. There was a negative correlation between the overall number of tandem repeats and XRCC5 expression (r = ?0.965, df = 7, P < 0.001). The mRNA level of XRCC5 decreased as function of number of tandem repeats. The 3R allele of the VNTR polymorphism in the XRCC5 promoter region dramatically decreases the gene expression. 相似文献