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1.
Comparison of ThinPrep versus conventional smear cytopreparatory techniques for fine-needle aspiration specimens of head and neck masses. 总被引:2,自引:0,他引:2
Lloyd Ford Barry M Rasgon Raymond L Hilsinger Raul M Cruz Karen Axelsson Gregory J Rumore Thomas M Schmidtknecht Balaram Puligandla John Sawicki William Pshea 《Otolaryngology--head and neck surgery》2002,126(5):554-561
OBJECTIVES: Diagnostic accuracy of the ThinPrep process (Cytyc, Boxborough, MA) was compared with that of conventional (smear) cytopreparation for fine-needle aspiration (FNA) of head and neck masses. METHODS: In a prospective, randomized, single-blinded study, 209 patients served as their own controls and underwent 236 FNAs using ThinPrep and conventional (smear) cytopreparatory techniques. RESULTS: ThinPrep produced less air-drying artifact and less mechanical distortion than the conventional method. The conventional technique was diagnostic in 63% of samples; the ThinPrep technique was diagnostic in 55% of samples. When all results were combined, pathologists subjectively preferred the conventional technique but accepted use of ThinPrep as the only cytopreparatory technique for most head and neck masses. CONCLUSIONS: For adequately experienced cytopathologists, ThinPrep is acceptable for FNA of salivary masses, neck cysts, metastatic lymph nodes, and thyroid lesions. Conventional smear technique should be used for FNA of nonmetastatic lymphoid lesions. Use of ThinPrep can complement use of the conventional (smear) cytopreparatory technique when aspirate is nondiagnostic or bloody, when the patient has a blood-borne infectious disease, when the clinician is inexperienced, or when aspirate has entered the syringe. 相似文献
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目的由于卒中风险随着狭窄严重程度的增加而升高,因此认为颈内动脉(ICA)接近闭塞患者的卒中风险很高。在现有的随机试验中,还没有专门针对这种情况进行探讨,因此其处理尚存在争汶。方法:对相关文献进行系统评价。结果:对ICA接近闭塞患者的处理还存在争议:一些学者支持进行干预,而另一些学者则认为存在风险或没有益处而反对进行干预。在ICA接近闭塞的有症状患者中进行一项比较外科治疗与最佳内科治疗的多中心前瞻性随机试验似乎非常困难,因为这类研究需要大量的患者。尽管如此,基于目前的证据,似乎很难拒绝手术治疗。结论:由于目前对ICA接近闭塞患者的最佳处理方案仍存在着争议,因此需要前瞻性观察性研究以证实其在有症状和无症状人群中的患病率以及相关的卒中风险。基于目前的证据,大多数医疗中心选择手术治疗,但它相对干内科治疗的特粱尚右待证章. 相似文献
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Rupture of the distal biceps tendon: evaluation with MR imaging 总被引:2,自引:0,他引:2
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Influence of calcitonin treatment on the osteocalcin concentration in the algodystrophy of bone 总被引:1,自引:0,他引:1
A. Sawicki P. Szulc T. Sobczyk J. Goliszewski P. Garnier R. Labuszewski 《Clinical rheumatology》1992,11(3):346-350
Summary Algodystrophy (AD) attacks all tissues in the affected region and results in the rapid demineralization of bones. Osteocalcin (OC) and alkaline phosphatase (AP) are markers of bone turnover. Calcitonin is the treatment of choice of AD. Two groups of patients were studied: Group I (n=8)-acute stage of AD (before and during the calcitonin treatment), Group II (n=5)-late chronic stage of AD. In the acute stage of AD both OC level and AP activity were increased. They were normal in the chronic state of AD. During the calcitonin treatment OC level normalized after 14 days and then increased again. During the treatment, AP activity temporarily increased and then returned to the initial level. We confirm that an increased bone turnover is observed in the acute stage of AD. Discrepancy between OC level and AP activity reflects the local metabolic disturbances. Salmon calcitonin inhibits the algodystrophic process and probably contributes to the activation of the skeletal restoration. 相似文献
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Androgen receptor YAC transgenic mice carrying CAG 45 alleles show trinucleotide repeat instability 总被引:1,自引:15,他引:1
La Spada AR; Peterson KR; Meadows SA; McClain ME; Jeng G; Chmelar RS; Haugen HA; Chen K; Singer MJ; Moore D; Trask BJ; Fischbeck KH; Clegg CH; McKnight GS 《Human molecular genetics》1998,7(6):959-967
X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG
repeat expansion in the first exon of the androgen receptor (AR) gene.
Disease-associated alleles (37-66 CAGs) change in length when transmitted
from parents to offspring, with a significantly greater tendency to shift
size when inherited paternally. As transgenic mice carrying human AR cDNAs
with 45 and 66 CAG repeats do not display repeat instability, we attempted
to model trinucleotide repeat instability by generating transgenic mice
with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions
in their genomic context. Studies of independent lines of AR YAC transgenic
mice with CAG 45 alleles reveal intergenerational instability at an overall
rate of approximately 10%. We also find that the 45 CAG repeat tracts are
significantly more unstable with maternal transmission and as the
transmitting mother ages. Of all the CAG/CTG repeat transgenic mice
produced to date the AR YAC CAG 45 mice are unstable with the smallest
trinucleotide repeat mutations, suggesting that the length threshold for
repeat instability in the mouse may be lowered by including the appropriate
flanking human DNA sequences. By sequence-tagged site content analysis and
long range mapping we determined that one unstable transgenic line has
integrated an approximately 70 kb segment of the AR locus due to
fragmentation of the AR YAC. Identification of the cis - acting elements
that permit CAG tract instability and the trans -acting factors that
modulate repeat instability in the AR YAC CAG 45 mice may provide insights
into the molecular basis of trinucleotide repeat instability in humans.
相似文献
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