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801.
Thoracic fine needle aspiration biopsy versus fine needle cutting biopsy. A comparative study of 40 patients 总被引:1,自引:0,他引:1
The fine needle aspiration (FNA) biopsy findings were compared with the results of fine needle cutting (FNC) biopsy in 40 patients. The lesions (38 pulmonary nodules, 1 mediastinal mass and one lytic rib lesion) were biopsied with 22-gauge Greene and 21-gauge E-Z-EM needles through a 19-gauge needle guide. The FNA biopsy findings were based on smears and cell blocks of material obtained with the Greene needles while the FNC biopsy findings were based on tissue cores obtained by the E-Z-EM needles. In 83% of the cases, both techniques yielded specimens with similar cellularity; in seven cases, the FNA samples were more cellular. Malignancy was diagnosed in 80% of the patients: by both techniques in 26 patients, by FNA biopsy only in 5 patients and by FNC biopsy only in 1 patient. The sensitivity of FNA biopsy was higher than that of FNC biopsy (96.8% vs. 84.3%). The specificity and predictive value of positive results were 100% for both techniques. The predictive value of negative results was higher for FNA biopsy (88.8% vs. 54.5%). The majority of FNC biopsy tissue cores consisted mostly of clotted blood, lung tissue and/or fibrous tissue and did not facilitate or improve the diagnosis. Those data suggest that the contribution of FNC biopsy to the diagnosis of thoracic neoplasms is very limited and that the performance of FNC biopsy with an E-Z-EM needle in addition to or instead of FNA biopsy is not justified. 相似文献
802.
The ferret (Mustela putorius furo) is proving to be an excellent experimental animal for many anatomical and physiological studies of the adult and developing visual system. As a result, the amount of data available on the ferret's visual system is increasing at a rapid rate. The purposes of this paper are to briefly review some of those data and to present some of the reasons why the ferret is an appropriate choice as an experimental animal for visual system studies. 相似文献
803.
The zinc metalloendopeptidases EC 3.4.24.15 (EP24.15) and EC 3.4.24.16 (EP 24.16) are closely relatedubiquitous enzymes, which have well-defined in vitroactivities in generation and degradation of a range ofspecific peptide targets. Despite this, little is knownregarding their roles in whole animal physiology. One of thepeptides degraded by these enzymes in vitro isbradykinin, a mediator with potent effects on the vasculatureat both systemic and local levels. This review summarises thework that has examined the role of EP 24.15/24.16 inregulation of the vascular effects of bradykinin invivo. This work was made possible by the development of aspecific stable inhibitor of these enzymes, JA-2. Use of thisinhibitor has shown that EP 24.15/24.16 are capable ofregulating responses induced by exogenous bradykinin. Thiseffect was observed at a systemic level with an increase inthe hypotensive effect of intravenous bradykinin. Further workis required to determine whether these enzymes also regulatebradykinin produced endogenously. 相似文献
804.
Two culture systems for maintenance of Day 13-18 conceptus tissue were developed. Harvested culture media were assayed for luteotrophic activity by determining their ability to stimulate progesterone synthesis by dispersed bovine luteal cells. Significant luteotrophic activity was found in 80% of the 31 tissue culture media studied. A series of experiments carried out to determine the nature of the luteotrophic activity indicate that it is a small (Mr less than 10,000), heat-labile, lipid-soluble substance that is adsorbed by dextran-coated charcoal. The nature and activity of this factor, together with its synthesis by the early bovine conceptus, suggest that it may have a significant role in stimulating progesterone synthesis by the corpus luteum during early pregnancy. 相似文献
805.
Hickey William F. Stieber Anna Hogue-Angeletti Ruth Gonatas Jacqueline Gonatas Nicholas K. 《Brain Cell Biology》1983,12(5):751-766
Brain Cell Biology - Cells of the PC-12 rat pheochromocytoma cell line respond to nerve growth factor (NGF) by sprouting neurites and biochemically differentiating into sympathetic ganglion-like... 相似文献
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