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71.
WL Craig CR Ramsay S Fielding ZH Krukowski 《Annals of the Royal College of Surgeons of England》2014,96(6):466-474
Introduction
This study describes variability of treatment for differentiated thyroid cancer among thyroid surgeons, in the context of changing patterns of thyroid surgery in the UK.Methods
Hospital Episodes Statistics on thyroid operations between 1997 and 2012 were obtained for England. A survey comprising six scenarios of varying ‘risk’ was developed. Patient/tumour information was provided, with five risk stratified or non-risk stratified treatment options. The survey was distributed to UK surgical associations. Respondent demographics were categorised and responses analysed by assigned risk stratified preference.Results
From 1997 to 2012, the Hospital Episode Statistics data indicated there was a 55% increase in the annual number of thyroidectomies with a fivefold increase in otolaryngology procedures and a tripling of cancer operations. Of the surgical association members surveyed, 264 respondents reported a thyroid surgery practice. Management varied across and within the six scenarios, and was not related consistently to the level of risk. Associations were demonstrated between overall risk stratified preference and higher volume practice (>25 thyroidectomies per year) (p=0.011), fewer years of consultant practice (p=0.017) and multidisciplinary team participation (p=0.037). Logistic regression revealed fewer years of consultant practice (odds ratio [OR]: 0.96/year in practice, 95% confidence interval [CI]: 0.922–0.997, p=0.036) and caseload of >25/year (OR 1.92, 95% CI: 1.044–3.522, p=0.036) as independent predictors of risk stratified preference.Conclusions
There is a substantial contribution to thyroid surgery in the UK by otolaryngology surgeons. Adjusting management according to established case-based risk stratification is not widely applied. Higher caseload was associated with a preference for management tailored to individual risk. 相似文献72.
73.
Lymphokine-induced phagocytosis in angiocentric immunoproliferative lesions (AIL) and malignant lymphoma arising in AIL 总被引:1,自引:1,他引:1
A factor that augmented the phagocytosis of IgG-coated ox red blood cells by the human monocyte/macrophage line U937 was identified in cell culture supernatants from two of two patients with angiocentric peripheral T cell lymphomas, three of three patients with angiocentric immunoproliferative lesions that were not frankly malignant, and one of two patients with T lymphoblastic malignancies. The factor was not present in supernatants derived from 14 nonangiocentric peripheral T cell lymphomas of other histologic types nor in ten cases of B cell lymphoma and two cases of Hodgkin's disease. A similar factor was present in the supernatants of concanavalin A (Con A)-stimulated normal peripheral blood mononuclear cells and in the supernatants of IL-2- dependent T cell lines derived from normal peripheral blood. The factor had an apparent mol wt of greater than 50,000 daltons, was heat labile (100 degrees C for two minutes), and stable at pH 2.0. Its stimulation of phagocytosis was independent of any increase in number of Fc receptors. Thus, this factor is probably not gamma-interferon. This factor may play a pathogenetic role in the hemophagocytic syndromes associated with certain T cell malignancies and immunodeficient states. 相似文献
74.
Human red cells (RBCs) were collected in CPDA-1 and then freeze-dried in lyoprotective solution. The lyophilized RBCs were then stored at -20 degrees C for 7 days. At the end of the storage period, the lyophilized RBCs were rehydrated and washed in dextrose saline. The washed, reconstituted, lyophilized RBCs were resuspended in final wash solutions of ADSOL, CPDA-1, or a special additive solution containing glucose, citrate, phosphate, adenine, and mannitol, and then they were stored at 4 degrees C for an additional 7 days. The main purpose of this study was to determine whether human RBCs can be lyophilized in such a manner that normal metabolic, rheologic, and cellular properties are maintained during rehydration and subsequent storage in standard blood bank preservative solutions. Our results show that reconstituted, lyophilized RBCs maintained levels of ATP, 2,3 DPG, lactate, and cellular properties that are equal to or better than those in control nonlyophilized RBCs stored for a comparable period in CPDA-1. Reconstituted, lyophilized RBCs stored at 4 degrees C after rehydration also show better maintenance of ATP, 2,3 DPG, and lactate than do control RBCs stored in the same preservative solutions for comparable periods. 相似文献
75.
76.
77.
Digital and conventional chest images: observer performance with Film Digital Radiography System 总被引:5,自引:0,他引:5
The Film Digital Radiography System (FilmDRS) is a device with a laser optical film digitizer, 2,000 X 2,000 X 12-bit memory, and a 1,000-line video display. To evaluate the adequacy of this device for general radiography of the chest, four readers independently analyzed both radiographs and the corresponding video display of the digitized chest images of 150 patients, consisting of 100 images of abnormalities and 50 normal images. The overall results indicate equal sensitivity for the two systems. The FilmDRS, with interactive windowing, proved superior in the detection of hilar and mediastinal disease. X-ray film was superior in allowing detection of hyperlucent states. There was equivalent sensitivity for other disease categories. Superior specificity was achieved with conventional radiographs. 相似文献
78.
79.
Endothelial modulation and changes in endothelin pressor activity during hypoxia in the rat isolated perfused superior mesenteric arterial bed. 总被引:3,自引:3,他引:0
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1. The isolated superior mesenteric arterial bed of the rat, perfused with Krebs-Henseleit solution containing 10 microM indomethacin, was used to study the effects of reducing dissolved O2 tension on the pressor responses to endothelin-1, endothelin-3 and sarafotoxin S6b. The modulation of these responses by the endothelium was investigated by removing the intima with the detergent CHAPS and, for endothelin-1, by inhibiting nitric oxide production with N omega-nitro-L-arginine methyl ester (L-NAME). Comparison was made with the effects of lowering O2 tension on the pressor responses to noradrenaline and 5-hydroxytryptamine. 2. Lowering the perfusate O2 tension from 551 +/- 2 mmHg to 14.0 +/- 0.5 mmHg did not change the ED50 for endothelin-1 but its maximal responses (Rmax) were increased by 2.1 and 2.7 fold, respectively, in the presence and absence of endothelium. The Rmax values for endothelin-3 were also greater in hypoxia either in the presence (by 2.3 fold) or absence of the endothelium (by 1.6 times) but those for sarafotoxin S6b were only enhanced significantly by hypoxia in the absence of the intima. hypoxia reduced the potencies of endothelin-3 and sarafotoxin S6b whether or not endothelium was present. 3. Endothelial destruction, whether in hypoxic or oxygenated conditions, increased the Rmax values for endothelin-1 and endothelin-3; at both O2 tensions those for endothelin-3 increased more than those for endothelin-1. The ED50 for endothelin-1 was unchanged by destroying the endothelium but endothelin-3 was less potent in the absence of an endothelium than in its presence.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
80.
T M Keravis H Nehlig M F Delacroix D Regoli C R Hiley J C Stoclet 《European journal of pharmacology》1991,207(2):149-155
Bradykinin (BK) binding sites were studied in membranes from bovine aorta. [3H]BK specifically bound to one high-affinity binding site (KD = 152 pM; Bmax = 4.6 fmol.mg-1) and was displaced by unlabeled BK (Ki = 121 pM). The B2-agonist kallidin and B2-antagonists D-Arg0[Hyp3,Leu5,8,Gly6,D-Phe7]BK, D-Arg0[Hyp3,D-Phe7]BK, [D-Phe7]BK, and [Thi5,8,D-Phe7]BK inhibited [3H]BK binding with respective Ki values of 101, 282, 678, 2000 and 6000 pM. The B1-antagonist des-Arg9[Leu8]BK had no effect. GTP, GTP gamma S, GDP, and GDP beta S but not 5'-GMP, guanosine, cyclic 3',5'-GMP, ATP, ADP, 5'-AMP, nor adenosine, inhibited [3H]BK binding with an IC50 of 1-3 microM for GTP and GDP and an IC50 of 0.1-0.3 microM for GTP gamma S and GDP beta S. GTP and GDP at 3 microM decreased the Bmax value by 30-70%. Millimolar concentrations of Ca2+ and Mg2+ ions increased [3H]BK binding and counteracted the effect of guanine nucleotides. This study demonstrates the existence of a specific high-affinity B2 BK binding site in bovine aortic endothelial cells. It suggests that this site is located on a G protein-interacting receptor. 相似文献