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31.
Adenylate cyclase and guanylate cyclase activity in normal and leukemic human lymphocytes 总被引:1,自引:0,他引:1
Adenylate cyclase (AC) and guanylate cyclase (GC) activities were studied in normal B-enriched and T-enriched lymphocytes, in lymphocytes of children with acute lymphocytic leukemia (ALL), and in lymphocytes of adults with chronic lymphocytic leukemia (CLL). AC activity was greater in normal B than T lymphocytes (215 pmole/min/mg protein versus 80 pmole in the membrane-enriched fraction) and i both increased greatly after stimulation with isoproterenol and more so with prostaglandins E and F2 alpha. In leukemic lymphocytes, AC showed depressed activity (20 pmole in ALL cells and 55 pmole in CLL cells) and was less sensitive to hormonal stimulation: this loss of sensitivity occurred to a greater extent in ALL than in CLL lymphocytes. GC activity was greater in normal T than B cells (in membrane-enriched fraction: 10.2 pmole versus 5.3 pmole). It increased little with isoproterenol and prostaglandins stimulation, and much more with sodium azide and dehydroascorbic acid stimulation. GC activity was increased in both types of leukemic lymphocytes (23 pmole for ALL cells and 18 pmole for CLL cells) and was insensitive to stimulation. Possible derangement of cyclase and cyclic nucleotide regulation in leukemic cells is suggested. 相似文献
32.
Guillain-Barr啨综合征(GBS)和Miller Fisher综合征(MFS)的诊断标准随着临床研究的深入在不断演变。2011年1月,《疫苗》杂志发表了国际疫苗安全性监测Brighton合作组关于GBS/MFS的诊断定义和研究资料收集规范。此文献中未采用"诊断标准"而采用"诊断定义"是因为其主要目的为评价疫苗安全性而制定,而非用于神经科的GBS/ 相似文献
33.
AB Rossi JJ Leyden AS Pappert A Ramaswamy A Nkengne R Ramaswamy M Nighland 《Journal of the European Academy of Dermatology and Venereology》2011,25(4):398-402
Background Post‐inflammatory hyperpigmentation (PIH) is a common occurrence in patients with acne vulgaris, particularly in those with skin of colour. Aims A previous study has demonstrated the benefit of tretinoin (retinoic acid) in the treatment of PIH; however, there is currently no standard protocol to evaluate change in PIH following treatment. Based on these findings, we performed a pilot, exploratory, blinded, intraindividual‐controlled methodology study that consisted of a photographic assessment protocol with facial mapping. Materials and methods The study was based on a secondary analysis of a phase 4, community‐based trial of 544 acne patients who were treated with tretinoin gel microsphere 0.04% or 0.1%. Only patients with Fitzpatrick types III–V (skin of colour) were included in the study; subjects with Fitzpatrick skin type VI were excluded because the photographic assessment did not allow for proper evaluation. Results Despite the small number of subjects evaluated (n = 25), the results revealed consistent assessment of improvement in PIH between two independent graders (weighted κ = 0.84). Conclusion Further study with a larger population is recommended to validate the accuracy of this method. 相似文献
34.
Forty-three professional and amateur athletes with persistent shoulder pain that interfered with their sports activities were evaluated by computed tomographic (CT) arthrography. In 19 patients, glenohumeral instability (14 anterior, two posterior, three multidirectional) was diagnosed with CT arthrography based on the simultaneous presence of labral and capsular lesions. The findings were crucial in establishing the diagnosis of instability in six patients in whom the condition was not suggested or could not be confirmed clinically. Another significant injury consisted of labral lesions not associated with glenohumeral instability. These tears often involved the anterior and parasuperior segments of this structure. Other, less frequently detected lesions included segmental labral enlargement and several labra with abnormal orientation (everted labrum). Early onset of degenerative disease was present in many athletes, especially those with a long history of sports activity. CT arthrographic findings were correlated with arthroscopic or surgical results in 19 patients. 相似文献
35.
Rokey R; Verani MS; Bolli R; Kuo LC; Ford JJ; Wendt RE; Schneiders NJ; Bryan RN; Roberts R 《Radiology》1986,158(3):771-774
The feasibility of using magnetic resonance (MR) imaging to estimate myocardial infarct size was explored in an in vitro model using only the inherent differences in contrast between infarcted and noninfarcted myocardium. Eight dogs underwent coronary occlusion; their hearts were removed 6 hours later. Estimates of T2 for normal and infarcted myocardium were derived from MR images. Infarct size was quantified anatomically using triphenyltetrazolium-chloride (TTC) staining and compared with MR estimates. The T2 values derived from the images clearly discriminated between infarcted (126 +/- 22 msec) and normal myocardium (88 +/- 10 msec, P less than .05), providing images with good contrast between normal and infarcted myocardium. Comparable differences in T2 values were also noted from spectrometric determinations. Estimates of infarct size by MR imaging compared well with TTC estimates (r = 0.98) over a wide range of infarct sizes from 3% to 29% of the left ventricular mass. These results suggest the potential for in vivo quantification of infarct size based on the inherent contrast difference between infarcted and normal myocardium. 相似文献
36.
A dot-screen pattern was devised and superimposed on computed tomography images to improve contrast at a viewbox. The phenomenon is believed to be probably related to lateral inhibition. To evaluate its usefulness, the device was used on 12 images (eight showed metastatic liver lesions, and four were normal); each image was viewed without the device by ten observers. Three control images were viewed a second time without the device. The remaining nine images were viewed a second time with the device. The overlay improved diagnostic performance in nine observers. Sensitivity improved by 12%, and confidence in true-positive findings increased by 41.6%. Forty-five percent of false-negative findings were converted to true positive with the use of the overlay. 相似文献
37.
Zaeem Lone Prithvi B. Murthy JJ Haijing Zhang Kyle J. Ericson Lewis Thomas Abhinav Khanna Georges-Pascal Haber Byron H. Lee 《Urologic oncology》2021,39(5):301.e1-301.e9
PurposeRenal function outcomes following robot-assisted radical cystectomy (RARC) have not been well established. We sought to compare long-term renal function outcomes between open radical cystectomy, RARC with extracorporeal urinary diversion and intracorporeal urinary diversion at a high volume institution.Materials and MethodsWe retrospectively reviewed our institutional bladder cancer database for patients who underwent RC from 2010 to 2019 with pre-operative estimated glomerular filtration rate (eGFR) > 45 ml/min/1.73m2. Changes in renal function were assessed through locally weighted scatter plot smoothing and comparison of median eGFR between surgical groups. Chronic Kidney Disease Stage 3B was defined as eGFR < 45 ml/min/1.73m2. Renal function decline was defined as a ≥10 ml/min/1.73m2 drop in eGFR. Kaplan Meier method with log-rank was used to compare CKD 3B-free survival and renal function decline. Cox Proportional Hazards model was used to identify predictors of CKD 3B.ResultsSix hundred and forty four patients were included with median follow-up of 32 months (IQR 12–56). Preoperative characteristics were similar among the groups with no differences in median pre-operative eGFR (ORC: 74.6, extracorporeal urinary diversion: 74.3, intracorporeal urinary diversion: 71.6 ml/min/1.73m2, P = 0.15). Median postoperative eGFR on follow up was not different between groups (P = 0.56). 33% of patients developed CKD 3B. There were no differences in CKD 3B-free survival by surgical approach (P = 0.23) or urinary diversion (P = 0.09). 64% of patients experienced renal function decline with a median time of 2.4 years (P 0.23). Predictors of CKD were pathologic T3 disease or greater (HR: 1.77, P = 0.01), ureteroenteric anastomotic stricture (HR: 2.80, P < 0.001), preoperative CKD Stage 2 (HR: 1.81, P =0.02), and preoperative CKD Stage 3A (HR: 5.56, P < 0.001).ConclusionRenal function decline is common after RC. Tumor stage, pre-operative eGFR, and ureteral stricture development, not surgical approach, influence renal function decline. 相似文献
38.
L Jones J Moir C Brown R Williams JJ French 《Annals of the Royal College of Surgeons of England》2014,96(6):e1-e3
A 61-year-old man presented with jaundice, and subsequently underwent an extended left hepatectomy and pancreaticoduodenectomy for a cholangiocarcinoma invading the head of the pancreas. The patient developed sepsis due to a biliary leak at the hepaticojejunostomy. We describe the original use of a biodegradable stent, deployed via percutaneous transhepatic cholangiography into the Roux limb, resulting in good drainage and resolution of sepsis. The chief benefit of this procedure is the lack of need for subsequent removal as well as purported reduced biofilm accumulation. We believe this to be the first reported case of this type and the literature surrounding the subject is also discussed. 相似文献
39.
Background
Management of high-grade T1 (formerly T1G3) bladder cancer continues to be controversial. Should patients with T1G3 bladder cancer have an immediate radical cystectomy or should they receive intravesical bacillus Calmette-Guérin preserving bladder? Gemcitabine and cisplatin (GC) adjuvant chemotherapy may help to strike a balance between intravesical and early cystectomy. For purposes of this study, we continue to refer high-grade T1 lesion as “T1G3.”Objective
To evaluate the characteristics and the long-term outcome of GC adjuvant chemotherapy in T1G3 bladder cancer after transurethral resection of bladder tumor (TURBT).Materials and methods
We, retrospectively, reviewed 48 patients who were newly diagnosed with T1G3 bladder cancer between January 2009 and December 2012. A total of 48 patients received 4 cycles of GC adjuvant chemotherapy after TURBT. One month after 4 cycles of GC adjuvant chemotherapy, response was evaluated by re-TURBT. Median follow-up was 59.5 (range: 18–70) months, all patients have been observed for more than 3 years. Salvage cystectomy was recommended for patients with persistent disease and for tumor progression after initial complete response.Result
Complete response was achieved in 44 (91.7%) patients. Of complete responders, 5 patients experienced recurrence and 5 patients showed progression. The progression rate and disease-specific survival rate were 10.4% and 91.7% at 3 years, respectively. More than 80% of survivors preserved their bladder. Kaplan-Meier curves showed that concomitant carcinoma in situ (CIS) was the only factor that had an influence on progression-free survival (P = 0.022) and disease-specific survival (P = 0.017). Concomitant CIS was the prognostic factor for progression rate and disease-specific survival rate at 3 years (P = 0.008 and P = 0.035).Conclusion
GC adjuvant chemotherapy is a safe conservative treatment for T1G3 bladder cancer, but effective is really a phase II study. Patients with T1G3 bladder cancer with concomitant CIS should be treated more aggressively because of the high risk of progression. 相似文献40.