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41.
SURVEILLANCE CAN BE THE STANDARD OF CARE FOR STAGE I NONSEMINOMATOUS TESTICULAR TUMORS AND EVEN HIGH RISK PATIENTS 总被引:4,自引:0,他引:4
TON A. ROELEVELD SIMON HORENBLAS WIM MEINHARDT MARK van de VIJVER MARISKA KOOI WIM W. TEN BOKKEL HUININK 《The Journal of urology》2001,166(6):2166-2170
PURPOSE: We investigate the results of a surveillance program for stage I nonseminomatous germ cell tumors to validate a surveillance policy, and furthermore improve it by analyzing diagnostic instruments and identifying prognostic factors for relapse. MATERIALS AND METHODS: From 1982 to 1994, 90 patients with stage I nonseminomatous germ cell tumors entered a surveillance protocol after orchiectomy. Patients with relapse were treated with cisplatin based chemotherapy. A statistical analysis of possible prognostic factors for relapse was performed. RESULTS: Relapse occurred in 23 (26%) patients. Disease specific survival was 98.9%, and 1 patient died of tumor. Most relapses were located in retroperitoneal lymph nodes only (78%). Tumor markers were the most important indicators of relapse. However, in 22% of patients with relapse abdominal x-ray of lymphangiographic contrast showed the first sign of relapse. Computerized tomography located all but 1 relapse. Vascular invasion (p = 0.0001), tumor size (p = 0.0341) and presence of immature teratoma (p = 0.0154) were significantly predictive of relapse with the multivariate analysis, percentage embryonal carcinoma only by univariate analysis (p = 0.032). The relapse rate was highest (52%) when vascular invasion was present. CONCLUSIONS: With surveillance for stage I nonseminomatous germ cell tumors, excellent treatment results can be achieved that are comparable to primary retroperitoneal lymph node dissection. Tumor markers and computerized tomography are highly reliable for detecting relapse. Lymphangiography is still of staging value. Pathological factors may influence the choice of adjuvant treatment. However, relapse risks of 50% to 60% are maximally achieved with presently available prognostic factors, and so sparing morbidity of adjuvant treatment by a surveillance protocol remains a feasible option even in these patients. 相似文献
42.
Clinical Profile of Commotio Cordis: An Under Appreciated Cause of Sudden Death in the Young During Sports and Other Activities 总被引:3,自引:0,他引:3
BARRY J. MARON M.D. MARK S. LINK M.D. PAUL J. WANG M.D. N.A. MARK ESTES III M.D. 《Journal of cardiovascular electrophysiology》1999,10(1):114-120
Blunt Chest Impact Leading to Cardiac Arrest. Not particularly well recognized are athletic Held catastrophes in which virtually instantaneous cardiac arrest is produced by nonpenetrating chest blows in the absence of heart disease or identifiable morphologic injury to the chest wall or heart (commotio cordis). To better characterize the clinical profile of this syndrome, we have assembled 70 cases, including 34 occurring during organized competitive athletics and 36 others that occurred during informal recreational sports at home, school or the playground, or during nonsporting activities. Ages were 2 to 38 (mean age: 12) with 70% < 16 years old. Most common sports involved were youth baseball (n = 40), softball (n = 7), and ice hockey (n = 7). Seven (10%) of the 70 commotio cordis victims, including six with documented ventricular fibrillation, have survived the consequences of their chest blow. Eleven of the events (16%) occurred despite the presence of chest padding believed to be potentially protective. Four victims experienced modest chest blows while in circumstances completely unrelated to sports activities; three of the four individuals who delivered these blows were ultimately convicted of criminal acts within the justice system. An experimental model of low-energy chest wall impact demonstrates that commotio cordis events are due largely to the exquisite timing of blows during a narrow window within the repolarization phase of the cardiac cycle, 15 to 30 msec prior to the peak of the T wave. 相似文献
43.
自体骨髓干细胞移植治疗失代偿期肝硬化 总被引:12,自引:2,他引:12
选择36例失代偿期肝硬化患者,年龄37~59岁,患者在无菌条件下,从髂后上棘抽取骨髓100~200mL,在体外分离纯化骨髓干细胞后,局部麻醉下经股动脉插管经肝动脉将分离的骨髓干细胞移植于肝脏。自移植后12周,25例(69.4%)患者谷丙转氨酶逐渐降低,由平均(2788.56±357.90)nkat/L降至(1077.05±440.25)nkat/L;22例(61.1%)患者总胆红素逐渐下降,由平均(151.47±25.77)μmol/L降至(69.93±18.86)μmol/L;27例(75%)患者白蛋白逐渐升高,由平均(25.17±11.79)g/L升至(30.87±12.17)g/L。在干细胞移植后凝血酶原活动度逐渐上升,由术前平均(25.89±12.67)%上升至术后12周的(50.39±19.38)%,患者凝血机制明显改善。移植后大多数患者身体状况有明显的改善;移植后12周腹水减轻的19例(52.7%),食欲改善的28例(77.7%),体力好转20例(58.3%),腹胀减轻17例(47.2%),36例干细胞移植患者未出现严重并发症。 相似文献
44.
A humanised tissue‐engineered bone model allows species‐specific breast cancer‐related bone metastasis in vivo 下载免费PDF全文
VMC Quent AV Taubenberger JC Reichert LC Martine JA Clements DW Hutmacher D Loessner 《Journal of tissue engineering and regenerative medicine》2018,12(2):494-504
Bone metastases frequently occur in the advanced stages of breast cancer. At this stage, the disease is deemed incurable. To date, the mechanisms of breast cancer‐related metastasis to bone are poorly understood. This may be attributed to the lack of appropriate animal models to investigate the complex cancer cell–bone interactions. In this study, two established tissue‐engineered bone constructs (TEBCs) were applied to a breast cancer‐related metastasis model. A cylindrical medical‐grade polycaprolactone‐tricalcium phosphate scaffold produced by fused deposition modelling (scaffold 1) was compared with a tubular calcium phosphate‐coated polycaprolactone scaffold fabricated by solution electrospinning (scaffold 2) for their potential to generate ectopic humanised bone in NOD/SCID mice. While scaffold 1 was found not suitable to generate a sufficient amount of ectopic bone tissue due to poor ectopic integration, scaffold 2 showed excellent integration into the host tissue, leading to bone formation. To mimic breast cancer cell colonisation to the bone, MDA‐MB‐231, SUM1315, and MDA‐MB‐231BO breast cancer cells were cultured in polyethylene glycol‐based hydrogels and implanted adjacent to the TEBCs. Histological analysis indicated that the breast cancer cells induced an osteoclastic reaction in the TEBCs, demonstrating analogies to breast cancer‐related bone metastasis seen in patients. 相似文献
45.
NORMAN S. MILLER M.D. MARK S. GOLD M.D. BETH M. BELKIN M.D. Ph.D. ARYEH L. KLAHR M.D. 《Addiction (Abingdon, England)》1989,84(12):1491-1498
Genetic research in alcoholism has made major advances in recent decades. Twin, adoption, high-risk and familial studies have demonstrated an inheritance factor in alcoholism. Few studies have demonstrated a genetic predisposition to cocaine and cannabis dependence. Two hundred and sixty-three inpatients were given a structured psychiatric interview retrospectively (180) and prospectively (113) to obtain DSM-III-R diagnosis of cocaine, alcohol and cannabis dependence disorders in the inpatients and of alcohol dependence in family members. Our study reveals a large number of cocaine dependents with a positive family history for alcohol dependence. Approximately 50% of cocaine addicts had at least a first or second degree relative with a diagnosis of alcohol dependence when studied by the family history and study methods. As many as 89% of cocaine dependents diagnosed by DSM-III-R criteria for cocaine dependence qualified for other alcohol and drug dependence diagnoses. Our study finds a high prevalence of alcohol (67% and 89%) and cannabis dependence (51% and 46%) in patients with cocaine dependence. Previous reports regarding alcohol and other drug dependence among cocaine dependents and their families are few and inconclusive. The diagnosis of other drug and alcohol dependence in cocaine dependence and in family members of cocaine dependents has important impact on etiology, prognosis and treatment. 相似文献
46.
True Incidence of Pacemaker Syndrome 总被引:6,自引:0,他引:6
DEBRA HELDMAN DANIEL MULVIHILL HAROLD NGUYEN JOHN C. MESSENGER ARLENE RYLAARSDAM KARLA EVANS MARK J. CASTELLANET 《Pacing and clinical electrophysiology : PACE》1990,13(12):1742-1750
HELDMAN, D., ET AL.: True Incidence of Pacemaker Syndrome. Although the purported incidence of pacemaker syndrome according to the literature is only 5%–15%, this is based on a series of patients with VVI pacing. Increasing numbers of studies are being reported in which patients prefer the dual chamber mode despite little benefit being demonstrated on objective testing, suggesting that pacemaker syndrome may be more common than is generally reported. This study was designed to evaluate the reported symptoms in a series of patients programmed to both the VVI and one or more dual chamber modes. Forty unselected patients with dual chamber pacemakers were entered into a blind, randomized trial comparing the symptoms associated with VVI pacing to those associated with dual chamber pacing. Patients were randomized to either WI or dual chamber pacing. At the end of 1 week, questionnaires rating 16 different symptoms were completed. Blood pressure, LV function, presence of ventriculoatrial conduction, and ability to override the pacemaker were evaluated. The pacemaker was then programmed to the other mode. Overall, 12 of 16 symptoms were significantly worse in the VVI as compared to dual chamber mode. The most highly significant (p < 0.005) were shortness of breath, dizziness, fatigue, pulsations in the neck or abdomen, cough, and apprehension. Pacemaker syndrome was clinically recognized in 83% of patients paced in the WI mode with 65% of patients experiencing moderate to severe symptoms. There were no readily identified clinical, hemodynamic, or electrophysiological parameters that predicted which patients would develop pacemaker syndrome. Thus, when patients have an opportunity to experience both pacing modes in close proximity to one another, there is a high incidence of pacemaker syndrome in the VVI mode. 相似文献
47.
Titration of Power Output During Radiofrequency Catheter Ablation of Atrioventricular Nodal Reentrant Tachycardia 总被引:3,自引:0,他引:3
JONATHAN J. LANGBERG MARK HARVEY HUGH CALKINS RAFEL EL-ATASSI STEVEN J. KALBELEISGH FRED MORADY 《Pacing and clinical electrophysiology : PACE》1993,16(3):465-470
Radiofrequency lesions in the anterior, superior aspect of the tricuspid annulus result in selective elimination of fast pathway function in patients with typical atrioventricular (AV) nodal reentry tachycardia. This technique is simple and effective, but has been associated with a significant risk of inadvertent complete AV block. The purpose of this study was to compare the safety and effectiveness of two different techniques for radiofrequency catheter ablation of the fast AV nodal pathway. Initially, a fixed power output was used at each target site. This method was compared retrospectively to a newer technique where power output was gradually incremented at each site. Radiofrequency power was initially applied at 10 watts for 10–15 seconds. If no junctional ectopy or a change in PR intervoi was seen, power output was incremented by 2 to 4 watts every 10 to 15 seconds up to a maximum of 30 watts. Thirty seven of 38 (96%) patients treated using this incremental power output were cured of their AV nodal reentry tachycardia. None of these patients developed inadvertent complete AV block. In contrast, 92% of historic controls treated with a fixed power output between 20 and 30 watts achieved a primary success and nine of these 89 (10%) historic controls developed inadvertent complete AV block (P = 0.04). There was no difference in the amplitudes of atrial, His, or ventricular electrograms at the effective sites between the two groups. Conclusions: (1) the anterior approach to radiofrequency catheter ablation of typical AV nodal reentry is associated with a significant risk of inadvertent complete AV block if a fixed power output is used; (2) starting at low power and gradually incrementing the output during radiofrequency energy application reduces the risk of complete AV block; (3) this incremental technique does not compromise efficacy. 相似文献
48.
Analysis of the Effectiveness of In-Office and Transtelephonic Follow-Up in Terms of Pacemaker System Complications 总被引:1,自引:0,他引:1
MARK W. SWEESY STEVEN L. ERICKSON JUDY A. CRAGO KAREN N. CASTOR ROBERT L. BATEY RICHARD C. FORNEY 《Pacing and clinical electrophysiology : PACE》1994,17(11):2001-2003
A study was undertaken to determine the most effective method of pacemaker follow-up in terms of the total number of complications detected and yield per follow-up in single and dual chamber pacing systems. The analysis involved 9,786 patient records from 635 patients. The records were reviewed with respect to method of follow-up, number of chambers paced, and complications detected. Complications included: oversensing, undersensing, noncapture, pocket and diaphragmatic stimulation, pacemaker mediated tachycardia, crosstalk, pulse generator malfunction, lead malfunction, infection/erosion, premature end of service, exit block, and other miscellaneous problems. Eight thousand two hundred eighty-eight of the 9,786 follow-ups were performed in the office while 1,498 were transtelephonic. Single chamber pacing systems were implanted in 329 patients and 306 were dual chamber systems. A total of 599 complications were detected. Analysis yielded a per patient complication rate of 5.1 % (single chamber) and 8.4% (dual chamber) for in-office follow-up. This compared to a transtelephonic follow-up per patient complication rate of only 0.3% (single chamber) and 1.0% (dual chamber). In-office pacemaker follow-up is significantly more effective (P < 0.001) than transtelephonic follow-up in detecting both single and dual chamber pacemaker system complications. 相似文献
49.
Long-term Survival of VDD Pacing 总被引:1,自引:0,他引:1
RAFE CHAMBERLAIN-WEBBER EDWARD BARNES MARK PAPOUCHADO JONATHAN PITTS CRICK 《Pacing and clinical electrophysiology : PACE》1998,21(11):2246-2248
All patients with VDD systems implanted at a tertiary pacing center were identified from a computer database and data collected on pacing indications, follow-up duration, rate response, reasons for programming changes, and implant P wave amplitudes. Results: 366 implants were identified for which complete data were available for 335 leads implanted in 316 patients. The mean follow-up period was 24.1 months, and age at implant was 73.5 ± 11.8 years. During follow-up, 19 patients died (6%) and 62 (19.6%) were followed elsewhere. Indications for pacing were complete heart block, 56.6%; intermittent AV block, 21.8%; postablation complete heart block, 5.4%; 2:1 AV block, 13%; and others, 3.2%. Two groups: no mode change (NMC, n = 280) and mode change (MC, n = 36) were identified. Reasons for reprogramming in the MC group were as follows: atrial sensing, 11; AF/atrial flutter, 18; chronotropic incompetence, 3; and others 4. Significantly more MC patients had rate response programmed ON (44.4% vs 22.1%, P < 0.05). No significant differences between the two groups were found in other variables, including male gender (55.5% vs 54.6%), length of follow-up (27.1 ± 17.8 vs 23.8 ± 20.6 months), age at last follow-up (72 ± 12.3 vs 75.9 ± 11.9years), and P wave amplitude (1.7 ± 0.9 vs 1.8 ± 0.9mV). Conclusion: Reprogramming of VDD systems is infrequent. When necessary, it is usually prompted by atrial arrhythmias or failure of atrial sensing. When adequate atrial chronotropy has been verified, VDD is an acceptable alternative to DDD pacing and survives well over the long term. 相似文献
50.