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71.
Y Mahomed R D King D P Zipes W M Miles E N Prystowsky J J Heger J W Brown 《The Annals of thoracic surgery》1988,45(5):495-504
Kent bundle interruption for ventricular preexcitation has been successfully accomplished utilizing several different surgical techniques. The external closed-heart technique of Guiraudon combining surgical dissection and cryoablation has been used to interrupt 52 accessory pathways in 47 consecutive patients since May, 1985. The 35 male and 12 female patients ranged in age from 10 to 67 years (mean, 30 years). There were 25 left free wall, 13 right free wall, 13 posterior septal, and 1 anterior septal accessory pathways. Preoperative and intraoperative electrophysiological studies were performed in all patients to induce the arrhythmia and localize all accessory pathways. The operation consisted of dissection of the atrioventricular fat pad. Following this, the delta wave and retrograde accessory pathway conduction disappeared, thereby indicating successful pathway ablation. In 4 patients with right-sided accessory pathways, interruption of the pathway required cryoablation. Cryolesions (made with cryoprobe at -60 degrees C for two minutes) were created in the region of the accessory pathway insertion. All accessory pathways were successfully ablated without any deaths or heart block. Concomitant surgical procedures were performed in 4 patients. Two patients required a second operation the next day for an accessory pathway not found at the initial operation. Three patients had postpericardiotomy syndrome, and 4 had recurrent atrial fibrillation requiring therapy. The remaining patients have had no arrhythmia recurrence and have remained drug free after a follow-up of 1 month to 22 months (mean, 12.5 months). We conclude that the closed-heart technique of accessory pathway ablation is safe and reproducible, obviates the necessity for aortic cross-clamping and cardioplegic arrest, and allows instantaneous monitoring of conduction over the pathway. 相似文献
72.
Primary care referrals for lumbar spine radiography: diagnostic yield and clinical guidelines. 下载免费PDF全文
William Hollingworth Christopher J Todd Hugh King Tony Males Adrian K Dixon Kanti R Karia Ann Louise Kinmonth 《The British journal of general practice》2002,52(479):475-480
BACKGROUND: Primary care requests for radiographs of the lumbar spine have come under increasing scrutiny. Guidelines aiming to reduce unnecessary radiographs by limiting referrals to patients at high risk of serious disease have been widely distributed. Trial evidence suggests that guidelines can reduce radiography referrals. It is not clear whether this reduction has been achieved in routine practice. AIM: This study, using routine data, was conducted to measure trends in pnmary care referrals for lumbar spine radiography at two hospitals between 1994 and 1999. DESIGN OF STUDY: Analysis of primary care requests for lumbar spine radiography from computerised records. SETTING: Addenbrooke's Hospital, Cambridge (1 July 1994 to 30 June 1999), and Ipswich General Hospital (1 July 1995 to 30 June 1999), United Kingdom. METHOD: All primary care requests for lumbar radiography were identified electronically from computerised information systems. A random sample of 2100 radiography reports were classified according to clinical importance. These classifications were used to examine whether the proportion of radiographs demonstrating potentially more serious findings had increased between 1994 and 1999. RESULTS: There was no evidence that primary care referrals for radiography of the lumbar spine had decreased between 1994 and 1999 at either hospital. General practitioners did not progressively refer more high-risk patients for lumbar radiography. Only a small proportion of patients had important radiographic findings that might warrant specialist referral or specific therapy. CONCLUSION: The implementation of diagnostic guidelines offers much to the NHS. However in these two hospitals, the reduction in radiograph utilisation evident in trials was not achieved. Guideline development is a resource intensive process; distribution must be supported by more effective implementation strategies. 相似文献
73.
原钒酸钠对Ⅱ型糖尿病的降糖作用研究 总被引:13,自引:3,他引:10
目的 观察原钒酸钠对Ⅱ型糖尿病大鼠的降糖作用。方法 用高脂饲料灌胃正常大鼠 ,引起肥胖 ,测定血中游离脂肪酸浓度。同时应用正糖钳技术检测胰岛素抗性 ,对产生胰岛素抵抗的大鼠腹腔注射小剂量链脲菌素 (5 5mg·kg-1) ,然后筛选空腹血糖值大于 11 1mmol·L-1大鼠为糖尿病模型组。连续灌胃原钒酸钠 7d后 ,测定空腹血糖值。结果 ①大鼠喂食高脂饲料后 ,正糖钳实验中维持血糖稳态所需胰岛素量增多 ,为 (0 5 4± 0 0 2 )U·min-1,高于正常组 (P <0 0 1) ;同时血中游离脂肪酸浓度增加 ,从正常 (0 4 6 9±0 0 4 7)mmol·L-1至 (1 5 32± 0 2 91)mmol·L-1(P <0 0 1) ;②原钒酸钠对正常大鼠的血糖值无影响 ,而对Ⅱ型糖尿病大鼠的空腹血糖值及糖耐量曲线下面积有降低作用 (P <0 0 5 )。结论 实验结果证明了原钒酸钠可以明显降低Ⅱ型糖尿病大鼠的空腹血糖值 ,并且对糖耐量具有保护作用 相似文献
74.
N K Nakagawa F Donato-Júnior C S Kondo M King J O C Auler-Júnior P H N Saldiva G Lorenzi-Filho 《The European respiratory journal》2004,24(5):805-810
Furosemide is a potent diuretic that affects water transfer across the respiratory epithelium, which is closely related to the transepithelial potential difference (PD). Water is a critical factor that determines mucus transport; an important lung defence mechanism that removes particles and microorganisms from the respiratory system. The aim of the present study was to investigate the acute effects of furosemide and hypovolaemia on tracheal PD and mucus properties. A total of 36 male mixed-breed dogs were submitted to anaesthesia, mechanical ventilation and haemodynamic monitoring. They were randomly assigned to three groups consisting of: a control group, a furosemide (40 mg i.v.) + hypovolaemia group, and a furosemide (40 mg i.v.) + volume replacement group. Tracheal PD and mucus samples were collected at time 0, 1 and 2 h after intervention. Mucus properties were analysed by means of a magnetic microrheometer and in vitro mucociliary transportability on the frog palate. Compared to controls, furosemide decreased PD to intermediate values, and only significantly when associated with hypovolaemia (-13+/-5 and -8+/-2 mV, time 0 and 2 h, respectively). In addition to the direct effect of furosemide, these results indicate that hypovolaemia also affects ion transport in the tracheal membrane. Furosemide and hypovolemia have no acute effects on respiratory mucus properties. 相似文献
75.
Microvascular complications of diabetes. 总被引:3,自引:0,他引:3
Zhiheng He George L King 《Endocrinology & Metabolism Clinics of North America》2004,33(1):215-38, xi-xii
76.
77.
目的研究人参皂甙对β淀粉样蛋白(βamyloid,Aβ)1-40诱导THP-1细胞表达诱导型一氧化氮合酶(inducible nitric oxide synthase,iNOS)和一氧化氮(nitric oxide,NO)的影响。方法用Western blotting测定THP-1细胞iNOS表达,以Griess法测定细胞上清中NO的浓度。结果Aβ模型组iNOS的表达明显高于对照组(P<0.01)。与模型组比较,人参皂甙可明显减少THP-1细胞iNOS的表达和NO的产生(P<0.05)。随着人参皂甙剂量的增大,人参皂甙可引致THP-1细胞iNOS的表达和NO的产生明显减少(P<0.05),且有剂量依赖性。结论人参皂甙可抑制THP-1细胞iNOS的表达,进一步影响NO的产生。 相似文献
78.
Paige King Xiaowei Song Kenneth Rockwood 《The American journal of geriatric psychiatry》2006,14(10):893-896
OBJECTIVE: Having demonstrated that dementia of acute onset represents a distinct syndrome with distinct outcomes, the authors investigated whether similar attributes describe cognitive impairment of acute onset (CIAO). METHODS: The authors conducted a secondary analysis of the Consortium to Investigate Vascular Impairment of Cognition study. RESULTS: Ninety patients met our criteria for CIAO. Compared with cognitive impairment of gradual onset, CIAO was associated with vascular features (odds ratio [OR]: 12.3, 95% confidence interval [CI]: 3.2-47.9), dementias other than Alzheimer disease (OR: 6.5, 95% CI: 2.1-20.8), and decreased survival (hazard ratio: 2.8, 95% CI: 1.6-4.6). CONCLUSIONS: Patients with CIAO are clinically identifiable and have distinct outcomes. 相似文献
79.
A 74 year old man with light-chain myeloma developed amyloidosis with macroglossia after 10 years of therapy with alkylating agents. Over a 2-year period his tongue enlarged to persistently protrude from his mouth, inhibit his speech, interfere with normal swallowing and eventually threaten his airway. As a life-saving procedure the tumorous anterior two-thirds of the tongue was resected, with excellent primary healing. Within two weeks the patient's speech became comprehensible and his ability to eat returned to normal. Although rare in amyloidosis, massive macroglossia may occur and surgical correction is easily achieved. 相似文献
80.
A case of surrogate pregnancy is described in the sister of a 40-year-old hysterectomized woman where two oocytes of the latter were fertilized in vitro with known donor sperm and transferred into the surrogate. A normal singleton pregnancy developed which was complicated after 24 weeks of gestation with recurrent antepartum hemorrhages due to grade 3 placenta praevia. A healthy female baby was delivered by elective cesarean section at 36 weeks of gestation. The legal, social, psychological, and ethical issues of surrogacy remain unsettled and are discussed in this case report. 相似文献