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61.
Summary. The ideal operation for a young woman born without a vagina would be a one stage procedure, creating a functionally normal vagina without cosmetically unattractive scars, without the need for subsequent dilatation, stents or obturators. This goal was achieved with a free flap vaginoplasty using a full thickness skin graft taken from the scapula region. The blood supply of the graft was maintained by microvascular anastomosis of the graft pedicles to vessels in the groin. The operation has been performed in three young women who were born with uterine hypoplasia and vaginal agenesis. We experienced no unexpected complications, the procedure was well tolerated and left our patients with a good length, fully functional vagina. However, the operation is a major undertaking and needs to be performed by those with expertise in plastic surgery as well as in gynaecology.  相似文献   
62.
The streptozotocin (STZ)-diabetic rat, the most commonly employed model of experimental diabetic neuropathy, is characterised by a reduction in nerve conduction velocity, pain threshold and blood flow. Whether or not structural abnormalities underlie these functional abnormalities is unclear. 10 adult male Sprague–Dawley STZ-diabetic rats (diabetes duration 27 d) and 10 age-matched (23 wk) control animals were studied. Motor nerve conduction velocity (m s−1) was significantly reduced in diabetic (41.31±0.8) compared with control (46.15±1.5) animals ( P <0.001). The concentration of sciatic nerve glucose ( P <0.001), fructose ( P <0.001) and sorbitol ( P <0.001) was elevated, and myoinositol ( P <0.001) was reduced in diabetic compared with control animals. Detailed morphometric studies demonstrated no significant difference in fascicular area, myelinated fibre density, fibre and axon areas as well as unmyelinated fibre density and diameter. Endoneurial capillary density, basement membrane area and endothelial cell profile number did not differ between diabetic and control animals. However, luminal area ( P <0.03) was increased and endothelial cell area ( P <0.08) was decreased in the diabetic rats. We conclude there is no detectable structural basis for the reduction in nerve conduction velocity, pain threshold or blood flow, observed in the streptozotocin diabetic rat.  相似文献   
63.
WISH, M., ET AL.: Steroid-Tipped Leads Versus Porous Platinum Permanent Pacemaker Leads: A Controlled Study. There is little data directly comparing steroid-tipped permanent pacemaker leads to otherwise state-of-the-art porous platinum leads. Eighteen patients receiving unipolar generators capable of low voltage outputs were randomized at the time of implant to receive either steroid-tipped leads or porous platinum leads. All leads were unipolar, tined, passive fixation, and placed in the right ventricular apex or atrial appendage. This study is single center. At implant, threshold pulse width was determined at 3 voltages (2.5, 1.5, and 0.8 V). Follow-up thresholds were determined at weeks 1, 2, 3, and 4, and at 3 and 6 months. There was no difference in implant thresholds or amplitudes for sensing. By 2 weeks postimplant, lower thresholds were noted for the steroid leads, and this discrepancy grew more significant with time. There was no significant postimplant rise in threshold for steroid-tipped leads. At 6 months, the average threshold pulse width for ventricular steroid leads at 0.8 V was 0.3 ± 0.1 msec. In contrast, five patients with standard leads did not capture at maximum pulse width at 0.8 V (p < 0.0001). There was no significant difference in the amplitude of the chronic atrial electrogram. This study shows steroid-tipped leads to offer a significant advantage in reducing thresholds early postimplant and chronically.  相似文献   
64.
Genetic and environmental contributions to smoking   总被引:3,自引:0,他引:3  
We estimate the magnitude of genetic and shared environmental contributions to risk of initiation and maintenance of smoking. Genetic models were fitted to data from 2 204 male-male monozygotic and 1 793 male-male dizygotic twin pairs from the Vietnam Era Twin Registry who responded to smoking questions on a 1987 mail and telephone survey. The best fitting model allowed for both genetic and shared environmental effects on smoking initiation, accounting for 50% and 30% of the variance in risk, but allowed for only genetic effects, (accounting for 70% of the variance in risk), on persistence in smoking among those who had become regular smokers. This finding of a major genetic influence on smoking persistence confirms similar results from studies in Scandinavia and Australia. The role of heritable traits such as nicotine sensitivity should be addressed in smoking prevention and cessation efforts.  相似文献   
65.
PR/RR Interval Ratio During Rapid Atrial Pacing:   总被引:3,自引:0,他引:3  
Method for Confirming Slow Pathway Conduction. Introduction: Although the AV conduction curve in patients with AV nodal reentrant tachycardia (AVNRT) is usually discontinuous, many patients with this arrhythmia do not demonstrate criteria for dual AV nodal pathways. During rapid atrial pacing, the PR interval often exceeds the pacing cycle length when there is anterograde conduction over the slow pathway and AVNRT is induced. The purpose of this prospective study was to determine the diagnostic value of the ratio of the PR interval to the RR interval during rapid atrial pacing as an indicator of anterograde slow pathway conduction in patients undergoing electrophysioiogic testing. Methods and Results: The PR and RR intervals were measured during rapid atrial pacing at the maximum rate with consistent 1:1 AV conduction in four study groups: (1) patients with inducible AV nodal reentry and the classical criterion for dual AV nodal pathways during atrial extrastimulus testing (AVNRT Group 1); (2) patients with inducible AV nodal reentry without dual AV nodal pathways (AVNRT Group 2); (3) control subjects ≤ 60 years of age without inducible AV nodal reentry; and (4) control subjects > 60 years of age without inducible AV nodal reentry. For both groups of patients with inducible AV nodal reentry, AV conduction was assessed before and after radiofrequency ablation of the slow AV nodal pathway. Before slow pathway ablation, the PR/RR ratio exceeded 1.0 in 12 of 13 AVNRT Group 1 patients (mean 1.27 ± 0.21) and 16 of 17 AVNRT Group 2 patients (mean 1.18 ± 0.15, P = NS Group 1 vs Group 2). After slow pathway ablation, the maximum PR/RR ratio was < 1.0 in all AVNRT patients (Group 1 = 0.59 ± 0.08, P < 0. 00001 vs before ablation: Group 2 = 0.67 ± 0.11; P < 0.00001 vs before ablation). Among both groups of control subjects, the PR/RR ratio was > 1.0 in only 3 of 27 patients with no relation to patient age. Conclusion: The ratio of the PR interval to the RR interval during rapid atrial pacing at the maximum rate with consistent 1:1 AV conduction provides a simple and clinically useful method for determining the presence of slow AV nodal pathway conduction. This finding may be particularly useful in patients with inducible AV nodal reentry without dual AV nodal physiology on atrial extrastimulus testing.  相似文献   
66.
The air-Q intubating laryngeal airway (ILA) is a new supraglottic airway device which may overcome some limitations inherent to the classic laryngeal mask airway for tracheal intubation. We present a case series of patients with anticipated difficult airway in whom the air-Q ILA was successfully used as a conduit for fiberoptic intubation.  相似文献   
67.
Background: Pharmacologic therapies to prevent stroke in atrial fibrillation (AF) have numerous limitations, prompting the development of device-based therapies. We investigated whether an electrogram-based approach using a novel hollow suture can safely capture and ligate the left atrial appendage (LAA).
Methods and Results: A novel system for closure of the LAA within the confines of the closed pericardium with a single sheath puncture was tested in 4 dogs. The tool used to grasp the appendage was fitted with electrodes and utilized electrical navigation to identify and confirm LAA capture. A hollow suture preloaded with a mechanical support wire to permit its manipulation and fluoroscopic visualization was advanced over the grasper, and the wire removed after the suture was positioned. The LAA was successfully closed in all dogs. In 2 dogs, after closure, a thoracotomy was performed and the LAA amputated without bleeding, confirming closure integrity. Necropsy confirmed closure in all animals.
Conclusions: Using electrical navigation, percutaneous epicardial LAA ligation with a remotely tightened suture was performed successfully within the confines of the intact pericardial space. This technique may allow decreasing the risk of stroke in AF patients without the need for thoracotomy or an endocardially placed prosthetic device.  相似文献   
68.
Aliment Pharmacol Ther 31 , 640–647

Summary

Background The thiopurine drugs, azathioprine and mercaptopurine (MP), are established treatments for IBD. However, therapeutic failure caused by adverse drug reactions occurs frequently. Aim To study combination of allopurinol with reduced‐dose thiopurine in an attempt to avoid adverse drug reactions in the treatment of IBD. Methods Patients with drug reactions to full‐dose thiopurines were recruited for combination therapy in two IBD centres in this retrospective study. Dosing was guided by measuring thiopurine methyltransferase (for UK patients) or thioguanine nucleotides and methyl‐6MP (Australian patients). Response was monitored by clinical activity indices. Results Of 41 patients, 25 had non‐hepatic and 16 had hepatitic reactions. Clinical remission was achieved in 32 patients (78%) with a median follow‐up of 41 weeks (range 0.5–400). Patients who did not respond to combination therapy tended to fail early with the same adverse reaction. The relative risk of having an adverse reaction with methyl‐6MP in the top interquartile range was 2.7 (1.3–28) times that with methyl‐6MP in the lower three quartiles (95% confidence interval). Conclusion The combined experience from our centres is the largest reported experience of this combination therapy strategy in IBD, and the first to provide evidence for benefit in thiopurine and allopurinol co‐therapy to avoid non‐hepatitic adverse drug reactions.  相似文献   
69.
ABSTRACT. A report of the findings of a sample survey of alcohol consumption by Tasmanian High School pupils (age 12–16) in 1979.
The sample of 646 boys and 565 girls was drawn from 14 Tasmanian High Schools and is considered to be representative of High School pupils in that State. The main findings are that
  • (a) 

    a marked increase in drinking particularly by boys occurs between age 14 and 15.

  • (b) 

    by age 11 the majority of boys and girls have had their first drink, and there is a tendency to more widespread early experimentation with alcoholic drinks over the period 1975–1979.

  • (c) 

    An association is observed between drinking behaviour and health outcomes of drinking as perceived by the students.

  相似文献   
70.
Amplified rhinovirus colds in atopic subjects   总被引:1,自引:0,他引:1  
Abstract. Evidence suggests that atopic individuals may be predisposed to more severe rhinoviral colds coupled to a worsening of existing airway disease than those with asthma. The role of atopy and IgE levels, as well as their relationship to clinical disease expression have not been defined. We hypothesized that an allergic diathesis modulates rhinoviral colds and have initiated studies of normal, atopic and asthmatic subjects employing experimental rhinoviral infection, with measurements of symptom scores, viral shedding and cultures, albumin in nasal washes and serological responses. Twenty-two subjects (11 normal, 5 atopic, 6 atopic and asthmatic) participated and were inoculated with human rhinovirus serotype 16 (HRV 16). Measurements of neutralizing antibody and viral culture were performed at screening, pre-inoculation, during the cold and at 8–10 weeks convalescence. Daily symptoms were noted, nasal washes done, IgE measured and atopy was diagnosed by skin tests. Seventeen volunteers developed clinical colds as assessed by symptom scores, virus shedding was demonstrated (with positive culture) in all subjects and a fourfold or higher seroconversion occurred in 11/22. Neutralizing HRV antibody developed unexpectedly in 10 subjects between screening and inoculation and the presence or absence of this pre-inoculation antibody determined subsequent severity of colds in normal but not in atopic subjects. Atopic antibody positive individuals developed severe clinical colds that were independent of preinoculation antibody in contrast to normal subjects who developed mild colds in the presence of a neutralizing antibody (.P= 0.01). Both atopic and normal antibody negative subjects developed severe colds. This differential response was matched by nasal wash albumin levels which were significantly increased (P= 0–01) during the cold in atopic (but not in normal) volunteers with pre-inoculation antibody. Levels of IgE were not correlated with severity of clinical disease or viral shedding. Our studies of HRV disease in atopic subjects suggest heightened susceptibility to the detrimental effects of colds; additional studies are needed to clarify the relevant mechanisms.  相似文献   
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