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101.
The value of different resistance parameters in distinguishing biopsy-proved dysfunction of renal allografts 总被引:3,自引:2,他引:1
Frauchiger B.; Bock A.; Eichlisberger R.; Landmann J.; Thiel G.; Mihatsch M. J.; Jager K. 《Nephrology, dialysis, transplantation》1995,10(4):527-532
The data concerning the value of duplex sonography in diagnosingparenchymatous renal allograft dysfunction are controversial.Most early studies did not take into consideration the manyfactors influencing resistance parameters. We therefore performeda prospective, biopsy-controlled study with exclusion of allknown sources of error regarding resistance parameters. Furthermorewe investigated the value of a new resistance parameter, thesystolic deceleration percentage. Forty-seven duplex sonographicstudies were performed on 43 patients (30 male, 13 female, medianage 47 years, range 770). Fourteen studies were doneon normally functioning grafts (control group) an average of33 days after transplantation. Thirty-three studies were performedon dysfunctional grafts immediately prior to biopsy. Graftswhich had been transplanted more than a year previously or withvascular findings or any other clinical or sonographic pathologyprobably explaining function deterioration were excluded. Inall patients, the resistive index (RI), pulsatility index (PI)and systolic deceleration percentage (DP) were calculated inthe main renal artery and in the interlobar artery. Of the 33grafts with dysfunction, nine had vascular rejection (VR), 11interstitial rejection (IR), 11 cyclosporin A toxicity (CAT)and two other histologies (OR). The mean RI in normal grafts(NO) was 0.71±0.06 in the main artery and 0.68±0.06in the interlobar artery, in VR 0.86±0.12 and 0.80±0.18,in IR 0.72±0.05 and 0.70±0.07, in CAT 0.67±0.06and 0.65±0.07 and in OR 0.64±0.07 and 0.60±0.01.For PI, the values were 1.45±0.23 and 1.41±0.28(NO), 3.5±2.13 and 2.92±2.16 (VR), 1.55±0.26and 1.46±0.33 (IR), 1.32±0.25 and 1.27±0.26(CAT) and 1.30±0.34 and 1.13±0.04 (OR). For DPwe calculated 28±5% and 29±6% (NO), 43±14%and 36±6% (VR), 29±9% and 27±9% (IR), 31±8%and 32±7% (CAT ) and 32±4% and 28±3% (OR).The sensitivity/specificity for VR with a cutoff mean+2 SD was0.44/1 for RI, 0.55/0.97 for PI and 0.33/0.89 for DP. It wasconcluded that:(1) despite the high selection of our patientgroup, diagnostic accuracy of duplex sonography for diagnosingparenchymatous function disorder in renal allograft remainsinsufficient; (2) in vascular rejection only, the resistanceparameters differ significantly from the values of normal allografts;(3) the higher the cutoff of resistance parameters, the betterthe specificity and the worse the sensitivity for diagnosingvascular rejection; (4) of all investigated resistance parameters,the RI is the most practical due to a simple measurement technique. 相似文献
102.
The objective was to determine whether vaginal topography accurately predicts the location of the pelvic viscera on fluoroscopy
in women with pelvic organ prolapse. Eighty-nine women undergoing preoperative evaluation for reconstructive pelvic surgery
at a tertiary care referral practice formed the study population. Each woman completed a comprehensive urogynecologic history
and physical examination, which included a quantified (POP-Q) assessment of her vaginal topography, as described by Bump et
al. In addition each woman underwent pelvic floor fluoroscopy (PFF). Visceral sites were selected which corresponded clinically
to the vaginal sites measured by the POP-Q. The most dependent portion of the bladder, small intestine, rectum and urethrovesical
junction was measured. Twenty-five (28%) women had stage II prolapse, 34 (38%) had stage III prolapse, and 28 (32%) had stage
IV prolapse. The remaining 2 women were symptomatic, with stage I prolapse. For the entire study population there was no correlation
between the fluoroscopic position of the small bowel and/or rectum and any apical or posterior wall POP-Q site (C, Ap or Bp).
There was no correlation with the fluoroscopic position of the UVJ at rest or with straining and the corresponding POP-Q site
(Aa). The fluoroscopic position of the most dependent portion of the bladder correlated only modestly with the upper (Ba,ρ=0.51) and lower Aa,ρ=0.68) anterior vaginal wall POP-Q sites. In women without prior surgery (n=33) there was only modest correlation between the fluoroscopic position of the bladder and the corresponding POP-Q site (Aa,ρ=0.71). In this unoperated subpopulation there was no correlation with PFF and any other POP-Q site. In women who had undergone
prior hysterectomy (n=25) or hysterectomy with anterior and/or posterior colporrhaphy (n=17), there was only a modest correlation of the most dependent portion of the bladder and the upper anterior vaginal wall
site (Bb,ρ=0.67 andρ=0.55, respectively). It was concluded that vaginal topography does not reliably predict the position of the associated viscera
on PFF in women with primary or recurrent pelvic organ prolapse.
EDITORIAL COMMENT: The authors seek to evaluate whether physical examination of vaginal prolapse using the POP-Q test correlates
with fluoroscopic findings of visceral position. Surprisingly, little correlation is found, even in previously unoperated
patients. One reason for this lack of correlation between the two modalities of evaluation may lie in the use of two different
fixed points of reference: the POP-Q examination uses the hymen as the fixed point of reference, whereas the investigators
chose to use the posterior edge of the femur as a fixed bony point of reference when evaluating pelvic floor fluoroscopy in
the same patient. The lack of correlation between visual inspection of vaginal wall prolapse and what lies deep to that prolapse
should not be used to invalidate the use of the POP-Q as a means to evaluate pelvic prolapse. Rather, the findings support
the premise behind the ICS/AUGS/SGS committee on pelvic organ prolapse, specifically that clinical pelvic examination of the
vaginal walls looks at surfaces only, and as such cannot determine what, if any, organ lies deep to that surface. 相似文献
103.
Sinus augmentation has been advocated to be a surgical technique with predictable results in peri‐implant surgery. Endoscopic surgery of the maxillary sinus so far has been used as diagnostic procedure. In this paper, the use of endoscopy is described as a low invasive adjunctive technique in sinus floor augmentation. After preparation of the mucoperiosteum, bone grafts can be placed under endoscopic control between sinus floor and mucoperiosteum. A laterobasal approach via a small osteotomy and a transalveolar approach are possible for mucosal elevation and graft placement. First clinical results are reported. Endoscopic sinus lift may contribute to a reduction of perioperative morbidity, reduction of oroantal fistulae and control of graft position. The less invasive technique may allow to extend the indication for sinus augmentation. 相似文献
104.
Incidence and prevalence of the sexual dysfunctions: A critical review of the empirical literature 总被引:11,自引:0,他引:11
The research which has assessed the incidence and prevalence of sexual dysfunctions is reviewed. Twenty-three studies are evaluated. Studies completed with community samples indicate a current prevalence of 5–10% for inhibited female orgasm, 4–9% for male erectile disorder, 4–10% for inhibited male orgasm, and 36–38% for premature ejaculation. Stable community estimates with regard to the current prevalence of female sexual arousal disorder, vaginismus, and dyspareunia are not available. Recent studies completed with clinical samples suggest an increase in the frequency of orgasmic and erectile dysfunction and a decrease in premature ejaculation as presenting problems. Desire disorders have increased as presenting problems in sex clinics, with recent data indicating that males outnumber females. Methodological limitations of these studies are identified and suggestions for future research are offered. 相似文献
105.
The aim of the study was to identify the striated muscle forces hypothesized to assist bladder neck opening and closure in
females. Cadaveric dissection was used to identify the levator plate (LP), the anterior portion of pubococcygeus muscle (PCM),
the longitudinal muscle of the anus (LMA), and their relation to the bladder, vagina and rectum. X-ray video recordings were
made during coughing, straining, squeezing and micturition in a group of 20 incontinent patients and 4 controls, along with
surface EMG, urethral pressure and digital palpation studies. During effort, urethral closure appeared to be activated by
a forward muscle force corresponding to PCM, and bladder neck closure by backward muscle forces corresponding to LP and LMA.
During micturition the PCM force appeared to relax, allowing LP and LMA to pull open the outflow tract. The data appear to
support the hypothesis of specific directional muscle forces stretching the vagina to assist bladder neck opening and closure. 相似文献
106.
107.
108.
The purpose of the study was to compare the effect of voluntary pelvic floor muscle (PFM) contraction and vaginal electrical stimulation on urethral pressure. Twelve women with genuine stress incontinence, mean age 49.4 years (range 33–66) participated in the study. The urethral and bladder pressures were recorded simultaneously through a double-lumen 8 Ch catheter. The patients first performed three voluntary PFM contractions. Then two electrical stimulators, Conmax and Medicon MS 105, 50 Hz, were used in random order. A visual analog scale was used to measure pain and discomfort. Pain was reported to mean 6.8, SEM 0.64 (range 0.7–9.9) and mean 6.1, SEM 0.81 (range 0–9.1) with Conmax and Medicon MS 105, respectively. The mean paired difference in favor of voluntary contraction with Conmax was ?8.0, SD 6.7,P=0.0067, and with Medicon MS 105 it was ?12.2, SD 5.9,P=0.0022. The results demonstrated that voluntary PFM contraction increased urethral pressure significantly more than did vaginal electrical stimulation. 相似文献
109.
110.
小檗碱对大鼠阴茎海绵体磷酸二酯酶5mRNA水平的影响 总被引:3,自引:0,他引:3
目的 :检测大鼠阴茎海绵体中磷酸二酯酶 5 (PDE5 )mRNA的表达 ,进而探讨小檗碱 (berberine ,Ber)的分子作用机制。 方法 :通过逆转录酶链反应 (RT PCR)技术检测大鼠阴茎海绵体中PDE5mRNA的表达。 结果 :大鼠阴茎海绵体中有PDE5A1和PDE5A2mRNA的表达 ,以PDE5A2为主要的异构酶。与内参照 β 肌动蛋白相比 ,对照组、Ber孵育 1和 3h组的PDE5A1及PDE5A2基因mRNA的相对表达量分别为 :0 .2 2± 0 .0 2 ,0 .4 1± 0 .0 1 ;0 .1 5± 0 .0 1 ,0 .34± 0 .0 2 ;0 .1 0± 0 .0 1 ,0 .1 2± 0 .0 1。与对照组相比 ,PDE5A1、PDE5A2的mRNA表达 ,在Ber孵育 1h组降低了 32 %和 1 7%,3h组降低了 5 5 %和 71 %,其中尤以应用Ber 3h后PDE5A2的mRNA减少最为明显 (n =5 ,P <0 .0 1 )。 结论 :Ber对NO cGMP信号通路的下游关键酶 (PDE5 )具有一定的调控作用 ,尤其是抑制PDE5A2的mRNA表达 ,为Ber治疗勃起功能障碍的分子机制之一。 相似文献