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91.
BACKGROUND: It is still unclear whether age per se is associated with preservation of renal functional reserve, that is, of the increase in glomerular filtration rate (GFR) induced by appropriate vasodilating stimulus. METHODS: To gain insights into this issue, we evaluated the renal response to a maximal vasodilating stimulus, represented by the combined infusion of mixed amino acid solution (AA) and dopamine at renal dose (D), in 10 young subjects (median age of 30 years, range of 19 to 32) and in 11 subjects of older age (median age of 67 years, range of 65 to 76). Two further age-matched groups of young (N = 15) and older (N = 11) living kidney donors underwent renal needle biopsy immediately before nephrectomy to perform semiquantitative scoring (0 to 3) of arteriosclerosis in intrarenal arteries. All of the study subjects were nonsmokers with healthy status proven by extensive diagnostic evaluation excluding any risk factor of renal dysfunction. RESULTS: Basal renal plasma flow (RPF) and GFR were proportionally lower in older subjects (RPF, 361 +/- 29 vs. 618 +/- 34 mL/min/1.73 m(2), P < 0.001; GFR, 79 +/- 4 vs. 127 +/- 5.8 mL/min/1.73 m(2), P < 0.001). After AA + D, a significant increase of RPF and GFR was observed in both groups, but the older subjects exhibited a smaller percentage increment (RPF, 25.5 +/- 4.8 vs. 42.4 +/- 5.8, P < 0.05; GFR, 19.6 +/- 5.7 vs. + 33.8 +/- 6.4, P < 0.05). Furthermore, the maximal vasodilating stimulus was not able to restore renal hemodynamics in older subjects to the level measured in young controls at baseline. Renal vascular resistances were higher (P < 0.05) in the older subjects both at baseline (0.19 +/- 0.02 vs. 0.09 +/- 0.004 mm Hg/mL/min) and after AA + D (0.14 +/- 0.01 vs. 0.06 +/- 0.004). Light microscopy examination detected the presence of a greater degree of arteriosclerosis at the level of interlobular and arcuate arteries (0.89 +/- 0.15 vs. 0.45 +/- 0.08) and interstitial fibrosis/tubular atrophy (1.18 +/- 0.13 vs. 0.53 +/- 0.13) in older than in young subjects. CONCLUSIONS: Therefore, aging has adverse effects on renal function despite the absence of any risk factor for renal disease, including chronic smoking: (1) GFR and RPF are lower, and (2) the renal response to maximal vasodilating stimulus is impaired. These aging-related alterations of renal hemodynamics are possibly due to organic lesions in renal vasculature.  相似文献   
92.
OBJECTIVE: To compare transdermal oestrogen with oral diethylstilbestrol (DES) as a second- or third-line hormonal therapy in the treatment of prostate cancer. PATIENTS AND METHODS: In all, 32 assessable patients who, having already had a relapse on at least one line of hormonal therapy, received transdermal oestrogen therapy as an alternative to oral DES, when DES became unavailable. RESULTS: Whereas DES had controlled the prostate-specific antigen (PSA) level for a median of 29 weeks in a group of 15 patients in remission, all but one had an increase in PSA level (median 86% increase above the starting PSA level) within a median of 8 weeks after introducing transdermal therapy. This increase was reversed in seven of the 12 patients who recommenced DES therapy. CONCLUSION: Although the use of transdermal oestrogen is currently attracting enthusiasm as a first-line treatment for prostate cancer, these results show that for second- or third-line therapy further cautious research with careful monitoring is necessary.  相似文献   
93.

Background  

The optimal management of chronic ruptures of the Achilles tendon is surgical reconstruction. Reconstruction of the Achilles tendon using peroneus brevis has been widely reported. Classically, these procedures involve relatively long surgical wounds in a relatively hypovascular area which is susceptible to wound breakdown.  相似文献   
94.
Multi-detector computed tomography (MDCT) has become an alternative to coronary angiography in diagnosis of graft occlusion and stenosis after coronary artery bypass. A literature search was performed for studies comparing angiography to 8-slice, 16-slice, and 64-slice MDCT in the assessment of coronary grafts. In assessing occlusion, 14 studies produced pooled sensitivity of 97.6%, specificity of 98.5%, diagnostic odds ratio of 934.2, area under the curve of 0.996, and Q* of 0.977. Ninety-six percent of all grafts were visualized for occlusion assessment. Beta blockers, symptomatic status, and postoperative period did not significantly affect diagnostic performance. Stenosis assessment produced sensitivity of 88.7% and specificity of 97.4%. Eighty-eight percent of patent grafts could be assessed for stenosis. The diagnostic accuracy of MDCT approaches angiography for diagnosing graft occlusion and stenosis in patients with venous and arterial coronary bypass grafts. Our findings show that cardiac surgeons will need to interpret MDCT images of both native and grafted vessels soon in preparation for primary or re-do coronary bypass grafting procedures.  相似文献   
95.
The Authors report on a rare case of blunt traumatic injury of the gallbladder. A careful clinical examination, an abdominal ultrasonography and a contrast material-enhanced computed tomography have a primary importance for a correct diagnosis. Laparoscopic surgery has an important diagnostic and, in selected cases, therapeutic role. In all traumatic gallbladder ruptures, after an accurate search of eventual associated injuries of other abdominal organs, cholecystectomy is considered the treatment of choice.  相似文献   
96.
OBJECTIVES: To present the surgical, functional, and cosmetic results of anterior pelvic floor reconstruction in female exstrophic patients who underwent single-stage surgical repair. To verify differences in outcome from male exstrophic patients. METHODS: Among the 31 exstrophy-epispadias complex (EEC) patients treated in 10 yr, 13 (42%) were females. We studied 10 of them (9 classic exstrophies and 1 prolapsing epispadia), aged 2 d to 6 yr, who received one-stage repair with pelvic floor reconstruction. The reconstructive steps were posterior pelvic osteotomy, en bloc mobilisation of bladder neck-urethra/vagina within the midline pelvic floor, symmetrical reassembly of the muscular complex that constitutes the pelvic diaphragm (using a bipolar stimulator), tubularisation and elongation of the bladder neck and urethra, and genitoplasty. At 2- to 3-yr follow-up, bladder capacity and dry intervals were evaluated by cystogram and urodynamic study, respectively. Surgical complications and cosmetic appearance were also assessed. Results were compared with a group of 18 male EEC patients treated in the same period with similar technique. Fisher exact test and chi-square test were used for statistical analysis. RESULTS: No bladder/urethra dehiscence, exstrophy relapse, or uterine procidentia were observed. Cosmesis was fully satisfying in all. Bladder capacity ranged from 35 to 137 ml (mean: 87). Cyclic voiding with 45- to 90-min dry intervals was achieved in 7 patients (70%), but stress incontinence was present in 5 patients. Volitional micturition control was achieved in 5 of 6 (83.3%) girls aged 4-8 yr. In the male group, we observed two surgical complications (glans disruption and urethrocutaneous fistula) and one poor cosmetic outcome. Mean bladder capacity was 70 ml (range: 25-140). Dry intervals were present in 6 patients (33%). Volitional voiding was achieved in 5 of 12 (40%) male exstrophic patients older than 4 yr, with little stress incontinence. Female and male EEC patients presented significantly different outcomes (p<0.05) regarding both surgical complications and functional bladder behaviour. CONCLUSIONS: Pelvic floor reconstruction and its correct relationship with the lower genitourinary tract may facilitate the development of volitional micturition control. Female patients behaved slightly better than males concerning dry intervals and coordinated bladder activity achievement.  相似文献   
97.
BACKGROUND: This study assessed the endovascular embolization of splenic artery aneurysms and false aneurysms with special consideration given to postoperative complications. METHODS: Fifteen patients (11 women; mean age, 56 y; range, 39-80 y) with splenic artery aneurysm (n = 13) or false aneurysm (n = 2) were treated with coil embolization. The lesion was asymptomatic in 9 patients, symptomatic in 5 patients, and ruptured in 1 patient. The mean aneurysm diameter was 33 +/- 23 mm (range, 15-80 mm). Postoperative follow-up evaluation included a clinical visit and spiral computed tomography at 1, 4, and 12 months, and yearly thereafter. RESULTS: Endovascular treatment was possible in 14 patients (93%) (1 failure: neck cannulation). Perioperative mortality was not observed. Morbidity included postembolization syndrome in 5 patients (30%). Neither pancreatitis nor spleen abscess occurred. The mean follow-up period was 36 months (range, 3-60 mo). During follow-up evaluation we detected 1 sac reperfusion that was sealed successfully with additional coils. Surgical conversion or open repair were never required. CONCLUSIONS: At our institute, endovascular treatment represents the first-line treatment for splenic artery aneurysms. Postembolization syndrome and infarcts are common events but generally resolve without sequelae.  相似文献   
98.

Purpose

Despite the overall success of the surgical anterior cruciate ligament (ACL) reconstruction, some patients still present with instability symptoms even after the surgery, mainly due to the presence of associated lesions. At present, the pivot shift test has been reported to be the benchmark to assess rotatory knee laxity. The purpose of this study was to quantitatively evaluate rotatory knee laxity at time-zero in order to determine whether detected post-reconstruction laxity was predictable by its value measured before the reconstruction, which was hypothized to be influenced by the presence of associated lesions.

Methods

Rotatory knee laxity was retrospectively analysed in 42 patients, including two different ACL reconstructions. The maximal anterior displacement and the absolute value of the posterior acceleration reached during the reduction of the tibial lateral compartment were intra-operatively acquired by using a navigation system and identified as discriminating parameters. For each parameter, statistical linear regression analysis (line slope and intercept) was performed between pre- and post-reconstruction values.

Results

No statistically significant influence of the initial posterior acceleration on the post-reconstruction outcome was found (line slope, p > 0.05), although a statistically significant line intercept was indeed identified (p < 0.001). A statistically significant influence on the surgery outcome was instead found for the initial value of the anterior tibial displacement (line slope = 0.39, p = 0.004), meaning that, on average, about 40 % of the post-reconstruction lateral compartment displacement could be explained by the corresponding pre-reconstruction value. Both of these findings highlighted the importance of intra-operative quantification of rotatory knee laxity to identify correct indications for the surgery.

Conclusions

This study provided important implications for the future possibility of defining a quantifying tool able to assess rotatory knee laxity during ACL reconstruction. This could allow detection of additional injuries to secondary restraints by easily performing rotatory knee laxity tests, which in turn could reduce post-surgical recurrence of knee instability.  相似文献   
99.
100.
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