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111.
Erectile dysfunction is a recognized complication of prostate and bladder radical surgery, although there is significant variation in the reported risk, much of this variability is related to the retrospective nature of most previous studies. Undoubtedly, the quality of life of bladder and prostate cancer patients would be much improved if both normal micturition and potency are preserved, which is the subject of this article. Quality of life studies can delineate sexual function after radical prostatectomy, including the use of sexual aids. Penile erection is a neurovascular event modulated by neurotransmitters and hormonal status. The penis is innervated by autonomic and somatic nerves. Both surgery and radiation therapy appear to affect such a mechanism. Radiation is thought to produce Erectile Dysfunction (ED) by accelerating microvascular angiopathy causing cavernosal fibrosis or stenosis of the pelvic arteries and by accelerating existing arteriosclerosis, leading to vascular impotence. Years may elapse before clinically significant ED occurs. Criteria that influence recovery of erections after surgery include younger patient age, stronger erections before operation, preservation of the neurovascular bundles, and attention to fine details in the surgical technique. Recovery of erections occurs in 68% of preoperatively potent men treated with bilateral nerve-sparing surgery and in 47% of those treated with unilateral nerve-sparing surgery.  相似文献   
112.
Balloon angioplasty (PTA) is an established treatment modality for stenosis in dysfunctional arteriovenous fistulae (AVF), although most studies showing efficacy have been retrospective, uncontrolled, and nonrandomized. In addition, it is unknown whether correction of stenosis not associated with significant hemodynamic, functional, and clinical abnormality may improve survival in AVF. This study was a prospective controlled open trial to evaluate whether prophylactic PTA of stenosis not associated with access dysfunction improves survival in native, virgin, radiocephalic forearm AVF. Sixty-two stenotic, functioning AVF, i.e., able to provide adequate dialysis, were enrolled in the study: 30 were allocated to control and 32 to PTA. End points of the study were either AVF thrombosis or surgical revision due to reduction in delivered dialysis dose. Kaplan-Meier analysis showed that PTA improved AVF functional failure-free survival rates (P = 0.012) with a fourfold increase in median survival and a 2.87-fold decrease in risk of failure. Cox proportional hazard model identified PTA as the only variable associated with outcome (P = 0.012). PTA induced an increase in access blood flow rate (Qa) by 323 (236 to 445) ml/min (P < 0.001), suggesting that improved AVF survival is the result of increased Qa. PTA was also associated with a significant decrease in access-related morbidity by approximately halving the risk of hospitalization, central venous catheterization, and thrombectomy (P < 0.05). This study shows that prophylactic PTA of stenosis in functioning forearm AVF improves access survival and decreases access-related morbidity, supporting the usefulness of preventive correction of stenosis before the development of access dysfunction. It also strongly supports surveillance program for early detection of stenosis.  相似文献   
113.
BACKGROUND: In maintenance haemodialysis patients, daily food intake is changeable; however, its relationship with nutritional status is unexplored. This study aimed to evaluate the isolated, long-term effect of daily nutrient intake on nutritional status in haemodialysis patients. METHODS: We performed a prospective 1-year controlled study in 27 chronic haemodialysis patients, without recognized risk factors for malnutrition. Each day for 1 week, four times in the year, we measured protein nitrogen appearance, and assessed dietary protein (DPI) and energy (DEI) intake from dietary diaries. We compared the nutritional outcome of patients spontaneously reducing nutrient intake below the threshold of 0.8 g/kg body weight/day for DPI and 25 kcal/kg body weight/day for DEI during the week (LOW, n = 8), with controls at adequate nutrient intake (CON, n = 19). An interventional 6-month study was then carried out in LOW to verify the cause-effect relationship. RESULTS: All patients showed a day-by-day reduction of whole nutrient intake during interdialytic period, which was mostly relevant in the third interdialytic day (L3). During the 1-year study, even in the presence of adequate dialysis dose and normal inflammatory indexes, body weight (68.0 +/- 5.5 to 65.8 +/- 5.9 kg), serum albumin (3.96 +/- 0.07 to 3.66 +/- 0.06 g/dl) and creatinine (9.2 +/- 1.1 to 8.1 +/- 0.7 mg/dl) significantly decreased in LOW but not in CON. Diaries evidenced in LOW a reduced number of meals at L3 that was explained by the fear of excessive interdialytic weight gain. During the interventional study, daily DPI and DEI increased at L3; this was associated with a significant increment of body weight, and serum albumin and creatinine levels. CONCLUSIONS: In maintenance haemodialysis patients the persistent, marked reduction of daily nutrient intake, even if limited to a single day of the week, is an independent determinant of reversible impairment of nutritional status.  相似文献   
114.
Development of a reconstructed human skin model for angiogenesis   总被引:4,自引:0,他引:4  
We have previously shown that reconstructed human skin engineered from autologous keratinocytes, fibroblasts, and sterilized donor allodermis stimulates angiogenesis within 5-7 days when placed on well-vascularized wound beds in nude mice. When this reconstructed skin was used clinically in more demanding wound beds, some grafts were lost, possibly due to delayed vascularization. As this reconstructed skin lacks any endothelial cells, our aim in this study was to develop an angiogenic reconstructed skin model in which to explore strategies to improve angiogenesis both in vitro and in vivo. We report that culture of small-vessel human dermal microvascular endothelial cells (HuDMECs) was achieved using magnetic beads coated with an antibody to platelet cell adhesion molecule as a means of purifying the culture. Keratinocytes, fibroblasts, and HuDMECs could be cultured from the same skin biopsy. Initial studies culturing HuDMECs and other sources of endothelial cells with the tissue-engineered skin showed that these cells were capable of slowly entering the dermis under standard culture conditions in vitro. In conclusion, this provides us with a model in which to explore strategies for improving angiogenesis in vitro and also establishes the culture methodologies for the production of reconstructed skin containing autologous keratinocytes, fibroblasts, and endothelial cells.  相似文献   
115.
Radiofrequency (RF)-assisted thermal ablation has been used with increasing frequency for unresectable hepatic tumors. This new approach employs RF energy to coagulate the liver at the hepatic resection line after which hepatic resection is performed with the use of a common scalpel. This procedure was used in three patients with hepatocellular carcinoma and in five patients with colorectal metastasis to the liver. These eight patients underwent a total of two left bisegmentectomies, three segmentectomies, and seven wedge resections. Mean operative time was 220 minutes. A mean of 78 sessions of RF-assisted ablation were required for these resections. Mean blood loss was 46 ml; no device other than RF ablation was required to obtain hemostasis. None of the patients needed a blood transfusion. Preoperative hemoglobin was 12.8 gm/dl and postoperative hemoglobin was 11.3 gm/dl. There were no perioperative deaths. Postoperative complications occurred in two patients: a liver abscess in one and heart failure in the other. The mean hospital stay was 9.4 days. This new approach, integrated with other techniques, reduces blood loss and coagulates the margins of resection during liver surgery. This new technique has two limitations: (1) it cannot be applied near main portal pedicles, and (2) it requires a long operative time. The best indication for this technique is when segmentectomy is required in patients with cirrhosis. Its role in major hepatic resections has yet to be determined. Further progress in the development of thermal ablation techniques and experience gained during the learning curve should help reduce the operative time, thereby improving the safety and efficacy of this procedure. Presented at the Third International Meeting, "Hepatocellular Carcinoma: Eastern and Western Experience," Lodi, Italy, November 21–22, 2002.  相似文献   
116.
Angiogenesis induction and regression in human surgical wounds   总被引:2,自引:0,他引:2  
Angiogenesis in human wound healing is not well characterized, with only sparse information available regarding the maturation and fate of vessels formed as a consequence of human tissue repair. Therefore, this study aimed to establish the temporal profile of angiogenesis in human dermal wounds. Punch biopsies were obtained under local anesthesia from 45 patients following breast surgery. Scars were predominantly between 2 and 52 weeks after surgery but in five patients were > 52 weeks. Control samples were taken from breast skin peroperatively (n = 24). Quantification of vascular density was performed using the Chalkley grid, following antibody staining for platelet endothelial cell adhesion molecule. Vascular patterns, wound cellularity and morphology were also determined. Cumulative microvessel density was increased in all samples when compared to controls (p < 0.05). This was greatest 2 to 24 weeks following surgery 17 (15-21) median (range), decreased thereafter, but remained elevated compared to controls even in the mature scars > 52 weeks. Control tissue showed an ordered morphological arrangement of dermal structures, collagen, and elastic fibers. However, wounding resulted in marked structural distortion for up to 15 weeks. In conclusion, this study shows for the first time the prolonged persistence of both microvessels and cellularity (fibroblastic cells), in addition to structural distortion in human dermal wounds, which is in contrast to previous in vitro and in vivo studies.  相似文献   
117.
Autologous skin grafting is an important method for wound coverage; however, it is an invasive procedure and can cause donor site morbidity. Epidermal grafting (EG) enables epidermal transfer to wounds with minimal donor site morbidity. However, data to date have been heterogeneous. This study aims to synthesise the current evidence on EG for wound healing to establish the efficacy of this surgical technique. A comprehensive search in the MEDLINE, EMBASE and CENTRAL databases was conducted. The endpoints assessed were proportion of wounds healed and mean wound‐healing time. This systematic review was conducted and reported according to the Meta‐Analysis of Observational Studies in Epidemiology (MOOSE) guidelines. We identified 1568 articles, of which seven articles were included in this review – a total of 209 wounds in 190 patients. The mean wound duration was 17·06 weeks (95% CI 8·57–25·55). Of these, 71·5% (95% CI 56·7–84·2) of the wounds achieved complete healing. Mean time for complete wound healing was 5·53 weeks (95% CI 3·18–7·88). The mean donor site healing time was 7·48 days (95% CI 4·83–10·13), with no reported donor site morbidity. The current data are small and lack level 1 evidence.  相似文献   
118.

Purpose

Local tumor ablation (LTA) and partial nephrectomy (PN) represent treatment alternatives for patients diagnosed with small renal mass and both may result in renal function detriments. The aim of the study was to compare renal function detriments after LTA or PN.

Methods

A Surveillance epidemiology and End Results-Medicare-linked retrospective cohort of 2850 T1 kidney cancer patients who underwent LTA or PN was abstracted. Short-term outcomes consisted of 30-day acute kidney injury (AKI) and 30-day dialysis rates. Long-term outcomes consisted of episodes of AKI, mild and moderate–severe chronic kidney disease (CKD), end-stage renal disease, hemodialysis and anemia in CKD. Analyses consisted of propensity score matching, logistic and Cox regression.

Results

After propensity score matching, 1122 patients remained. The 30-day incidence of AKI was 4.6 % after LTA and 9.4 % after PN. In multivariable analyses (MVAs), LTA was associated with a lower AKI rate (OR 0.42; p = 0.001). The 30-day incidence of any dialysis was <2 % after either LTA or PN. In MVA, LTA was not associated with a lower rate of any dialysis (OR 0.43; p = 0.2). At long-term assessment, both the unadjusted and adjusted rates of all six examined end points were not different between LTA and PN (all p > 0.5).

Conclusions

LTA offers short-term protective effect from AKI. The short-term rates of any dialysis treatment are similar after either LTA or PN. At long-term assessment, LTA and PN renal function detriment rates are not different. Concern for long-term functional outcomes should not be a barrier for PN.
  相似文献   
119.
Background  Roentgenographic and functional outcomes of expandable self locking intramedullary nailing and platelet rich plasma (PRP) gel in the treatment of long bone non-unions are reported. Materials and methods  Twenty-two patients suffering from atrophic diaphyseal long bone non-unions were enrolled in the study. Patients were treated with removal of pre-existing hardware, decortication of non-union fragments, and fixation of pseudoarthrosis with expandable intramedullary nailing (Fixion™, Disc’O Tech, Tel Aviv, Israel). At surgery, PRP was placed in the pseudoarthrosis rim. Results  The thirteen-month follow-up showed 91% (20/22 patients) of patients attaining bony union. The average time to union was 21.5 weeks. No infection, neurovascular complication, rotational malalignment, or limb shortening >4 mm were observed. The healing rate of non-unions was comparable to that observed in previous studies but with a lower complication frequency. Conclusions  The combined use of self locking intramedullary nailing and PRP in the management of atrophic diaphyseal long bone non-unions seems to produce comparable results with less complications than previously reported. Further data are warranted to investigate the single contribution of PRP gel and Fixion nail.  相似文献   
120.

Background

Published interim results have shown that fibrin sealant (Tissucol®/Tisseel® Baxter AG, Vienna, Austria) may be effective in preventing anastomotic leaks and internal hernias following laparoscopic Roux-en-Y gastric bypass (LRYGBP). We report the final results of a multicenter, randomized clinical trial evaluating the use of fibrin sealant in LRYGBP.

Methods

Between January 2004 and December 2005, 340 patients aged 21–65 years with a body mass index (BMI) of 40–59 kg/m2 undergoing LRYGBP were randomized (1:1) to two treatment groups: fibrin sealant group (applied to gastrojejunal and jejunojejunal anastomoses and over mesenteric openings), and control group (no fibrin sealant; suture of the mesenteric openings). Operative time, early and late complications, reinterventions, time to oral diet initiation, and length of stay were assessed.

Results

Overall, 320 patients were included into the study: 160 in the control group and 160 in the fibrin sealant group. All patients completed follow-up assessments at 6 and 12 months, and 60.9% completed assessments at 24 months. There were no significant differences between groups with respect to demographics, operative time, oral diet initiation, hospital stay, and BMI reduction at 6, 12, and 24 months. The incidence of anastomotic leak was numerically, but not significantly, greater in the control group. The overall reintervention rate for specific early complications (<30 days) was significantly higher in the control group (p = 0.016). No deaths or conversions to open laparotomy occurred.

Conclusion

The use of fibrin sealant in laparoscopic RYGBP may be beneficial in reducing the reintervention rate for major perioperative (<30 days) complications. Larger studies are needed.  相似文献   
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