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101.
Is a T-tube Necessary after Common Bile Duct Exploration?   总被引:1,自引:0,他引:1  
BACKGROUND: T-tube drainage used to be standard practice after surgical choledocholithotomy, but there is now a tendency in some centers to close the common bile duct (CBD) primarily. This study was designed to review the complications associated with T-tube drainage after CBD exploration and to determine whether primary closure of the bile duct reduces postoperative morbidity. METHODS: A retrospective audit was performed on patients undergoing CBD exploration between July 1997 and March 2007, who were identified from the theatre database of one teaching hospital. Intraoperative findings and postoperative complications were recorded from the clinical notes. RESULTS: During the study period, 158 patients (97 women; median age 65 (range, 25-90) years) underwent CBD exploration. A T-tube was inserted in 91 patients (group I) and the CBD was closed primarily in 67 (group II). One or more biliary complications occurred in 26 patients (16.5%): 20 (22.0%) in group I and 6 (8.9%) in group II (p = 0.03). In group I, 15 had a biliary leak (3 needed reoperation), 2 had accidental slippage of the tube, 2 an entrapped T-tube, and 1 a retained stone. In group II, six patients had biliary leakage, two of whom were re-explored. Six patients in group I also had peritubal infection, necessitating the use of antibiotics. There were three deaths: two in group I (1 T-tube-related) and 1 in group II (p = 1, not significant). CONCLUSION: There is a lower biliary complication rate associated with primary closure of the CBD than after T-tube drainage.  相似文献   
102.
Objectives In this study, we try to evaluate the efficacy and safety of holmium lasers for treatment of ureteric stones in patients with renal impairment or obstructive anuria. Patients and methods Twenty-six patients were included in this study, of which 20 patients presented with elevated blood urea and serum creatinine (2.1–7.6 mg%), and six patients presented with calcular anuria (mean serum creatinine 22 mg%). None of the patients had a ureteric stent or nephrostomy tube before the ureteroscopy. All patients were treated with holmium laser. A stone basket or grasper was used to remove significant stone fragments at the end of the procedure in seven patients. In these seven patients, ureteric stents were placed at the end of the procedure. Results All patients were free of any stone fragments at 1 week and at 3 months postoperatively. In all patients, including the six with obstructive anuria, the renal impairment resolved or improved as evidenced by normalization or fall in blood urea and creatinine. Thus, in this small group of uremic patients, the success rate for treatment of ureteral stone was 100%. Conclusions A holmium laser is a safe and effective modality of ureteroscopic lithotripsy in patients with significant renal impairment or even obstructive anuria. The use of holmium laser with ureteroscopy may be considered in this group of patients as long as the general condition of the patient permits the safe administration of anesthesia.  相似文献   
103.
Bone reinnervation after fracture: a study in the rat.   总被引:11,自引:0,他引:11  
Reinnervation after tibial fracture in the rat was studied by analyzing the occurrence of growth-associated protein 43 (GAP-43), a marker for regenerating nerve fibers, and protein gene product 9.5 (PGP-9.5), a marker for mature nerve fibers, by immunohistochemistry. At 3 days postfracture, GAP-43--immunoreactive nerve fibers were first observed in the fracture hematoma and periosteum. At 7 days postfracture, abundant sprouting of GAP-43--positive fibers was seen in the callus, hyperplastic periosteum, and edge of fibrocartilage. In the latter region, the nerve fibers were nonvascular, showing dense ramifications and terminal sprouting close to chondroid cells. At 14 days and 21 days postfracture, many GAP-43--positive fibers were still sprouting into the fibrocartilage and new woven bone. Fine varicose GAP-43--positive fibers also were present in the bone marrow. In contrast to GAP-43, PGP-9.5-positive nerve fibers were observed only occasionally at 3 days postfracture but gradually increased in number from day 14 to 21. Our study shows that intense nerve regeneration occurs in early fracture healing partly unrelated to neovascularization. Considering that neuronal mediators have been shown to participate in local bone formation and resorption, the nerve regeneration observed may prove to be essential for delivery of neuronal mediators required for normal callus formation and/or neovascularization.  相似文献   
104.
105.
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   
106.

Background

The transanal pull-through has become the standard operation for Hirschsprung's disease in many pediatric surgical centers. Over the past 8 years, we have modified our technique by leaving a short—rather than a long—rectal cuff and by doing routine intraabdominal colonic biopsies through an umbilical incision before beginning the anal dissection. The aim of this study was to determine if these modifications have changed the outcome for children undergoing this operation.

Methods

A retrospective cohort study of all patients who underwent transanal pull-through by a single surgeon between 1997 and 2005 was conducted.

Results

There were 23 children who had a long cuff (10-15 cm) and 22 who had a short cuff (<2 cm). The short cuff group tended to be younger (25 ± 23 vs 139 ± 67 days; P < .05) and smaller (3.5 ± 0.7 vs 6.0 ± 2.7 kg; P < .05) at the time of surgery. The operating time was shorter (167 vs 186 minutes; P = .05) in the short cuff group. Outcomes were improved in the short cuff group, as evidenced by decreased hospital stay (1.9 ± 0.6 vs 2.7 ± 0.9; P < .05), decreased incidence of enterocolitis (9% vs 30%; P = .1), and lower incidence of narrowing requiring daily dilatations (5% vs 30%; P < .05). Preliminary colonic biopsy was performed on 18 of the 45 patients. This had no significant effect on narcotic use (66% vs 70%; P = .8) and did not increase operating time (174 ± 31 vs 179 ± 34 minutes; P = .6). Hospital stay was shorter in the umbilical biopsy group (1.9 ± 0.6 vs 2.6 ± 0.9 days; P = .006).

Conclusion

Results of the transanal pull-through have improved likely as a result of a combination of experience and use of a shorter rectal muscular cuff. The use of a preliminary colonic biopsy through an umbilical incision has not increased postoperative pain, prolonged operative time, or lengthened hospital stay.  相似文献   
107.
Objective: To determine the clinical presentations of alopecia areata in children as well as the frequency of associated disorders. Design: Cross-sectional study. Place and Duration of Study: Department of Dermatology, Ziauddin University Hospital, KDLB Campus, Karachi during the calendar years 2005 and 2006. Patients and Methods: Children of either gender suffering from alopecia areata, upto 15 years of age, who fulfilled the selection criteria were included in the study. Only freshly registered cases were studied. Severity of the disease was graded as mild, moderate and severe disease, and other clinical patterns including alopecia totalis, alopecia universalis and ophiasis. Hematological and biochemical profile was evaluated. Chi-square test was applied for statistical analysis in order to determine p-value using the percentages of variables. Results: One hundred and fourteen patients comprising 54 males (47%) and 60 females (53%), aged 4 upto 15 years, the mean age being 9.1 years, were enrolled. Family history of alopecia areata was positive in 11 patients (10%). Fifty nine patients (51%) were of age 6-10 years, 39 patients (35%), aged 11-15 years, and 16 (14%) were of age below 5 years. Mild alopecia areata (41%, p < 0.05) was the most common presentation followed by moderate disease (31%, p < 0.05), severe alopecia (17%, p < 0.05), alopecia totalis (7%, p < 0.05), alopecia universalis (2.7%, p=0.05) and ophiasis (1.7%, p=0.05). Nail changes were found in 40 patients (35%, p < 0.05). Definite evidence of atopy was obtained in 23 patients (20%, p< 0.05). The autoimmune disorders associated with alopecia areata included: hypothyroidism (4.3%), vitiligo (3.5%), psoriasis (1.8%), systemic lupus erythematosus (SLE 0.9%), hypoparathyroidism (0.9%) and diabetes mellitus (0.9%). Conclusion: The spectrum of childhood alopecia areata ranges from mild, moderate and severe alopecia, ultimately to alopecia totalis, alopecia universalis and ophiasis. Nail changes as well as atopy and autoimmune disorders are the associated disorders.  相似文献   
108.
Background The achievements in short-term graft survival since the introduction of cyclosporine (CsA) have not been matched by improvements in long-term graft function. Chronic allograft nephropathy (CAN) remains the second most common cause of graft attrition over time, after patient mortality. We aimed to evaluate the long-term results of azathioprine vs CsA in live-donor kidney transplantation in a prospective randomized study. Methods We studied 475 renal transplant recipients who had had transplantations performed at the Urology and Nephrology Center, Mansoura University, before 1988 and who had received a primary immunosuppressive protocol consisting of either steroid and azathioprine (steroid/Aza; group 1, 300 patients) or steroid and CsA (steroid/CsA; group 2, 175 patients). Only adult primary renal transplant recipients aged between 18 and 60 years and with one haplotype HLA mismatch were included. All patients received kidneys from living-related donors, with previous donor nonspecific blood transfusions. The study was based on the long-term follow-up data of these renal transplant recipients. Comparative analyses included patient and graft survival rates, condition at last follow up, rejection (acute and chronic), and graft function (serum creatinine and creatinine clearance). Results The overall frequency of acute rejection episodes was not significantly different between the two groups. Graft survival rates were: group 1 vs group 2, 69% vs 58% at 5 years, and 52% vs 36% at 10 years, but at 20 years, graft survival rates had declined to 26% and 24%. No significant differences were encountered between the two groups regarding post-transplant malignancies, diabetes mellitus, hepatic impairment, or serious bacterial infections. Conclusions From this study we can conclude that the long-term result of historical conventional therapy (steroid/Aza) without induction therapy is effective for living-donor kidney transplants. In spite of the comparable graft function for the two groups, the steroid/CsA group experienced more hypertension, as well as many adverse reactions to CsA. Nowadays, since the introduction of induction therapy and the utilization of newer maintenance immunosuppressive agents – such as mycophenolate mofetil (MMF) and rapamycin – it is possible to achieve an excellent calcineurin inhibitors (CNI)-free regimen.  相似文献   
109.
OBJECTIVE: Post-proliferative chondrocytes in growth cartilage are present in two forms, light and dark cells. These cells undergo hypertrophy and die by a mechanism that is morphologically distinct from apoptosis, but has not been characterized. The aims of the current study were to document the ultrastructural appearance of dying hypertrophic chondrocytes, and to establish a culture system in which the mechanism of their death can be examined. DESIGN: Growth cartilage from fetal and growing postnatal horses was examined by electron microscopy. Chondrocytes were isolated from epiphyseal cartilage from fetal horses and grown in pellet culture, then examined by light and electron microscopy, and quantitative polymerase chain reaction. RESULTS: In tissue specimens, it was observed that dying dark chondrocytes underwent progressive extrusion of cytoplasm into the extracellular space, whereas light chondrocytes appeared to disintegrate within the cellular membrane. Pellets cultured in 0.1% fetal calf serum (FCS) contained dying light and dark chondrocytes similar to those seen in vivo. Transforming growth factor-beta1 or 10% FCS increased the proportion of dark cells and induced cell death. Triiodothyronine increased the differentiation of dark and light cells and induced their death. Dark cells were associated with higher levels of matrix metalloproteinase-13 expression than light cells, and light cells were associated with higher levels of type II collagen expression. CONCLUSIONS: Light and dark hypertrophic chondrocytes each undergo a distinctive series of non-apoptotic morphological changes as they die. Pellet culture can be used as a model of the two forms of physiological death of hypertrophic chondrocytes.  相似文献   
110.
Magheli A  Rais-Bahrami S  Humphreys EB  Peck HJ  Trock BJ  Gonzalgo ML 《The Journal of urology》2007,178(5):1933-7; discussion 1937-8
PURPOSE: Increased age has been suggested to predict worse clinical outcomes in patients with prostate cancer. An explanation that was proposed for this observation is that it is due to inherent differences in the biological properties of prostate cancer in older men. Stage migration, prostate specific antigen and prostate biopsy pathology are variables that may confound the interpretation of age as an independent prognosticator of outcomes following radical prostatectomy. MATERIALS AND METHODS: Matched pairs analysis was performed comparing the 3 age cohorts 46 to 55, 56 to 65 and older than 65 years to a cohort of 435 patients who were 45 years or younger based on propensity scores calculated with all known preoperative variables. Postoperative clinical and pathological characteristics were compared among the 4 matched age cohorts. A Cox hazards model was used to compare time to prostate specific antigen recurrence across the different age cohorts and the actuarial risk of recurrence was calculated using Kaplan-Meier and log rank survivor analyses. RESULTS: Younger patients showed lower grade disease (p <0.001), and lower rates of positive surgical margin rates (p = 0.035) and extraprostatic extension (p <0.001) but they did not have higher rates of lymph node involvement (p = 0.85) or seminal vesicle invasion (p = 0.56). Kaplan-Meier analysis showed no significant differences in biochemical recurrence across the age cohorts (log rank 0.38). On multivariate analysis prostatectomy Gleason score, pathological stage, positive surgical margins (each p <0.001) and preoperative prostate specific antigen (p = 0.04) were independently predictive of biochemical recurrence. CONCLUSIONS: We report that increased age is not associated with worse biochemical outcomes following radical prostatectomy and it should not be considered an independent prognosticator for disease recurrence. Rather, age is a surrogate for known predictors of biochemical recurrence following surgery.  相似文献   
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