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101.
The implications of lighted ureteral stenting in laparoscopic colectomy.   总被引:1,自引:0,他引:1  
OBJECTIVE: The placement of indwelling ureteral catheters during colorectal surgery has been recommended for prevention of ureteral injuries. With the advent of laparoscopic colectomy (LCo), the role of preoperative placement of lighted ureteral stents (LUS) has also become commonplace. We sought to evaluate the value of lighted ureteral stent placement in laparoscopic colectomy. METHODS: Sixty-six patients underwent LCo with LUS inserted preoperatively. Stents were removed in the immediate postoperative period. Two surgeons performed all the colectomies; 32 patients were males and 34 were females. Fifty patients underwent sigmoid colectomy, 4 had abdominoperineal resection, 4 had right colectomy, and 1 each had transverse or subtotal colectomy. Eighteen patients had a diagnosis of cancer, 34 had diverticular disease, and 14 had neoplastic polyps. Forty patients had bilateral and 26 had unilateral stent placement. A review of the incidence of ureteral injuries, hematuria, and anuria as the cause of acute renal failure was accomplished, comparing the unilateral and bilateral stented groups. RESULTS: One (1.5%) patient suffered a left ureteral laceration during sigmoid colectomy. This was managed successfully with stent reinsertion. Sixty-five (98.4%) patients had gross hematuria lasting 2.93 days (1 to 6 days). The cost of bilateral stent placement was $1,504.32. A statistically significant difference occurred in the duration of hematuria (days) between patients who had unilateral (2.5 +/- 0.82) and bilateral stent placement (3.37 +/- 1.05), (P < 0.001). Four patients suffered from anuria, 2 required renal support needing hemodialysis for 3 to 6 days, 3 (75%) had bilateral stents, and 1 (25%) had a unilateral stent. CONCLUSIONS: We recommend the placement of lighted ureteral stents as a valuable adjunct to laparoscopic colectomy to safeguard ureteral integrity. Transient hematuria is common but requires no intervention. Reflux anuria occurs infrequently and is reversible.  相似文献   
102.
Bone disease is a frequently reported complication in primary biliary cirrhosis (PBC), but its pathogenesis is poorly understood. Calcium malabsorption has been considered as an important contributing factor. Ursodeoxycholic acid (UDCA) is the treatment of choice in PBC, improving survival, but its effect on calcium absorption is unknown. In this study, we have measured fractional calcium absorption, using a single isotope method, in a group of female PBC patients (median age: 60 years, range: 46–78 years) and age-matched female controls (median age: 58 years, range: 36–74). Bone mineral density (BMD) in PBC patients was significantly lower than age-matched controls (g/cm2± SEM; lumbar spine: controls 1.139 ± 0.028, PBC patients 1.004 ± 0.026, p= 0.0028; femoral neck: controls 0.944 ± 0.034, PBC patients 0.819 ± 0.023, p = 0.0032). Twenty two PBC patients, who were not vitamin D-deficient, were off and on UDCA for ~1 month and ~8 weeks, respectively. Fractional calcium absorption in PBC patients prior to UDCA treatment (mean ± SEM, 33.8 ± 2.6%) was significantly lower than controls (52.0 ± 2.4%, p<0.001). Following UDCA therapy, fractional calcium absorption increased significantly (Off UDCA: 33.1 ± 2.6%, On UDCA: 36.6 ± 2.5%, p<0.0058). Osteocalcin levels were significantly raised in the PBC group (mean ± SEM, ng/ml, 41.4 ± 2.02) compared to controls (31.1 ± 2.64, p= 0.002). There were no differences in parathyroid hormone (PTH) or 25-hydroxyvitamin D levels between these two groups or following UDCA therapy. In conclusion, we found that PBC patients display low spinal and femoral neck BMD, reduced fractional calcium absorption, and elevated plasma osteocalcin. The calcium malabsorption is corrected partially by UDCA therapy. Long-term studies are required to determine whether this effect can be sustained, and whether a sustained increase in fractional calcium absorption can translate into a favorable change in bone strength in patients with PBC. Received: 27 November 2001 / Accepted: 11 April 2002  相似文献   
103.
Reports on metastatic differentiated carcinoma in endemic goiter regions are scarce. The aim of this study was to look into the clinicopathological profile and outcome of patients with metastatic differentiated thyroid carcinoma (DTC) of endemic origin. This was a retrospective study of 28 cases of metastatic DTC out of a total of 140 DTC patients managed between 1990 and June 1999. Demographic data, clinicopathological profile, operative and radioiodine ablation therapy details, and follow-up findings were noted. The overall incidence of distant metastases in our series was 20%. Mean age was 48.5 +/- 12.8 years (32.1%patients were < 45 years). Most metastases were detected synchronously (85.7%) and were multiple, with the skeletal system being the commonly affected site. Out of 22 cases having skeletal metastases, 6 patients were young (< 45 years). Though most patients with skeletal metastases had follicular carcinoma (FTC), 4 cases had papillary thyroid cancer (PTC). Near total or total thyroidectomy was done in 26 cases. Sixteen patients required regional lymph node dissection. Resection of metastases was performed in 9 cases.Histopathological diagnosis was PTC, FTC, and poorly differentiated carcinoma in 32.1%, 50.0%, and 17.9% of cases, respectively. Most patients had good symptomatic palliation following administration of I131 therapy. In 17.9% of cases there were locoregional recurrences. There was an overall 28.6% mortality. Two patients expired in the perioperative period. Six others died in follow-up (all within 3-9 months). In contrast to iodine sufficient regions, the incidence of metastases was high; the majority of cases had synchronous, symptomatic skeletal metastases. Skeletal metastases were not infrequent even in cases of PTC and in young patients. One-third of the cases were young. Though survival was poor despite aggressive management, significant symptomatic palliation could be achieved in most cases.  相似文献   
104.
105.
Gradient dynamical systems with discontinuous righthand sides are designed using Persidskii-type nonsmooth Lyapunov functions to work as support vector machines (SVMs) for the discrimination of nonseparable classes. The gradient systems are obtained from an exact penalty method applied to the constrained quadratic optimization problems, which are formulations of two well known SVMs. Global convergence of the trajectories of the gradient dynamical systems to the solution of the corresponding constrained problems is shown to be independent of the penalty parameters and of the parameters of the SVMs. The proposed gradient systems can be implemented as simple analog circuits as well as using standard software for integration of ODEs, and in order to use efficient integration methods with adaptive stepsize selection, the discontinuous terms are smoothed around a neighborhood of the discontinuity surface by means of the boundary layer technique. The scalability of the proposed gradient systems is also shown by means of an implementation using parallel computers, resulting in smaller processing times when compared with traditional SVM packages.  相似文献   
106.
Acute kidney injury (AKI) occurs commonly after pediatric cardiac surgery and associates with poor outcomes. Biomarkers may help the prediction or early identification of AKI, potentially increasing opportunities for therapeutic interventions. Here, we conducted a prospective, multicenter cohort study involving 311 children undergoing surgery for congenital cardiac lesions to evaluate whether early postoperative measures of urine IL-18, urine neutrophil gelatinase-associated lipocalin (NGAL), or plasma NGAL could identify which patients would develop AKI and other adverse outcomes. Urine IL-18 and urine and plasma NGAL levels peaked within 6 hours after surgery. Severe AKI, defined by dialysis or doubling in serum creatinine during hospital stay, occurred in 53 participants at a median of 2 days after surgery. The first postoperative urine IL-18 and urine NGAL levels strongly associated with severe AKI. After multivariable adjustment, the highest quintiles of urine IL-18 and urine NGAL associated with 6.9- and 4.1-fold higher odds of AKI, respectively, compared with the lowest quintiles. Elevated urine IL-18 and urine NGAL levels associated with longer hospital stay, longer intensive care unit stay, and duration of mechanical ventilation. The accuracy of urine IL-18 and urine NGAL for diagnosis of severe AKI was moderate, with areas under the curve of 0.72 and 0.71, respectively. The addition of these urine biomarkers improved risk prediction over clinical models alone as measured by net reclassification improvement and integrated discrimination improvement. In conclusion, urine IL-18 and urine NGAL, but not plasma NGAL, associate with subsequent AKI and poor outcomes among children undergoing cardiac surgery.  相似文献   
107.
The latest revision of the International Standards for the Neurological Classification of Spinal Cord Injury (ISNCSCI) was available in booklet format in June 2011, and is published in this issue of the Journal of Spinal Cord Medicine. The ISNCSCI were initially developed in 1982 to provide guidelines for the consistent classification of the neurological level and extent of the injury to achieve reliable data for clinical care and research studies. This revision was generated from the Standards Committee of the American Spinal Injury Association in collaboration with the International Spinal Cord Society's Education Committee. This article details and explains the updates and serves as a reference for these revisions and clarifications.  相似文献   
108.
Total Thyroidectomy for Benign Thyroid Disorders in an Endemic Region   总被引:21,自引:2,他引:21  
Total thyroidectomy is increasingly being accepted as a treatment of choice for differentiated thyroid cancer. However, because of presumed increased morbidity associated with this procedure, it is still not considered a viable option for management of benign thyroid disorders. To assess the safety and efficacy of total thyroidectomy for management of benign thyroid disorders, we analyzed our data from 127 total thyroidectomies performed for benign thyroid disorders. Demographic details, biochemical findings, indications for operation, specimen weight, and complications were noted. Among these patients, 52 had a toxic goiter and 75 had a nontoxic goiter. The mean duration of the goiters being present was 6.08 ± 6.06 years (0.9–26.0 years), and the mean weight of the specimens was 136.88 ± 120.68 g. The incidence of occult malignancy was 6.3% (n= 8), and those of permanent hypothyroidism and permanent recurrent laryngeal nerve palsy were 1.6% and 0.8%, respectively. Total thyroidectomy should be considered a treatment of choice for multinodular goiter and Graves' disease in a setting of palpable nodule(s) or ophthalmopathy (or both). It is particularly relevant in endemic regions where patients present with a long-standing, large nodular goiter with virtually no normal thyroid tissue. Reoperation for recurrent goiter in such a setting would be fraught with distressing complications.  相似文献   
109.
PURPOSE: It is widely reported that a prostate biopsy gun needle advances 0.5 cm and then obtains the subsequent 1.5 cm of tissue. Based on this presumed skip area it is recommended that the needle tip must be placed 0.5 cm from the capsule before firing to obtain the capsule with the specimen. Contrary to this longstanding recommendation, in our experience we have observed that there is no such skip area. We determined the actual content of a needle core by obtaining biopsies from an apple model with clinical correlation to validate our findings. MATERIAL AND METHODS: Using 3 types of spring-loaded biopsy needles we obtained 24 cores from an apple. We placed the biopsy needle tip directly adjacent to the capsule before firing the biopsy gun. Visual inspection of each biopsy core was done to confirm the presence or absence of the capsule (red apple peel). RESULTS: All cores had confirmed presence of the apple peel, confirming the absence of a skip area in the first 0.5 cm. CONCLUSIONS: Using spring-loaded biopsy guns we observed in an apple model that the capsule is obtained when the biopsy needle tip is placed directly adjacent to the capsule. Urologists placing the biopsy needle tip directly on the capsule in line with the projected trajectory will obtain the prostatic capsule in the specimen and should not withdraw the needle unless the gland depth is short enough so that there is risk of firing past the gland.  相似文献   
110.
Carrizo GJ  Wu R  Cui X  Dwivedi AJ  Simms HH  Wang P 《Surgery》2007,141(2):245-253
BACKGROUND: Recent studies have shown that adrenomedullin (AM) and AM-binding protein-1 (AMBP-1) possess anti-inflammatory properties in sepsis. We hypothesized that administration of AM/AMBP-1 after gut ischemia-reperfusion (I/R) downregulates inflammatory cytokines and attenuates tissue injury. METHODS: Male Sprague-Dawley rats (275-325 g) were used. Gut ischemia was induced by placing a microvascular clip across the superior mesenteric artery (SMA) for 90 minutes. Upon release of the SMA clamp, the animals were treated by AM (12 microg per kilogram of body weight) and AMBP-1 (40 microg per kilogram of body weight) in combination, or vehicle (1 mL 0.9% NaCl) over 30 minutes via a femoral vein catheter. The animals undergoing sham operation or ischemia for 90 minutes only, did not receive AM/AMBP-1 treatment. At 60 minutes after the completion of the treatment (ie, 90 minutes after reperfusion), blood samples were collected. Plasma AM and AMBP-1 were measured by radioimmunoassay and Western blot analysis, respectively. Serum levels of TNF-alpha, interleukin (IL)-1beta, IL-6, IL-10, transaminases (ie, alanine aminotransaminase, aspartate aminotransaminase), lactate, and creatinine were determined with the use of enzyme-linked immunosorbent assay and other standard methods. In additional groups of animals, the 10-day survival rate was recorded after gut I/R. RESULTS: Ischemia alone was sufficient to downregulate both AM and AMBP-1. Unlike AMBP-1 that remained decreased, AM levels increased significantly after reperfusion. I/R but not ischemia alone significantly increased serum levels of inflammatory cytokines. Moreover, I/R-induced tissue injury was evidenced by increased levels of transaminases, lactate, and creatinine. Administration of AM/AMBP-1 after ischemia, however, markedly reduced cytokine levels, attenuated tissue injury, and improved survival. CONCLUSIONS: AM/AMBP-1 may be a novel treatment to attenuate the reperfusion injury after gut ischemia.  相似文献   
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