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71.
Acute injury to the central nervous system initiates a series of biochemical events that cause secondary tissue damage. The accumulation of excessive concentrations of glutamate in the extracellular space causes excitotoxic damage, and is incriminated as a mediator of this secondary tissue damage. The aim of this study was to measure the concentration of glutamate in cerebrospinal fluid (CSF) obtained from the cerebellomedullary cistern and lumbar subarachnoid space in dogs with acute and chronic compressive injuries of the cervical and thoracolumbar spinal cord, and to correlate the glutamate concentration with injury severity. The results demonstrate that focal injuries of the spinal cord do not affect the glutamate concentration in CSF taken from the cerebellomedullary cistern. However, dogs with severe, acute thoracolumbar disc herniations have two- to 10-fold increases in glutamate concentration in their lumbar CSF at intervals of >12 h after injury. Moreover, the severity of their clinical signs is directly related to the glutamate concentration. Dogs with chronic compressive thoracolumbar lesions have a two-fold elevation of CSF glutamate concentration, suggesting that excitotoxicity may also be a component of chronic spinal cord compression.  相似文献   
72.
A previous study had shown an increased prevalence (83%) of diverticula among patients with autosomal dominant polycystic kidney disease (ADPKD) with end-stage renal disease (ESRD) compared with other ESRD patients without ADPKD (32%). Others have also suggested an increased risk for diverticular complications in renal transplant recipients with ADPKD. To determine whether there was an increased occurrence of diverticula among non-ESRD patients with ADPKD, we studied 55 patients with ADPKD who were not receiving renal replacement therapy compared with 12 unaffected family members (non-ADPKD) and 59 random patients who had undergone barium enemas (control [C]). No study patient had a history of diverticular disease. All patients underwent a double-contrast barium enema after administration of glucagon. The occurrence, number, location, and size of diverticula were noted. There was no significant difference among the three groups in regard to sex (men: ADPKD, 42% versus non-ADPKD, 42% versus C, 37%) or age (ADPKD, 49.3 +/- 0.7 versus non-ADPKD, 51.2 +/- 2.1 versus C, 49 +/- 1 years). There was no significant difference in the percentage of patients with diverticula (ADPKD, 47% versus non-ADPKD, 58% versus C, 59%), the percentage with only right-colon diverticula (ADPKD, 5% versus non-ADPKD, 17% versus C, 5%), the mean number of diverticula in patients with diverticulosis (ADPKD, 13.8 versus non-ADPKD, 7.9 versus C, 9.9 diverticula), or the size of the largest diverticula (ADPKD, 9.5 versus non-ADPKD, 10.4 versus C, 10.5 mm). There was no significant difference in these variables between the patients with ADPKD with a creatinine clearance greater than 70 mL/min/1.73 m(2) (n = 25) or less than 70 mL/min/1.73 m(2). This study does not show the greater prevalence of diverticular disease in non-ESRD patients with ADPKD compared with the general population. Thus, patients with ADPKD need not be considered at greater risk for diverticular disease than the general population.  相似文献   
73.
OBJECTIVE: We sought to determine the impact of the addition of Dor fundoplication on the incidence of postoperative gastroesophageal reflux (GER) after Heller myotomy. SUMMARY BACKGROUND DATA: Based only on case series, many surgeons believe that an antireflux procedure should be added to the Heller myotomy. However, no prospective randomized data support this approach. PATIENTS AND METHODS: In this prospective, randomized, double-blind, institutional review board-approved clinical trial, patients with achalasia were assigned to undergo Heller myotomy or Heller myotomy plus Dor fundoplication. Patients were studied via 24-hour pH study and manometry at 6 months postoperatively. Pathologic GER was defined as distal esophageal time acid exposure time greater than 4.2% per 24-hour period. The outcome variables were analyzed on an intention-to-treat basis. RESULTS: Forty-three patients were enrolled. There were no differences in the baseline characteristics between study groups. Pathologic GER occurred in 10 of 21 patients (47.6%) after Heller and in 2 of 22 patients (9.1%) after Heller plus Dor (P = 0.005). Heller plus Dor was associated with a significant reduction in the risk of GER (relative risk 0.11; 95% confidence interval 0.02-0.59; P = 0.01). Median distal esophageal acid exposure time was lower in the Heller plus Dor (0.4%; range, 0-16.7) compared with the Heller group (4.9%; range, 0.1-43.6; P = 0.001). No significant difference in surgical outcome between the 2 techniques with respect to postoperative lower-esophageal sphincter pressure or postoperative dysphagia score was observed. CONCLUSIONS: Heller Myotomy plus Dor Fundoplication was superior to Heller myotomy alone in regard to the incidence of postoperative GER.  相似文献   
74.
BACKGROUND: Traditional management of pyloric stenosis has consisted of open pyloromyotomy during which the surgeon is able to palpate and determine whether the hypertrophied pylorus has been completely divided. During the last decade, laparoscopic pyloromyotomy has become an increasingly popular approach for this condition. The purpose of this study was to determine whether there is an effective pyloromyotomy length that will allow the surgeon to feel confident that a complete pyloromyotomy was performed with the laparoscopic approach. METHODS: All infants undergoing laparoscopic pyloromyotomy from October 1999 through October 2003 at a single institution were retrospectively studied. Clinical variables collected included the patient's age, gender, electrolyte status on admission, the elapsed time from admission to operation, ultrasonographic dimensions of the hypertrophied pylorus, operative time, the length of the pyloromyotomy performed, the time to initial and to full feedings, and the duration of the postoperative hospitalization. RESULTS: One hundred seventy-one patients comprised the study group. The age (mean +/- standard deviation) at the time of operation was 5.2 +/- 2.8 weeks. The mean preoperative ultrasonic measurements for both pyloric thickness and pyloric length were 4.3 +/- 0.7 mm and 19.5 +/- 2.8 mm, respectively. The average pyloromyotomy incision length for this entire group was 1.9 +/- 0.21 cm. The mean operative time was 23.5 +/- 8.3 minutes. There were no mucosal perforations, no conversions to an open procedure, and no evidence for an incomplete pyloromyotomy. CONCLUSIONS: Laparoscopic pyloromyotomy is a safe and effective technique for infants with pyloric stenosis. A pyloromyotomy incision length of approximately 2 cm appears to be an effective measure of a complete pyloromyotomy.  相似文献   
75.
This article presents the case of a 42-year-old man who presented with superior vena cava (SVC) syndrome due to fibrosing mediastinitis with multiple failed attempts at recanalization. We initially treated him with unilateral sharp needle recanalization of the right innominate vein into the SVC stump followed by stenting. Although his symptoms improved immediately, they did not completely resolve. Six months later, he returned with worsening symptoms, and venography revealed in-stent restenosis. The patient requested simultaneous treatment on the left side. The right stent was dilated, and a 3-cm-long occlusion of the left innominate vein was recanalized, again using sharp needle technique, homing into the struts of the right-sided stent. Following fenestration of the stent, a second stent was deployed from the left side into the SVC, and the two Y limbs were sequentially dilated to allow a true bifurcation anatomy (figure). The patient had complete resolution of his symptoms and continues to do well 6 months later.  相似文献   
76.
BackgroundThe need for interval appendectomy after nonoperative management of a perforated appendicitis is being questioned owing to recent studies that estimated recurrence rates as low as 5% because of obliteration of the appendiceal lumen. We review our experience with interval appendectomy in this subset of patients to determine the postoperative outcomes and luminal patency rates.MethodsA retrospective review was conducted of all children treated nonoperatively for a perforated appendicitis followed by elective interval appendectomy during the past 10 years. The data collected included initial hospitalization, convalescence period, perioperative course, and luminal patency rates.ResultsA total of 128 patients were identified, of whom 55% were male. Their mean ± SD age was 9.1 ± 4.2 years. The mean interval from the initial presentation to appendectomy was 65.9 ± 20.3 d. All but 2 of the patients underwent laparoscopic appendectomy with 3 conversions to open surgery. The mean operative time was 43.6 ± 19.2 min. The complication rate was 9%, including 1 postoperative abscess, 1 reoperation for bleeding, and 1 readmission for Clostridium difficile infection. Six patients had a superficial wound infection, and 2 patients underwent outpatient procedures for suture granuloma. No risk factors for complications were identified. Of the specimens, 16% had obliterated lumens.ConclusionsMajor postoperative morbidity for interval appendectomy after a perforated appendicitis is low and should not be a deterrent in offering interval appendectomy to this subset of patients.  相似文献   
77.
OBJECTIVE: To evaluate the ability of positron emission tomography (PET) with 18F-fluoro-2-deoxy-D-glucose (18F-FDG) to determine noninvasively axillary lymph node status in patients with breast cancer. BACKGROUND: The presence of axillary lymph node metastasis is the most important prognostic factor in women with breast cancer. It signifies the presence of occult metastatic disease and indicates the need for adjuvant therapy. The only reliable way in which this important prognostic information may be obtained is by performing axillary dissection, which may be associated with significant complications and delay in discharge from the hospital. PET with 18F-FDG can visualize primary cancers in the breast and metastatic tumor deposits. METHODS: Fifty patients with untreated breast cancer had clinical examination of their axilla performed (graded as positive or negative), followed by PET of the axilla and midthorax. PET data were analyzed blindly and graded as positive or negative, depending on the presence or absence of axillary nodal metastases. Cytopathologic assessment of the axillary nodes was carried out within 1 week of PET, by fine-needle aspiration cytology in 5 patients and axillary dissection in 45; the excised specimens were examined by a single pathologist. RESULTS: The overall sensitivity of PET in 50 patients was 90% and the specificity was 97%. Clinical examination of the same patients had an overall sensitivity of 57% and a specificity of 90%. In the 24 patients with locally advanced breast cancer (T3, T4, TxN2), PET had a sensitivity of 93% and a specificity of 100%. In T1 tumors (seven patients), the sensitivity and specificity were 100%. PET had a high predictive value (>90%) and accuracy (94%) in staging the axilla. CONCLUSIONS: PET is a sensitive and specific method of staging the axilla in patients with breast cancer. It may obviate the need for axillary surgery in women with small primary tumors, define the women likely to benefit from axillary dissection, or allow radiotherapy to be substituted for surgery, particularly in post-menopausal women.  相似文献   
78.

Purpose

Previous work demonstrated that prior MRSA infection [MRSA(+)] is associated with 30-day surgical site infection (SSI) following ventral hernia repair (VHR). We aimed to determine the impact of MRSA(+) on long-term wound outcomes after VHR.

Participants

A retrospective cohort study was performed at a tertiary center between July 11, 2005, and May 18, 2012, of patients undergoing elective VHR with class I wounds. Patients with documented preoperative MRSA infection at any site (urinary, bloodstream, SSI, etc.) were considered MRSA(+). Primary outcome was 2-year surgical site occurrence (SSO), defined as SSI, cellulitis, necrosis, nonhealing wound, seroma, hematoma, dehiscence, or fistula. SSOs were subdivided into those that required procedural intervention (SSOPI) and those that did not.

Results

Among 632 patients, 46 % were female with average age 53 ± 13 years. There were 368 SSOs in 193 patients (31 %); an SSOPI occurred in 9.8 % (n = 62). The most common SSOs were cellulitis (91/632), seroma (91/632), and serous drainage (58/632). The rate of 2-year SSO was higher with MRSA(+) compared to those without (46 vs. 29 %, p = 0.023), attributed to increased soft tissue necrosis, purulent drainage, serous drainage, cellulitis, and fistula. In multivariable analysis, MRSA(+) was not associated with 2-year SSO (HR 1.5, 95 % CI 0.91–2.55, p = 0.113); factors associated with SSO included obesity, immunosuppression, mesh repair, and operative times.

Conclusions

This study is the first to evaluate long-term SSOs and SSOPIs after VHR, highlighting the importance of long-term follow-up. Though not independently associated with SSOs, MRSA(+) may be a marker of hernia complexity.
  相似文献   
79.
OBJECTIVE: This study investigated the contributions of physical fitness and body composition to 24-h fat oxidation in adults under sedentary conditions in a whole-room calorimeter. METHODS: The following measurements were studied in 109 adults (49 male/45 female) at least 36 h after a bout of exercise: 1) aerobic fitness level assessed by VO2max, 2) body composition determined by underwater weighing, 3) resting metabolic rate (RMR) after an overnight fast, and 4) 24-h energy expenditure (EE) and substrate oxidation determined in a whole-room calorimeter. While in the calorimeter, subjects were provided with a diet (15% protein, 30% fat, and 55% carbohydrate) estimated to produce energy balance on a sedentary day and of similar nutritional composition to their daily dietary intake. RESULTS: We found strong negative correlations between VO2max and % body fat in both male and female subjects, but no relationship between VO2max and 24-h EE under the sedentary conditions of this study. In male subjects, VO2max (mL O2 x kg(-1) fat-free mass x min(-1)) was negatively related to fat oxidation (r = -0.397, P < 0.005), and fat oxidation was more closely related to fat mass (r = 0.434, P < 0.0002) than to fat-free mass (r = 0.165, NS). In contrast, none of these relationships were significant in females. CONCLUSION: The results show that in male subjects under sedentary conditions, 24-h fat oxidation is positively related to body fat mass and negatively related to VO2max (the marker used here for level of physical fitness). This supports our hypothesis that regularly active males maintain lower body fat stores as the low contribution to daily fat oxidation from a lower body fat mass is counterbalanced by the high contribution to fat oxidation from daily physical activity. The lack of a relationship between VO2max and 24-h EE under the sedentary conditions of this study suggests that the major effects of physical activity on total daily EE and fat oxidation may occur during and relatively quickly after an exercise bout. Further, these data also suggest that cessation of regular exercise will likely be associated with a high risk of positive fat balance and weight gain.  相似文献   
80.

Purpose

Pectus excavatum is frequently repaired using the minimally invasive placement of a substernal bar (Nuss procedure). Infectious complications after the Nuss procedure are potentially devastating. To date, the management of postoperative infectious complications has not been well described.

Methods

A retrospective review of all patients (N = 168) who underwent the Nuss procedure from January 1, 1997, to October 1, 2003, at our institution was performed. Six patients (4%) had postoperative infections, and their medical records were reviewed.

Results

Of the 6 patients, 5 underwent operative drainage for wound abscesses that developed 2 to 76 weeks postoperatively. The other patient developed cellulitis 12 months postoperatively and was treated effectively with antibiotics alone. Recurrent infections were treated in 3 of 6 patients, one of whom eventually required removal of the bar resulting in a mild, residual pectus excavatum defect. One of 6 patients has had the substernal bar removed electively. The remaining 4 continue to be without clinically apparent infection at this time and are over 1 year removed from their infection.

Conclusions

Although uncommon, infectious complications after the Nuss procedure require complex management strategies. Despite recurrent infection in some cases, most infectious complications occurring after the minimally invasive repair can be effectively treated without having to remove the substernal bar.  相似文献   
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