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31.
We evaluated the fractures of the lumbar and sacral vertebral limbus by disc impingement at the peripheral ring apophysis in 23 adults associated with trauma in 16 of them. Lumbalgia, radicular pain and narrow canal symptoms are the presenting forms of this underdiagnosed pathology. CT is the best method of examination, while plain roentgenograms and MR are usually negative. Accurate diagnosis and surgical technique with larger exposure are needed to resect the fractured fragments and protruded disc material for decompressing the roots and the dural sac. Our results were very good on the majority of cases. 相似文献
32.
Tennis leg: clinical US study of 141 patients and anatomic investigation of four cadavers with MR imaging and US 总被引:5,自引:0,他引:5
Delgado GJ Chung CB Lektrakul N Azocar P Botte MJ Coria D Bosch E Resnick D 《Radiology》2002,224(1):112-119
PURPOSE: To evaluate the ultrasonographic (US) findings in patients with a referring diagnosis of tennis leg and to explore the relative importance of the plantaris tendon and gastrocnemius muscle in the pathogenesis of this condition. MATERIALS AND METHODS: A cadaveric study was performed to outline the normal anatomy of the posterosuperficial compartment of the calf. Magnetic resonance (MR) imaging and US were performed, followed by gross anatomic correlation. US findings in 141 patients referred with a clinical diagnosis of tennis leg were retrospectively reviewed by means of consensus of two radiologists. Images were analyzed with respect to the integrity of the lower-leg musculotendinous units, presence of fluid collection, and deep venous thrombosis. RESULTS: MR imaging and US enabled distinction of the musculotendinous unit of the plantaris from the remaining muscles of the lower extremity in cadaveric specimens. US findings in the 141 patients included rupture of the medial head of the gastrocnemius muscle in 94 patients (66.7%), fluid collection between the aponeuroses of the medial gastrocnemius and soleus muscles without muscle rupture in 30 patients (21.3%), rupture of the plantaris tendon in two patients (1.4%), and partial rupture of the soleus muscle in one patient (0.7%). Deep venous thrombosis was seen in isolation in 14 patients (9.9%). CONCLUSION: In patients with clinical findings of tennis leg who undergo US, abnormalities of the medial gastrocnemius muscle appear to be more common than those of the plantaris tendon. 相似文献
33.
A prospective randomized study comparing D2 total gastrectomy versus D2 total gastrectomy plus splenectomy in 187 patients with gastric carcinoma 总被引:21,自引:0,他引:21
BACKGROUND: Classic surgical treatment of upper third gastric carcinoma is based on an extended total gastrectomy, including splenectomy. The purpose of this study was to perform a prospective randomized clinical trial comparing the early and late results of total gastrectomy (TG) versus total gastrectomy plus splenectomy (TGS). METHODS: One hundred eighty-seven patients with gastric carcinoma were included. In all patients a D2 total gastrectomy was performed. During surgery they were randomized to 1 of 2 operative options. They were monitored to their death or to 5 years later if they were alive. RESULTS: Operative mortality was similar after both operations (3% after TG and 4% after TGS). Septic complications after surgery were higher after TGS compared with TG (P <.04). Five-year survival rates were not statistically different between groups or in subset analysis according to stage of disease. CONCLUSIONS: On the basis of the results of the present prospective randomized trial, splenectomy is not necessary in early stages of disease. A low operative mortality rate (less than 3%) must be achieved to obtain good long-term results. 相似文献
34.
Mitochondrial DNA deletions/rearrangements in parkinson disease and related neurodegenerative disorders 总被引:7,自引:0,他引:7
Gu G Reyes PE Golden GT Woltjer RL Hulette C Montine TJ Zhang J 《Journal of neuropathology and experimental neurology》2002,61(7):634-639
Inhibition of mitochondrial respiratory chain function may contribute to dopaminergic neurodegeneration in the substantia nigra (SN) of patients with Parkinson disease (PD). Since large-scale structural changes (e.g. deletions and rearrangements in mitochondrial DNA [mtDNA]) have been associated with mitochondrial dysfunction, we tested the hypothesis that increased total mtDNA deletions/rearrangements are associated with neurodegeneration in PD. This study employed a well-established technique, long-extension polymerase chain reaction (LX-PCR), to detect the multiple mtDNA deletions/rearrangements in the SN of patients with PD, multiple system atrophy (MSA), dementia with Lewy bodies (DLB), Alzheimer disease (AD), and age-matched controls. We also compared the total mtDNA deletions/rearrangements in different brain regions of PD patients. The results demonstrated that both the number and variety of mtDNA deletions/rearrangements were selectively increased in the SN of PD patients compared to patients with other movement disorders as well as patients with AD and age-matched controls. In addition, increased mtDNA deletions/rearrangements were observed in other brain regions in PD patients, indicating that mitochondrial dysfunction is not just limited to the SN of PD patients. These data suggest that accumulation of total mtDNA deletions/rearrangements is a relatively specific characteristic of PD and may be one of the contributing factors leading to mitochondrial dysfunction and neurodegeneration in PD. 相似文献
35.
Braghetto I Csendes A Burdiles P Korn O Compan A Guerra JF 《World journal of surgery》2002,26(10):1228-1233
Benign esophageal stricture is a serious complication of persistent gastroesophageal reflux in patients with esophagitis and Barrett's esophagus. A classification of the severity of the stricture is proposed, based on its internal diameter, its length, and the ease or difficulty in dilating it. Among 185 patients with esophageal strictures secondary to reflux esophagitis, 77 (41.6%) corresponded to type I or mild stricture, 73 (39.4%) to type II or moderate, and 35 (19.6%) to type III. Medical treatment was performed in only 15 cases, with 73% recurrence. Three types of surgical procedures were employed, always after dilatation, improvement of nutritional status, and a complete preoperative work-up: (1) conservative antireflux surgery, which had a high incidence of recurrence (41.1%); (2) acid suppression and duodenal diversion, in which 68 patients had a mortality rate of 2.9% and a recurrence rate of 4.4% (p <0.002); and (3) esophageal resection, which in 7 patients resulted in 1 death and no late recurrence. It is concluded that classification of the severity of the stricture is important to indicate the most appropriate treatment. Conservative antireflux surgery is followed by a high recurrence rate at late follow-up, whereas acid suppression and duodenal diversion seem to be an adequate procedure that is followed by a very low recurrence rate. Esophageal resection is indicated only for patients with severe or critical esophageal strictures. 相似文献
36.
Della Valle AG Ruzo PS Pavone V Tolo E Mintz DN Salvati EA 《The Journal of arthroplasty》2002,17(7):870-875
We evaluated the reproducibility of the Brooker classification for heterotopic ossification (HO) and, based on the results and weaknesses observed, proposed a simplified system with addition of objective criteria. Six observers classified radiographs of 169 total hip arthroplasties, using the Brooker classification and a modified system consisting of i) absence of HO or islands measuring <1 cm in length, ii) islands >1 cm or spurs leaving at least 1 cm between femur and pelvis, and iii) spurs leaving <1 cm between opposing surfaces or bony ankylosis. Reproducibility was calculated using kappa statistics. For the Brooker classification, interobserver kappa averaged 0.43 (range, 0.74-0.18) (poor). Intraobserver kappa averaged 0.74 (fair). For the modified classification, interobserver kappa averaged 0.59 (range, 0.51-0.76) (fair). Intraobserver kappa averaged 0.78 (good). Interobserver differences were significant (P=.0085). Interobserver consistency to detect severe HO (Brooker 3 and 4, or grade C) improved from 52% to 76% with the modified system. The new classification showed adequate interobserver reproducibility, less variability, and improved consistency for classification of significant HO. 相似文献
37.
The present study describes a monoclonal antibody-based enzyme immunoassay (ELISA) for the quantitation of lipoprotein(a), Lp(a), in human plasma. Two antibodies to Lp(a), 2F4E7 and 8G12G7, were produced and characterized as specific and high affinity antibodies against Lp(a). A reference control serum was utilized to prepare the standard curve in a Lp(a) concentration range from 0.015 to 0.5 ug/ml. A biotinylated monoclonal antibody against apoB-LDL was used as the second antibody. The comparison of the standardized ELISA using mAb 2F4E7 with an ELISA using a characterized mAb against Lp(a) (clone KO9) as capture antibody showed that the Lp(a) concentration of two standard sera was similar with both assays. Furthermore, when compared with an electroimmunoassay kit, similar Lp(a) concentrations for the standard were also obtained. 相似文献
38.
PRIMARY PREVENTION: Preventive measures against esophageal varicose vein bleeding are needed for grade 2 risk resulting from the presence of large varix. Medical or endoscopic methods can be used. USEFUL DRUGS: With beta-blockers the incidence of a first bleeding episode is significantly reduced and mortality is almost significantly reduced. Three controlled trials have demonstrated that a nitrate derivative beta-blocker combination improves the efficacy of beta-blockers in terms of reduced bleeding. Nitrates can be prescribed alone in case of a contraindication for beta-blockers but the efficacy is poorly demonstrated. SCLEROTHERAPY: Both incidence of first bleeding episode and mortality are significantly reduced after sclerotherapy. Variable results have however been reported and sclerotherapy is probably only effective in high-risk patients; the consensus conference has not recommended its use. On the contrary, endoscopic ligature is probably useful since 5 preliminary studies have demonstrated a significant effect on first bleeding and mortality. Its relative contribution compared with propranolol remains to be demonstrated. RECOMMENDATIONS: The first intention therapy should rely on beta-blockers or nitrates in case of a contraindication or adverse effect. Endoscopic ligature can be discussed in high-risk patients. The beta-blocker-nitrate combination and the beta-blocker-endoscopic treatment combination cannot be recommended at the present time. SECONDARY PREVENTION: Meta-analyses have shown that beta-blockers or sclerotherapy significantly reduce the incidence of recurrent bleeding and mortality. Sclerotherapy significantly reduces the risk of recurrent bleeding compared with beta-blockers although there is no difference in mortality and the incidence of complications is significantly greater with sclerotherapy. Associating the two methods can significantly reduce recurrent bleeding but has no effect on mortality. Elastic ligature is significantly more effective in terms of recurrent bleeding and mortality or complication rate. Transjugular intrahepatic portosystemic shunt (TIPS) significantly reduces the incidence of recurrent bleeding but has no effect on mortality and the risk of hepatic encephalopathy is increased. PRACTICAL ATTITUDE: Elastic ligature can be proposed as a first intention treatment. Sclerotherapy is useful to eradicate varix after size reduction by ligature and to prevent recurrence. In case of failure, a TIPS or surgical shunt can be discussed. Liver transplantation would be indicated in high-risk patients keeping in mind that digestive tract bleeding is a supplementary argument favoring transplantation. RECOMMENDATIONS: The international consensus group (CFEHTP) recommends elastic ligature or beta-blockers, endoscopic treatment being preferred. TIPS or surgical shunt may be discussed in case of failure. 相似文献
39.
Donor hepatitis C seropositivity: clinical correlates and effect on early graft and patient survival in adult cadaveric kidney transplantation 总被引:4,自引:0,他引:4
Bucci JR Matsumoto CS Swanson SJ Agodoa LY Holtzmuller KC Peters TG Abbott KC 《Journal of the American Society of Nephrology : JASN》2002,13(12):2974-2982
The impact of hepatitis C virus-positive donor kidneys on patient survival has not been analyzed in a national study. This study analyzed 20,111 adult (age, > or =16 yr) recipients having solitary cadaveric kidney transplants from adult donors with valid donor hepatitis C serologies from July 1, 1994, to June 30, 1998, in an historical cohort study (the 2000 United States Kidney Data System) of patient survival. Analysis was by the Cox proportional hazards models, which corrected for characteristics thought to affect outcomes. Of 484 kidneys positive for hepatitis C virus serology, 165 (34%) were given to recipients with confirmed negative hepatitis C serologies. Unadjusted 3-yr patient survival was 93% in all recipients of donor hepatitis C-negative kidneys versus 85% in all recipients of donor hepatitis C-positive kidneys (P = 0.01). Among hepatitis C-positive recipients, those who received hepatitis C-positive kidneys had worse survival than recipients of hepatitis C-negative kidneys. Among elderly hepatitis C-negative recipients, those who received hepatitis C-positive kidneys also had worse survival; in fact, all recipients of donor hepatitis C-positive kidneys had increased risk of mortality (P = 0.028). There were no significant interactions between donor hepatitis C positivity and either recipient hepatitis C positivity or older recipient age. The use of hepatitis C-positive kidneys in recipients who were hepatitis C-negative was fairly common and contrary to some current recommendations. Recipients of donor hepatitis C-positive kidneys were at independently increased risk of mortality, with no evidence that any subgroups were less affected. 相似文献
40.
Csendes A Burdiles P Braghetto I Korn O Díaz JC Rojas J 《World journal of surgery》2002,26(5):566-576
The usual surgical treatment for patients with Barrett's esophagus (BE) is a classic Nissen fundoplication or posterior gastropexy with cardial calibration. However, some surgical reports as well as our experience suggest that the rate of failure of the Nissen fundoplication or Hill's posterior gastropexy in patients with BE is significantly higher than in those with reflux esophagitis without BE, probably due in part to the persistence of duodenal reflux into the esophagus. Our aim was to determine the late subjective and objective results of an operation consisting in "acid suppression" (vagotomy-partial gastrectomy) and "duodenal diversion" (Roux-en-Y anastomosis) as a primary surgical procedure for patients with BE. Altogether, 210 patients were subjected to this technique. It consisted in a primary operation in 142 patients and revision surgery in 68. They underwent complete clinical, radiologic, endoscopic, histologic, and manometric studies. In some cases 24-hour pH studies, Bilitec studies, gastric emptying, and gastric acid secretion evaluations were performed. There were two deaths (0.95%), and postoperative morbidity was low (5.3%). The late mean follow-up (58 months) for 146 patients who completed a follow-up longer than 24 months showed Visick I and II grades in 91.1% of the cases. In 14.9% of the cases 24-hour pH monitoring showed excessive acid reflux 1 year after surgery. No dysplasia or adenocarcinoma has appeared up to now. Functional studies showed significant alleviation of lower esophageal sphincter (LES) incompetence, with abolition of duodenal reflux into the esophagus. Gastric emptying of solids was normal, and basal and peak gastric acid output remained at a low level 8 to 10 years after surgery. In patients with BE, with severe damage of the LES and esophageal peristalsis, the "suppression diversion" operation completely abolishes the reflux of injurious components of the refluxate and improves sphincter competence. This effect is permanent and avoids the appearance of dysplasia or adenocarcinoma. 相似文献