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141.
Sclerosing bone dysplasias are a poorly understood group of developmental anomalies, much of whose etiology is still obscure. The list of conditions constituting this group is relatively short: osteopetrosis (Albers-Schönberg disease), pycnodysostosis (Maroteaux-Lamy disease), enostosis (bone island), osteopoikilosis, osteopathia striata (Voorhoeve disease), progressive diaphyseal dysplasia (Camurati-Engelmann disease), hereditary multiple diaphyseal sclerosis (Ribbing disease), four types of endosteal hyperostosis (van Buchem disease, Worth disease, Nakamura disease, and Truswell-Hansen disease), dysosteosclerosis, metaphyseal dysplasia (Pyle's disease), craniometaphyseal dysplasia, melorheostosis (Leri disease), and craniodiaphyseal dysplasia. There are instances in which two or more of the above disorders coexist. These are termed overlap syndromes, most commonly involving osteopathia striata, osteopoikilosis, and melorheostosis. A classification of these dysplasias is elaborated based on a target-site approach that views them as disturbances in development associated with the processes of either endochondral or intramembranous bone formation, or both. Accumulated evidence suggests that many of these disorders stem from common defects in bone resorption and/or formation during the processes of skeletal maturation and modeling. Finally, the subgroup of overlap syndromes is emphasized as indicating a strong interrelationship between the sclerosing dysplasias of bone, with perhaps a common pathogenesis for many.This article is one in a series of review articles which represent expansions of papers presented at the annual meeting of the International Skeletal Society and were solicited by the editors  相似文献   
142.
In an attempt to differentiate among joint effusion, synovitis, pannus, and subchondral sclerosis in patients with clinically proved chronic rheumatoid arthritis, we used gadopentetate dimeglumine-enhanced MR imaging to examine 23 patients with acute knee symptoms. All patients had had rheumatoid arthritis for more than 6 months and satisfied four or more of the criteria of the American Rheumatism Association for rheumatoid arthritis. MR imaging was performed on a 1.5-T machine by using unenhanced T1-weighted spin-echo imaging, unenhanced T2*-weighted gradient-echo imaging, and unenhanced and enhanced T1-weighted gradient-echo imaging. Signal intensities of the synovium and bone marrow were measured with the region-of-interest technique on unenhanced and enhanced T1-weighted gradient-echo scans. Conventional radiographs were available for each patient. Joint effusion, synovitis, intraarticular pannus, subchondral sclerosis, and subchondral pannus had the same signal intensities on unenhanced T1-weighted spin-echo, unenhanced T1-weighted gradient-echo, and unenhanced T2*-weighted gradient-echo MR images, and could not be differentiated from one another. On enhanced T1-weighted gradient-echo sequences, pannus and synovitis showed marked enhancement in 15 patients, whereas joint effusion and sclerosis did not. Synovitis was diagnosed if the synovial membrane showed high enhancement; pannus was diagnosed if enhancing masses were seen within the joint space or in the subchondral area. In eight of the 23 joints, there was no enhancement of the synovium or intraarticular or subchondral tissue. We conclude that gadopentetate dimeglumine-enhanced MR imaging allows differentiation between synovitis and joint effusion and between subchondral pannus and subchondral sclerosis. Enhancement of the synovium and pannus indicates acute inflammation of the joint.  相似文献   
143.
Gadolinium-DTPA (diethylenetriaminepentaacetic acid)-cascade-polymer, a potential new blood pool contrast agent for magnetic resonance (MR) imaging, was compared with a known blood pool agent, Gd-DTPA-polylysine, in an animal model. The relative signal intensities of liver, renal cortex, pancreas, and trunk muscle were assessed in 12 pigs between 4 seconds and 120 minutes after injection of a 20 μmol/kg dose of each contrast agent, by using a FLASH (fast low-angle shot) sequence. Except for muscle, all tissues showed visible enhancement after injection of either contrast agent. After injection of Gd-DTPA-polymer, enhancement patterns in the liver, renal cortex, and pancreas were similar to those seen after injection of Gd-DTPA-polylysine. No statistically significant differences in enhancement between the two contrast agents were found at any time point. The authors conclude that the contrast kinetics of Gd-DTPA-cascade-polymer are similar to those of Gd-DTPA-polylysine and that this agent may also be used as a blood pool contrast agent for MR imaging.  相似文献   
144.
OBJECTIVE: Previous work has suggested that hyperamylasemia in patients who undergo operation for ruptured abdominal aortic aneurysm (AAA) is associated with poor outcome. The aims of this study were to determine, for the first time, the source of serum amylase in such patients and to examine the prognostic significance of amylase isoenzyme expression. METHODS: This study was designed as a prospective clinical and laboratory study. The study consisted of 40 patients who underwent operation for ruptured AAA and 10 patients who underwent operation for non-ruptured AAA. The main outcome measures were serum total and pancreatic and salivary amylase activities determined with enzymatic colorimetric assay before operation and 6 hours after aortic clamp release. RESULTS: Five of 40 patients (12.5%) with rupture and one of 10 patients (10%) with non-rupture had elevated total amylase levels before operation, and seven of 31 patients (23%) with rupture and five of 10 patients (50%) with non-rupture had elevated total amylase levels after operation. The preoperative salivary amylase (P =.05) and postoperative pancreatic amylase (P <.02) levels were significantly lower in ruptured AAA as compared with non-ruptured AAA. The preoperative salivary amylase level was significantly lower in non-survivors of rupture, such that a level equal to or less than 45 U/L was associated with death in 11 of 13 patients (85%). CONCLUSION: These data do not support previous works that suggest that hyperamylasemia is associated with poor outcome in ruptured AAA. By contrast, a low preoperative salivary amylase level was associated with increased mortality in ruptured AAA and may be a marker of the severity of shock.  相似文献   
145.
146.
Purpose: To assess the shortest time for catheter removal with regard to the transhepatic or transperitoneal approach in patients undergoing percutaneous cholecystostomy (PC). Methods: In this prospective study, 40 consecutive high-risk patients with acute cholecystitis (calculous, n= 22; acalculous, n= 18) underwent PC by means of a transhepatic (n= 20) or transperitoneal (n= 20) access route. In 28 patients (70%) computed tomography was used for puncture guidance, while in the remaining 12 (30%) the procedures were performed under ultrasound control. A fistulography was performed on the 14th postprocedural day in all patients and was repeated weekly if the tract was found to be immature. The catheter was removed only if a mature tract without evidence of leakage was delineated. Results: In 36 of 40 patients the procedure was technically successful (90%). Three of the unsuccessful punctures were attempted transperitoneally and one transhepatically. Thirty-five of 36 patients showed rapid improvement within the first 48 hr following the procedure (96%). Three of them died of their severe underlying disease (7.5%) and in another three the catheter was accidentally removed prior to the first fistulography (7.5%). A total of 30 patients could be fully evaluated after the procedure: 15 with a transhepatic, and 15 with a transperitoneal PC. Whereas 14 of 15 patients (93%) with transhepatic gallbladder access developed a mature tract after 14 days and the remaining patient after 3 weeks, only 2 of 15 patients (13%) with a transperitoneal route presented a mature tract after 2 weeks (p < 0.0001; χ2 test with Yates' correction). Eleven patients (73%) with transperitoneal access required 3 weeks and two patients (13%) 4 weeks for complete tract formation. Conclusion: A period of 2 weeks suffices for the majority of patients to develop a mature tract when the transhepatic access route is used; when using the trans- peritoneal route at least 3 weeks are required. We suggest that the transhepatic route is preferable since it allows earlier removal of the catheter and reduces the incidence of complications and discomfort for the patients. Received: 0/00/00/Accepted: 0/00/00  相似文献   
147.

Background

In April 2010 Sierra Leone launched a nationwide program that provides free health care to all pregnant and lactating women and children under 5 years old. This study evaluates the effect that the free health-care program had on pediatric surgical activities of Connaught Hospital.

Methods

The study period was defined as the 20 months before and after April 27, 2010, the start date of the free health-care program. Data on age, gender, diagnosis, and procedure for patients under 5 years of age and the total number of operations were collected from the Connaught Hospital operating room logbook.

Results

The number of operations on children under 5 increased by 500 %, from 42 to 210 cases. This increase was significantly larger than the 17 % increase of 1,393–1,630 seen with operations for patients 5 years and older (p < 0·01).

Conclusion

The decision by the Sierra Leone President to institute a program of free health care for children under 5 has resulted in an increased number of pediatric surgical cases at Connaught Hospital. Efforts should be undertaken to provide additional supplies and equipment and to develop training programs for surgeons and support staff to care for the children in need of surgical care.  相似文献   
148.
The purpose of this study was to determine the actual standardized uptake value (SUV) by using the lesion size from computer tomography (CT) scan to correct for resolution and partial volume effects in positron emission tomography (PET) imaging. This retrospective study included 47 patients with lung lesions seen on CT scan whose diagnoses were confirmed by biopsy or by follow up CT scan when the PET result was considered negative for malignancy. Each lesion's FDG uptake was quantified by the SUV using two methods: by measuring the maximum voxel SUV (maxSUV) and by using the lesion's size on CT to calculate the actual SUV (corSUV). Among small lesions (2.0 cm or smaller on CT scan), ten were benign and 17 were malignant. The average maxSUV was 1.43+/-0.77 and 3.02+/-1.74 for benign and malignant lesions respectively. When using an SUV of 2.0 as the cutoff to differentiate benignity and malignancy, the sensitivity, specificity, and accuracy were 65%, 70%, and 67% respectively. When an SUV of 2.5 was used for cutoff, the sensitivity, specificity, and accuracy were 47%, 80%, and 59% respectively. The average corSUV was 1.65+/-1.09 and 5.28+/-2.71 for benign and malignant lesions respectively. Whether an SUV of either 2.0 or 2.5 was used for cutoff, the sensitivity, specificity, and accuracy remained 94%, 70%, and 85% respectively. The only malignant lesion that was falsely considered benign with both methods was a bronchioalveolar carcinoma which did not reveal any elevated uptake of fluorine-18 fluorodeoxyglucose (FDG). Of the large lesions (more than 2.0 cm and less than 6.0 cm), one was benign and 19 were malignant and the corSUV technique did not significantly change the accuracy. It is concluded that measuring the SUV by using the CT size to correct for resolution and partial volume effects offers potential value in differentiating malignant from benign lesions in this population. This approach appears to improve the accuracy of FDG-PET for optimal characterization of small lung nodules.  相似文献   
149.
Our objective was to compare the effectiveness of percutaneous cholecystostomy (PC) vs conservative treatment (CO) in high-risk patients with acute cholecystitis. The study was randomized and comprised 123 high-risk patients with acute cholecystitis. All patients fulfilled the ultrasonographic criteria of acute inflammation and had an APACHE II score > or =12. Percutaneous cholecystostomy guided by US or CT was successful in 60 of 63 patients (95.2%) who comprised the PC group. Sixty patients were conservatively treated (CO group). One patient died after unsuccessful PC (1.6%). Resolution of symptoms occurred in 54 of 63 patients (86%). Eleven patients (17.5%) died either of ongoing sepsis (n=6) or severe underlying disease (n=5) within 30 days. Seven patients (11%) were operated on because of persisting symptoms (n=3), catheter dislodgment (n=3), or unsuccessful PC (n=1). Cholecystolithotripsy was performed in 5 patients (8%). Elective surgery was performed in 9 cases (14%). No further treatment was needed in 32 patients (51%). In the CO group, 52 patients (87%) fully recovered and 8 patients (13%) died of ongoing sepsis within 30 days. All successfully treated patients showed clinical improvement during the first 3 days of treatment. Percutaneous cholecystostomy in high-risk patients with acute cholecystitis did not decrease mortality in relation to conservative treatment. Percutaneous cholecystostomy might be suggested to patients not presenting clinical improvement following 3 days of conservative treatment, to critically ill intensive care unit patients, or to candidates for percutaneous cholecystolithotripsy.  相似文献   
150.
Deep brain stimulation (DBS) is effective for Parkinson’s disease (PD), dystonia, and essential tremor (ET). While motor benefits are well documented, cognitive and psychiatric side effects from the subthalamic nucleus (STN) and globus pallidus interna (GPi) DBS for PD are increasingly recognized. Underlying disease, medications, microlesions, and post-surgical stimulation likely all contribute to non-motor symptoms (NMS).  相似文献   
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