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61.
STUDY DESIGN: The study of two patients whose rib deformity was treated using a new endoscopic thoracoplasty technique is reported. OBJECTIVES: To report a new endoscopic thoracoplasty technique for the treatment of rib deformities associated with idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: Thoracoplasty has traditionally been performed as an open procedure, often necessitating additional incisions and/or tissue dissection. METHODS: Two children with significant rib humps associated with idiopathic scoliosis were treated with a new endoscopic thoracoplasty technique. RESULTS: Both children showed dramatic cosmetic improvement of their rib deformity. CONCLUSIONS: The indications for the use of video-assisted thoracoscopic surgery in the treatment of pediatric spinal deformity are expanding. We have extended our video-assisted thoracoscopic surgery repertoire to include endoscopic thoracoplasty for treatment of rib deformities associated with idiopathic scoliosis. The technique for endoscopic thoracoplasty is discussed, and illustrative cases are presented. 相似文献
62.
Autosomal dominant polycystic kidney disease (ADPKD) is a systemic disorder with a variety of cardiovascular manifestations. This study presents a group of patients with ADPKD who had intracranial arterial dolichoectasia. One hundred seventy-eight ADPKD patients were screened with magnetic resonance angiography, 40 ADPKD patients had conventional angiography, and 98 ADPKD patients underwent a brain autopsy. For comparison, 360 patients without ADPKD who had magnetic resonance angiography and conventional angiography or brain autopsy were also studied. The prevalence of asymptomatic intracranial arterial dolichoectasia was 2.2% (4 of 178), 2.5% (1 of 40), and 2.0% (2 of 98) in the three ADPKD groups, respectively. None of the patients without ADPKD had intracranial arterial dolichoectasia. In addition to the seven patients with asymptomatic disease, two ADPKD patients with vertebrobasilar dolichoectasia had posterior circulation ischemic symptoms. The mean age of the nine patients (five men and four women) was 56.6 yr (range, 41 to 67 yr). The posterior circulation was involved in five patients, the anterior circulation was involved in two patients, and both were involved in two patients. Arterial dissection was believed to have caused middle cerebral artery dolichoectasia in one patient, and intracranial arterial dissections were strongly suspected in two other patients. Six of the nine patients with intracranial arterial dolichoectasia had additional vascular manifestations of ADPKD. Some patients with ADPKD are at an increased risk of developing intracranial arterial dolichoectasia and dissections. Recognizing this association is important because (1) it may be a cause of stroke; (2) it may mimic a saccular aneurysm on radiographic studies; and (3) it suggests that the arteriopathy of ADPKD may be more generalized than previously believed. 相似文献
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64.
The changing face of emphysematous cholecystitis 总被引:1,自引:0,他引:1
Emphysematous cholecystitis is a variant of acute cholecystitis characterized by the presence of gas in the gall bladder lumen, wall or pericholecystic tissues in the absence of an abnormal communication between the biliary system and the gastrointestinal tract. In the past, the diagnosis has relied on the plain abdominal radiograph (AXR), since there are no clinical features to separate this condition from simple acute cholecystitis. The apparently high mortality and morbidity associated with emphysematous cholecystitis has previously emphasized the importance of emergency cholecystectomy. We have reviewed eight cases of emphysematous cholecystitis presenting to this hospital over the last 5 years. The diagnosis was made on AXR in only one of these cases. Ultrasound (US) scans were performed in all eight cases, of which five were positive and three negative, due to non-visualization of the gall bladder. In the three negative cases, the diagnosis was made on subsequent CT scans. On initial clinical examination, only one of the eight patients appeared systemically unwell and conservative management was employed in five of the patients. The remaining three patients underwent cholecystectomy within 3-5 days because of continuing signs or symptoms. It is concluded that the AXR is relatively insensitive in the diagnosis of emphysematous cholecystitis. As a result of the regular use of US in suspected hepatobiliary disease, emphysematous cholecystitis is being diagnosed with increased frequency, uncovering a broad spectrum of disease ranging from mild to severe. Previously, failure to separate milder cases from simple acute cholecystitis may have been responsible for reports of unremitting severity and progression requiring emergency cholecystectomy. Based on clinical assessment, conservative surgical management is possible in a significant proportion of patients. 相似文献
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66.
Small-cell carcinoma (also known as oat-cell carcinoma) is a rare tumor that previously concerns the lung; small-cell carcinoma of the bladder is extremely rare (0.5% of all bladder malignancies). The Authors report here the case of a 78th years old man. Fourteen months before our observation he was submitted to a partial cystectomy for a small-cell carcinoma of the bladder cupola. There was no evidence of extra-vesical location at that moment and the patient was not submitted to any adjuvant therapy. At the moment of our observation the disease was very advanced and the patient died in a few time. The Authors discuss about the therapy of bladder small-cell carcinoma in the few cases described by the literature and about the survival of those patients. A radical surgical treatment in association with an adjuvant chemo- or radiotherapy appears as a better way to treat these patients. On account of this case the Authors agree with this choice and conclude that only a combined treatment can allow a better survival. 相似文献
67.
The unquestionable advantages of multiple-input multiple-output (MIMO) systems are having a strong influence on the development of new wireless systems, both in wireless local-area networks (WLANs), and in those designed to offer broadband fixed wireless access (BFWA) services in wireless metropolitan-area networks (WMANs). The MIMO channel characterization in different environments and for different operating frequency bands is a crucial factor in the design of new systems and standards, and for adequate planning of existing systems. This article makes two main contributions. First, the experimental characterization of a 2 times 2 MIMO channel at a frequency of 2.4 GHz in a canonical outdoor-indoor scenario is presented. The channel characterization performed includes the analysis of the spatial correlation between the MIMO system subchannels and its impact on the channel capacity. Second, on the basis of the capacity results obtained, a proposal is made for the use of a 2 times 2 MIMO system in outdoor-indoor scenarios for BFWA applications in metropolitan environments. The proposal is based on the experimentally verified hypothesis that the path loss due to building penetration can be practically compensated for by the diversity gain of 2 times 2 systems 相似文献
68.
MP Amador Rodríguez A Artal Cortés E Rebollar Torres A Idoipe Tomás P Palomo Palomo J Martínez Trufero 《Canadian Metallurgical Quarterly》1998,13(4):198-204
A B16 melanoma-specific CD8+ T cell line (AB1) was established from the spleen cells of C57BL/6 mice cured of B16 melanoma with interleukin (IL)-12 treatment. The AB1 line exclusively used T cell receptor Vbeta11. The AB1 cells exhibited a cytolytic activity against both syngeneic B16 melanoma and allogeneic P815 mastocytoma, whereas a cold inhibition assay revealed specificity of the AB1 cells against B16 melanoma. Their lostability to kill a class I loss variant of B16 melanoma was restored by the transfection of H-2Kb gene. In addition, their interferon (IFN)-gamma production was significantly suppressed by the addition of anti-H-2Kb monoclonal antibody, and RT-PCR analysis showed that the AB1 line expressed the mRNA encoding IFN-gamma, but not IL-4 or IL-10. The experiment using synthetic peptides of tyrosinase-related protein-2 (TRP-2) revealed that the AB1 cells could recognize TRP-2(181-188) peptide. Moreover, the AB1 cells showed an in vivo antitumor effect against established pulmonary metastases of B16 melanoma. Overall, these results indicate that the Tc1-type Vbeta11+ AB1 cells exert an antitumor activity against syngeneic B16 melanoma through recognition of TRP-2(181-188) peptide in an H-2Kb-restricted manner. 相似文献
69.
70.
GW Daneker SA Lund SW Caughman RA Swerlick AH Fischer CA Staley EW Ades 《Canadian Metallurgical Quarterly》1998,34(5):370-377
BACKGROUND: Epidemiologic data concerning skin diseases in many rural areas in sub-Saharan Africa are not available. Little is known about the effect of regular treatment schedules by paramedical staff (especially community health workers) in the primary healthcare system on the severity and prevalence of dermatoses. METHODS: 5780 school and pre-school children from 13 primary schools in four sublocations in rural western Kenya (Kisumu District) were examined for dermatoses by the author, together with community health workers in 1993. On-the-spot training and weekend seminars about important and common dermatoses were also given. In 1994 a dermatology program was started within the primary healthcare system. Twelve trained community health workers carried out regular school visits once a week and diagnosed and treated pupils with dermatoses. Treatment was performed with gentian violet 1% solution for bacterial skin infections, Whitfield's ointment for dermatophytoses, benzylbenzoate emulsion 25% for scabies, and hydrocortisone acetate 1% cream for eczemas. All schools were visited again in 1995 to evaluate the long-term effects of the program. RESULTS: In 1993, the prevalence rate for dermatoses was 32.4%. Most of the skin diseases found were of infective origin (27.1% were caused by bacteria, 21.6% by fungi, and 17.6% by arthropods, mainly scabies mites). Dermatitis accounted for 3.5%. In 1995, the prevalence of dermatoses declined to 29.6% (p<0.05), and this reduction was most strongly observed for tropical ulcers and tinea capitis. Additionally, there was an improvement in the extent and severity of skin diseases. CONCLUSIONS: This study defines, for the first time, the number and extent of skin diseases in children in rural Kisumu District; most dermatoses were of infective origin. The study demonstrates that community health workers in the primary healthcare system are capable of dealing successfully with the most common dermatoses in children following a short training period. 相似文献