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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
981.
982.
983.
Higueras Guerrero V Torregrosa Andrés A Martí-Bonmatí L Casillas C Sanfeliu M 《European radiology》1999,9(9):1796-1799
The aim of this study was to assess the accuracy of MR in the diagnosis of synovialisation of the anterior cruciate ligament
(ACL) compared with arthroscopy. One hundred and forty-nine patients were examined with MR imaging and arthroscopy of the
knee. The MR sign used to consider a synovialised ACL consisted of hypointense fibrillar tracts, disrupted and wavily, in
its expected course. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV), comparison
of proportions (McNemar test) and Kappa values for agreement between MR imaging and arthroscopy were calculated. Of the 133
(89.3 %) ligaments without synovialisation at arthroscopy, 130 accorded with the MR results. Of the 16 (10.7 %) synovialised
ligaments, 13 accorded with the MR results. Three false-positive and three false-negative MR diagnoses were identified. The
agreement between both techniques was excellent (Kappa = 0.79; p = 0.000), without differences (McNemar test; p = 1). Sensitivity was 0.81, specificity 0.98, PPV 0.98 and NPV 0.81. Magnetic resonance imaging is highly reliability for
synovialisation diagnosis. The imaging sign used to diagnose synovialised ACL (hypointense comma-like tracts in its expected
course) is reliable. As this reparative process can simulate an intact ligament, knowledge of this sign is important in diagnosing
synovialisation of ACL tears so as not to confuse it with normal ACL.
Received: 17 June 1998; Accepted: 6 August 1998 相似文献
984.
985.
Our present knowledge of the structure and function of glycoproteins in bone tissue is very limited. The introduction of lectins into histology offered principally a new approach for studying the presence and chemical structure of glycoproteins in tissue sections. In this paper these highly specific carbohydrate binding molecules have been used to characterize glycoproteins in the cellular elements of normal bone and benign bone lesions. We retrospectively examined 35 benign bone lesions (7 fibrous dysplasias, 5 foreign body granulomas, 5 epulis, 8 osteoid osteomas, 10 giant cell tumors) together with 25 normal bone samples. In normal bone samples and all cases of benign bone lesions, two characteristic types of PNA binding were found after neuraminidase digestion in osteoclasts. In osteoclasts which did not adhere to bone surface, diffuse intracytoplasmic PNA binding was seen, and following the adherence to the bone surface, it disappeared, and the resorption zone became stainable. We assume that this PNA binding glycoprotein is formed in the cytoplasm of osteoclasts, then, after the activation of osteoclasts, the glycoprotein gets accumulated at the resorption zone of the cytomembrane where it plays a significant role in the bone resorption. 相似文献
986.
Bardet-Biedl syndrome is an autosomal recessive disorder. It is characterized by cardinal anomalies including retinal dystrophy, digital malformations, mental retardation, obesity, and hypogonadism. Recently, renal anomalies also are mentioned among the cardinal signs. Although association of genital anomalies among affected boys are well known, the association of vaginal atresia and other structural genital anomalies are not mentioned among the less-common manifestations of Bardet-Biedl syndrome in girls. Two girls with Bardet-Biedl syndrome presented with hematometrocolpos in the preadolescent period and vaginal atresia was diagnosed. After surgical treatment and extended hospitalization, uncontrolled sepsis resulted in progressive renal failure and death of both patients. Vaginal atresia is often delayed or missed in the early childhood period. In girls with Bardet-Biedl syndrome, vaginal atresia or other structural genital anomalies should be evaluated more systematically during the initial diagnosis of the syndrome. In infancy, the evaluation of a child with vaginal atresia also should include the differential diagnosis of Bardet-Biedl syndrome. Vaginal atresia may either form a component of the syndrome, or girls who present with vaginal atresia in addition to other components of Bardet-Biedl syndrome might form a distinct entity. 相似文献
987.
The preventive effect of heparin on stricture formation after caustic esophageal burns 总被引:9,自引:0,他引:9
Bingöl-Kologlu M Tanyel FC Müftüoğlu S Renda N Cakar N Büyükpamukçu N Hiçsönmez A 《Journal of pediatric surgery》1999,34(2):291-294
BACKGROUND/PURPOSE: Preventing thrombus formation after caustic esophageal ingestion has been proposed to have beneficial effects. Therefore, an experimental study was carried out to investigate the effects of heparin on the esophagus after caustic burns. METHODS: Caustic esophageal burns were produced in rats by irrigation with 50% NaOH as described by Liu. Rats were divided into four groups as follows: group A, animals with esophageal burns, received placebo and underwent autopsy 48 hours after caustic injury; group B, animals with esophageal burns, received subcutaneous heparin treatment and underwent autopsy 48 hours after caustic injury; group C, animals with esophageal burns, received placebo and underwent autopsy 28 days after caustic injury; group D, animals with esophageal burns, received subcutaneous heparin treatment for 7 days and underwent autopsy 28 days after caustic injury. Histopathologic evaluation was performed in all groups, and collagen content of esophageal sections was analyzed by determination of hydroxyproline levels. RESULTS: Submucosal vascular thrombosis was encountered in all group A animals but the submucosal venules and arterioles were patent in most of group B animals. Esophageal strictures did not develop in any of group D animals, although varying degree of esophageal stenoses were encountered in all animals of group C. The circumferences of the burned segment have been narrowed to 3+/-1 mm in group C rats. There was obvious collagen deposition in submucosa, and epithelial regeneration was not complete in group C rats. Submucosa and epithelial integrity seemed normal in group D animals. Hydroxyproline contents in group D were significantly lower compared with group C (P < .05). CONCLUSIONS: Heparin has ameliorating effects on stricture formation after caustic esophageal burn. Those effects may occur through possible anticoagulant, antithrombotic, and endothelial protective effects, and modifying effects of heparin on wound healing. 相似文献
988.
989.
990.
Laparoscopic adrenalectomy 总被引:1,自引:0,他引:1
Pujol J Viladrich M Rafecas A Lladó L García-Barrasa A Figueras J Jaurrieta E 《Surgical endoscopy》1999,13(5):488-492
BACKGROUND: Laparoscopic adrenalectomy is a good option for removal of the adrenal gland that is becoming preferred over the conventional open technique. METHODS: We reviewed the initial 30 laparoscopic adrenalectomies (in 27 patients) that were performed at our institution from 1995 to 1998. We used the lateral decubitus transperitoneal approach in 26 cases and the retroperitoneal approach in only one case. The indications for adrenalectomy were Conn's adenoma in eight patients, pheochromocytoma in six, Cushing's syndrome in five, nonfunctional adenomas in seven, and metastasis in one case. RESULTS: Only two patients (7%) were converted to laparotomy. Operating time ranged from 75 to 240 min. Average adrenal gland size was 6.1 cm (range, 4-9 cm). There was no mortality, and morbidity occurred in only two patients (8%)-one case of self-limited gastrointestinal bleeding and one case of hypercapnia and subcutaneous emphysema (in the only patient operated by the retroperitonal approach). Mean hospital stay was 3 days (range, 1-6). CONCLUSIONS: Laparoscopic adrenalectomy is a safe and useful procedure for nearly all adrenal pathologies. Lateral decubitus transperitoneal approach is the procedure of choice in most cases. 相似文献