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991.
Yoon ST 《The Orthopedic clinics of North America》2004,35(1):95-100
Research in biologic methods of treating disc degeneration is still in its infancy. Many different strategies are being evaluated, but the gene therapy strategy stands out because of its potential for long-term efficacy. Choosing the correct gene for use in gene therapy is critically important. Of the many different classes of potentially therapeutic genes, the regulatory genes hold the most promise. Of the different gene therapy delivery methods, the most work has been performed with viral vectors, either ex vivo or in vivo. Current research now is turning toward in vivo experiments in rabbits. Efficacy and safety will be demonstrated first with smaller animal models. Beyond that, nonhuman primate experiments demonstrating efficacy and safety will be the penultimate step before initiation of human studies. 相似文献
992.
Yoon HE Nonaka K Fukuhara K Ueshima H Sugiura T Kaneda H Shimamoto S Imakita M Iwase K 《Kyobu geka. The Japanese journal of thoracic surgery》2004,57(11):1011-1015
We analyzed 7 patients with malignant pleural mesothelioma who underwent extrapleural pneumonectomy. Six men and a woman had a mean age of 65 years old. The postoperative mortality rate was 14% (1 death) and morbidity, 43% (3 cases). According to staging of International Mesothelioma Interest Group, 2 patients had stage I disease, 1 did stage II, 3 did stage III and 1 did stage IV. Local recurrences were found in 3 patients and metastasis in 2. In patients with local recurrences, 2 had irradiation with chemotherapy and 1, irradiation. In patients with recurrences of metastasis, 1 had chemotherapy and 1, supportive care. Seven patients with extrapleural pneumonectomy and 10 without surgery had median survivals of 16 months and 10 months, 1-year survival rates of 71% and 40% and 2-year survival rates of 57% and 0% respectively (p=0.071). Extrapleural pneumonectomy with adjuvant therapy could be effective treatment for malignant pleural mesothelioma. 相似文献
993.
Edwards CC Karpitskaya Y Cha C Heller JG Lauryssen C Yoon ST Riew KD 《The Journal of bone and joint surgery. American volume》2004,(2):251-256
BACKGROUND: Retrospective clinical studies frequently utilize surgeon records as a source of outcomes data. The accuracy of data derived from surgeon records, however, is unknown. The purpose of the present study was to evaluate the accuracy of surgeon records in documenting the prevalence of subjective adverse outcomes. METHODS: Consecutive patients who had undergone anterior cervical arthrodesis by four spine surgeons during a ten-month period were included. Surgeon records from the routine six-week, three-month, and six-month postoperative visits were examined for documentation of persistent dysphagia and dysphonia. Patients completed surveys inquiring about the presence and magnitude of symptoms at these three time-points. Agreement between the surgeon records and the patient surveys was analyzed with use of the kappa coefficient. RESULTS: One hundred and sixty-six patients had 342 postoperative visits. Dysphagia was documented twenty-six times in the surgeon records, compared with 107 times on the patient surveys. Dysphagia was thus underreported in 80% of cases. Similarly, dysphonia was documented ten times in the surgeon records, compared with seventy-two times on the patient surveys. Poor correlation between the surgeon records and the patient surveys was observed regardless of symptom severity, previous anterior cervical surgery, anterior arthrodesis of three motion segments or more, arthrodesis cephalad to the fifth cervical level, and anterior cervical plate use. Poor correlation between the surgeon records and the patient surveys also was observed for each surgeon, regardless of subspecialty or institution. CONCLUSIONS: Correlation between the surgeon records and the patient surveys was consistently poor, regardless of the specific patient and surgeon factor analyzed. While we chose to study dysphonia and dysphagia, it is conceivable that the results may be generalizable to many situations in which office notes are utilized to ascertain the prevalence of subjective adverse outcomes. These results suggest that the prevalence of such outcomes may be seriously underreported in studies that rely on the retrospective analysis of surgeon records. 相似文献
994.
Yang KH Yoon CS Park HW Won JH Park SJ 《Archives of orthopaedic and trauma surgery》2004,124(3):169-172
Introduction Adduction of the ipsilateral hip joint is necessary to facilitate closed hip nailing for trochanteric fracture. Even though positioning the patient supine with the perineal post against the ipsilateral medial thigh can change the course of the neurovascular structure in the proximal thigh, there have been no reports regarding the position of the femoral artery in the hip nailing position.Materials and methods We studied the position of the superficial femoral artery in 59 thighs using color-flow duplex scanning method in three hip nailing positions.Results The mean of the distance between the superficial femoral artery and the femur in 48 normal limbs was 20.28 mm in neutral position (D1), 11.85 mm in 20o adduction (D2), and 9.53 mm in 20o adduction plus 20o internal rotation of the foot plate (D3). The distances D2 and D3 were always shorter than D1 (p<0.001). D3 was less than 10 mm in 30 of the normal limbs (62.5%) and less than 5 mm in 4 (8%). In 11 patients who sustained a trochanteric fracture, the mean of D1, D2, and D3 in the injured limbs was 25.28 mm, 17.98 mm, and 14.38 mm, respectively. The mid-thigh circumference and D3 of the injured limbs were always greater than those of the normal limbs (p<0.001). However, D3 of both sides was less than 10 mm in 3 patients.Conclusion To lessen the vascular injury during hip nailing, we recommend that the limb be placed in neutral position during preparation of the interlocking holes. 相似文献
995.
996.
Solitary fibrous tumor arising in gastric serosa 总被引:1,自引:0,他引:1
The solitary fibrous tumor (SFT) of peritoneum, especially arising in gastric serosa, is extremely rare. A case of SFT arising in gastric serosa of a 70-year-old man is reported. On abdominal computed tomography scan, an approximate 8.0 × 5.3 cm-sized solid mass with multiple nodular calcifications was noted in the omentomesentery of right upper abdomen, which was abutting to the gastric antral wall. At laparotomy the tumor was tightly attached to the gastric serosa and was completely excised by wedge resection of the stomach. The cut surfaces of the tumor were pale brown to pale yellow, firm, with multifocal yellowish, gritty, stony-hard nodules and cystic changes. Microscopically, the tumor was composed of mildly cellular benign-appearing spindle-shaped cells and bands of hyalinized collagen in varying proportions. The tumor revealed predominantly sclerosing pattern with extensive hyalinized fibrosis and multifocal dystrophic calcifications. The tumor was mainly located at the gastric serosa and subserosa, and its growth pattern was expansile with entrapping of muscularis propria and submucosa in the periphery of the tumor. By immunohistochemistry, the tumor cells were diffusely positive for CD34 and vimentin but negative for cytokeratin, desmin, smooth muscle actin, CD99 and c-kit. Although its occurrence is rare, SFT should be considered in the differential diagnosis of mesenchymal tumors of the stomach. 相似文献
997.
A cell adhesive peptide moiety, Gly-Arg-Gly-Asp-Tyr (GRGDY), was immobilized onto the surface of highly porous biodegradable polymer scaffolds for enhancing cell adhesion and function. A carboxyl terminal end of poly(D,L-lactic-co-glycolic acid) (PLGA) was functionalized with a primary amine group by conjugating hexaethylene glycol-diamine. The PLGA-NH2 was blended with PLGA in varying ratios to prepare films by solvent casting or to fabricate porous scaffolds by a gas foaming/salt leaching method. Under hydrating conditions, the activated GRGDY could be directly immobilized to the surface exposed amine groups of the PLGA-NH2 blend films or scaffolds. For the PLGA blend films, the surface density of GRGDY, surface wettability change, and cell adhesion behaviors were characterized. The extent of cell adhesion was substantially enhanced by increasing the blend ratio of PLGA-NH2 to PLGA. The level of an alkaline phosphatase activity, measured as a degree of cell differentiation, was also enhanced as a result of the introduction of cell adhesive peptides. 相似文献
998.
Since the diagnosis of extrapulmonary tuberculosis (EPT) is largely depended on the physician's suspicion in respect of the disease, we believed that it would be worthwhile to scrutinize the clinical characteristics of EPT. Thus, here we present retrospectively evaluated clinical manifestations of patients who were diagnosed as EPT cases in a tertiary referral care hospital. Medical records of 312 patients, diagnosed as having EPT at Yongdong Severance hospital from January 1997 to December 1999, were reviewed retrospectively. In total 312 patients, 149 (47.8%) males and 163 (52.2%) females aged from 13 years to 87 years, were included into this study. The most common site of the involvement was pleura (35.6%). The patients complained of localized symptoms (72.4%) more frequently than systemic symptoms (52.2%). The most common symptom was pain at the infected site (48.1%). Leukocytosis, anemia, and elevated erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were found in 12.8%, 50.3%, 79.3% and 63.1% of the patients, respectively. Twenty-four percent of the patients had underlying medical illnesses such as, diabetes mellitus or liver cirrhosis, or were over 60 years old. In 67.3% of patients, tuberculosis was suspected at the initial visit. However, tuberculosis was microbiologically proven in only 23.7% of the patients. The time interval from the symptom onset to the diagnosis varied, with the mean duration of the period 96 days. Pulmonary parenchymal abnormal lesions were found in 133 patients (42.6%) on chest radiographs. EPT has a wide spectrum of clinical manifestations, so it is difficult to diagnose it. Based on our studies, only 11.2% of the patients were confirmed as EPT. So it is important that the physician who first examines the patient should have a high degree of suspicion based on the chest radiography, localized or systemic symptoms and several laboratory parameters reviewed in this study. 相似文献
999.
Imaging findings of secondary hepatic lymphoma have been reported as variable, ranging from single or multiple small nodules to diffuse infiltrative tumor patterns. We hear present a rare case report concerning aggressive B cells, secondary Burkitt's lymphoma in non-AIDS demonstrating a surprising periportal lymphoma infiltration, without upper abdominal lymphadenopathy or splenomegaly on the sonography and CT scans. Clinically, the case was characterized by atypical and highly aggressive course, with the patient presenting an abruptly developed obstructive jaundice with rapidly deteriorating hepatic function that could be indicative of cholestatic hepatitis, which differs in its clinical manifestations from hepatic lymphoma without functional deterioration in respect of its non-tissue destructive growth pattern. We suggest that hepatic lymphoma can sometimes be consistent with periportal infiltrating homogeneous mass, with no lymphadenopathy or splenomegaly on the imaging examination, with a predictable aggressive clinical course of the disease and poor prognosis. 相似文献
1000.
Association of Angiotensin-converting enzyme and angiotensinogen gene polymorphisms with preeclampsia 总被引:4,自引:0,他引:4
Choi H Kang JY Yoon HS Han SS Whang CS Moon IG Shin HH Park JB 《Journal of Korean medical science》2004,19(2):253-257
We tested the hypothesis that angiotensin-converting enzyme (ACE) and angiotensinogen gene polymorphism influence the incidence, development and outcome of preeclampsia. Subjects were recruited from 90 Korean patients with preeclampsia during pregnancy and 98 age-matched controls. After isolation of DNA, polymerase chain reactions (PCR) were carried out to detect polymorphism of the ACE and angiotensinogen. M235T and T174M genotypes of angiotensinogen were determined by digestion with restriction enzyme endonuclease Tth 111-I and NCo I, respectively. The frequency of DD genotype was significantly greater in preeclampsia (0.36) than in controls (0.14) (p<0.05). The frequency of D allele was 0.55 in preeclampsia and 0.40 in controls (p<0.05). There were no differences in the onset of preeclampsia and pregnancy outcomes according to the ACE genotypes. There was no difference in the frequency of a allele of angiotensinogen M235T between the groups (0.79:0.78 in preeclampsia : controls). The frequency of T allele of angiotensinogen T174M gene was slightly increased, but not significantly, in preeclampsia (0.11) than in controls (0.07). In a multivariate analysis, only ACE genotype was associated with the development of preeclampsia (beta=0.27, p=0.05). In conclusion, a molecular variant of ACE, but not angiotensinogen, gene is associated with preeclampsia in Korean women. 相似文献