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11.
Ahn SH  Ahn MW  Byun WM 《Spine》2000,25(4):475-480
STUDY DESIGN: Magnetic resonance imaging of symptomatic herniated lumbar discs was investigated longitudinally and prospectively for the presence of tear in the posterior longitudinal ligament (PLL). OBJECTIVES: To clarify the effect of transligamentous extension through the PLL of herniated disc on its regression and to determine the factors contributing to a successful clinical outcome. SUMMARY OF BACKGROUND DATA: Greater regression of the herniated fragment has been noted with larger initial disc herniations. The exposure of herniated disc materials to the epidural vascular supply through the ruptured PLL has been suspected to play a part in the mechanism of disappearance of the herniated nucleus pulposus. However, it had not been shown clinically. METHODS: Clinical outcomes and magnetic resonance images of 36 patients with symptomatic lumbar disc herniations, treated conservatively, were analyzed. Patients were divided into three groups: subligamentous, transligamentous, and sequestered herniations. The size of the herniated disc was measured by herniation ratio, which is defined as the ratio of the area of herniated disc to that of the thecal sac on the axial view. Factors associated with the natural regression of herniated disc and the successful clinical outcome were explored. RESULTS: Of the 36 herniated discs, 25 decreased in size. Ten (56%) of 18 subligamentous herniations, 11 (79%) of 14 transligamentous herniations, and all 4 (100%) sequestered herniations were reduced in size. The average decreases in herniation ratio of the subligamentous, transligamentous, and sequestered disc groups were 17%, 48%, and 82% respectively. The decrease in herniation ratio was related to the presence of transligamentous extension but was not related to the initial size of herniation. Successful outcome correlated with a decrease in herniation of more than 20%. CONCLUSION: Transligamentous extension of herniated disc materials through the ruptured PLL is more important to its reduction in size than is the initial size of the herniated disc. Decrease in herniation ratio of more than 20% seems to correspond to successful clinical outcome.  相似文献   
12.
Expression of placental growth factor gene in lung cancer.   总被引:4,自引:0,他引:4  
Differences in the gene expression profiles in small cell lung cancers (SCLC) and non-small cell lung cancers (NSCLC) may explain their different clinical characteristics. The aims of this study were (1) to identify genes differentially expressed in SCLC and NSCLC using mRNA differential display, and (2) to determine the clinical relevance of such genes in lung cancer. RNA differential display using three SCLC and six non-SCLC cell lines was used to identify a differentially expressed gene. Differential expression of the gene was confirmed in additional lung cancer cell lines using RT-PCR. Immunohistochemical staining for the gene product was performed on paraffin-embedded tissue from lung cancer patients. We examined the relationship between the expression of the gene and clinical parameters, including disease stage, response to treatment and survival time. The placental growth factor (PGF) gene was identified as preferentially expressed in SCLC compared with NSCLC cell lines using mRNA differential display. Further analysis of 45 lung cancer cell lines using RT-PCR showed that the placental growth factor (PGF) gene was expressed in nine of 13 SCLC cell lines (69%) and five of 32 NSCLC cell lines (15.6%) (p < 0.001, Fisher's exact test). Immunohistochemistry using anti-PGF antibody on the paraffin blocks from lung cancer patients showed that PGF expression was significantly higher in SCLC than NSCLC tissue sections (32 vs. 5.6%, p = 0.041, Fisher's exact test). Expression of PGF protein did not correlate with disease stage, response to treatment or survival time in SCLC patients. The present study suggests there is higher expression of PGF in SCLC compared to NSCLC. It may be that higher expression of the angiogenic factor PGF contributes to differences between the progression of SCLC and NSCLC, especially in regard to the nature of SCLC metastasis.  相似文献   
13.
Five patients with avulsed scalps were treated with replantation between 1992 and 1998. All patients were women age 20 to 36 years. The percentage of the avulsed scalp ranged from 50% to 100% of the whole scalp. The vessels chosen for anastomosis were the superficial temporal artery, occipital artery, and superficial temporal vein. A vein graft harvested from the cephalic vein of the forearm was performed on the venous and arterial sides in 1 patient. Two patients experienced complete survival of the replanted scalp. Three patients showed 40%, 50%, and 80% survival areas, with the remaining defects resurfaced as split-thickness skin grafts. Six months later, the scar areas in the last 3 patients were reconstructed with an expansion of the normal or replanted scalp. The follow-up period ranged from 1 to 7 years. In 4 patients a partial return of sensation in the replanted scalp and motor function of the frontalis muscle were observed. All patients were satisfied with the aesthetic results of their surgery.  相似文献   
14.
Association of Helicobacter pylori Infection with Gastric Adenocarcinoma   总被引:2,自引:0,他引:2  
Gastric adenocarcinoma is the most prevalent cancer in South Korea, and Helicobacter pylori (H. pylori) infection is also common. This study was performed to examine the association between H. pylori infection and gastric cancer, taking into account various other factors. To investigate the association between gastric adenocarcinoma and H. pylori infection, determined by urease-positive reaction in the CLO test, a total of 175 paired specimens (175 tumor and 175 tissues adjacent to tumor) of stomach cancer patients and a total of 113 control specimens were obtained. The positive H. pylori infection rates were 78.9% (138/175) among the patients in specimens of tumor or tissues adjacent to the tumor and 41.6% (47/113) among controls in the CLO test. A positive correlation between H. pylori infection and gastric cancer was observed (age-adjusted odds ratio, 7.0; MH χ2=34.5 with P <0.0005). These data suggest that stomach cancer patients in Korea have high infection rates of H. pylori regardless of site specificity, and this infection might be causally associated with stomach cancer.  相似文献   
15.
A co-operative study was conducted to determine the clinical characteristics of patients with moyamoya disease who were diagnosed and treated at neurosurgical institutes in Korea before 1995. Twenty-six hospitals contributed 505 cases and among them, the clinical characteristics of 334 patients with definite moyamoya disease were evaluated. The number of patients began to increase from the late 1980s, and after that approximately 20 patients were treated each year. There were two age peaks: from six to 15 and from 31 to 40 years of age. Haemorrhagic manifestations occurred in approximately 43% of the patients. The major clinical manifestations were haemorrhage in adults (62.4%) and ischaemia in children (61.2%). Overall 54.5% of the patients experienced decreased consciousness levels, mainly due to intracranial haemorrhage or cerebral infarction. In the patients with ischemic manifestations, the adult patients were more likely to have cerebral infarction than the pediatric patients (80% vs. 39%) and the pediatric patients were more likely to have TIA (61% vs. 25%). Thirty eight percent of the patients underwent bypass surgery and 53% of these procedures were performed bilaterally. Treatment policies, including indications for bypass surgery and commonly used drugs, were somewhat different according to the institution. Overall favorable outcome was 73%, and the most significant factor affecting poor outcome was haemorrhagic manifestation. This article describes the characteristics of 334 patients with moyamoya disease, who were diagnosed and treated at neurosurgical institutes in Korea before 1995.  相似文献   
16.
Brenner tumor of the ovary: CT and MR findings   总被引:4,自引:0,他引:4  
PURPOSE: The purpose of this study was to determine the CT and MR characteristics of Brenner tumors, rare epithelial neoplasms of the ovary. METHOD: CT and MR scans of eight pathologically proven Brenner tumors of the ovary (seven benign, one malignant, and one associated with mucinous cystadenoma) were retrospectively reviewed. The masses were analyzed for location, size, external configuration, internal architecture, enhancement pattern, presence of calcification, and metastatic spread. RESULTS: The patients' median age was 63 years (range 39-79 years), and the mean size of the tumors was 11.4 cm (7.5-17 cm). All tumors were unilateral and had a well-defined margin. The mass was mostly solid in three, mostly cystic in one, and "mixed" solid and cystic in four cases. The tumors with cystic components (n = 5) were mostly multilocular in appearance (n = 4). All the solid components showed mild homogeneous enhancement on postcontrast CT and MRI. Extensive amorphous calcification within the solid component on CT was seen in five of six cases (83%). No characteristic findings discriminating malignancy from benign Brenner tumor could be found. CONCLUSION: Extensive amorphous calcification in a solid mass or solid component in a multilocular cystic mass is a characteristic finding of Brenner tumor of the ovary on CT and MRI.  相似文献   
17.
Prostate cancer is one of the most prevalent non-skin related cancers. It is the second leading cause of cancer deaths among males in most Western countries. If prostate cancer is diagnosed in its early stages, there is a higher probability that it will be completely cured. Prostatic acid phosphatase (PAP) is a non-specific phosphomonoesterase synthesized in prostate epithelial cells and its level proportionally increases with prostate cancer progression. PAP was the biochemical diagnostic mainstay for prostate cancer until the introduction of prostate-specific antigen (PSA) which improved the detection of early-stage prostate cancer and largely displaced PAP. Recently, however, there is a renewed interest in PAP because of its usefulness in prognosticating intermediate to high-risk prostate cancers and its success in the immunotherapy of prostate cancer. Although PAP is believed to be a key regulator of prostate cell growth, its exact role in normal prostate as well as detailed molecular mechanism of PAP regulation is still unclear. Here, many different aspects of PAP in prostate cancer are revisited and its emerging roles in other environment are discussed.  相似文献   
18.
19.
PurposeCurrently, there are multiple options for the pharmacological treatment of asthma. This study aimed to compare the effects of different asthma medications on exacerbation in a real-world setting.Materials and MethodsWe retrospectively reviewed electronic medical records of asthma patients who visited the hospital from November 1, 2016 to October 31, 2019. The number of asthma exacerbations requiring administration of systemic steroids was the primary outcome. A time-varying Cox regression analysis was used to reflect the real-world setting: variable usage times, discontinuation, and switching of medication.ResultsAmong 937 patients with asthma, 228 (24.3%) experienced asthma exacerbation during the study period. Asthma exacerbation was observed in patients using short-acting β2-agonists (SABA) alone (50.4% vs. 28.6%, p<0.001) as well as in patients not using inhaled corticosteroids (ICS) (58.8% vs. 40.3%, p<0.001), long-acting β2-agonists (LABA) (54.8% vs. 36.1%, p<0.001), and leukotriene receptor antagonists (71.5% vs. 50.8%, p<0.001). A time-varying Cox regression analysis of asthma exacerbations according to the duration of asthma medication showed that SABA alone increased the risk of asthma exacerbation [hazard ratio (HR), 1.834; 95% confidence interval (CI), 1.299–2.588; p=0.001], whereas ICS-LABA decreased the risk (HR, 0.733; 95% CI, 0.538–0.997; p=0.048). However, in the subgroup analysis according to medication type, specific ingredients showed no significant differences.ConclusionIn the real world, asthma medications affect asthma exacerbation variably according to the medication type.  相似文献   
20.
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