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排序方式: 共有6289条查询结果,搜索用时 15 毫秒
51.
Schwartz J Litonjua A Suh H Verrier M Zanobetti A Syring M Nearing B Verrier R Stone P MacCallum G Speizer FE Gold DR 《Thorax》2005,60(6):455-461
BACKGROUND: Particulate air pollution has been associated with increased cardiovascular deaths and hospital admissions. To help understand the mechanisms, the types of particles most involved, and the types of persons most susceptible, the association between exposure to summertime air pollution and heart rate variability (HRV) was examined in a panel study of 28 elderly subjects. METHODS: Subjects were seen once a week for up to 12 weeks and HRV (SDNN, r-MSSD, PNN50, low frequency/high frequency ratio (LFHFR)) was measured for approximately 30 minutes at each session using a defined protocol. Temperature, day of the week, and hour of the day were controlled, and dummy variables for each subject were controlled for subject specific risk factors. RESULTS: PM2.5 was associated with r-MSSD (-10.1% change for an interquartile range (IQR) increase in exposure (95% CI -2.8 to -16.9)) and PNN50, but stronger associations were seen with black carbon, an indicator of traffic particles, which was also associated with SDNN (-4.6% per IQR (95% CI -2.0 to -7.2)) and LFHFR. Secondary particles were more weakly associated with r-MSSD, as was ozone. No associations were seen with SO2 or NO2. CO had similar patterns of association to black carbon, which disappeared after controlling for black carbon. Black carbon had a substantially higher effect on SDNN in subjects who had had a previous myocardial infarction (-12.7%, 95% CI -5.7 to -19.25). CONCLUSIONS: Particles, especially from traffic, are associated with disturbances of autonomic control of the heart. 相似文献
52.
BACKGROUND: The current study attempted to evaluate the association between IL-10 promoter gene polymorphism and transplant outcomes including the occurrence of chronic graft-versus-host disease (GVHD) and its clinical course during systemic immunosuppressive treatment (IST) among 60 recipients of cytokine-mobilized peripheral blood stem cell (PBSC) from HLA-matched sibling donors. METHODS: We analyzed 3 single-nucleotide polymorphisms in proximal region of IL-10 promoter gene (-1082/-819/-592). RESULTS: In the current study, only two haplotypes (1082*A/819*T/592*A [ATA] and 1082*A/819*C/592*C [ACC]) were found. An increased occurrence of chronic GVHD was noted dependent on the IL-10 haplotypes (43% vs. 68% vs. 96% in ACC/ACC vs. ATA/ACC vs. ATA/ATA haplotype, P=0.003). In a logistic regression based on multinomial model, ATA/ATA homozygote had 7-fold increasing risk of the development of chronic GVHD compared with ACC/ACC homozygote. The incidence of chronic GVHD at 1 year was 46%+/-20%, 64%+/-10%, and 82%+/-5% in ACC/ACC, ATA/ACC and ATA/ATA group, respectively (P=0.0266). Plus, the duration of systemic IST was significantly shorter in recipients without ATA-haplotype comparing with those with ATA haplotype (339 days vs. 1,146 days, P=0.0091). CONCLUSION: IL-10 promoter gene polymorphism was found to be apparently associated with chronic GVHD after allogeneic peripheral blood stem cell transplantation from HLA-matched sibling donors. 相似文献
53.
Outcome of hepatic resection for metastatic gastric cancer 总被引:1,自引:0,他引:1
The role of hepatic resection for metastatic gastric cancer is less well defined due to the tendency of gastric cancer to widely metastasize. The purpose of this study is to examine the beneficial effect of hepatic resection in patients with metastatic gastric cancer. The clinicopathologic features and long-term results of 11 patients who underwent hepatic resection for metastatic gastric cancer from January 1988 to December 1996 at Seoul National University Hospital were analyzed retrospectively. All resected hepatic metastases were solitary lesions. Among eight patients with synchronous hepatic metastases, one patient with early gastric cancer and lymph node metastases (T1N2M1) remained alive for 8 years 6 months after hepatic resection without recurrence. Among three patients with metachronous hepatic metastases, two patients with advanced gastric cancer and lymph node metastases (T3N2MO, T2N1MO at the initial operation, respectively) survived 8 years 6 months and 3 years after hepatic resection, respectively. Median survival times of synchronous and metachronous hepatic metastases were 13.0 and 74.3 months, respectively. In solitary hepatic metastatic lesions from gastric cancer, surgical resection should be considered as one of the treatment options. 相似文献
54.
Treatment outcomes of intensity‐modulated radiotherapy versus 3D conformal radiotherapy for patients with maxillary sinus cancer in the postoperative setting 下载免费PDF全文
55.
Suh JS Cho J Lee SH Shin KH Yang WI Lee JH Cho JH Suh KJ Lee YJ Ryu KN 《Skeletal radiology》2000,29(12):680-689
Objective. To present the MR and angiographic findings of alveolar soft part sarcoma (ASPS).
Design and patients. MR examinations (12 tumors of 10 patients) of ASPS performed at multiple hospitals were retrospectively reviewed. The tumors
were found in the thigh (n=4), lower leg (n=4), femur (n=2, local metastasis), scalp (n=1) and arm (n=1). The MR signal characteristics including signal intensity, homogeneity and signal void of lesions and bony invasion including
direct invasion or local metastasis were evaluated. Angiographic findings (n=4) and post-embolotherapy follow-up MR imaging (n=2) findings were also assessed.
Results. Local bony metastasis was found in two cases. Seven tumors showed heterogeneous high signal intensity on T1- and T2-weighted
images with good enhancement. One tumor had a very high signal on T1-weighted images. Eight tumors (67%) showed numerous signal
voids in or near the tumors. All four angiographic studies showed numerous enlarged vessels, arteriovenous shunts and delayed
washout. Two cases mimicked arteriovenous malformations on angiographic studies but MR images demonstrated solid soft tissue
components as well as tortuous vessels.
Conclusions. High signal on T1-weighted image and numerous signal voids are highly suggestive of ASPS, although they are not universal
as has been suggested and arteriovenous malformation should be included in the differential diagnosis. Local bony metastases
in ASPS were seen in two cases and should be carefully investigated.
Received: 12 April 2000 Revision requested: 27 June 2000, 8 August 2000 Revision received: 2 August 2000, 21 August 2000 Accepted:
22 August 2000 相似文献
56.
PURPOSE: We prospectively evaluated the efficacy of a combination of desmopressin and oxybutynin for treating children with nocturnal enuresis, compared to the single drugs imipramine and desmopressin. MATERIALS AND METHODS: We enrolled 158 patients from 2003 to 2004. Children were randomly assigned to 1 of 3 groups and treated with desmopressin, imipramine or a combination of desmopressin plus oxybutynin. Of these patients 145 (100 boys and 45 girls, mean age 7.8 +/- 2.5 years, range 5 to 15) were followed for more than 6 months. Efficacy was measured at 1, 3 and 6 months in terms of average enuretic frequency, 5-scale response based on change in nocturnal enuretic frequency after treatment and posttreatment enuretic frequency as a percentage of pretreatment baseline frequency. The latter efficacy was classified according to daytime voiding symptoms. Statistical evaluation was performed using chi-square tests and ANOVA. RESULTS: Of the 145 children followed 48 received combination therapy, 49 received desmopressin and 48 received imipramine. A total of 68 patients (47%) had monosymptomatic enuresis and 77 (53%) had polysymptomatic enuresis. Combination therapy produced the best and most rapid results regardless of whether the children had monosymptomatic or polysymptomatic enuresis. CONCLUSIONS: Combination therapy with desmopressin plus oxybutynin for the treatment of pediatric nocturnal enuresis was well tolerated, and gave significantly faster and more cost-effective results than single drug therapy using either desmopressin or imipramine. 相似文献
57.
Weon Wook Park Kuen Tak Suh Jeung Il Kim Seong-Jang Kim Jung Sub Lee 《European spine journal》2009,18(12):1920-1926
Generalized low bone mass and osteopenia in both axial and peripheral skeletons have been reported in adolescent idiopathic
scoliosis (AIS). However, the mechanism and causes of bone loss in AIS have not been identified. Therefore, this study examined
the relationship between the osteogenic and adipogenic differentiation abilities of mesenchymal stem cells (MSCs) and bone
mass in 19 patients with AIS and compared these with those of 16 age- and gender-matched patients with lower leg fracture.
Mean lumbar spinal bone mineral density (LSBMD) in AIS patients was found to be lower than in controls (P = 0.037) and the osteogenic differentiation abilities and alkaline phosphatase activities of MSCs from patients were also
found to be lower than those of controls (P = 0.0073 and P = 0.001, respectively), but the abilities of the MSCs of patients and controls to undergo adipogenic differentiation were
similar. The osteogenic differentiation ability was found to be positively correlated with alkaline phosphatase activity in
the AIS group. However, the osteogenic and adipogenic abilities were not found to be correlated with LSBMD in either patients
or controls. These findings suggest that the decreased osteogenic differentiation ability of MSCs might be one of the possible
mechanisms leading to low bone mass in AIS. However, we did not determine definite mechanisms of low bone mass in AIS. Therefore,
further study with large scale will be needed to identify the mechanism involved. 相似文献
58.
59.
We report an unusual case of a chronic prosthetic dislocation that was caused by the buttonholing of a prosthetic femoral head by anterior soft tissue, which impeded reduction. A surprisingly good functional result was achieved by an open reduction and revision operation on a 56-year-old man, who had a chronic dislocation of a total hip prosthesis. Successful treatment with open reduction of a chronic proximal dislocation after total hip arthroplasty has not been reported previously in the literature. 相似文献
60.
Facet joint violation during pedicle screw insertion: a cadaveric study of the adult lumbosacral spine comparing the two pedicle screw insertion techniques 下载免费PDF全文
This article analyses the incidence of facet joint violation by pedicle screws inserted via the two most commonly used techniques, intersection and mammillary. Pedicle screws were inserted on each side of fresh-frozen human cadevaric specimen lumbosacral spines using the two techniques. All facet joints which were violated were found to be on the right side, where the mamillary process technique was employed. The incidence of facet joint violation was higher in the mammillary technique, which was statistically significant. The intersection technique appears to be safer than the mamillary with respect to violation of the adjacent superior facet joint. 相似文献