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41.
To assess whether platelets are activated in transient global amnesia (TGA) and TIA, blood samples were analyzed by fluorescence-activated cytoscan using antibodies specific for platelet fibrinogen receptor (PAC1) and P-selectin (CD62P). Samples from TIA contained high levels of CD62P compared with age-matched control subjects, whereas those from TGA did not. The authors suggest that activated platelets are involved in brain ischemia, whereas ischemia appears not to be associated with most TGA. 相似文献
42.
Physical activity and risk of endometrial cancer in the Norwegian Women and Cancer (NOWAC) study 下载免费PDF全文
Kristin B. Borch Elisabete Weiderpass Tonje Braaten Mie Jareid Oxana A. Gavrilyuk Idlir Licaj 《International journal of cancer. Journal international du cancer》2017,140(8):1809-1818
Few studies have investigated the association between endometrial cancer and physical activity (PA) using repeated measures of PA and different subtypes of endometrial cancer. We aimed to investigate the association between endometrial cancer and PA level at two points in time in women with different body mass index (BMI) profiles, and to calculate the population attributable fraction (PAF) of endometrial cancer for low PA levels. We included 82,759 women with complete information on PA at baseline in the Norwegian Women and Cancer Study; 52,370 had follow‐up information on PA. 687 endometrial cancer cases were identified. Multivariate cox proportional hazard models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI). The PAF indicated the proportion of endometrial cancer that could be avoided in the population if these women had a higher PA level. There was a statistically significant association between low PA levels at baseline and follow‐up and endometrial cancer risk, with a dose‐response trend (lowest PA level: HR = 1.60, 95% CI 1.16–2.20; highest PA level: HR = 0.73, 95% CI 0.45–1.16 compared to the median). Analyses that included follow‐up measurements yielded similar results. 21.9% (95% CI 7.1–34.3) of endometrial cancers could be avoided if women with low PA levels (≤ 4 in a 1–10 degree self reported PA scale) increased their PA levels to 5‐10. We found an inverse dose‐response association between PA and endometrial cancer, independent of BMI. In this nationally representative cohort, 21.9% of endometrial cancers could potentially be avoided if PA levels increased to higher PA levels. 相似文献
43.
Mie Ishii Hiroshi Masuoka Yoshiharu Emi Takuya Mori Masaaki Ito Takeshi Nakano 《Circulation journal》2003,67(5):470-472
A 26-year-old man had been diagnosed with a cardiac murmur from birth. In 1998, he was admitted to hospital because of slight fatigue. A grade 5/6 continuous murmur was audible near the right sternal border at the second intercostal space. Doppler echocardiography detected an abnormal flow that suggested that an aneurysm of the right coronary sinus of Valsalva had ruptured into the right ventricular inflow tract. Blood tests showed a 19% step-up in oxygen saturation value between the right atrium and right ventricle, indicating a ventricular septal defect with left to right shunt. Coronary angiography revealed a single coronary artery. Surgical repair was carried out and the patient made an uneventful recovery. This rare combination of a ruptured aneurysm of the sinus of Valsalva coexisting with a ventricular septal defect and a single coronary artery has not been reported previously. 相似文献
44.
45.
Kazue Shiozawa Manabu Watanabe Takashi Ikehara Ryo Shimizu Mie Shinohara Yoshinori Igarashi Yasukiyo Sumino 《Journal of Medical Ultrasonics》2017,44(1):101-107
Purpose
To determine the usefulness of arrival time parametric imaging (AtPI) using contrast-enhanced ultrasonography (CEUS) with Sonazoid in evaluating early response to sorafenib for hepatocellular carcinoma (HCC).Methods
Twenty-one advanced HCC patients with low α-fetoprotein (AFP) levels (≤35 ng/ml) who received sorafenib for at least 4 weeks were enrolled in this study. CEUS was performed before and 2 weeks after treatment, and the images of the target lesion in the arterial phase were analyzed by AtPI. In the color mapping images obtained by AtPI, the mean arrival time of the contrast agent in the target lesion from the reference point (mean time: MT) was calculated. In each patient, differences between MT before and MT 2 weeks after treatment were compared. MT (+) and MT (?) groups were defined as difference of 0 s or greater and less than 0 s, respectively. Overall survival was evaluated between the two groups.Results
In the MT (+) (11 patients) and MT (?) (10 patients) groups, the median survival time was 792 and 403 days, respectively, which was statistically significant.Conclusions
The results suggested that AtPI was useful for evaluating early response to sorafenib for advanced HCC with low AFP level.46.
The epidemiology of lymphangioleiomyomatosis in Japan: a nationwide cross-sectional study of presenting features and prognostic factors 总被引:1,自引:0,他引:1
Hayashida M Seyama K Inoue Y Fujimoto K Kubo K;Respiratory Failure Research Group of the Japanese Ministry of Health Labor Welfare 《Respirology (Carlton, Vic.)》2007,12(4):523-530
BACKGROUND AND OBJECTIVE: To evaluate the characteristics and prognostic factors of Japanese patients with lymphangioleiomyomatosis (LAM). METHODS: A nationwide survey to identify patients with LAM was conducted by questionnaire. Survival probability was estimated using the Kaplan-Meier method, and the prognostic factors were analysed by Cox regression. RESULTS: Data were collected on 173 patients with pulmonary LAM. The major presenting features were pneumothorax (43%) and exertional dyspnoea (37%). The survival probabilities for patients presenting with exertional dyspnoea (Group A) were 85%, 60% and 47% after 5, 10 and 15 years, respectively, and for patients presenting with pneumothorax (Group B) were 95%, 89% and 89%, respectively. Although the age at symptom onset was higher among patients in Group A than in Group B, Cox regression revealed that the presenting feature was a prognostic factor independent of age at symptom onset (Group A/B hazard ratio = 5.732, P < 0.01). In the subgroup of patients whose initial FEV(1) was >1000 mL, or FEV(1)/FVC >40%, or %DL(CO) >40%, the rate of deterioration in these tests was greater in Group A than in Group B (P < 0.01 for FEV(1), P < 0.05 for FEV(1)/FVC and %DL(CO)). CONCLUSIONS: There are two possible subgroups of LAM patients. One subgroup that presented with pneumothorax, had onset of symptoms at a younger age and a more favourable prognosis; the other presented with exertional dyspnoea, had onset of symptoms at an older age and a poorer prognosis. 相似文献
47.
Although autoimmune processes may take place in human polymyositis, little is known with regard to its pathogenesis due to the lack of appropriate animal models. In the present study, we developed experimental autoimmune myositis (EAM) in Lewis rats by immunization with recombinant skeletal C-protein and examined the role of pathogenic T cells and autoantibodies. Using recombinant proteins and synthetic peptides, we demonstrated that skeletal C-protein Fragment 2 (SC2) has the strongest myositis-inducing ability and that myositis-inducing epitope(s) reside within the residues 334-363 of SC2 (SC2P3). However, immunization with SC2P3 induced only mild EAM compared with SC2 immunization. Characterization of T cells and antisera revealed that SC2P3 and SC2P7 contain the B cell epitope, while the T cell epitope resides in SC2P5. Furthermore, anti-SC2, but not anti-SC2P3, antisera contained antibodies against the conformational epitope(s) in the SC2 molecule. However, SC2P3 or SC2P5 immunization plus anti-SC2 antibody transfer aggravated the disease only slightly. These findings suggest that C-protein-induced EAM is formed by activation of C-protein-specific T cells along with antibodies against conformational epitopes in C-protein but that there are undetermined factors related to the disease progression. Further analysis of C-protein-induced EAM will provide useful information to elucidate the pathomechanisms of human polymyositis. 相似文献
48.
The aggregation of alpha-synuclein (alphaS) in the brain has been implicated as a critical step in the development of Lewy body diseases (LBD) and multiple system atrophy (MSA). Among the antioxidant strategies proposed, increasing evidence points to the possibility of achieving neuroprotection by dopamine agonists, as well as monoamine oxidase B inhibitors. We showed previously that the anti-Parkinsonian agents dose-dependently inhibited beta-amyloid fibrils (fAbeta)(1-40) and fAbeta(1-42) formation as well as destabilized preformed fAbetas. Using fluorescence spectroscopy with thioflavin S, electron microscopy, and atomic force microscopy, we examined the effects of anti-Parkinsonian agents, selegiline, dopamine, pergolide, bromocriptine, and trihexyphenidyl on the formation of alphaS fibrils (falphaS) and on preformed falphaS. All molecules except for trihexyphenidyl, dose-dependently inhibited the formation of falphaS. Moreover, these molecules dose-dependently destabilized preformed falphaS. The overall activity of the molecules examined was in the order of: selegiline = dopamine > pergolide > bromocriptine. These agents and other compounds related structurally could be key molecules for the development of therapeutics for LBD and MSA. 相似文献
49.
AbouZahr C Cleland J Coullare F Macfarlane SB Notzon FC Setel P Szreter S;Monitoring of Vital Events 《Lancet》2007,370(9601):1791-1799
Good public-health decisionmaking is dependent on reliable and timely statistics on births and deaths (including the medical causes of death). All high-income countries, without exception, have national civil registration systems that record these events and generate regular, frequent, and timely vital statistics. By contrast, these statistics are not available in many low-income and lower-middle-income countries, even though it is in such settings that premature mortality is most severe and the need for robust evidence to back decisionmaking most critical. Civil registration also has a range of benefits for individuals in terms of legal status, and the protection of economic, social, and human rights. However, over the past 30 years, the global health and development community has failed to provide the needed technical and financial support to countries to develop civil registration systems. There is no single blueprint for establishing and maintaining such systems and ensuring the availability of sound vital statistics. Each country faces a different set of challenges, and strategies must be tailored accordingly. There are steps that can be taken, however, and we propose an approach that couples the application of methods to generate better vital statistics in the short term with capacity-building for comprehensive civil registration systems in the long run. 相似文献
50.
Human combinatorial libraries yield rare antibodies that broadly neutralize hepatitis C virus 总被引:3,自引:1,他引:2
Johansson DX Voisset C Tarr AW Aung M Ball JK Dubuisson J Persson MA 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(41):16269-16274
One way to dissect the antibody response to an invading microorganism is to clone the antibody repertoire from immune donors and subsequently characterize the specific antibodies. Recently, methodological advances have allowed investigations of neutralizing antibodies against hepatitis C virus (HCV) in vitro. We have investigated three human mAbs, previously isolated from an individual infected with HCV of genotype 2b, that are known to cross-react in a binding assay to the envelope E2 protein of genotypes 1a and 1b. We now report that two of them have a neutralizing activity with a breadth not previously observed. Indeed, mAbs 1:7 and A8 recognized E2 from all of the six major genotypes, and they neutralized retroviral pseudoparticles [HCV pseudoparticles (HCVpp)] carrying genetically equally diverse HCV envelope glycoproteins. Importantly, these antibodies were also able to neutralize the cell culture infectious HCV clone JFH-1 in vitro, with IC(50) values of 60 ng/ml and 560 ng/ml, respectively. The conformational epitopes of these two broadly reactive antibodies were overlapping yet distinct and involved amino acid residues in the 523-535 region of E2, known to be important for the E2-CD81 interaction. The third antibody clone, representing a dominant population in the initial screen for these antibodies, was less broadly reactive and was unable to neutralize the genotype 2a infectious clone JFH-1. Our results confirm at the clonal level that broadly neutralizing human anti-HCV antibodies can be elicited and that the region amino acids 523-535 of the HCV envelope glycoprotein E2 carries neutralizing epitopes conserved across all genotypes. 相似文献