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排序方式: 共有482条查询结果,搜索用时 31 毫秒
61.
Chiau-Suong Liau 《Geriatrics & Gerontology International》2004,4(S1):S304-S306
In Taiwan, the percentage of the population 65 years of age or older increased regularly, from 3.08% in 1972 to 8.8% in 2001. Taiwan started the national health insurance system in 1995. The aged population utilized a large share of the medical resources, for example 28.73% of the total national medical expenditures in 2000. Cardiovascular diseases are common causes of mortality in Taiwan. Cerebrovascular diseases, heart diseases and hypertensive diseases, held the second, third and 10th positions, respectively, among the 10 leading causes of mortality in 2002, in Taiwan. The mortality rates of cerebrovascular diseases and heart diseases are decreasing, while that of malignant neoplasms and diabetes mellitus are increasing, as evidenced over the past 2 decades. Cerebral hemorrhage is relatively common in Taiwan. As demonstrated in a series, of the 10 772 hospitalized acute stroke cases, 35.4% were diagnosed as cerebral hemorrhage. Hypertension is highly prevalent in the elderly population in Taiwan, more than 55% for both sexes, as indicated by some epidemiologic studies. There are few studies on the prevalence of heart diseases in the elderly population in Taiwan. One large-scale epidemiologic study demonstrated that the prevalence rates of coronary artery disease (CAD) among the elderly population, were 12.3% for males and 10.2% for females. The biostatistic data indicated that, in Taiwan, the mortality due to CAD was rapidly increasing in the 1970s and 1980s and reached a plateau in the 1990s. It is concluded that cardiovascular diseases are common causes of morbidity and mortality in elderly people in Taiwan. Although mortality due to cerebrovascular diseases and heart diseases have decreased over past decades, the mortality due to coronary artery disease is still at the peak level. 相似文献
62.
Tseng GS Liau GS Shyu HY Chu SJ Ko FC Wu KA 《Diagnostic and interventional radiology (Ankara, Turkey)》2012,18(1):139-141
Rectus sheath hematoma is an uncommon but well-described complication of a tussive paroxysm. It is an accumulation of blood within the sheath of the rectus abdominis secondary to disruption of the epigastric vessels or the rectus muscle and is often misdiagnosed as acute abdomen. Increases in the number of elderly patients and the use of therapeutic anticoagulation may increase the prevalence and severity of rectus sheath hematomas encountered in clinical practice. Expanding rectus sheath hematomas are occasionally refractory to conservative treatment and may require hemostatic intervention. Here, we describe the case of an 87-year-old woman who presented with two separate rectus sheath hematomas that were precipitated by a paroxysm of coughing. Repeated computed tomography showed two separate expanding rectus sheath hematomas, which were not accompanied by obvious contrast extravasation on angiography. Empiric left inferior epigastric artery embolization resulted in rapid hemodynamic stabilization, and the hematomas shrank gradually. Early empiric transcatheter arterial embolization may be appropriate for patients who are poor surgical candidates and have enlarging hematomas that are refractory to conservative treatment. 相似文献
63.
Background
The “180° turning and sitting down task” is a very conscious movement that requires focusing on turning at the exact moment, and very few studies address on this topic in older adults. The purpose of the study was to compare kinematics and electromyography of the head, lumbar and knee joints during 180°turning in older and young adults.Methods
Twenty older adults and 20 younger adults were assessed. A 16-channel telemetry electromyography system with electrogoniometers and an inclinometer were used to record the head, lumbar and knee joint kinematic and electromyography data during the 180° turning. This movement had been further divided into 4 phases (braking, mid-stance, swing, and terminal loading) for analysis.Findings
There were significant differences in the joint displacement and muscular activity among the different phases. Comparison between groups showed that the older adults group had less lateral lumbar flexion, less knee flexion and lower velocity of the head and knee flexion compared to young adults during turning. The electromyography data of the left biceps femoris, left gastrocnemius and left erector spinae muscles in the older adults group showed significantly higher levels than in the young adults.Interpretation
Older adults need to adjust velocities of moving joints and increase the extensor synergy muscles of the back and the stance leg to provide posture stability. Kinematics and neuromuscular modulations of the head, lumbar and knee are required according to the various phases of the turn movements and change with aging. 相似文献64.
Chin-Kan Chan Ming-Ling Kuo Jiann-Jong Shen Lai-Chu See Hen-Hong Chang Jing-Long Huang 《Pediatric allergy and immunology》2006,17(5):316-322
Traditional Chinese medicine has a long history of application in the treatment of bronchial asthma. Solid scientific evidence, however, is not available despite its widespread use among patients worldwide and in Taiwan. To assess the effect of Ding Chuan Tang (DCT) in airway hyper-responsiveness (AHR) on asthmatic children via randomized, double blind, placebo-controlled clinical trial. This study enrolled children who were aged 8-15 and diagnosed as mild to moderate persistent asthma patients. They were randomly allocated to receive 6.0 g DCT or placebo daily for 12 wk. Self-recorded daily symptom scores, medication scores, and morning and evening peak expiratory flow rates were returned at the monthly clinic. Pulmonary function test, methacholine challenge test, and serum inflammatory mediators were measured before and at the end of the trial. Fifty-two asthmatic children completed the clinical study. Twenty-eight patients were assigned to the treatment group and 24 to the placebo group. At the end of the treatment period, AHR determined by log PC(20) was significantly improved in the DCT group (0.51 +/- 1.05 mg/ml vs. 0.26 +/- 0.84 mg/ml, p = 0.034). The total clinical and medication reduced parameters showed improvement in the DCT group (p = 0.004). The AHR, symptom and medication scores in children with persistent asthma were significantly improved with DCT treat for 12 wk. The results suggested more stable airways achieved with such an add-on complementary therapy. 相似文献
65.
The literature indicates that some mechanism other than the interferon or host-mediated immune enhancement might also be responsible for an antitumor effect of polyinosinate-polycytidylate [poly(I)-poly(C)]. We have examined the effect of this drug on the synthesis of ribosomes and other macromolecules in a rat tumor, the Novikoff ascites hepatoma. The nucleolus was one of the primary targets affected by the administration of poly(I)-poly(C) in vivo. A progressive decline of the activity of nucleolar ribosomal RNA methylases began within 2 hr, followed by a decline of the nucleolar RNA content. The activity of nucleolar RNA polymerase was inhibited only at later time intervals. Labeling of tumor macromolecules in vivo revealed that the methylation of ribosomal RNA and the production of ribosomes, particularly in the small subunits, were immediately and progressively affected, followed by inhibition of the synthesis of DNA, RNA, and protein at later times. In addition, poly(I)-poly(C) also induced disaggregation of polyribosomes and restricted the movements of nuclear RNA to cytoplasm and of cytoplasmic protein to nucleus. These in vivo effects of poly(I)-poly(C) on tumor cells was observed neither on the host livers nor on livers of normal rats. Studies on isolated nucleoli showed that the in vitro addition of polyinosinate and several other compounds actively inhibited tumor ribosomal RNA methylases but were devoid of inhibitory effect against liver ribosomal RNA methylases; these results augment other studies in the literature in suggesting a selective effect of the polyinosinate moiety on tumor cells. We conclude from this study that initial impairment of the methylation of ribosomal precursor RNA, following exposure of tumor cells to poly(I)-poly(C), is responsible for the destruction of ribosomes, preferentially the small subunits, during the maturation processes. Failure to provide new ribosomes thus triggers the events limiting the growth of tumor cells. 相似文献
66.
Y H Liau B L Slomiany D Palmer D R Braun A Slomiany Z Jozwiak W S Rosenthal 《Digestion》1983,28(2):132-137
A sulfotransferase activity which catalyzes the transfer of sulfate group from 3'-phosphoadenosine-5'-phosphosulfate to galactosylceramide and triglucosyl monoalkylmonoacylglycerol has been demonstrated in antral and fundic mucosa of normal human stomach. With both types of mucosa maximum activity for sulfation of galactosylceramide was obtained at pH 6.8, whereas the pH optimum for sulfation of triglucosyl monoalkylmonoacylglycerol was 7.8. The reactions were stimulated by the addition of Triton X-100, Mg2+ and F1-. The sulfotransferase activity of fundic mucosa for the synthesis of sulfated glyceroglucolipid was about two times higher than that of antral mucosa, while the enzyme activity for sulfation of glycosphingolipid was similar in both areas of the stomach. 相似文献
67.
M F Chen Y T Lee H C Hsu P C Yeh C S Liau P C Huang 《International journal of cardiology》1992,35(3):323-331
We studied myocardial injury during acute coronary occlusion-reperfusion and atherosclerosis in rabbits fed a high cholesterol diet with or without fish oil supplementation. New Zealand white male rabbits were divided into 3 groups. Eight control rabbits fed with laboratory standard rabbit chow were group I. In addition to the standard chow, 15 rabbits fed with a 1% cholesterol-enriched diet for 6 weeks were group II, and 10 rabbits fed with a 1% cholesterol-enriched and 10% fish oil supplemented diet for 6 weeks were group III. Acute coronary occlusion was induced by ligating the marginal branch of the left circumflex coronary artery for 1 h, followed by reperfusion for 4 h. Myocardial injury was assessed by tissue creatine kinase activities and amino-nitrogen concentrations from the ischemic (infarct) and nonischemic (normal) myocardium, and the infarct area/risk area ratios of the left ventricle. The surface area of the atherosclerotic lesions of the aorta and pulmonary artery was measured by planimeter. There was significantly more myocardial loss of creatine kinase and amino-nitrogen in the cholesterol-fed rabbits than the controls (p less than 0.01 and 0.02, respectively). The cholesterol and fish oil-treated rabbits had a nonsignificant reduction in myocardial loss of both agents as compared to their corresponding cholesterol-fed ones. The same trend was also found in the infarct area/risk area ratio. Fish oil treated rabbits had a good effect on the reduction of atherosclerotic lesions and tissue cholesterol levels in the aorta and pulmonary artery, but not in the left ventricle.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
68.
Stem cells are commonly defined as undifferentiated cells capable of self-renewing and giving rise to a large number of differentiated progeny. It is becoming increasingly apparent that there exist cancer stem cells (CSCs) from which the cells of any given malignancy arise, whereby only a few cells out of a population of cancer cells are able to initiate tumor formation. These CSCs, like their normal counterparts, are characterized by self-renewal and the ability to "differentiate" into all of the cell types in the original tumor. Current chemotherapeutic strategies involve using non-specific cytotoxic agents that target rapidly cycling cells. Although this may reduce disease burden in many cases, these therapies may miss the rare, self-renewing population that truly gives rise to the malignancy (the CSC). This review will focus on the recent discovery of stem cell-like cells in human brain tumors, putative "brain cancer stem cells," which exhibit the properties of self-renewal and the ability to recapitulate the original tumor heterogeneity. Dissecting the molecular mechanisms that underlie the ability of these cells to self-renew and maintain quiescence may allow the development of novel therapeutic strategies that will allow for more efficacious and less toxic therapies for these devastating malignancies. 相似文献
69.
The clinical features and microbiological characteristics of 315 patients with definite or possible infective endocarditis (IE) from January 1995 to December 2003 were evaluated. There were 187 males and 128 females with a mean age of 51 years (range, 1 month to 92 years). Ninety-three patients (30%) had a diagnosis of valvular heart disease and 24 (8%) had received prosthetic valve replacement. Blood culture was negative in 62 patients (20%). Staphylococci (91 patients, 32%), including methicillin-susceptible Staphylococcus aureus (15%), methicillin-resistant S. aureus (11%), and coagulase-negative staphylococci (6%), were the most commonly encountered pathogens followed by viridans group streptococci (77 patients, 24%). Eight patients (25%) had various neurological, renal, embolic, and cardiac complications. Patients with neurological complications [odds ratio (OR) 8.175, P<0.001], nosocomial IE (OR 6.661, P<0.001), underlying malignancy (OR 4.993, P<0.001), elevated serum creatinine level (OR 3.132, P=0.001), or elevated WBC count (>15000/mm3) (OR 2.537, P=0.007) were at significantly increased risk of mortality. This study found mortality from IE was associated with several factors, among which neurological complications were the most hazardous. Patients with more than one risk factor had poorer prognosis. These results suggest the need for more aggressive management in patients with IE when multiple risk factors for mortality are identified. 相似文献
70.
Antagonism of sphingosine-1-phosphate receptors by FTY720 inhibits angiogenesis and tumor vascularization 总被引:12,自引:0,他引:12
LaMontagne K Littlewood-Evans A Schnell C O'Reilly T Wyder L Sanchez T Probst B Butler J Wood A Liau G Billy E Theuer A Hla T Wood J 《Cancer research》2006,66(1):221-231
FTY720, a potent immunomodulator, becomes phosphorylated in vivo (FTY-P) and interacts with sphingosine-1-phosphate (S1P) receptors. Recent studies showed that FTY-P affects vascular endothelial growth factor (VEGF)-induced vascular permeability, an important aspect of angiogenesis. We show here that FTY720 has antiangiogenic activity, potently abrogating VEGF- and S1P-induced angiogenesis in vivo in growth factor implant and corneal models. FTY720 administration tended to inhibit primary and significantly inhibited metastatic tumor growth in a mouse model of melanoma growth. In combination with a VEGFR tyrosine kinase inhibitor PTK787/ZK222584, FTY720 showed some additional benefit. FTY720 markedly inhibited tumor-associated angiogenesis, and this was accompanied by decreased tumor cell proliferation and increased apoptosis. In transfected HEK293 cells, FTY-P internalized S1P1 receptors, inhibited their recycling to the cell surface, and desensitized S1P receptor function. Both FTY720 and FTY-P apparently failed to impede VEGF-produced increases in mitogen-activated protein kinase activity in human umbilical vascular endothelial cells (HUVEC), and unlike its activity in causing S1PR internalization, FTY-P did not result in a decrease of surface VEGFR2 levels in HUVEC cells. Pretreatment with FTY720 or FTY-P prevented S1P-induced Ca2+ mobilization and migration in vascular endothelial cells. These data show that functional antagonism of vascular S1P receptors by FTY720 potently inhibits angiogenesis; therefore, this may provide a novel therapeutic approach for pathologic conditions with dysregulated angiogenesis. 相似文献