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排序方式: 共有3929条查询结果,搜索用时 15 毫秒
41.
Shumway-Cook A Patla A Stewart A Ferrucci L Ciol MA Guralnik JM 《Journal of the American Geriatrics Society》2003,51(3):393-398
OBJECTIVES: To examine the relationship between characteristics of the physical environment and mobility disability in community-living older persons. DESIGN: Cross-sectional study conducted on three groups of community-dwelling older adults. SETTING: Community-dwelling older people in Seattle, Washington, and Waterloo, Ontario, Canada. PARTICIPANTS: Fifty-four older adults (> or =70) were recruited from two geographic sites and grouped according to level of physical function (elite, physically able, physically disabled). MEASUREMENT: Subjects reported on frequency of encounter versus avoidance of 24 features of the physical environment, grouped into eight dimensions, using a five-point ordinal scale (never, rarely, sometimes, often, always). Never and rarely responses were combined and coded as not encountered or not avoided, whereas the sometimes, often or always responses were combined and coded as encountered or avoided. RESULTS: Disabled older adults reported fewer encounters with and concomitantly greater avoidance of physical challenges to mobility than nondisabled older adults. However, both encounter and avoidance varied by environmental dimension. CONCLUSION: Results support the hypothesis that mobility disability results from an interaction of individual and environmental factors. Mobility disability is associated with avoidance of some, but not all, physically challenging features within the environment, suggesting that some environmental features may disable community mobility more than others. 相似文献
42.
A molecular understanding of physiologic and pathologic processes requires complete knowledge about the signal transduction mechanism of involved cells. Signal transduction research is a rapidly growing field in basic science. Unlike intercellular inflammatory mediators, signaling molecules show less functional redundancy. This allows inhibition of multiple cytokines/mediators by blocking one common signaling molecule. Interference with signaling pathways has shown significant potential for inhibition of fundamental processes as well as clinical phenotype of allergic diseases. The purpose of this review was to provide a theoretical classification of signaling molecules based on their function and to analyze various strategies for developing effective signaling inhibitors for allergic diseases. 相似文献
43.
OBJECTIVE: Our aim was to review the clinical behavior of human papillomavirus (HPV)-associated digital squamous cell carcinoma (SCC). Specifically, we examined evidence for the tumor's (1) infectious origin and spread, (2) response to therapy, and (3) prognosis and metastatic risk. DESIGN: We reviewed and performed data tabulation of all 51 reported cases in the English-language literature and a case series of 23 cases (21 of them not previously reported). We present 2 of the cases in depth. SETTING: We used previously reported cases from MEDLINE and a case series from a single dermatologic operation practice from 1985 to 1999. RESULTS: (1) Of all cases, 10% (7/72) had an antecedent genital dysplasia or carcinoma containing the same HPV subtype as the digital SCC. (2) The rate of recurrence after general surgical therapy was 43% (6/14). After Mohs micrographic surgery the recurrence rate was 13% (2/16) for the cases in the literature, and 26% (6/23) for our case series. (3) Of tumors, 3% (2/72) have been observed to metastasize. CONCLUSIONS: (1) This suggests the possibility of genital-digital spread as a mechanism of tumor genesis. (2) HPV-associated digital SCC is more likely to recur after surgical treatment than previously reported. This rate of recurrence greatly exceeds that for cutaneous SCCs in general and may be caused by residual postsurgical HPV. (3) The rate of metastasis, however, appears to be low. 相似文献
44.
Many different suture techniques are routinely used by cutaneous surgeons for the closure of surgical wounds. This paper reviews several common suture techniques and their associated subtypes. In particular, for each technique, we discuss the method for placement, generally accepted indications, controversies regarding utility, and objective evidence of efficacy. 相似文献
45.
Understanding reactive recovery responses to slipping is fundamental in falls research and prevention. The primary purpose of this study was to investigate the role of the unperturbed limb and arms in the reactive recovery response to an unexpected slip. Ten healthy, young adults participated in this experiment in which an unexpected slip was induced by a set of steel free-wheeling rollers. Surface electromyography (EMG) data were collected from the unperturbed limb (i.e., the swing limb) rectus femoris, biceps femoris, tibialis anterior, and the medial head of gastrocnemius, and bilateral gluteus medius, erector spinae, and deltoids. Kinematic data were also collected by an optical imaging system to monitor limb trajectories. The first slip response was significantly different from the subsequent recovery responses to the unexpected slips, with an identifiable reactive recovery response and no proactive changes in EMG patterns. The muscles of the unperturbed limb, upper body, and arms were recruited at the same latency as those previously found for the perturbed limb. The arm elevation strategies assisted in shifting the center of mass forward after it was posteriorly displaced with the slip, while the unperturbed limb musculature demonstrated an extensor strategy supporting the observed lowering of the limb to briefly touch the ground to widen the base of support and to increase stability. Evidently a dynamic multilimb coordinated strategy is employed by the CNS to control and coordinate the upper and lower limbs in reactive recovery responses to unexpected slips during locomotion. 相似文献
46.
47.
Jasir A Kasprzykowski F Kasprzykowska R Lindström V Schalén C Grubb A 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2003,111(11):1004-1010
We describe the synthesis and antibacterial properties of a novel antimicrobial peptidyl derivative, (2S)-2-(Nalpha-benzyloxycarbonyl-arginyl-leucylamido-1-[(E)-cinnamoylamido]-3-methylbutane, structurally based upon the inhibitory centre of the human cysteine protease inhibitor, cystatin C. The derivative, here called Cystapep 1, displayed antibacterial activity against several clinically important gram-positive bacteria. It displayed minimal inhibitory and bactericidal concentrations of about 16 microg/ml for both Staphylococcus aureus and Streptococcus pyogenes. In radial agar diffusion assays, groups A, B, C and G streptococci as well as staphylococci were generally susceptible to the action of Cystapep 1, whereas pneumococci and enterococci were less susceptible. No activity against gram-negative bacteria was observed. Cystapep 1 also showed high activity against methicillin-resistant S. aureus (MRSA) and multiantibiotic-resistant coagulase-negative staphylococci (CNS), suggesting that its mechanism of action differs from those of most currently used antibiotics. 相似文献
48.
Background
Protease activated receptor-2 (PAR-2) has been implicated in cellular proliferation, invasion and metastasis in various tumors. Lymph node metastasis is an important patient prognostic factor for uterine cervical cancers. This prompted us to study the role of PAR-2 in lymph node metastasis of uterine cervical cancers. 相似文献49.
Silymarin isolated from Silybum marianum is a mixture of three isomers, silybin (1), silydianin (2) and silychristin (3). Silybin is the most active antihepatotoxic agent, and contains a 1,4-dioxane ring in addition to a flavonoid moiety. Based on the skeleton of silybin, we prepared some flavones and coumarins containing the 1,4-dioxane ring system and evaluated them for antihepatotoxic activity against carbon tetrachloride induced hepatotoxicity in albino rats. The degree of protection was determined by measuring biochemical parameters such as serum glutamic oxaloacetic transaminase (SGOT), serum glutamic pyruvate transaminase (SGPT), alkaline phosphatase (ALKP), total protein (TP) and total albumin (TA). The compounds namely 3',4'(1",4"-dioxino) flavone (4f), and 3',4'(2-hydroxy methyl, 1",4"-dioxino) flavone (4g) were found to exhibit a significant activity comparable to standard drug silymarin (silybon-70). Other compounds also exhibited good activity. The structure activity relationship (SAR) was also studied, and where the flavonoid analogues containing a hydroxy methyl group at position-2" in the dioxane ring exhibited superior antihepatotoxic activity in comparison to coumarin derivatives. 相似文献
50.
Najib NM Idkaidek N Adel A Admour I Astigarraga RE Nucci GD Alam SM Dham R Qumaruzaman 《Biopharmaceutics & drug disposition》2003,24(5):183-189
The pharmacokinetics of two brands of simvastatin 40 mg tablets were compared in 24 healthy human volunteers after a single oral dose in a randomized cross-over study, conducted at IPRC, Amman, Jordan. Reference (Zocor, MSD, Netherlands) and test (Simvast, Julphar, UAE) products were administered to fasted volunteers; blood samples were collected at specified time intervals, plasma separated and analyzed for simvastatin and its active metabolite (beta-hydoxy acid) using a validated LC-MS/MS method at Cartesius Analytical Unit, Institute of Biomedical Sciences - USP, Sao Paulo, Brazil. The pharmacokinetic parameters AUC(0-t), AUC(0-variant), C(MAX), T(MAX), T(1/2) and elimination rate constant were determined from plasma concentration-time profile for both formulations and were compared statistically to evaluate bioequivalence between the two brands, using the statistical modules recommended by FDA. The analysis of variance (ANOVA) did not show any significant difference between the two formulations and 90% confidence intervals fell within the acceptable range for bioequivalence. Based on these statistical inferences it was concluded that the two brands exhibited comparable pharmacokinetic profiles and that Julphar's Simvast is bioequivalent to Zocor of MSD, Netherlands. 相似文献