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991.
Bioassay-guided fractionation of a CHCl (3) extract prepared from the Mexican medicinal plant Hyptis pectinata led to the isolation of four pyrones, pectinolides A-C ( 1-3) and H ( 4). Activity was tracked using cultured KB cells. Multidrug-resistant strains of Staphylococcus aureus were sensitive to pectinolide H ( 4; KB > 20 microg/mL) in the concentration range of 32-64 microg/mL. The absolute stereochemistry of this new compound was established as 5 S-[(4 S-acetyloxy)-(1 S-hydroxy)-2 Z-octenyl]-2(5 H)-furanone on the basis of spectral, chiroptical data and chemical correlation with pectinolide A ( 1). Mosher ester derivatives were used with pectinolide B ( 2) for confirmation of the 3'-( S) absolute stereochemistry on the side chain chiral center of pectinolides A-C. 相似文献
992.
Barnes J Anderson LA Gibbons S Phillipson JD 《The Journal of pharmacy and pharmacology》2005,57(8):929-954
This paper reviews the chemistry, pharmacology and clinical properties of Echinacea species used medicinally. The Echinacea species Echinacea angustifolia, Echinacea pallida and Echinacea purpurea have a long history of medicinal use for a variety of conditions, particularly infections, and today echinacea products are among the best-selling herbal preparations in several developed countries. Modern interest in echinacea is focused on its immunomodulatory effects, particularly in the prevention and treatment of upper respiratory tract infections. The chemistry of Echinacea species is well documented, and several groups of constituents, including alkamides and caffeic acid derivatives, are considered important for activity. There are, however, differences in the constituent profile of the three species. Commercial echinacea samples and marketed echinacea products may contain one or more of the three species, and analysis of samples of raw material and products has shown that some do not meet recognized standards for pharmaceutical quality. Evidence from preclinical studies supports some of the traditional and modern uses for echinacea, particularly the reputed immunostimulant (or immunomodulatory) properties. Several, but not all, clinical trials of echinacea preparations have reported effects superior to those of placebo in the prevention and treatment of upper respiratory tract infections. However, evidence of efficacy is not definitive as studies have included different patient groups and tested various different preparations and dosage regimens of echinacea. On the basis of the available limited safety data, echinacea appears to be well tolerated. However, further investigation and surveillance are required to establish the safety profiles of different echinacea preparations. Safety issues include the possibility of allergic reactions, the use of echinacea by patients with autoimmune diseases and the potential for echinacea preparations to interact with conventional medicines. 相似文献
993.
Antman EM Anbe DT Armstrong PW Bates ER Green LA Hand M Hochman JS Krumholz HM Kushner FG Lamas GA Mullany CJ Ornato JP Pearle DL Sloan MA Smith SC Alpert JS Anderson JL Faxon DP Fuster V Gibbons RJ Gregoratos G Halperin JL Hiratzka LF Hunt SA Jacobs AK;American College of Cardiology/American Heart Association Task Force on Practice Guidelines 《Circulation》2004,110(5):588-636
994.
Antman EM Anbe DT Armstrong PW Bates ER Green LA Hand M Hochman JS Krumholz HM Kushner FG Lamas GA Mullany CJ Ornato JP Pearle DL Sloan MA Smith SC Alpert JS Anderson JL Faxon DP Fuster V Gibbons RJ Gregoratos G Halperin JL Hiratzka LF Hunt SA Jacobs AK;American College of Cardiology;American Heart Association Task Force on Practice Guidelines;Canadian Cardiovascular Society 《Circulation》2004,110(9):e82-292
995.
Wong BC Gillman NC Oehninger S Gibbons WE Stadtmauer LA 《American journal of obstetrics and gynecology》2004,191(2):597-606; discussion 606-7
OBJECTIVE: The purpose of this study was to investigate the effect of endometriomas on clinical pregnancy rates of in vitro fertilization-embryo transfer. STUDY DESIGN: Infertile patients with endometriosis who underwent in vitro fertilization-embryo transfer were divided into group 1 patients who had a history of ovarian endometriomas and group 2 patients who did not. The patients in group 1 were further divided into group 1A who had their endometriomas removed by laparoscopic ovarian cystectomy before the start of in vitro fertilization-embryo transfer and group 1B who underwent in vitro fertilization-embryo transfer with the presence of endometriomas. The clinical pregnancy rates of these groups were compared. RESULTS: Clinical pregnancy rates per transfer were similar in group 1 and group 2 (40% vs 47%; P =.38) and similar in patients in group 1A and group 1B (47% vs 34%; P =.28), although the direction was toward improved pregnancy rates in the groups of patients without endometriomas present at the time of in vitro fertilization stimulation. When patients >39 years of age were excluded, the overall pregnancy rate was higher in those patients who had no current endometriomas than in those patients who had endometriomas present at the time of stimulation (65% vs 39%; P =.05). For patients with unilateral endometriomas, similar numbers of mature oocytes were aspirated between the affected and unaffected ovaries. CONCLUSION: Although the history of endometriomas does not appear to affect in vitro fertilization-embryo transfer outcomes adversely, there may be a benefit in the removal of endometriomas before in vitro fertilization. 相似文献
996.
Gueven N Becherel OJ Kijas AW Chen P Howe O Rudolph JH Gatti R Date H Onodera O Taucher-Scholz G Lavin MF 《Human molecular genetics》2004,13(10):1081-1093
Ataxia-oculomotor apraxia (AOA1) is a neurological disorder with symptoms that overlap those of ataxia-telangiectasia, a syndrome characterized by abnormal responses to double-strand DNA breaks and genome instability. The gene mutated in AOA1, APTX, is predicted to code for a protein called aprataxin that contains domains of homology with proteins involved in DNA damage signalling and repair. We demonstrate that aprataxin is a nuclear protein, present in both the nucleoplasm and the nucleolus. Mutations in the APTX gene destabilize the aprataxin protein, and fusion constructs of enhanced green fluorescent protein and aprataxin, representing deletions of putative functional domains, generate highly unstable products. Cells from AOA1 patients are characterized by enhanced sensitivity to agents that cause single-strand breaks in DNA but there is no evidence for a gross defect in single-strand break repair. Sensitivity to hydrogen peroxide and the resulting genome instability are corrected by transfection with full-length aprataxin cDNA. We also demonstrate that aprataxin interacts with the repair proteins XRCC1, PARP-1 and p53 and that it co-localizes with XRCC1 along charged particle tracks on chromatin. These results demonstrate that aprataxin influences the cellular response to genotoxic stress very likely by its capacity to interact with a number of proteins involved in DNA repair. 相似文献
997.
Fryer G Morris T Gibbons P 《Journal of manipulative and physiological therapeutics》2004,27(4):267-274
BACKGROUND: One of the diagnostic characteristics of the manipulable spinal lesion--a musculoskeletal disturbance detected by manual palpation and corrected with manipulation--is said to be altered segmental tissue texture. Various manual therapy authors have speculated on the possible nature of this tissue change, with some authors hypothesizing that it represents deep segmental muscle overactivity. OBJECTIVES: To review the literature relating to the detection and nature of altered paraspinal tissue texture, proposed explanations for altered tissue texture, evidence for the plausibility of paraspinal muscle spasm, and evidence of muscle dysfunction associated with low back pain (LBP). DATA SOURCE: MEDLINE and CINAHL databases were searched using various combinations of the keywords paraspinal, muscle, palpation, EMG, spine, low back pain, pain, myofascial, hardness, manipulation, reliability, and somatic dysfunction, along with searching the bibliographies of selected articles and textbooks. DATA EXTRACTION: All relevant data were used. RESULTS: Little direct evidence exists for the nature of abnormal paraspinal tissue texture detected by palpation. Palpation for tenderness is more reliable than palpation for tissue texture change. Indirect evidence from animal studies and experimental muscle inflammation support the plausibility of protective paraspinal muscle contraction. Increased paraspinal electromyographic (EMG) activity observed in subjects with LBP appears to be a result of voluntary and nonvoluntary changes in motor control, modified by psychophysiological responses to perceived stress rather than a simple protective reflex. CONCLUSION: Although little direct evidence exists of the nature of clinically detected paraspinal tissue texture change, the concept of reactive muscle contraction appears plausible. Increased paraspinal EMG activity associated with LBP does not appear to be mediated by a simple protective reflex. 相似文献
998.
Gibbons D 《Professional nurse (London, England)》2004,19(11):39-40, 42
The role of spirometry in the assessment of lung function and the diagnosis of lung disease should not be underestimated. Accurate measurements require a proficient operator trained in the use of the equipment and in supporting patients throughout. 相似文献
999.
1000.
The role of the popliteofibular ligament and the tendon of popliteus in providing stability in the human knee 总被引:3,自引:0,他引:3
Pasque C Noyes FR Gibbons M Levy M Grood E 《The Journal of bone and joint surgery. British volume》2003,85(2):292-298
Techniques for the selective cutting of ligaments in cadaver knees defined the static contributions of the posterolateral structures to external rotation, varus rotation and posterior tibial translation from 0 degrees to 120 degrees of flexion under defined loading conditions. Sectioning of the popliteofibular ligament (PFL) (group 1) produced no significant changes in the limits of the knee movement studied. Sectioning of the PFL and the popliteus tendon (femoral attachment, group 2) produced an increase of only 5 degrees to 6 degrees in external rotation from flexion of 30 degrees to 120 degrees (p < 0.001). Even when other ligaments were sectioned first (group 3), the maximum effect of the PFL was negligible. Our findings show that the popliteus muscle-tendon-ligament complex, lateral collateral ligament, and posterolateral capsular structures function as a unit. No individual structure alone is the primary restraint for the movements studied. Operative reconstruction should address all of the posterolateral structures, since restoration of only a portion may result in residual instability. 相似文献