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排序方式: 共有1744条查询结果,搜索用时 15 毫秒
101.
Cherkin DC Deyo RA Sherman KJ Hart LG Street JH Hrbek A Davis RB Cramer E Milliman B Booker J Mootz R Barassi J Kahn JR Kaptchuk TJ Eisenberg DM 《The Journal of the American Board of Family Practice / American Board of Family Practice》2002,15(6):463-472
BACKGROUND: Despite growing popularity of complementary and alternative medical (CAM) therapies, little is known about the patients seen by CAM practitioners. Our objective was to describe the patients and problems seen by CAM practitioners. METHODS: We collected data on 20 consecutive visits to randomly sampled licensed acupuncturists, chiropractors, massage therapists, and naturopathic physicians practicing in Arizona, Connecticut, Massachusetts, and Washington. Data were collected on patient demographics, smoking status, referral source, reasons for visit, concurrent medical care, payment source, and visit duration. Comparative data for conventional physicians were drawn from the National Ambulatory Medical Care Survey. RESULTS: In each profession, at least 99 practitioners collected data on more than 1,800 visits. More than 80% of visits to CAM providers were by young and middle-aged adults, and roughly two thirds were by women. Children comprised 10% of visits to naturopathic physicians but only 1% to 4% of all visits to other CAM providers. At least two thirds of visits resulted from self-referrals, and only 4% to 12% of visits were from conventional physician referrals. Chiropractors and massage therapists primarily saw musculoskeletal problems, while acupuncturists and naturopathic physicians saw a broader range of conditions. Visits to acupuncturists and massage therapists lasted about 60 minutes compared with 40 minutes for naturopathic physicians and less than 20 minutes for chiropractors. Most visits to chiropractors and naturopathic physicians, but less than one third of visits to acupuncturists and massage therapists, were covered by insurance. CONCLUSIONS: This information will help inform discussions of the roles CAM practitioners will play in the health care system of the future. 相似文献
102.
Liver transplantation is an accepted modality of treatment in some patients with inborn errors of metabolism. We present a child with methylmalonic acidaemia who had successful liver transplantation. The pathophysiology, medical and anaesthetic managements are discussed. 相似文献
103.
Virdis R Sigorini M Laiolo A Lorenzetti E Street ME Villani AR Donadio A Pisani F Terzi C Garavelli L 《Journal of pediatric endocrinology & metabolism : JPEM》2000,13(Z1):841-844
Since neurofibromatosis type 1 (NF1) is a well known cause of precocious puberty (PP), we reviewed 412 NF1 pediatric patients to evaluate the prevalence of PP, the association with optic pathway tumors (OPT), and other clinical, auxological and hormonal data. Thirty-one of 412 patients had OPT (7.5%), 10/412 PP (2.4%), and in seven of these PP was associated with OPT (7/31, 22.6%). OPT in patients with PP involved the chiasm in four patients, and the optic nerves alone in three patients. The age at the onset of puberty (or better at diagnosis) ranged from 5.2 to 7.5 yr in girls (n=6) and from 7.9 to 8.9 yr in boys (n=4). LHRH agonist therapy was used in only three children because in the others the predicted height at diagnosis was good, treatment was refused or the patients were referred to us too late. The three treated patients attained a final height within the familial range. In the untreated patients the progression of puberty was not too rapid and final height was slightly below the genetic target in four patients; however, three patients had a final height markedly below the familial range. In conclusion, the prevalence of PP is increased in children with NF1, and frequently but not exclusively is associated with OPT. Moreover, sexual precocity does not seem to be necessarily bound to chiasmatic OPT. Treatment seems to be useful in the children with younger age at the onset of puberty or with a progressive decline in predicted final height. 相似文献
104.
105.
Phorbol ester-sensitive EL4 murine thymoma cells respond to phorbol 12-
myristate 13-acetate with activation of ERK mitogen-activated protein
kinases, synthesis of interleukin-2, and death, whereas phorbol ester-
resistant variants of this cell line do not exhibit these responses.
Additional aspects of the resistant phenotype were examined, using a
newly-established resistant cell line. Phorbol ester induced morphological
changes, ERK activation, calcium-dependent activation of the c-Jun
N-terminal kinase (JNK), interleukin-2 synthesis, and growth inhibition in
sensitive but not resistant cells. A series of protein kinase C activators
caused membrane translocation of protein kinase C's (PKCs) alpha, eta, and
theta in both cell lines. While PKC eta was expressed at higher levels in
sensitive than in resistant cells, overexpression of PKC eta did not
restore phorbol ester-induced ERK activation to resistant cells. In
sensitive cells, PKC activators had similar effects on cell viability and
ERK activation, but differed in their abilities to induce JNK activation
and interleukin-2 synthesis. PD 098059, an inhibitor of the mitogen
activated protein (MAP)/ERK kinase kinase MEK, partially inhibited ERK
activation and completely blocked phorbol ester-induced cell death in
sensitive cells. Thus MEK and/or ERK activation, but not JNK activation or
interleukin-2 synthesis, appears to be required for phorbol ester-induced
toxicity. Alterations in phorbol ester response pathways, rather than
altered expression of PKC isoforms, appear to confer phorbol ester
resistance to EL4 cells.
相似文献
106.
The present report describes psychobiological studies of behavior around the time of birth. An adaptive, ecological perspective is presented in which stimulation of the fetus and newborn is purported to instigate adaptive postpartum behavior. Studies describing the perinatal sensory environment are reviewed, with a consideration of emergent sensory function of the fetus. It is asserted that afferent input associated with parturition perturbs the fetus and neonate, producing a general arousal state that facilitates breathing, suckling, and early learning. The view developed herein is that perinatal sensory input induces and canalizes the newborn's behavior, thereby regulating adaptive postpartum function. Deviations in afferent input may alter ontogenetic trajectories and compromise developmental outcome by reducing availability of conditions necessary for adequate postpartum adaptation. 相似文献
107.
The E7 oncoprotein of human papillomavirus 16 functions as a tumor-specific antigen in transformed epithelial cells of the uterine cervix to which immunotherapeutic strategies aimed at CTL induction may be directed. We previously have shown in mice transgenic for the E7 gene driven off an epithelial specific (keratin-14) promoter, that expression of E7 protein in peripheral epithelium is sufficient to tolerize E7-directed CTL precursors (pCTL; Doan et al, J. Virol., 73: 6166-1670, 1999). Here we show that E7 is presented to T cells for tolerization by cells of bone marrow origin ("cross-tolerization"). We demonstrate that tolerization of E7-directed pCTLs occurs within 2 weeks of exposure to E7 in epithelium. It is maintained in the near absence of CD4+ cells and in the absence of the thymus, and is independent of a coexisting E7-directed Th2-type antibody response. Tolerance was broken by immunization with E7 CTL epitope-pulsed dendritic cells. These findings have implications for immunotherapy of patients with human papillomavirus 16-associated cervical carcinoma, whose immune systems may have experienced long-term exposure to E7-expressing epithelial cells. 相似文献
108.
Comparison of the vasoconstrictor effects of the selective 5-HT1D-receptor agonist L-775,606 with the mixed 5-HT1B/1D-receptor agonist sumatriptan and 5-HT in human isolated coronary artery
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Longmore J Maguire JJ MacLeod A Street L Schofield WN Hill RG 《British journal of clinical pharmacology》2000,49(2):126-131
AIMS: Vasoconstriction in human coronary artery can be mediated via activation of both 5-HT2 and 5-HT1B-receptors. Coronary vasoconstriction is a rare, but potential adverse effect of the antimigraine drug sumatriptan. In order to investigate the receptor population involved we compared the vasoconstrictor effects of sumatriptan (a mixed 5-HT1B/1D-receptor agonist) with those of L-775, 606 (a selective 5-HT1D-receptor agonist) and 5-HT (the endogenous ligand) in human isolated coronary arteries. METHODS: Coronary arteries were obtained from human hearts removed prior to transplant surgery. Several endothelium denuded ring segments (4 mm in length) were obtained from each artery and mounted for isometric tension recording. Each segment was first exposed to 45 mm KCl and then to 5-HT (1 nm-100 microm ). Concentration-effect curves to L-775,606 (1-(3-(5-(1,2, 4-triazol-4-yl)-1H-indol-3-yl)propyl)-4-(2-(3-fluorophenyl)ethyl)p ipe razine) and sumatriptan were then performed in a consecutive and random manner. The response to repeated application of 5-HT was obtained in separate segments. RESULTS: Twenty-five segments from seven different coronary arteries were studied. Concentration-effect curves were fitted to the data using nonlinear regression analysis. The maximum contraction for L-775,606 was significantly less than that for sumatriptan with Emax values (% relative to 45 mm KCl=100%) of 30.1+/-4.22 and 41.5+/-2.7, respectively. L-775,606 was significantly (30-fold) less potent than sumatriptan in causing contraction compared with sumatriptan (EC50 values were 6.0 microm and 0.2 microm, respectively). For comparison the Emax value for 5-HT was 77.2% and the EC50 value was 0.2 microm. CONCLUSIONS: The selective 5-HT1D-receptor agonist L-775,606 has less propensity towards vasoconstriction in human isolated coronary artery (endothelium-denuded) than was mixed 5-HT1B/1D-receptor agonist sumatriptan. The contractions produced were at concentrations where L-775,606 would be expected to occupy 5-HT1B-receptors. 相似文献
109.
110.
Technological advances in cross-country ski equipment. 总被引:1,自引:0,他引:1
G M Street 《Medicine and science in sports and exercise》1992,24(9):1048-1054
Nordic skiing has a long history dating back to at least 2500 B.C. It is not surprising then that skiing equipment has undergone many changes. Today's skis, poles, and boots use the latest in space-age synthetics including carbon and Kevlar fibers, which has resulted in an unprecedented advance in ski equipment technology, producing ultralight yet strong equipment. These changes have played an important role in bringing about an improvement in racing performance with today's skiers being able to ski a course in half the amount of time that it would have taken just 60 yr ago. Estimates indicate the change in mass of racing equipment accounts for a relatively small amount (12%) of the improvement in race performance with changes in the functional characteristics of equipment, track preparation, and training practices being responsible for the remaining 88%. In addition to improvements in ski equipment, advances are being made in developing laboratory equipment used to assess an athlete's upper body power and endurance capacities. Lab testing with an arm ergometer showed its utility when it exposed a glaring deficiency in upper body power among a group of U.S. developmental skiers. Further improvement in ski equipment and lab testing tools are expected in the future as the worldwide technological revolution continues and Olympic Teams and sports science groups continue to work cooperatively. 相似文献