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41.
Integration of behavioral health and medicine has gained increased support recently within the new field of complementary medicine. Providers from both disciplines are acknowledging the mind-body connection and recognizing the value of treating the whole patient through working within an integrative delivery model. This paper describes two treatment programs which were developed using the principles of the mind-body connection and implemented within an integrative setting at a large HMO. The results of research studies are presented and discussed to demonstrate the efficacy of these programs.  相似文献   
42.
Imaging the 5-HT(1A) receptors with PET: WAY-100635 and analogues   总被引:1,自引:0,他引:1  
This paper summarizes our work on WAY-100635 and analogues, labeled either with carbon-11 or fluorine-18, as potential radioligands for the 5-hydroxytryptamine(1A) (5-HT(1A)) neuroreceptors. Other facets of our work include: (1) human studies with [O-methyl-(11)C]WAY-100634, the major radioactive metabolite of [O-methyl-(11)C]WAY-100635, and with [(11)C]CPC 222; (2) use of a human liver metabolism model to screen in vitro potential metabolic problems in humans; (3) modification of the "dry method" to prepare [carbonyl-(11)C]WAY-100635; and (4) validation studies in humans with [carbonyl-(11)C]WAY-100635.  相似文献   
43.
Prochloraz is a commonly used fungicide that has shown multiple mechanisms of action in vitro. It antagonizes the androgen and the estrogen receptors, agonizes the Ah receptor, and inhibits aromatase activity. In vivo prochloraz acts antiandrogenically in the Hershberger assay by reducing weights of reproductive organs, affecting androgen-regulated gene expressions, and increasing luteinizing hormone (LH) levels. The purpose of this study was to investigate reproductive toxic effects after exposure during gestation and lactation to prochloraz alone and a mixture of five pesticides (deltamethrin, methiocarb, prochloraz, simazine, and tribenuron-methyl). Prochloraz (30 mg/kg/day) or the mixture (20 mg/kg/day) was dosed to pregnant Wistar dams from gestational day (GD) 7 until postnatal day (PND) 16. Some dams were taken for cesarean section at GD 21, and others were allowed to give birth. Results showed that prochloraz and the mixture significantly reduced plasma and testicular testosterone levels in GD 21 male fetuses, whereas testicular progesterone was increased. Gestational length was increased by prochloraz. Chemical analysis of the rat breast milk showed that prochloraz was transferred to the milk. In males a significant increase of nipple retention was found, and the bulbourethral gland weight was decreased, whereas other reproductive organs were unaffected. In addition cytochrome P450 (CYP)1A activities in livers were induced by prochloraz, possibly as a result of Ah receptor activation. Behavioral studies showed that the activity level and sweet preference of adult males were significantly increased. Overall these results strongly indicate that prochloraz feminizes the male offspring after perinatal exposure, and that these effects are due, at least in part, to diminished fetal steroidogenesis.  相似文献   
44.
The aim of the study was to compare neuromuscular activation in the gluteus maximus, the biceps femoris and the erector spinae from the Romanian deadlift, the 45-degree Roman chair back extension and the seated machine back extension. Fifteen resistance-trained females performed three repetitions with 6-RM loading in all exercises in a randomized and counterbalanced order. The activation in the whole movement as well as its lower and upper parts were analyzed. The results showed that the Romanian deadlift and the Roman chair back extension activated the gluteus maximus more than the seated machine back extension (94-140%, p < 0.01). For the biceps femoris the Roman chair elicited higher activation compared to both the Romanian deadlift and the seated machine back extension (71-174%). Further, the Romanian deadlift activated the biceps femoris more compared to the seated machine back extension (61%, p < 0.01). The analyses of the different parts of the movement showed that the Roman chair produced higher levels of activation in the upper part for both the gluteus maximus and the biceps femoris, compared to the other exercises. There were no differences in activation of the erector spinae between the three exercises (p = 1.00). In conclusion, both the Roman deadlift and the Roman chair back extension would be preferable to the seated machine back extension in regards to gluteus maximus activation. The Roman chair was superior in activating the biceps femoris compared to the two other exercises. All three exercises are appropriate selections for activating the lower back muscles. For overall lower limb activation, the Roman chair was the best exercise.Key points
  • In general, the Roman chair back extension lead to superior muscle activation compared to the Romanian deadlift and the seated machine back extension
  • The seated machine back extension showed the lowest gluteus and hamstring activation
  • All three exercises are appropriate selections for activating the lower back muscles
  • The differences in muscle activation are most likely caused by biomechanical differences.
Key words: Gluteus maximus, biceps femoris, erector spinae, muscle activation  相似文献   
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Subcutaneous tissue is part of a bodywide network of “loose” connective tissue including interstitial connective tissues separating muscles and surrounding all nerves and blood vessels. Despite its ubiquitous presence in the body and its potential importance in a variety of therapies utilizing mechanical stretch, as well as normal movement and exercise, very little is known about loose connective tissue's biomechanical behavior. This study aimed to determine elastic and viscoelastic mechanical properties of ex-vivo rat subcutaneous tissue in uniaxial tension with incremental stress relaxation experiments. The elastic response of the tissue was linear, with instantaneous and equilibrium tensile moduli of 4.77 kPa and 2.75 kPa, respectively. Using a 5 parameter Maxwell solid model, material parameters μ1 = 0.95 ± 0.24 Ns/m and μ2 = 8.49 ± 2.42 Ns/m defined coefficients of viscosity related to time constants τ1M = 3.83 ± 0.15 sec and τ2M = 30.15 ± 3.16 sec, respectively. Using a continuous relaxation function, parameters C = 0.25 ± 0.12, τ1C = 1.86 ± 0.34 sec, and τ2C = 110.40 ± 25.59 sec defined the magnitude and frequency limits of the relaxation spectrum. This study provides baseline information for the stress-strain behaviors of subcutaneous connective tissue. Our results underscore the differences in mechanical behaviors between loose and high-load bearing connective tissues and suggest that loose connective tissues may function to transmit mechanical signals to and from the abundant fibroblasts, immune, vascular, and neural cells present within these tissues.  相似文献   
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Endothelial cell migration induced in response to vascular endothelial growth factor (VEGF) is a crucial step of angiogenesis and it depends on the activation of the p38 MAP-kinase pathway downstream of VEGFR2. In this study, we investigated the role of microRNAs (miRNAs) in regulating these processes. We found that the VEGF-induced p38 activation and cell migration are modulated by overexpression of Argonaute 2, a key protein in the functioning of miRNAs. Thereafter, we found that miR-20a expression is increased by VEGF and that its ectopic expression inhibits VEGF-induced actin remodeling and cell migration. Moreover, the expression of miR-20a impairs the formation of branched capillaries in a tissue-engineered model of angiogenesis. In addition, the lentivirus-mediated expression of miR-20a precursor (pmiR-20a) is associated with a decrease in the VEGF-induced activation of p38. In contrast, these processes are increased by inhibiting miR-20a with a specific antagomir. Interestingly, miR-20a does not modulate VEGFR2 or p38 protein expression level. miR-20a does not affect either the expression of other known actors of the p38 MAP kinase pathway except MKK3. Indeed, by using quantitative PCR and Western Blot analysis, we found that pmiR-20a decreases the expression of MKK3 and we obtained evidence indicating that miR-20a specifically binds to the 3′UTR region of MKK3 mRNA. In accordance, the VEGF-induced activation of p38 and cell migration are impaired when the MKK3 expression is knocked down by siRNA. We conclude that miR-20a acts in a feedback loop to repress the expression of MKK3 and to negatively regulate the p38 pathway-mediated VEGF-induced endothelial cell migration and angiogenesis.  相似文献   
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