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851.
Vasorelaxant effects of ethyl cinnamate isolated from Kaempferia galanga on smooth muscles of the rat aorta 总被引:1,自引:0,他引:1
From the rhizomes of Kaempferia galanga, ethyl cinnamate (EC) was isolated and its vasorelaxant effect was examined on the rat aorta. EC inhibited the tonic contractions induced by high K+ and phenylephrine (PE) in a concentration-dependent manner, with respective IC50 values of 0.30 +/- 0.05 mM and 0.38 +/- 0.04 mM. The relaxant effect against PE-induced contractions was greater in the presence of endothelium. Pre-treatment of the aorta with methylene blue and indomethacin significantly reduced the relaxant effect. These results suggest that the inhibitory effects of EC may involve inhibition of Ca2+ influx into vascular cells and release of nitric oxide (NO) and prostacyclin from the endothelial cells. Thus, the vasorelaxant effect of EC mediated through multiple pathways may explain the traditional use of the parent plant in treating hypertension. 相似文献
852.
L Esther de Graaf Sylvia AH Gerhards Silvia MAA Evers Arnoud Arntz Heleen Riper Johan L Severens Guy Widdershoven Job FM Metsemakers Marcus JH Huibers 《BMC public health》2008,8(1):224
Background
Major depression is a common mental health problem in the general population, associated with a substantial impact on quality of life and societal costs. However, many depressed patients in primary care do not receive the care they need. Reason for this is that pharmacotherapy is only effective in severely depressed patients and psychological treatments in primary care are scarce and costly. A more feasible treatment in primary care might be computerised cognitive behavioural therapy. This can be a self-help computer program based on the principles of cognitive behavioural therapy. Although previous studies suggest that computerised cognitive behavioural therapy is effective, more research is necessary. Therefore, the objective of the current study is to evaluate the (cost-) effectiveness of online computerised cognitive behavioural therapy for depression in primary care. 相似文献853.
Furqan Ahmed Muhammad Zain-ul-abdein Iftikhar Ahmed Channa Muhammad Kamran Yaseen Sadaf Jamal Gilani Muhammad Atif Makhdoom Muhammad Mansoor Usman Shahzad May Nasser bin Jumah 《Materials》2022,15(15)
Commercially pure titanium (Ti) is widely used in bio-implants due to its high corrosion resistance. However, Ti exhibits marginally low mechanical and tribological properties, which limit its applications in some orthopedic implants. In this work, the Ti samples were subjected to ultrasonic surface mechanical attrition treatment (SMAT) for various durations to improve their surface properties such as hardness, strength and surface energy. SMAT-induced grain refinement was analyzed using optical, scanning electron and atomic force microscopy techniques. A Vickers hardness test was performed to determine the through-thickness hardness. Mechanical testing was carried out to measure the yield strength, ultimate tensile strength and ductility of the specimens. Corrosion tests were performed on a Gamry Potentiostat. The surface energy of SMAT-modified samples was calculated using the Owens–Wendt method. It was observed that SMAT reduced the average grain size from 50 μm to as low as 100 nm. The grain refinement and the corresponding grain boundary density led to a significant improvement in mechanical properties and biocompatibility in terms of increased hardness, yield and tensile strengths, surface energy, corrosion rate and hydrophilicity. 相似文献
854.
Assessing and addressing cognitive impairment in bipolar disorder: the International Society for Bipolar Disorders Targeting Cognition Task Force recommendations for clinicians 下载免费PDF全文
855.
856.
Saeed SA Gilani AH Rasheed H Bhatti FN Atiq M Qureshi A Jafary R Connor JD 《Research communications in molecular pathology and pharmacology》2002,111(1-4):69-76
Methotrexate (MTX) in low doses is commonly used to treat rheumatoid arthritis (RA). At least 36 deaths have been attributed to bone marrow cytotoxicity associated with low dose MTX. The goal was to determine if plasma from arthritis patients taking low dose MTX induces platelet aggregation in platelet rich plasma from healthy volunteers. Plasma from patients on MTX alone caused a 3-fold increase in aggregation vs plasma from controls (P<0.05). Plasma from patients not taking MTX or taking MTX with diclofenac caused aggregation to a lesser extent. Diclofenac, along with several others NSAIDs and cyclooxygenase inhibitors, depressed aggregation produced by arachidonic acid in platelet rich plasma from healthy volunteers. A precise mechanism for amplification of aggregation by MTX plasma and its relationship to MTX toxicity remains unknown. However, a serum factor may be produced by MTX that modulates the activity of cyclooxygenase, thereby influencing aggregation. 相似文献
857.
Gilani NP 《Journal of adolescence》1999,22(6):853-865
Research on the mother-daughter relationship during adolescence is mostly conducted in Western and European cultures where individualism is stressed. To examine ethnic/cultural differences and similarities in this relationship, 80 dyads of British (white) and Pakistani mothers and their adolescent daughters were studied. On the basis of the theories of cultural variability dimension and conflict face negotiation, it was hypothesized that mothers and daughters from the two cultures would use different styles of handling disagreements/conflicts. That is, Pakistani mothers and daughters would use an avoiding style, whereas British mothers and daughters would use either a dominating or compromising style, to a greater degree. It was also argued that Pakistani daughters and mothers will express more intimacy and relational harmony, will exhibit greater connectedness and mutuality and demonstrate lesser individuality and self-assertion compared to their British counterparts. However, it appeared that both the groups used an avoiding style equally, although the British group used a dominating style more than Pakistani group. As hypothesized, Pakistani mothers and daughters expressed more intimacy, relational harmony, connectedness and mutuality and lesser individuality than British mothers and daughters. 相似文献
858.
Huntingtin-associated protein 1 (HAP1) binds to a Trio-like polypeptide, with a rac1 guanine nucleotide exchange factor domain 总被引:1,自引:4,他引:1
Colomer V; Engelender S; Sharp AH; Duan K; Cooper JK; Lanahan A; Lyford G; Worley P; Ross CA 《Human molecular genetics》1997,6(9):1519-1525
Huntington's disease (HD) occurs when the widely expressed protein
huntingtin contains an expanded glutamine repeat. The selective
degeneration and neuronal morphologic abnormalities of HD may involve
interactions with proteins that bind to huntingtin, such as HAP1. The
biological significance of this interaction is unclear because neither HAP1
nor huntingtin have significant homology to known proteins. Therefore, we
sought to identify HAP1-binding proteins. Using the yeast two-hybrid
system, we isolated a rat cDNA encoding part of a protein that interacts
with HAP1, and we confirmed the specificity of this interaction using an in
vitro protein-binding assay. We called the protein Duo because it is
closely related to the human protein Trio but is shorter. Northern blot
analysis indicates brain-specific expression of Duo. Human Duo contains a
guanine nucleotide exchange factor (GEF) domain that is likely to be
rac1-specific, a pleckstrin homology (PH) domain and spectrin-like repeat
units. These data support the hypothesis that huntingtin is involved in
vesicle trafficking and cytoskeletal functions, and raise the possibility
of a role for huntingtin in the regulation of a ras-related signaling
pathway.
相似文献
859.
Davies JL; Cucca F; Goy JV; Atta ZA; Merriman ME; Wilson A; Barnett AH; Bain SC; Todd JA 《Human molecular genetics》1996,5(7):1071-1074
Linkage analysis of type 1 diabetes sib pair families (n = 334) has
suggested two separate regions of human chromosome 6q are linked to disease
(designated IDDM5 and IDDM8). To test if these are false positive results,
all available sib pair families (n = 429) were typed using a 92%
informative map of chromosome 6q and multipoint analysis. The two regions
still showed positive evidence of linkage, most notably the proterminal
region, 6q27, corresponding to IDDM8 (MLS = 2.57, p = 0.0006; lambda s =
1.17). In addition, some evidence of transmission disequilibrium was seen
with marker a046xa9 (IDDM5).
相似文献
860.
The applicability of the flow cytometric sperm chromatin structure assay in epidemiological studies. Asclepios 总被引:2,自引:2,他引:2
Spano M; Kolstad AH; Larsen SB; Cordelli E; Leter G; Giwercman A; Bonde JP 《Human reproduction (Oxford, England)》1998,13(9):2495-2505
The impact of demographic, lifestyle, and seminal factors on the sperm
chromatin structure assay (SCSA) parameters was evaluated in a population
of 277 healthy Danish men. This cohort was established within the framework
of a European Concerted Action on occupational hazards to male reproductive
capability in order to examine the possible reproductive effects of
exposure to styrene or pesticides. The SCSA measures the susceptibility of
sperm DNA to in-situ acid-induced denaturation, by multiparameter flow
cytometric analysis after staining with the DNA-specific fluorescent dye
acridine orange. The green versus red bivariate cytogram patterns were
quite variable among donors, showing a wide heterogeneity of sperm DNA
denaturability. Nevertheless, in those cases where we had the possibility
to measure two semen samples from the same donor, the cytogram pattern
remained stable over time (0.64 < r < 0.78). Analysis of variance
demonstrated that the SCSA results can be influenced by the age of the
donor (P < 0.0001), smoking habits (P < 0.05), the presence of
leukocytes and immature germ forms in the ejaculate (P < 0.0001), and
the duration of sexual abstinence (P < 0.0001). Furthermore, the
relationship between the SCSA data and sperm concentration, morphology, and
vitality was weak (-0.22 < r < - 0.46). Therefore, the SCSA provides
independent and complementary measurements of semen quality and is thus a
useful tool for epidemiological studies, but the effects of some
confounders should be accounted for in the survey design and analysis.
相似文献