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991.
992.
WM Tsui R Colombari BC Portmann F Bonetti SN Thung LD Ferrell Y Nakanuma DC Snover P Bioulac-Sage AP Dhillon 《Canadian Metallurgical Quarterly》1999,23(1):34-48
Posttraumatic headache can be a very difficult syndrome to manage, especially if chronic. As with most other types of headache, medications are the primary treatment modality, although there is very limited evidence-based data to support any given approach. A number of physical interventions also are available to be used in conjunction with medication, particularly for headaches with a musculoskeletal component. This article will review the general principles of pharmacological treatment for headache and the physical approach to treatment of headaches and head and facial pain. The major categories of medications commonly used for treatment of many varieties of headache will be discussed. In addition, the problems encountered in diagnosing and treating chronic daily headache and analgesic rebound headache are addressed. The approach to treatment of such syndromes as myofascial pain, cervico-zygapophyseal joint pain, neuritic pain, and craniocervical somatic pain are outlined. 相似文献
993.
Maria I Gallão Ícaro GP Vieira Francisca NP Mendes Alex SN de Souza Edy S de Brito 《Journal of the science of food and agriculture》2007,87(11):2012-2018
The seeds of Prosopis juliflora (mesquite) have a water barrier composed of the palisade layer present in the seed tegument and galactomannans in the endosperm. Changes in the morphological and physiological states of seeds are usually accompanied by changes in their metabolism. The aim of this study was to detect and characterise the main reserves and their mobilisation during and following germination of P. juliflora seeds. Sections of seeds 0, 24, 48 and 72 h after the onset of the imbibing process were evaluated by light microscopy, and seed reserves were extracted and quantified. Polysaccharides were isolated and characterised by 1H nuclear magnetic resonance (NMR) spectroscopy. In mesquite seeds a well‐developed endosperm, consisting largely of the storage carbohydrate (galactomannans), lies between the seed coat and the cotyledons. Germination was complete after 24 h of imbibition. At this time, morphological changes were observed in stained protein bodies. Chemical analysis showed a decrease in protein levels until 48 h. After 48 h, globular structures were observed in the cotyledon cells, but after 72 h these grains were smaller and their content was reduced. Polarisation microscopy confirmed that this material was composed of starch grains. The 1H NMR spectrum of P. juliflora seeds showed that sucrose was used following germination. Apparently, sucrose is the transport sugar mobilised from reserve stocks for seedling growth. Parallel to endosperm galactomannan degradation, starch is produced transitorily in the cotyledon. Copyright © 2007 Society of Chemical Industry 相似文献
994.
The effect of substituting 0.01 at.% Er for Sc in an Al–0.06Zr–0.06Sc–0.04Si (at.%) alloy subjected to a two-stage aging treatment (4 h/300 °C and 8 h/425 °C) is assessed to determine the viability of dilute Al–Si–Zr–Sc–Er alloys for creep applications. Upon aging, coherent, 2–3 nm radius, L12-ordered, trialuminide precipitates are created, consisting of an Er- and Sc-enriched core and a Zr-enriched shell; Si partitions to the precipitates without preference for the core or the shell. The Er substitution significantly improves the resistance of the alloy to dislocation creep at 400 °C, increasing the threshold stress from 7 to 10 MPa. Upon further aging under an applied stress for 1045 h at 400 °C, the precipitates grow modestly to a radius of 5–10 nm, and the threshold stress increases further to 14 MPa. These chemical and size effects on the threshold stress are in qualitative agreement with the predictions of a recent model, which considers the attractive interaction force between mismatching, coherent precipitates and dislocations that climb over them. Micron-size, intra- and intergranular, blocky Al3Er precipitates are also present, indicating that the solid solubility of Er in Al is exceeded, leading to a finer-grained microstructure, which results in diffusional creep at low stresses. 相似文献
995.
An alternate approach to vasectomy for long-term male contraception following a single intra-vas application of a traditional plant (Azadirachta indica) product having immunomodulatory properties is described. Male Wistar rats of proven fertility were given a single dose (50 microliters) of neem oil in the lumen of the vas deferens on each side; control animals received the same volume of peanut oil. Animals were put on continuous mating 4 weeks after the treatment, with females of proven fertility. While the control animals impregnated the female partners, all males treated with neem oil remained infertile throughout the 8 months of observation period. Epididymal and vas histology were normal without any inflammatory changes or obstruction. The intra-vas administration of neem oil resulted in a block of spermatogenesis without affecting testosterone production; the seminiferous tubules, although reduced in diameter, appeared normal and contained mostly early spermatogenic cells. No anti-sperm antibody could be detected in the serum. Unilateral administration of neem oil in the vas resulted in a significant reduction of testicular size and spermatogenic block only on the side of application; the draining lymph node cells of the treated side also showed enhanced proliferative response to in vitro mitogen challenge. These results indicate that the testicular effects following intra-vas application of neem oil may possibly be mediated by a local immune mechanism. 相似文献
996.
997.
998.
Perinatal events of 180 babies with nuchal cord (umbilical cord entanglement around foetal neck) over one year have been studied. The incidence of nuchal cord was 5.74% of all hospital deliveries. More than one third (39%) of them had tight nuchal cord (TNC) and 61% had loose nuchal cord (LNC). Babies with TNC were more frequently met with foetal distress (51%), prolonged second stage (11%), non-toxaemic accidental haemorrhage (7%) and operative delivery (56%) when compared to babies with LNC and controls (without nuchal cord). Nearly one fourth (24%) of the babies with TNC were born as small for date, had birth asphyxia (61%) and 8.5% died during perinatal period. Perinatal outcome was adversely affected by TNC in comparison to LNC and controls. 相似文献
999.
AD Seidman 《Canadian Metallurgical Quarterly》1995,1(3):247-256
Bradykinin and thrombin caused a time- and dose-dependent stimulation of prostanoid biosynthesis in human dental-pulp fibroblasts, as assessed by the release of prostaglandin E2 (PGE2) and 6-keto-prostaglandin F1 alpha (the stable breakdown product of prostacyclin). The stimulatory effect of bradykinin and thrombin on PGE2 biosynthesis was maximal within 5-10 min. The concentration of bradykinin producing half-maximal stimulation (EC50) of PGE2 and prostacyclin formation was 10 nM. EC50 for thrombin-induced formation of PGE2 and prostacyclin were 0.05 and 0.2 U/ml, respectively. Bradykinin analogues with affinity to the bradykinin B2 receptor, but not those with affinity to the B1 receptor, caused a burst of PGE2 formation. The stimulatory action of bradykinin and thrombin on PGE2 biosynthesis was abolished by two structurally different cyclo-oxygenase inhibitors and significantly reduced by two corticosteroids. Thrombin dose-dependently enhanced the incorporation of [3H]-thymidine into DNA in pulpal fibroblasts by a mechanism that was unrelated to the effect on prostanoid biosynthesis. Bradykinin did not affect thymidine incorporation. Thrombin, but not bradykinin, stimulated the biosynthesis of type 1 collagen in the pulpal fibroblasts. The stimulatory effect of thrombin on collagen biosynthesis was not affected by cyclo-oxygenase inhibitors. These data show that human dental-pulp fibroblasts are equipped with receptors for bradykinin and thrombin linked to enhanced prostanoid biosynthesis. Occupancy of the thrombin receptors also leads to a prostaglandin-independent stimulation of cell proliferation and collagen biosynthesis. 相似文献
1000.