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排序方式: 共有8103条查询结果,搜索用时 281 毫秒
41.
A retrospective study of anaemia in pregnancy in rural Kelantan was conducted. The study sample consist of 9,860 mothers who had antenatal care at one of the 102 rural health clinics selected and had delivered a live baby. Anaemia in pregnancy was determined by reviewing the antenatal records for the haemoglobin level recorded at the first and last antenatal visit. Estimation of haemoglobin was done either by photocalorimetric methods or the Sahli's method in these rural clinics. At the time of booking, 47.5% of the mothers were anaemic by WHO criteria (Hb < 11.0 g/dl), with 1.9% having less than 9.0 g/dl. Age of mother, parity and late gestational age at the first antenatal visit were associated with anaemia during pregnancy at the time of booking. However, practise of contraception by the mother did not show any association with anaemia in pregnancy. There were 594 mothers (6.0%) who delivered a baby weighing less than 2.5 kg. There was no association between the low birth weight of the child and the status of anaemia in the mother at the last antenatal visit. 相似文献
42.
1. We have investigated the differences between the nitric oxide synthase inhibitor L-NMMA, the guanylate cyclase inhibitor methylene blue and the potassium channel blockers apamin and charybdotoxin or apamin and iberiotoxin, in their abilities to increase vasoconstrictor responses in rat small mesenteric arterial rings. 2. When administered during the maintained contraction to PGF2alpha (10 microM), L-NMMA (100 microM) or the combination of apamin (0.7 microM) and charybdotoxin (0.1 microM) significantly increased the contractile response. Methylene blue (10 microM) increased the contraction, but this did not reach significance. However, apamin (0.7 microM) and iberiotoxin (0.1 microM) also significantly increased the contractile response. 3. The combination of L-NMMA or methylene blue with apamin/charybdotoxin produced significantly greater increases in the contractile response to PGF2alpha than achieved individually. 4. Relaxations to acetylcholine (10 microM) were significantly reduced by L-NMMA or methylene blue but not by apamin in combination with charybdotoxin or iberiotoxin. 5. Since apamin/iberiotoxin had similar effects to apamin/charybdotoxin, it is likely that the actions of these agents involve direct actions on smooth muscle potassium channels rather than inhibition of endothelium-derived hyperpolarising factor (EDHF). These results suggest that endothelium-derived nitric oxide but not EDHF has a major role in modulating vascular tone under these conditions. 相似文献
43.
Abdullah MH Van Arsdell GS Hornberger LK Adatia I 《The Annals of thoracic surgery》2000,70(6):94-2149
We report a patient with stenosis of the native ascending aorta after palliation of hypoplastic left heart syndrome and aortic atresia. We describe the approach to diagnosis, temporary support with extracorporeal membrane oxygenation, and successful surgical reintervention. Stenosis of the native ascending aorta is an important, potentially reversible cause of acute, early postoperative ventricular dysfunction. 相似文献
44.
Ginkgo biloba extract ameliorates ischemia reperfusion-induced renal injury in rats. 总被引:4,自引:0,他引:4
G?ksel Sener Emre Sener Ozer Sehirli Ayliz Velio?lu O?ün? Sule Cetinel Nursal Gedik Abdullah Sakarcan 《Pharmacological research》2005,52(3):216-222
There is increasing evidence to suggest that reactive oxygen metabolites (ROMs) play a role in the pathogenesis of ischemia/reperfusion injury (I/R) in the kidney. This study was designed to determine the possible protective effect of Ginkgo biloba extract (EGb) on renal ischemia/reperfusion (I/R) injury. Wistar albino rats were unilaterally nephrectomized, and 15 days later they were subjected to 45 min of renal pedicle occlusion followed by 6 h of reperfusion. Ginkgo biloba extract (EGb) (50 mg kg(-1) day(-1)) or saline was administered twice, 15 min prior to ischemia and immediately before the reperfusion period. At the end of the treatment period, all rats were decapitated. Kidney samples were taken for histological examination or determination of the renal malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity and collagen content. Production of reactive oxidants was monitored by chemiluminescence (CL) assay. Creatinine and urea concentrations in blood were measured for the evaluation of renal function. Tumor necrosis factor-alpha (TNF-alpha) and lactate dehydrogenase (LDH) were also assayed in serum samples. Ischemia/reperfusion caused a significant decrease in GSH level, which was accompanied with significant increases in MDA level, MPO activity and collagen content of kidney tissues. Similarly, serum BUN and creatinine levels, as well as LDH and TNF-alpha, were elevated in the I/R group as compared to control group. On the other hand, EGb treatment reversed all these biochemical indices, as well as histopathological alterations, which were induced by I/R. The findings imply that ROMs play a causal role in I/R-induced renal injury and EGb exerts renoprotective effects probably by the radical scavenging and antioxidant activities. 相似文献
45.
G Patil MI Khan DK Patel S Sultana R Prasad I Ahmad 《Environmental toxicology and pharmacology》2012,34(2):436-445
Dolomite is a natural mineral of great industrial importance and used worldwide, thus millions of workers are at risk of occupational exposure. Its toxicity is however, meagerly documented. In the present investigation, a dolomite powder obtained from its milling unit was analyzed by some standard methods namely, optical microscopy, transmission electron microscopy and dynamic light scattering. Results showed that dolomite powder contained particles of different shapes and size both microparticles (MPs) and nanoparticles (NPs), suggesting potential occupational exposure of these particles. An attempt was therefore, made to investigate dolomite toxicity in a particle size-dependent manner in human lung epithelial cells A(549). The comparative toxicity evaluation of MPs and NPs was carried out by assessing their effects on cell viability, membrane damage, glutathione, reactive oxygen species (ROS), lipid peroxidation (LPO), micronucleus (MN) and proinflammatory cytokines, namely tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6). These markers of cytotoxicity, genotoxicity and inflammation were assayed in cells exposed to MPs and NPs in a dose-and time-dependent manner. Invariably, their toxic effects were dose-and time-dependent while NPs in general were significantly more toxic. Notably, NPs caused oxidative stress, genotoxicity and inflammatory responses, as seen by significant induction of ROS, LPO, MN, TNF-α, IL-1β and IL-6. Thus, the study tends to suggest that separate health safety standards would be required for micrometer and nanometer scale particles of dolomite. 相似文献
46.
Nur Aziah Hanapi Ahmad Saifuddin Mohamad Arshad Jafri Malin Abdullah Tengku Sifzizul Tengku Muhammad Siti R. Yusof 《Journal of pharmaceutical sciences》2021,110(2):698-706
Neurotherapeutic potentials of Centella asiatica and its reputation to boost memory, prevent cognitive deficits and improve brain functions are widely acknowledged. The plant's bioactive compounds, i.e. asiaticoside, madecassoside and asiatic acid were reported to have central nervous system (CNS) actions, particularly in protecting the brain against neurodegenerative disorders. Hence, it is important for these compounds to cross the blood-brain barrier (BBB) to be clinically effective therapeutics. This study aimed to explore the capability of asiaticoside, madecassoside and asiatic acid to cross the BBB using in vitro BBB model from primary porcine brain endothelial cells (PBECs). Our findings showed that asiaticoside, madecassoside and asiatic acid are highly BBB permeable with apparent permeability (Papp) of 70.61 ± 6.60, 53.31 ± 12.55 and 50.94 ± 10.91 × 10?6 cm/s respectively. No evidence of cytotoxicity and tight junction disruption of the PBECs were observed in the presence of these compounds. Asiatic acid showed cytoprotective effect towards the PBECs against oxidative stress. This study reported for the first time that Centella asiatica compounds demonstrated high capability to cross the BBB, comparable to central nervous system drugs, and therefore warrant further development as therapeutics for the treatment of neurodegenerative diseases. 相似文献
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