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排序方式: 共有6444条查询结果,搜索用时 15 毫秒
71.
Kathirvel S Prakash A Lokesh BN Sujatha P 《Anesthesia and analgesia》2000,91(4):1029-31, table of contents
Implications: This case report describes the anesthetic considerations for a patient with paroxysmal nocturnal hemoglobinuria. Specific strategies to be applied in the perioperative period to prevent hemolytic episodes and venous thrombosis are also discussed. 相似文献
72.
Robert T. Jackson Nawal Al Hamad Mona Al-Somaie Nawal Al Guoad Prasanna Prakash 《Ecology of food and nutrition》2004,43(1):61-75
Anemia remains a significant worldwide public health problem. Most studies of anemia and iron deficiency, the major cause of anemia, have targeted small children and reproductive age women. Much less is known about anemia in other lifecycle groups, especially preschool age children, prepubertal boys and girls, or in older adults. Yet recent studies indicate that anemia may increase the risk for chronic diseases and accelerate declining function in older adults. We examined anemia throughout the lifecycle in Kuwait by analyzing data from the 2002 Kuwait Nutrition Surveillance Program. Over 13,000 individuals of both sexes representing all ages were studied. The prevalence of anemia was higher in females than males between 6 months and 3 years. From age 4 to 14 years, there was a reversal with males having a higher rate of anemia. Older females had a lower prevalence of anemia than younger females. These results imply certain policy options. 相似文献
73.
腹腔镜下精索血管高位离断后大鼠睾丸的形态学改变 总被引:1,自引:2,他引:1
目的观察腹腔镜FowlerStephens(FS)手术对青春发育前、中、后期睾丸形态结构的影响。方法30d龄Wistar大鼠麻醉后建立CO2气腹,分别行右侧精索血管游离术(对照组)、右侧腹腔内精索血管离断术(FS组),术后将每大组大鼠再分成7个小组(对照组每小组5只;FS组每小组8~12只),分别在术后第9d(青春发育期前)、20d和45d(青春发育期)、90d和180d(性发育成熟期)、360d和540d(中年期),获取睾丸进行详尽的组织形态学研究。结果FS手术可以引起术后不同时期共85%手术侧睾丸出现轻度(血睾屏障受损为主)、重度(唯支持细胞综合征为主)和完全萎缩(丧失睾丸基本结构,无生殖细胞存活);当轻度或重度萎缩,对侧睾丸未受累;当完全萎缩(49%),对侧睾丸在手术45d后,100%出现轻度(青春发育期后)或重度(中年期)萎缩;间质细胞增生或腺瘤可发生于轻、重和完全萎缩睾丸中(P<0.001)。结论腹腔镜FS动物模型可用幼年大鼠建立;该手术可以引起从青春发育前期至中年期较高比例、不同程度的睾丸萎缩,其中完全萎缩可以影响到对(健)侧睾丸,而可能引起青春发育期后生殖力下降或丧失;睾丸间质肿瘤可以较高比例地发生于不同程度萎缩睾丸中。 相似文献
74.
A Nigam V K Singh P Dubay K Pandey A Bhagoliwal A Prakash 《International journal of gynaecology and obstetrics》2004,86(3):398-400
Efficacy of misoprostol was studied for induction of labor at term. Seventy patients were randomized to Group A (n = 36, oral misoprostol 50 microg four hourly to maximum of 5 doses) and B (n = 34, continuous oxytocin infusion). Induction-delivery interval was shorter with misoprostol (7.7 +/- 2.8 h against 14.3 +/- 4.8 h with oxytocin) but the rates of vaginal delivery, cesarean, neonatal outcome variables were similar. Hence, misoprostol is an effective agent for induction of labor at term. 相似文献
75.
Chen-Bee CH Polley DB Brett-Green B Prakash N Kwon MC Frostig RD 《Journal of neuroscience methods》2000,97(2):157-173
Intrinsic signal imaging (ISI) measures changes in light reflectance from the illuminated cortex (intrinsic signals or IS) attributed to various vascular and metabolic sources that, when using illumination in the 600 nm range, appear to co-localize with neuronal activity. Given the multiple sources contributing to the collected IS, the common practice of averaging across an extended post-stimulus time epoch before dividing by baseline data typically visualizes evoked IS overlying both the cortical tissue and the large surface blood vessels. In rat PMBSF, the contribution from these vessels are problematic as they do not co-localize with known PMBSF function. Determining a means for quantifying the evoked IS area poses an additional challenge. Here, we describe how exploiting IS collected shortly after stimulus onset (within 1.5 s), which coincides with fast oxygen consumption of active neurons, visualizes evoked IS overlying the cortical tissue without the large surface vessels. We also describe how the use of absolute thresholds combined with a baseline determined from data collected immediately prior to stimulus onset (within 1 s) targets most precisely a specific evoked IS amplitude, a method that should be especially useful when evoked areas are expected to occupy a substantial portion of the total imaged area and/or when peak activity is expected to differ between subjects. 相似文献
76.
We have used pathway-specific cDNA arrays coupled with analysis of gene promoter regions to identify novel genes that may mediate the toxic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in the thymus. C57BL/6 mice were injected ip with 50 microg/kg TCDD, and 3, 6, or 24 h later, RNA was extracted from the thymus and subjected to microarray analysis. Several members of the TNF and TNFR family were induced following TCDD exposure, including receptor/ligand pairs Ltbeta-R/LIGHT, OX40/OX40L and TNF-alpha/TNFR1. In addition, Fas and CD30 were also upregulated. Pro-apoptotic bcl-2 gene family members Bax and Hrk, among others, were also induced, as were pro-survival bcl-2 family genes Bcl-x and Bcl-w. Cell-cycle regulator p21Cip1 was also induced. In addition, we analyzed the promoter regions of genes induced by TCDD for the presence of dioxin-responsive elements (DREs). The Fas and LIGHT gene promoters were found to contain DREs as analyzed by Matinspector Web-based search algorithm. Furthermore, binding of the aryl hydrocarbon receptor (AhR) to the DREs present on these genes was confirmed by chromatin immunoprecipitation. Given that several of the genes, including Fas, LIGHT, and CD30 are involved in negative selection of T cells in the thymus, our studies suggest that TCDD-induced upregulation of these genes may enhance negative selection leading to thymic atrophy. 相似文献
77.
78.
David G. Zacharias Timothy J. Nelson Paul S. Mueller C. Christopher Hook 《CTS Clinical and Translational Science》2012,5(5):422-427
Embryonic stem cell (ES) technology has advanced considerably within the past three decades and has gained prominent distinction within the emerging field of regenerative medicine. As it now enters the nascent stages of clinical application, many hopes and expectations arise along with questions as to where the technology will go. This paper evaluates the technical and practical obstacles that must be overcome before it can fully translate into the clinical context, the existence of strong opposition to the technology, political and legal barriers that have impeded its progression, and the role of healthcare reform in creating new social and economic priorities. In contrast to the technological imperative, a driving force seeking to implement the most recent scientific advances into medical practice, we refer to such translational obstacles as “technological impedance.” Rather than expending inordinate effort to preserve existing systems that continue to possess major hurdles, we advocate fostering interdisciplinary approaches in the development of new generation platforms and embracing disruptive innovations that create solutions to technological impedance and move us forward in healthcare delivery. Clin Trans Sci 2012; Volume 5: 422–427 相似文献
79.
Anand Kumar Singh Manindra Nath Tiwari Om Prakash Mahendra Pratap Singh 《Current Neuropharmacology》2012,10(1):64-71
Cypermethrin, a class II pyrethroid pesticide, is used to control insects in the household and agricultural fields. Despite beneficial roles, its uncontrolled and repetitive applications lead to unintended effects in non-target organisms. Cypermethrin crosses the blood-brain barrier and induces neurotoxicity and motor deficits. Cypermethrin prolongs the opening of sodium channel, a major site of its action, leading to hyper-excitation of the central nervous system. In addition to sodium channel, cypermethrin modulates chloride, voltage-gated calcium and potassium channels, alters the activity of glutamate and acetylcholine receptors and adenosine triphosphatases and induces DNA damage and oxidative stress in the neuronal cells. Cypermethrin also modulates the level of neurotransmitters, including gamma-aminobutyric acid and dopamine. It is one of the most commonly used pesticides in neurotoxicology research not only because of its variable responses depending upon the doses, time and routes of exposure and strain, age, gender and species of animals used across multiple studies but also owing to its ability to induce the nigrostriatal dopaminergic neurodegeneration. This article describes the effect of acute, chronic, developmental and adulthood exposures to cypermethrin in experimental animals. The article sheds light on cypermethrin-induced changes in the central nervous system, including its contribution in the onset of specific features, which are associated with the nigrostriatal dopaminergic neurodegeneration. Resemblances and dissimilarities of cypermethrin-induced nigrostriatal dopaminergic neurodegeneration with sporadic and chemicals-induced disease models along with its advantages and pitfalls are also discussed. 相似文献
80.
Nandita Joshi Chhavi Sarabpreert Sharma Sai Jai Prakash Sharma 《Indian Journal of Critical Care Medicine》2012,16(4):238-240
We present a rare case in which a young girl ingested a solution of a hair-removing soap. The ingestion resulted in profound hypokalemia and severe acidosis leading to flaccid paralysis, respiratory arrest and ventricular arrhythmias. Ultimately the patient made complete recovery. The soapwas found to contain barium sulfide. The degree of paralysis and acidosis appeared to be directly related to serum potassium levels. 相似文献