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排序方式: 共有2026条查询结果,搜索用时 15 毫秒
1.
Dr. Menon Raj Gopal M.Ch. AlDelamie Taha FRCS Valliathu John FRCS Zacharias Sunny FRCS Lawati Al Adil FRCS Venkatraman M.Ch. 《Indian Journal of Thoracic and Cardiovascular Surgery》2006,22(3):173-177
Background Despite improving surgical techniques, treatment of heart valve disease in children remains controversial. Somatic growth
and adequate anticoagulation are of concern when children undergo valve replacement. We conducted this study to evaluate the
performance of valves in this age group.
Methods 42 children under the age of 13 years who underwent valve replacement were included in this study. Totally, 50 valves were
implanted in 42 patients: 48 were mechanical prostheses, two were bioprosthetic both in pulmonary position. 37 (74%) valves
were implanted in mitral position, 10 (20%) in aortic position, 1 (2%) in tricuspid position and 2 (4%) in pulmonary position.
Preoperatively, 14 (33,3%) patients were in New York Heart Association (NYHA) class IV, while 27 (64.2%) were in NYHA class
III.
Results There were 2 (4.7%) hospital deaths and 2 (4.7%) late deaths while 2 (4.7%) patients were lost to follow up. The mean follow
up period was 9.4 yrs. 35 (83.3%) patients are in NYHA Class I and free of all medications except warfarin. 3 (7.1%) patients
have undergone 5 successful pregnancies. The median INR was 2.23. Major thrombo-embolic episode occurred in 1 (2.3%) patient.
Conclusions In view of the problems of sizing, anticoagulation and need for re-operation at an early age, there is a reluctance to replace
valves in children. This study shows that despite these problems, valve replacement can be undertaken safely and successfully
in children, when repair has failed or not technically feasible. 相似文献
2.
Predictors of clustering of tuberculosis in Greater Vancouver: a molecular epidemiologic study 总被引:3,自引:0,他引:3 下载免费PDF全文
3.
Predicting outbreaks: a spatial risk assessment of West Nile virus in British Columbia 总被引:1,自引:0,他引:1
Kaoru Tachiiri Brian Klinkenberg Sunny Mak Jamil Kazmi 《International journal of health geographics》2006,5(1):21-21
Background
West Nile virus (WNv) has recently emerged as a health threat to the North American population. After the initial disease outbreak in New York City in 1999, WNv has spread widely and quickly across North America to every contiguous American state and Canadian province, with the exceptions of British Columbia (BC), Prince Edward Island and Newfoundland. In this study we develop models of mosquito population dynamics for Culex tarsalis and C. pipiens, and create a spatial risk assessment of WNv prior to its arrival in BC by creating a raster-based mosquito abundance model using basic geographic and temperature data. Among the parameters included in the model are spatial factors determined from the locations of BC Centre for Disease Control mosquito traps (e.g., distance of the trap from the closest wetland or lake), while other parameters were obtained from the literature. Factors not considered in the current assessment but which could influence the results are also discussed. 相似文献4.
J Chhabra Y-Z Li H Alkhouri A E Blake Q Ge C L Armour J M Hughes 《The European respiratory journal》2007,29(5):861-870
Degranulating mast cells are increased in the airway smooth muscle (ASM) of asthmatics, where they may influence ASM function. The aim of the present study was to determine whether histamine and tryptase modulate ASM cell granulocyte-macrophage colony-stimulating factor (GM-CSF) and RANTES (regulated on activation, normal T-cell expressed and secreted) release and also to examine which receptors are involved in this release. Confluent, quiescent ASM cells from asthmatic and nonasthmatic donors were treated with histamine (1 microM-100 microM) with and without histamine receptor antagonist pre-treatment, or the protease-activated receptor (PAR)-2 agonists tryptase (0.5-5 nM) and SLIGKV (100 and 400 microM). The cells were then stimulated with interleukin (IL)-1beta and/or tumour necrosis factor (TNF)-alpha (10 ng.mL(-1)) or left unstimulated for 24 h. Release of GM-CSF and RANTES was determined by ELISA and prostaglandin (PG)E(2) measured by enzyme immunoassay. Neither histamine nor tryptase induced ASM GM-CSF or RANTES secretion. However, histamine increased IL-1beta-induced GM-CSF release and markedly reduced TNF-alpha-induced RANTES release by both asthmatic and nonasthmatic cells to a similar extent, but did not modulate PGE(2) release. All changes involved activation of the histamine H1 receptor as they were partially or fully blocked by chlorpheniramine, but not ranitidine. Tryptase, via its proteolytic activity, also potentiated GM-CSF, but not RANTES, release from asthmatic and nonasthmatic ASM cells induced by both cytokines. PAR-2 involvement in the tryptase potentiation was unlikely because SLIGKV had no effect. In conclusion, mast cells, through histamine and tryptase, may locally modulate airway smooth muscle-induced inflammation in asthma. 相似文献
5.
6.
Asymptomatic infection with Loa loa, an eye worm, is reported in a 32-year old Zambian woman. The patient revealed up to 28% eosinophilia but microfileraemia was not noticed. One gravid female parasite 56 X 0.56 mm, extracted from lower lid of left eye of the patient, is described. Treatment with diethylcarbamazine (DEC) extended over three weeks was successful against another parasite in tissues. 相似文献
7.
Deepu Banerji Rajesh Acharya Sanjay Behari Devendra K. Chhabra Dr. Vijendra K. Jain MCh 《Neurosurgical review》1997,20(1):25-31
The choice of a surgical approach for multi-level cervical spondylotic myelopathy (CSM) and ossification of the posterior longitudinal ligament (OPLL) is still a controversial issue. While most of the surgeons are still performing decompression by laminectomy some are doing multi-level anterior decompression. Few neurosurgeons are performing decompression by corpectomy. We have treated 26 patients by median cervical corpectomy during the last 4 years. These patients were followed up for a mean period of 25 months. Twenty one (80%) patients had a good outcome, 2 patients remained unchanged and 3 expired. Review of the literature and our experience indicates that patients with CSM and OPLL should be operated by median cervical corpectomy (anterior approach). 相似文献
8.
A study was conducted on 140 pregnant women at and after 28 weeks of pregnancy for finding out the relationship of cervical length and position with onset of preterm labour. Incidence of preterm labour was significantly higher (p < 0.001) in women with central position of cervix (54.67%) than that with posterior position of cervix (10.77%). Onset of preterm delivery was closely related to cervical length of 2.5 cm or less irrespective of central (82.75%) or posterior (20%) position of cervix (p < 0.001). 相似文献
9.
10.
Sunny E Ohia S Olubusayo Awe Catherine A Opere Angela M LeDay Lydia C Harris Kaustubh Kulkarni Najam A Sharif 《Journal of ocular pharmacology and therapeutics》2003,19(6):599-609
The glucose deprivation-induced release of [3H]D-aspartate was studied in bovine and human retinas in a superfusion apparatus. [3H]D-aspartate release was significantly increased upon omitting glucose in the superfusion buffer. This effect was dependent on external Ca2+ because L- and N-type Ca2+-channel blockers, such as diltiazem (1 microM), nitrendipine (1 microM), and omega-conotoxin (100 nM), significantly reduced the effect of glucose-deprivation induced release of [3H]D-aspartate. Furthermore, while glutamate receptor agonists (L-glutamate, N-methyl-D-aspartate, but not kainate) potentiated the effects of glucose deprivation, antagonists (MK-801, MCPG, ifenprodil, and L-AP3) at these receptors blocked the glucose deprivation-induced release process. Taken together, these studies have demonstrated that under conditions of glucose deprivation, as may happen during ischemic events in vivo, the retinal glutamatergic nerve endings and/or glial cells promote the efflux of [3H]D-aspartate into the extracellular environment. This process appears to be receptor-mediated and dependent on extracellular Ca2+ and is similar to previous reports pertaining to brain tissues. 相似文献