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71.
Left-handedness is a normal variant but also may result from early-life brain insults. Speech typically resides in the left cerebral hemisphere in normal subjects. In 170 subjects with past brain injuries, bilateral or right hemisphere speech lateralization, determined by the intracarotid amobarbital procedure, was more frequent in females (19 vs 5, p = 0.003) as was left-handedness (26 vs 10, p = 0.004). This could be attributed to greater plasticity or functional symmetry in females. 相似文献
72.
Cefpodoxime is a oral third generation cephalosporin active against most of gram positive and gram negative bacteria except
Pseudomonas, B. fragilis and Entrococcous. Clinical studies have confirmed efficacy of cefpodoxime in acute otitis media,
sinusitis and tosillopharyngitis. Twice daily administration and safety profile increases compliance and decreases failure
rate. It has a role as switch over therapy from intravenous ceftriaxone in serious respiratory tract infections (RTIs). In
areas where common respiratory pathogens show decreased sensitivity to penicillins and macrolides cefpodoxime can be used
as empirical first line therapy in respiratory tract infections. It seems to be a promising molecule in pediatric typhoid
fever because of its excellent activity against Salmonella species but clinical trials are limited. 相似文献
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A comparative study of the effect of oxidative stress on the cytoskeleton in human cortical neurons 总被引:1,自引:0,他引:1
Allani PK Sum T Bhansali SG Mukherjee SK Sonee M 《Toxicology and applied pharmacology》2004,196(1):29-36
Cytoskeleton disruption is a process by which oxidative stress disrupts cellular function. This study compares and contrasts the effect of oxidative stress on the three major cytoskeleton filaments, microfilaments (MFs), microtubule (MT), and vimentin in human cortical neuronal cell line (HCN2). HCN2 cells were treated with 100 microM tertiary butylhydroperoxide (t-BuOOH), a free radical generating neurotoxin for 1, 3, or 6 h. Cell viability studies demonstrated significant cell death although the morphology studies showed that there was a substantial loss in neurites of neurons treated with t-BuOOH for 6 h. Because the cytoskeleton plays a role in neurite outgrowth, the effect of oxidative stress on the cytoskeletal was studied. In neurons subjected to oxidative stress for 30 min or 1 h, there were no major changes in microfilament distribution though there was altered distribution of microtubule and vimentin filaments as compared to controls. However, loss and disruption of all the three cytoskeletal filaments was observed at later times (3 and 6 h), which was confirmed by Western Blot analysis. Further studies were done to measure the gene expression levels of actin, tubulin, and vimentin. Results indicated that the overall loss of the cytoskeletal proteins in neurons treated with free radical generating toxin might not be a direct result of the downregulation of the cytoskeletal genes. This study shows that free radical generation in human neurons leads to the disruption of the cytoskeleton, though there may be a difference in the susceptibility to oxidative stress among the individual components of the cytoskeletal filaments. 相似文献
75.
Signalling pathways activated by all-trans-retinoic acid in acute promyelocytic leukemia cells 总被引:5,自引:0,他引:5
Kambhampati S Verma A Li Y Parmar S Sassano A Platanias LC 《Leukemia & lymphoma》2004,45(11):2175-2185
76.
Chemotherapy-induced and/or radiation therapy-induced oral mucositis--complicating the treatment of cancer 总被引:3,自引:0,他引:3 下载免费PDF全文
The term mucositis is coined to describe the adverse effects of radiation and chemotherapy treatments. Mucositis is one of the most common adverse reactions encountered in radiation therapy for head and neck cancers, as well as in chemotherapy, in particular with drugs affecting DNA synthesis (S-phase-specific agents such as fluorouracil, methotrexate, and cytarabine). Mucositis may limit the patient's ability to tolerate chemotherapy or radiation therapy, and nutritional status is compromised. It may drastically affect cancer treatment as well as the patient's quality of life. The incidence and severity of mucositis will vary from patient to patient. It will also vary from treatment to treatment. It is estimated that there is 40% incidence of mucositis in patients treated with standard chemotherapy and this will not only increase with the number of treatment cycles but also with previous episodes. Similarly, patients who undergo bone marrow transplantation and who receive high doses of chemotherapy have a 76% chance of getting mucositis. Patients receiving radiation, in particular to head and neck cancers, have a 30% to 60% chance. The exact pathophysiology of development is not known, but it is thought to be divided into direct and indirect mucositis. Chemotherapy and/or radiation therapy will interfere with the normal turnover of epithelial, cells leading to mucosal injury; subsequently, it can also occur due to indirect invasion of Gram-negative bacteria and fungal species because most of the cancer drugs will cause changes in blood counts. With the advancement in cytology, a more precise mechanism has been established. With this understanding, we can select and target particular mediators responsible for the mucositis. Risk factors such as age, nutritional status, type of malignancy, and oral care during treatment will play important roles in the development of mucositis. Many treatment options are available to prevent and treat this condition, but none of them can completely prevent or treat mucositis. More and more pathological methods are being developed to understand this condition so that better therapeutic regimens can be selected. Emphasis also should be made in assessing the patient's psychologic condition, particular depressive disorders. This is important because treatment with antidepressants will not only contribute in lifting depression but also reduces pain somatization. Although mucositis is rarely life-threatening, it will interfere with treatment of cancer to a great extent. 相似文献
77.
Dowdy SC Constantinou CL Hartmann LC Keeney GL Suman VJ Hillman DW Podratz KC 《Gynecologic oncology》2003,91(3):563-568
OBJECTIVE: Previous reports indicate that cytoreduction and salvage therapy with P32 or whole abdominal radiation may improve survival in patients with positive findings at second-look laparotomy (SLL). The aim of this investigation was to determine whether these findings held true with extended follow-up and a larger patient cohort. METHODS: From 1977 (the year platinum-based chemotherapy was introduced to our institution) to 1989, 150 patients had persistent disease at SLL. Relevant clinical information was extracted through retrospective chart review. RESULTS: One hundred forty-five patients were followed until death, with a median follow-up of 15.4 years for the 5 living patients. Median actuarial survival from the time of SLL was 18 months. Tumor grade (P = 0.003) and pre- and post-SLL tumor size (P < 0.0001) were significant determinants of survival by univariate analysis. Patients with microscopic disease or those with < or =1 cm disease rendered microscopic at SLL had improved survival relative to those with < or =1 cm and macroscopic disease following SLL (P = 0.03) (median survivals of 3.3, 2.5, and 1.4 years, respectively). In contrast, median survival of those with >1 cm disease cytoreduced to microscopic disease was no different than those with macroscopic residual, even if < or =1 cm (1.3 and 1.0 years, respectively). After adjusting for tumor size, salvage treatment was not a significant predictor of survival. CONCLUSION: With long-term follow-up there was no suggestion that the type of salvage therapy (e.g., P32 or WART) influenced survival. Rather, low-grade disease and low tumor burdens following cytoreduction were associated with improved survival on multivariate analysis. 相似文献
78.
79.
Posterior scleritis mimicking macular serpiginous choroiditis 总被引:1,自引:0,他引:1
Sonika Narang S Kochhar S Srivastava M Gupta R Sood S 《Indian journal of ophthalmology》2003,51(4):351-353
An unusual case of posterior scleritis mimicking macular serpiginous choroiditis is reported. 相似文献
80.