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Brain cyclooxygenases (COX), the rate-limiting enzyme in prostaglandin synthesis, is rapidly and transiently induced by convulsions in hippocampal and cortical neurons. Previous studies have explored the protective effect of naproxen (non-selective COX-inhibitor) or rofecoxib (selective COX-2 inhibitor) against chemical kindling in mice. With this background, the present study was designed to explore the possible effect of nimesulide (a preferential COX-2 inhibitor) against pentylenetetrazol (PTZ)-induced kindling epilepsy in mice. To induce kindling, PTZ was injected in a subconvulsive dose (40 mg/kg, i.p.) every other day for 15 days. Nimesulide (2.5 or 5 mg/kg, p.o.) was administered each day 45 min before either PTZ or vehicle challenge. The intensity of kindling was assessed immediately after PTZ administration according to a prevalidated scoring scale. On 16th day i.e. 24 h after the last dose of PTZ, animals were sacrificed and various biochemical parameters were assessed in the whole brain. Compared with normal control group, PTZ-kindled mice had significantly higher levels of malondialdehyde, nitrite, myeloperoxidase but had lower levels of reduced glutathione in the whole brain homogenate. Chronic treatment with nimesulide (2.5 or 5 mg/kg, p.o.) for 15 days showed significant decrease in kindling score and could play a role in controlling the accompanying biochemical alterations due to PTZ. These results suggested that nimesulide, a preferential COX-2 inhibitor offered neuroprotection against PTZ-induced kindling in mice. 相似文献
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The case of a horn-like hyperplasia of the caruncle of the left eye in a 3-month-old child is reported. An atavistic origin of this growth as a vestigial upper incisor is suggested from the anatomical location of the horn. 相似文献
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A commercially available ADAC Pinnacle(3) radiation treatment planning system has been used to model electron beams from a Varian Clinac 2300C/D in the energy range of 6 to 22 MeV. Prior to clinical use, the dosimetric characteristics of the beams have to be modeled accurately. As a first step for beam modeling, a number of dose profile and depth dose measurements were taken at standard source-to-surface distance (SSD) of 100 cm. Dose profiles and depth dose measurements at extended SSDs up to 120 cm are important for ascertaining accuracy of the model, as well as their clinical usefulness in the treatment of some sites (e.g., head-and-neck tumors). Modeled and measured beam data were compared. Over 98% of comparison points (modeled vs. measured) at 100-cm SSD were within 2.5% or 2.5 mm. At 110 cm SSD, over 98% of compared points were within 4% or 4 mm, and at 120-cm SSD, over 98% of compared points were within 5% or 5 mm. Overall, more than 98% of compared points were within 4% or 4 mm. Better models were produced for lower energies (6 to 15 MeV) than higher energies (18 and 22 MeV). For 6, 9, 12, and 15 MeV, 89% of compared points were within 2% or 2 mm. For 18- and 22-MeV electron energies, 75% and 67%, respectively, were within 2% or 2 mm. These results are consistent with the recommendations of AAPM Task Group Report 53. 相似文献
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Cauda equina nerve sheath tumors are usually small, well-encapsulated tumors. Sometimes they may attain very large proportions, cause extensive bony changes, and resemble ependymomas in the cauda equina. They may also infiltrate into adjacent soft tissue planes and retroperitoneal spaces and yet be histologically benign. An awareness of this entity ensures aggressive surgical removal at the time of exploration. Primary neuro-fibrosarcomas or malignant changes in primary nerve sheath tumors of the cauda equina are seen in patients with neurofibromatosis. 相似文献
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Myopodin, a synaptopodin homologue, is frequently deleted in invasive prostate cancers. 总被引:4,自引:0,他引:4
F Lin Y P Yu J Woods K Cieply B Gooding P Finkelstein R Dhir D Krill M J Becich G Michalopoulos S Finkelstein J H Luo 《The American journal of pathology》2001,159(5):1603-1612
Prostate cancer is one of the leading causes of cancer-related deaths for men in the United States. Like other malignancies, prostate cancer is underscored by a variety of aberrant genetic alterations during its development. Although loss of heterozygosity or allelic loss is frequently identified among prostate cancers, few genes have been identified thus far as critical to the development of invasive prostate cancers. In this report, we used the recently developed technology, the "differential subtraction chain," to perform a genome-wide search for sequences that are deleted in an aggressive prostate cancer. Among the deleted sequences, we found that one sequence was deleted in >50% of prostate cancers we tested. We mapped this sequence to chromosome 4q25 by screening the Genebridge 4 hamster radiation panel with primers specific to this probe, and subsequently identify a 54-kb minimal common deletion region that contains the sequence encoding myopodin. Sequence analysis indicates that myopodin shares significant homology with synaptopodin, a protein closely associated with podocyte and neuron differentiation. Further study shows that frequent complete or partial deletions of the myopodin gene occurred among invasive prostate cancer cases (25 of 31 cases, or 80%). Statistical analysis indicates that deletion of myopodin is highly correlated with the invasiveness of prostate cancers, and thus may hold promise as an important prognostic marker for prostate cancers. 相似文献
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Navneet Kumar Goel Ankit Khurana Varun Narula Ashish Goyal 《Indian Journal of Orthopaedics》2021,55(3):758
Most metatarsal neck fractures can be successfully treated non-operatively in a cast boot. Displaced metatarsal neck fractures tend to be less stable and have a propensity for the distal fragment to angulate, secondary to the strong flexor tendons, which often forces the distal fracture fragment in a plantar direction and leads to relative metatarsal shortening. Most literature is focussed on antegrade fixation of metatarsal neck fractures using pre-bent K wires or thin elastic nails. Apart from the technical challenges, this technique is limited when bones are osteoporotic as the pre-bent distal end of the K-wire may penetrate the plantar cortex of the proximal metatarsal and prevent the wire from entering the medullary canal of the metatarsal and advancing to the fracture site. Furthermore, when the medullary canal is narrow especially in Asian patients, it may be difficult to pass a bent K-wire through the isthmus of the metatarsal shaft. We describe an innovative technique of closed transverse wiring of the metatarsal head necks that has a distinct advantage in Asian population with osteoporotic bones. With percutaneous manipulation using digital pressure, closed reduction of fracture fragments of the most displaced fracture is done under fluoroscopic guidance to achieve a satisfactory alignment followed by closed transverse wiring of the metatarsal heads. With this procedure, adjacent fractures remain stable within an acceptable range because of intermetatarsal ligaments connected to the adjacent intact head. Our technique has a relatively short operating time and allows for early motion of the metatarso-phalangeal joint. This is especially useful for those with osteoporosis, narrow canal, soft tissue compromise, intra-operative failure of ante-grade pinning and in scenarios of limited surgical equipment/expertise. 相似文献
10.
Hendriks Olivia Wei Yimeng Warrier Varun Richards Gareth 《Archives of sexual behavior》2022,51(4):2077-2089
Archives of Sexual Behavior - Previous research indicates a link between autism and transgender and gender-diverse identities, though the association is not yet fully understood. The current study... 相似文献