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91.
Three 1,2-benzothiazine derivatives were synthesized, and their analgesic/anti-inflammatory efficacy and their effects on gastric irritation were evaluated. Among the three compounds, 39 exhibited the most potent analgesic action, but the effect was weaker than that of piroxicam. Nonetheless, the compound showed 4 times more potent analgesic action with less gastric damage than did ibuprofen. These compounds did not show anti-inflammatory effect at an oral dose of 5 mg/kg.  相似文献   
92.
Many conventional anticancer drugs display relatively poor selectivity for neoplastic cells, in particular for solid tumors. Furthermore, expression or development of drug resistance, increased glutathione transferases as well as enhanced DNA repair decrease the efficacy of these drugs. Research efforts continue to overcome these problems by understanding these mechanisms and by developing more effective anticancer drugs. Cyclophosphamide is one of the most widely used alkylating anticancer agents. Because of its unique activation mechanism, numerous bioreversible prodrugs of phosphoramide mustard, the active species of cyclophosphamide, have been investigated in an attempt to improve the therapeutic index. Solid tumors are particularly resistant to radiation and chemotherapy. There has been considerable interest in designing drugs selective for hypoxic environments prevalent in solid tumors. Much of the work had been centered on nitroheterocyclics that utilize nitroreductase enzyme systems for their activation. In this article, recent developments of anticancer prodrug design are described with a particular emphasis on exploitation of selective metabolic processes for their activation.  相似文献   
93.
In bioassay-guided search for inducible nitric oxide synthase (iNOS) inhibitory compounds from higher plants of South Korea, two beta-carboline alkaloids, 4-methoxy-1-vinyl-beta-carboline (1) and 4,8-dimethoxy-l-vinyl-beta-carboline (2) have been isolated from the cortex of Melia azedarach var. japonica. The structures of these compounds were elucidated on the basis of spectroscopic data. Compounds 1 and 2 showed marked inhibitory activity of iNOS on LPS- and interferon-gamma-stimulated RAW 264.7 cells.  相似文献   
94.
Two new furanolignans (3, 5), together with three known lignans (1, 2, 4), were isolated from the stem of Lindera obtusiloba (Lauraceae). The structures of the compounds were determined as actifolin (1), pluviatilol (2), 5,6-dihydroxymatairesinol (3), (+)-syringaresinol (4), and (+)-9'-O-trans-feruloyl-5,5'-dimethoxylariciresinol (5) on the basis of physicochemical and spectroscopic evidences. Compounds 1, 2, 3, and 5 showed cytotoxicity against a small panel of human tumor cell lines with ED50 values of 3.40 to approximately 19.27 microg/ml.  相似文献   
95.
Primary spinal cord primitive neuroectodermal tumor (PNET) is a rare entity. In all, 13 cases have been reported in the literature, including 3 with intracranial seeding. A 3-month-old girl with involvement of the spinal cord below the mid-thoracic level is described. The brain MRI revealed findings indicative of seeding along the intracranial subarachnoid space. Biopsy, duraplasty and removal of laminotomy flap were done. In spite of a good response to the first cycle of postoperative 8-drugs-in-a-day chemotherapy, further treatment was refused. She died 21 days after the onset of leg weakness, which reveals the rapid progression of untreated cases. To our knowledge, this is the first case of spinal cord PNET with parenchymal involvement that has been described in an infant.  相似文献   
96.
The suprathreshold tonotopic organization of rat and guineapig auditory cortex was investigated using intrinsic signaloptical imaging through a thinned skull. Optical imaging revealedthat suprathreshold pure sine wave tone stimulation (25–40dB) evoked activity over large cortical areas that were tonotopicallyorganized. Three-dimensional surface plots of the activatedareas revealed "patchy" auditory-evoked activity consistingof numerous local peaks and valleys building to a maximum. Subsequentdetailed electrophysiological mapping in the same subjects confirmedthe localization of auditory-evoked activity based on opticalimaging, including responses to a test frequency at corticalloci more than 2 octaves away from the threshold-defined isofrequencycontour. The success of this technique in visualizing auditorycortex functional organization at suprathreshold stimulus levelswill allow for future investigations of auditory cortex frequencyrepresentation. including representational plasticity inducedby a variety of experimental manipulations.  相似文献   
97.
This unusual cystic lesion was previously described as a lesion that has features of both botryoid odontogenic cyst and mucoepidermoid tumor and later was named as glandular odontogenic cyst. An additional case is reported and its clinicopathologic features described. The name "mucoepidermoid odontogenic cyst" is proposed.  相似文献   
98.
BACKGROUND: Magnetic resonance imaging studies in schizophrenia have revealed abnormalities in temporal lobe structures, including the superior temporal gyrus. More specifically, abnormalities have been reported in the posterior superior temporal gyrus, which includes the Heschl gyrus and planum temporale, the latter being an important substrate for language. However, the specificity of the Heschl gyrus and planum temporale structural abnormalities to schizophrenia vs affective psychosis, and the possible confounding roles of chronic morbidity and neuroleptic treatment, remain unclear. METHODS: Magnetic resonance images were acquired using a 1.5-T magnet from 20 first-episode (at first hospitalization) patients with schizophrenia (mean age, 27.3 years), 24 first-episode patients with manic psychosis (mean age, 23.6 years), and 22 controls (mean age, 24.5 years). There was no significant difference in age for the 3 groups. All brain images were uniformly aligned and then reformatted and resampled to yield isotropic voxels. RESULTS: Gray matter volume of the left planum temporale differed among the 3 groups. The patients with schizophrenia had significantly smaller left planum temporale volume than controls (20.0%) and patients with mania (20.0%). Heschl gyrus gray matter volume (left and right) was also reduced in patients with schizophrenia compared with controls (13.1%) and patients with bipolar mania (16.8%). CONCLUSIONS: Compared with controls and patients with bipolar manic psychosis, patients with first-episode schizophrenia showed left planum temporale gray matter volume reduction and bilateral Heschl gyrus gray matter volume reduction. These findings are similar to those reported in patients with chronic schizophrenia and suggest that such abnormalities are present at first episode and are specific to schizophrenia.  相似文献   
99.
To correct crooked nail deformity, which results from the partial loss of the distal phalanx, soft-tissue restoration alone is usually not enough to restore the length and shape of the nail structure. The authors treated 10 crooked nail fingertips by modified osteoplastic reconstruction, which included the elevation of the dorsally based volar skin flap and an iliac bone graft covered by an adequate skin flap. During the postoperative follow-up, the nail straightened, although not to the preinjury extent, along the restored distal phalanx with bony support. The authors' osteoplastic reconstruction, which involves the enhancement of the fingertips with composite tissues, presents a practical method for the correction of crooked nail deformity.  相似文献   
100.
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