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101.
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Morpholinoalkyl esters (HCl salts) of naproxen 1 and indomethacin 3 were synthesized and evaluated in vitro and in vivo for their potential use as prodrugs for oral delivery. Prodrugs were freely soluble in simulated gastric fluid (SGF) and pH 7.4 phosphate buffer and showed a minimum of a 2000-fold increase in solubility over the parent drugs. All prodrugs were more lipophilic than parent drugs as indicated by n-octanol/pH 7.4 buffer partition coefficients but less lipophilic in terms of n-octanol/SGF partition coefficients. Potentiometrically determined pKa's for prodrugs were in the range of 6.89 to 8.62 at 25 degrees C. All prodrugs were quantitatively hydrolyzed to their respective parent drugs by enzymatic and/or by chemical means. An increase in carbon chain length rendered the prodrugs more stable at pH 7.4 but less stable in SGF. The esters were generally found to be hydrolyzed rapidly in rat plasma at 37 degrees C, the half-lives being in the range of 1.2-31.0 min. Based on in vitro results, prodrugs 2c and 4c were chosen to evaluate solid-state stability, in vivo bioavailability, and ulcerogenicity. At elevated temperatures, the solid-state decomposition of 2c and 4c followed biphasic kinetics, with rapid decomposition occurring initially. The prodrugs were 30-36% more bioavailable orally than the parent drugs following a single equimolar solution dose in rats. Prodrugs 2c and 4c were significantly less irritating to gastric mucosa than parent drugs following single-dose and chronic oral administration in rats.  相似文献   
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We investigated the effect of the somatosensory functions to the outcomes of motor functions in 28 patients with thalamic hemorrhage. The disturbance of the pyramidal tracts was assessed by the destruction of the internal capsule found in computed tomography (CT). The disturbance of the somatosensory function was analyzed by the N20 component of short-latency somatosensory evoked potentials (SSEP). The outcomes of motor function was evaluated after 3 months of ictus. Correlations between the outcomes of motor function, disturbance of the pyramidal tract, and disturbance of the somatosensory function were discussed. The result indicated that functional outcomes statistically correlated with neither disturbance of the internal capsule alone nor disturbance of N20 alone. But, there was statistically significant between functional outcomes and the combination of disturbance of the internal capsule with disturbance of N20 (p < 0.05, Wilcoxon signed-rank). There was not statistical difference in hematoma volume or consciousness. The implications of these results suggest that somatosensory function may affect the recovery of motor functions.  相似文献   
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Mechanical testing of the spine can be carried out in either a load-controlled or a displacement-controlled manner. Each method requires certain assumptions and offers different advantages. Dr. W. Thomas Edwards believes that displacement-controlled testing most accurately reflects the in vivo environment, while Drs. Vijay Goel, David Wilder, and Malcolm Pope support the use of the load-controlled method as most logical and easily standardized.  相似文献   
108.
In the department of microsurgery of A.A. Vishnevsky Central Hospital the transplantation and transposition of the at the gunshot injuries of the extremities have begun to execute since 1990. For this time 94 surgical interventions have been conducted at 88 wounded: 57 transplantations and 37 transpositions of the bloody tissues. The transplantation and transposition of the vascularized complexes of tissues with application of microsurgical technique is the effective method of the treatment of the wounded in the extremities. In the conditions of the local armed conflicts it is necessary to provide deployment of the department of microsurgery at stages of the specialized medical care.  相似文献   
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Local hyperthermia and the hypoxic cytotoxin SR 4233 were administered to nude mice with 693 +/- 47 mm3 (mean +/- SE) s.c. HCT-8 human colonic adenocarcinoma xenografts in an attempt to enhance the antitumor effects of radioimmunotherapy. Biodistribution studies revealed preferential binding of NR-Lu-10, a murine monoclonal antibody, to the tumors compared with an isotype-matched control antibody, CCOO16-3.A single injection of 25 microCi 90Y-NR-Lu-10 significantly inhibited tumor growth (control versus 90Y-NR-Lu-10: P = 0.048). The administration of hyperthermia at 41.5 degrees C for 1 h immediately following the injection of 111In-labeled NR-Lu-10 up-regulated tumor-associated antigen expression and increased antibody uptake in the tumors by 73% (P = 0.001) without significantly affecting antibody uptake in normal tissues. However, the heat treatment did not produce a more homogeneous distribution of the antibodies in the tumors and did not significantly enhance the tumor growth delay produced by 90Y-NR-Lu-10 (P = 0.07). The administration of local hyperthermia at 43.0 degrees C for 1 h, on the other hand, had direct cytotoxic effects (P = 0.03) and enhanced the tumor growth delay produced by 90Y-NR-Lu-10 (P = 0.01). SR 4233 also enhanced the tumor growth delay produced by 90Y-NR-Lu-10 (P = 0.03). The greatest antitumor effects were observed when both hyperthermia at 43.0 degrees C and SR 4233 were administered in combination with 90Y-NR-Lu-10 (P = 0.002). No toxicity was produced by the local hyperthermia, and the only toxicities produced by 90Y-NR-Lu-10 and SR 4233 were neutropenia and weight loss.  相似文献   
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