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981.
982.
Biting and scratching behaviors produced by intrathecal injection of excitatory amino acid (EAA) agonists were examined to determine whether the biting and scratching behavioral effects produced by these compounds are altered selectively in vivo by coadministration with divalent cations. N-methyl-D-aspartate (NMDA)-induced behavior was inhibited by both magnesium and calcium but not by zinc. Kainic acid (KA)-induced behavioral activity was also inhibited by coadministration with calcium but not by magnesium or zinc. In contrast to both NMDA and KA, calcium, magnesium and zinc failed to alter the intensity of quisqualic acid (Quis)-induced biting and scratching behaviors. Based on this selective inhibition of the three EAA subtypes by divalent cations, we examined the behavioral responses produced by Glu and Asp in combination with calcium or magnesium to identify the receptor population involved in these motor effects. Calcium antagonized the biting and scratching behavior produced by i.t. injected Glu in contrast with Asp which was inhibited significantly by magnesium. Our results support the concept that Glu and Asp produce biting and scratching behaviors by an interaction with distinct receptor populations in the spinal cord. To date, there are no selective antagonists at the KA or Quis receptors. Thus, a systematic examination of the selective inhibition of EAA activity by divalent cations in addition to currently available pharmacologic antagonists may prove to be a useful approach to the identification of NMDA, KA and Quis receptor interactions.  相似文献   
983.
In a phase I-II study, 21 patients with relapsed or refractory acute leukemia were treated with 4'-deoxydoxorubicin (esorubicin), the 4'-deoxy derivative of doxorubicin. Four of 14 evaluable patients with acute nonlymphocytic leukemia (ANLL) in relapse or refractory to other anthracyclines achieved partial response (28.5%). Pharmacokinetics were similar to those of the parent compound, doxorubicin. Esorubicin has activity in ANLL and has pharmacologic properties comparable to those of other anthracyclines. Dose-limiting toxicity occurs in the form of mucositis, which may limit its use in combination with other antileukemic drugs.  相似文献   
984.
985.
986.
A digital test of pelvic muscle strength for evaluation of a pelvic muscle exercise (PME) program was developed with a sample of 338 incontinent women living at home. Factors of perceived pressure, alteration of the vertical plane, and time were combined to form a 7-point scale ranging from 0 to 4. Test-retest for the anteroposterior score was r = .65, p less than .01 with interrater reliability, r = .91, p less than .01. Relationship to other variables and further development of the measure are discussed.  相似文献   
987.
Seventeen patients who had undergone extensive small bowel resection were studied for calcium absorption (FACa) and plasma vitamin D metabolites. FACa was measured by a double radio-tracer technique and expressed as percentage of total oral dose. FACa was decreased compared with controls (34%, range: 3-46 v 65%, range: 57-73, P less than 0.01). A positive correlation (r = 0.49, P = 0.05) was found between FACa and the remaining length of small bowel (SBL). As wide variations in both SBL and duration after surgery were observed among the seventeen investigated patients, we were led to individualize less heterogeneous subgroups of patients. Better correlations were found when the patients were divided into two subgroups according to whether the time interval between the resection and the investigation was shorter (r = 0.75, n = 11, P less than 0.02) or longer (r = 0.89, n = 6, P = 0.05) than 2 years. In thirteen patients who had a SBL shorter than 100 cm, a positive correlation was observed between FACa and the time interval after surgery (months): r = 0.65, P less than 0.05. Plasma 1,25 (OH)2D was markedly reduced in the whole group (31 pmol l-1, range: 8-108) compared with controls (103 pmol-1, range: 59-134, P less than 0.01). The present study shows that in extensively small bowel resected patients, calcium absorption is reduced, the alteration being dependent both on the length of the remnant small bowel and on the time after surgery.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
988.
989.
The endosteal hollow cylinder implant systems have been in clinical use for over 10 years. These systems incorporate advanced sophisticated biomaterials and bioengineering design concepts such as the titanium plasma spray (TPS) surface coating as well as the cylindric shape. This shape has now introduced the third dimension to dental implantology. In previous systems, such as the blade-vent, only height and width were present. Therefore, these previous systems could not be used as single-tooth replacements; also, they were not able to withstand lateral forces or torquing. In a series of cases reported from Switzerland, Sweden, Germany, and the United States, 580 hollow cylinder implants were placed for up to 10 years with an overall rate of success of 95.3 per cent.  相似文献   
990.
A lawsuit directed by parents at a day care program following an outbreak of infectious disease would most likely be based on the legal theory of negligence--the failure to exercise due care as required by circumstances. In the determination of liability for infectious diseases in child day care, the element of causation is most critical. Did the day care facility's actions or failure to act cause the harm? Another important question is whether an infectious disease can be occupational and under what circumstances. Although worker's compensation laws initially had no provisions for occupational disease, now all states recognize responsibility for them. Awareness of potential problems with legal liability and establishment of procedures to minimize risk are important for day care providers, public health officials, clinicians, and parents.  相似文献   
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