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941.
L P Dimnikova 《Neirofiziologiia》1991,23(5):574-579
Impulse activity of the anterior and posterior hypothalamus neurons was investigated in the unanaesthetised and anaesthetised (urethan and chloralose) rabbits. Anaesthesia is shown to induce a decrease of the mean firing rate, alteration of the impulse activity pattern and a decrease of the quantity of neurons, responding to the skin thermal stimulation. These changes are expressed most of all in the posterior hypothalamic neurons. 相似文献
942.
Changes in women's mental and physical health from pregnancy through six months postpartum 总被引:1,自引:0,他引:1
A longitudinal study was conducted to investigate changes in women's mental and physical health around the time of childbirth, and to determine whether health was related to length of maternity leave. Thirty-seven married, employed first-time mothers completed questionnaires during pregnancy, and again at 6 weeks, 3 months, and 6 months postpartum. Results showed that, from pregnancy to the 6th postpartum month, the number of days that mothers were ill because of infections steadily increased. In addition, depressive symptoms for new mothers rose from pregnancy to the 6th week postpartum, and declined thereafter. For women who did not return to work during the period of the study, a significant decline in depressive symptoms was observed from the prenatal period through the 6th postpartum month. These findings demonstrate significant changes in mental and physical health for this group of first-time mothers. 相似文献
943.
Human exposure to 3-carene by inhalation: toxicokinetics, effects on pulmonary function and occurrence of irritative and CNS symptoms 总被引:5,自引:0,他引:5
Terpenes, especially 3-carene, may irritate the skin and mucous membranes and prolonged exposure may result in allergic contact dermatitis or chronic lung function impairment. The toxicokinetics of 3-carene were studied in human volunteers exposed by inhalation (2 hr 50 W) in an exposure chamber on three occasions. The exposure concentrations were approximately 10, 225, and 450 mg/m3 3-carene. The relative pulmonary uptake was high, approximately 70% for the higher exposure levels. Total uptake increased linearly with increasing exposure. The blood clearance of 3-carene observed in this study, 0.9 liter.kg-1.hr-1, indicates that 3-carene is fairly readily metabolized. About 3% of the total uptake was eliminated unchanged via the lungs while less than 0.001% was eliminated in the urine after the end of exposure. A long half time in blood was observed in the terminal phase which indicates a high affinity to adipose tissues. A statistically significant divergence between ratings of irritation during the high exposure level and during the medium and control levels was observed. The difference in airway resistance after exposure to a high concentration of 3-carene compared to control level was not significant (P = 0.02). 相似文献
944.
A McRae S Hjorth D W Mason L Dillon T R Tice 《Journal of neural transplantation & plasticity》1991,2(3-4):165-173
Biodegradable controlled-release microsphere systems made with the biocompatible biodegradable polyester excipient poly [DL lactide-co-glycolide] constitute an exciting new technology for drug delivery to the central nervous system (CNS). The present study describes functional observations indicating that implantation of dopamine (DA) microspheres encapsulated within two different polymer excipients into denervated-striatal tissue assures a prolonged release of the transmitter in vivo. Moreover, in this regard, the results show that there were clear cut temporal differences in the effect of the two DA microsphere formulations compared in this study, probably reflecting variations in the actual composition (i.e., lactide to glycolide ratio) of the two copolymer excipients examined. This technology has considerable potential for basic research with possible clinical application. 相似文献
945.
B T Hyman J E Flory S E Arnold G W Van Hoesen R L Schelper H Ghanbari H Haigler 《Journal of geriatric psychiatry and neurology》1991,4(4):231-235
A quantitative assay for ALZ-50 immunoreactivity was evaluated in samples of superior temporal gyrus taken at autopsy from 13 Alzheimer patients and 11 controls. The assayable immunoreactivity appears to be stable for at least 24 hours postmortem but was lost with formalin fixation. The mean value of the Alzheimer patients was tenfold higher than that of the controls (P less than .002). The values of four Alzheimer samples overlapped with the low levels seen in controls, but no controls had elevated levels. In this sample population, therefore, the assay had a sensitivity of 69% and specificity of 100%. 相似文献
946.
M L Chindia S W Guthua D L Mwaniki 《International journal of oral and maxillofacial surgery》1991,20(2):73-74
A case of an ameloblastoma diagnosed about 3 1/2 years after removal of an impacted mandibular 3rd molar is presented. The pre-operative radiographs, though poor in quality, showed an ill-defined radiolucency in relation to the tooth. This feature was not apparent to the examiners at the time of first presentation. Despite unfavourable working conditions in developing countries, a high level of suspicion should be maintained to avoid serious sequelae at a later stage. 相似文献
947.
948.
Daptomycin (LY146032) caused a calcium-dependent dissipation of the membrane potential (delta psi) in Staphylococcus aureus without noticeably affecting the chemical gradient (delta pH) across the membrane. The effect of daptomycin on membrane energization may account for many of the inhibitory effects on macromolecular biosyntheses and membrane function reported for this antibiotic. Our evidence indicates that the bactericidal activity of daptomycin is dependent on an available delta psi. 相似文献
949.
950.
Single or combined monoclonal antibodies (McAbs) Zh53, Zh820, and Zh2-1 have been used to eliminate malignant clonogenic cells from human bone marrow. The test of cytotoxicity showed that all of these McAbs could express high specific cytotoxic action against HL-60 cells and were selectively complement-dependent cytotoxic to various types of fresh leukemic cells. Clonogenic assay detected that single treatment with antibody and rabbit complement (RC) could reduce clonogenic units of HL-60 cells by more than 2 logs and two treatments reduced clonogenic units by more than 4 logs. However, combination of 2 McAbs could reduce clonogenic units by 4-5 logs. The data suggest that multiple treatments with McAbs and RC or a combination of 2 McAbs are more effective than a single treatment in eliminating clonogenic tumor cells. Treatment of normal human bone marrow with Zh53, Zh2-1 and RC did not produce a loss of normal CFU-GM, but treatment with Zh820 reduced the clonic units of normal CFU-GM by 24%.
相似文献