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971.
Arfeen ZU Maran NJ Simon EJ McClure JH 《International Journal of Obstetric Anesthesia》1996,5(3):168-171
We compared two types of automatic non-invasive blood pressure measuring device with sphygmomanometey in 47 normotensive and 38 hypertensive women in the third trimester of pregnancy. An automatic oscillometric device (Accutor) and a volume-clamp device (Finapres) significantly underestimated the diastolic pressure as measured by the fourth Korotkoff sound using a Hawksley random zero sphygmomanometer. The mean difference between the sphygmomanometer and Accutor measurement of diastolic blood pressure was +3.1 mmHg in the normotensive women and +8.3 mmHg in the hypertensive women (P = 0.001). The mean difference between the sphygmomanometer and Finapres measurement of diastolic blood pressure was +6.1 mmHg in the normotensive women and +11.5 mmHg in hypertensive women (P = 0.003). The increased use of continuous non-invasive devices to monitor blood pressure in women with hypertension should be accompanied by sound knowledge of their limitations in this group of patients. 相似文献
972.
Genetic manipulation of mammary epithelium by transplantation 总被引:2,自引:0,他引:2
Genes can be introduced into mammary epitheliumin vivo by the tissue reconstitution method. Primary cultures of mammary epithelial cells are prepared, a gene introduced using retrovirus vectors, and the cells transplanted into a mammary fat pad from which the normal epithelium has been removed. The cells reform an epithelium in which some cells express the introduced gene. The technique is reviewed and compared with the mammary-specific expression of genes in transgenic mice. To model the development of neoplasia, particularly the preneoplastic changes caused by a single oncogene alone, several oncogenes have been expressed this way—myc, Ha-ras, erbB, erbB2,Wnt-1, andhst/FGF-4. Each caused a different alteration to the growth pattern of the epithelium, such as altered branching, premature alveolus development, distorted duct structure, or altered hormone sensitivity. Insights into normal development have also been obtained by inappropriate expression of genes such asWnt-4. 相似文献
973.
Paul M. Gross Richard J. Beninger Steven W. Shaver Dan S. Wainman Francisco J. Espinosa Donald F. Weaver 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1993,95(3):397-408
The neuroactive peptide endothelin-1 has receptors distributed abundantly among subdivisions and nuclei of the visuovestibular and oculomotor systems. In previous work, we and others described the convulsive manifestations resulting from central injection of this neuropeptide, including nystagmus, oculoclonus, exophthalmos, tonic hindlimb extension, and a generalized repetitive motor disturbance called barrel-rolling. We applied the quantitative, autoradiographic [14C]deoxy-glucose method to examine the hypothesis that visuovestibular and oculomotor structures would become metabolically stimulated when endothelin was introduced into the brain via the ventricular system in conscious rats. Since previous work had demonstrated that hypermetabolic responses to endothelin in other neural systems were inhibited by an antagonist of neuronal calcium L-type channels, nimodipine, we further tested whether the increased function of vestibulooculomotor nuclei whose metabolic activity was sensitive to endothelin could be altered following nimodipine pretreatment via the ventricle. A single unilateral injection of endothelin (9 pmol in 3 l saline) into a lateral ventricle provoked significantly increased rates of glucose metabolism in 22 of 39 individual anatomical structures of the visuovestibular and oculomotor systems. Among those affected were the superficial stratum of the caudal superior colliculus (+25%), the optic tract bilaterally (+ 35 to 43%), the oculomotor cranial nerve nuclei (III, IV, VI; range of +21 to 47%), and the medial terminal nucleus of the accessory optic tract which harbors dense fields of endothelin binding sites (bilateral increase of +70 to 96%). Several other nuclei involved in the proprioceptive and visuovestibular disturbance caused by endothelin displayed increased metabolic activity, including the cuneate, gracile, sensory trigeminal, and prepositus hypoglossal nuclei, the vestibular subnuclear system, and the cerebellar flocculus. Identification of hypermetabolic responsivity to endothelin in these structures provides further information on the anatomical substrates mediating the behavioral phenomenology of endothelin-induced motor convulsions which involve the paroxysmal participation of the extraocular muscles and motor control systems producing barrel-rolling convulsions. Nimodipine pretreatment inhibited both the convulsive activity and the cerebral hypermetabolic responses to intraventricular endothelin. The results indicate that the neural systems sensitive to intraventricular endothelin become functionally active via a calcium-mediated process that may involve the neuropeptide as an intrinsic signaling molecule. 相似文献
974.
975.
Arne Simon Roland A. Ammann Anja Wilkesmann Anna M. Eis-Hübinger Oliver Schildgen et al. 《Infection》1993,21(1):39-39
Information
The 11th Meeting of the European Society for Paediatric Infectious Diseases (ESPID) 26–28 May 1993 Helsinki, Finland 相似文献976.
We reviewed consecutive patients (n = 12) at McLean Hospital from 1990 through 1991 treated with the combination of the atypical antipsychotic agent clozapine and electroconvulsive therapy (ECT). There were no adverse effects. Three patients had a marked clinical improvement, one a moderate response, four a minimal response, two minimal to no response, and two no response. Using daily doses of up to 550 mg clozapine, this combination appears to be safe, and may be useful in some patients with treatment-refractory psychosis. 相似文献
977.
Summary An oral dose of 0.5 mg/kg/day malathion continuously administered for one year has been investigated to produce no change in biochemical (RChE, PChE, aspartate-and alanine aminotransferases, blood glucose, serum urea and plasma total proteins) or haematological (Hb, PCV, tRBC and tWBC) parameters and, therefore, considered to be no-effect-level inBubalus bubalis. However, the administration of higher doses (1.0 and 1.5 mg/kg/day) produced significant (P<0.05) changes in all biochemical parameters studied. With these doses leucocytosis was evident among haematological parameters measured. 相似文献
978.
Paul H. Soloff M.D. 《Archives of sexual behavior》1978,7(5):503-510
The emergence of homosexual anxieties in heterosexual males following a severe blow to masculine self-esteem has been termed pseudohomosexual by Ovesey and has been shown to reflect sexual dependency and power conflicts. This article extends the concept, described largely in neurotic patients, to psychotic reactions occurring in basic trainees following failure to adapt to military life. The military setting is viewed as a culturally specific stress for emergence of pseudohomosexual anxieties in predisposed individuals. Case studies illustrate the power and dependency conflicts, sexual symbolization, projective defenses, and restitutional violence which characterize these patients. The pseudohomosexual psychosis defends the patient against perceiving his inability to effect separation from mother, bear the object loss, and attain cultural manhood.The views presented represent those of the author and are not to be interpreted as representing the Department of Defense or the U.S. Air Force. 相似文献
979.
Pentose shunt activity in developing chick retina and pigment epithelium was studied by measuring the rate of 14CO2 evolution from glucose selectively labelled in the C-1 and C-6 positions. In the retina, shunt activity declines from appreciable levels at stages 29–31 to minimal activity in the 2-week-old hatched chick. Overall retinal metabolism also declines up to stage 45, but dramatically increases again after hatching. Developing chick pigment epithelium has minimal shunt activity at all stages studied. In contrast, cultured chick pigment epithelium has appreciable shunt activity which is constant over a period of several weeks in culture. This appears to be a switch in biochemical differentiation which could form the basis at least in part for subsequent changes in cell types observed in cultured pigment epithelial cells byEguchi and Okada (1973). 相似文献
980.
John J. Gullo Charles L. Litterst Patrick J. Maguire Branimir I. Sikic Daniel F. Hoth Paul V. Woolley 《Cancer chemotherapy and pharmacology》1980,5(1):21-26
Summary The pharmacokinetics of cis-dichlorodiamminoplatinum (II) (cisplatin) have been studied in seven patients, of whom four received the drug as a one hour infusion and three received it as a 20 h infusion. The patients receiving the drug over one hour exhibited biphasic clearance of total platinum with a rapid initial phase (8.7–22.5 min) and a prolonged second phase (30.5–106 h). Free (ultrafilterable) cisplatin was readily detectable in this group and was rapidly cleared (half-life about 22 min). The volume of distribution of the drug was 50.3–65.6 liters and it was 26.6–50% excreted in the urine in 48h. In the patients receiving the 20 h infusion, a more complex plasma elimination curve was seen, with the appearance of a secondary peak. Free drug was not detectable in these patients and they showed less urinary excretion (21.4–25.9% at 48 h) than the one hour group. Cisplatin was bound to several plasma proteins, including albumin, transferrin, and -globulin. The data indicate that cisplatin is retained in the body more extensively after a 20 h infusion than after a one hour infusion. 相似文献