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31.
Few investigations have looked at behavioral stress outcomes in Alzheimer's caregivers. This study documented concentration deficits to examine behavioral outcomes of stress in 33 Alzheimer's Disease (AD) caregivers and in 33 age-, sex-, and race-matched controls. As hypothesized, caregivers showed less persistence than controls in solving problems from a standard test of problem-solving ability. In addition, caregivers tended to make more errors than controls on a standard proofreading task ( p < .09). In AD caregivers, cognitive deficits (represented by lower scores on problem-solving and concentration tasks) may be representative of a broader deficit in concentration that impairs the ability of caregivers to provide for their own needs and the needs of the family member for whom they are caring.  相似文献   
32.
Summary: Amphiphilic polysaccharides are obtained by hydrophobic modification of a neutral bacterial polysaccharide, dextran. By reacting the polysaccharide with aliphatic epoxides (epoxyoctane and epoxydodecane) in dimethyl sulfoxide, a series of amphiphilic polymers is obtained which covers a large range of structural parameters (length of the polysaccharide, number and nature of hydrocarbon moieties). The solution behavior of dextran derivatives is first characterized by viscometric measurements in dilute and semi‐dilute domains. The effects of molecular parameters on polymer viscosity behavior are evidenced and discussed. Information on the state of aggregation of polymers is obtained by the use of static and dynamic light scattering. The presence of aggregates in the dilute domain is clearly evidenced and their structural characteristics are estimated (size, molecular weight and number of aggregation). The aggregates are shown to account for the viscometric results in the examined concentration range, relating their chemical parameters (hydrodynamic radius and molecular weight) to the macroscopic behavior of the solutions.

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33.
Summary Vaccinia virus recombinants were constructed which contained cDNA sequences encoding the structural region of dengue 2 virus (PR159/S1 strain) or yellow fever virus (17D strain). The flavivirus cDNA sequences were expressed under the control of the vaccinia 7.5k early/late promotor. Cultured cells infected with these recombinants expressed immunologically reactive flavivirus structural proteins, precursor prM and E. These proteins appeared to be cleaved and glycosylated properly since they comigrated with the authentic proteins from dengue 2 virus- and yellow fever virus-infected cells. Mice immunized with the dengue/vaccinia recombinant showed a dengue-specific immune response that included low levels of neutralizing antibodies. Immunization of mice with the yellow fever/vaccinia recombinant was less effective at inducing an immune response to yellow fever virus and in only some of the mice were low titers of neutralizing antibodies produced.  相似文献   
34.
Coupling of anthracyclines to high-molecular-weight carriers may alter drug disposition and improve antitumor effects. We have performed a clinical phase I trial of doxorubicin coupled to dextran (70000 m.w.). The drug was administered as single dose i.v. every 21–28 days. Thirteen patients have received a total of 24 courses (median 2; range 1–3). At the starting dose of 40 mg/m2 doxorubicin equivalent (DOXeq), WHO grade IV thrombocytopenia was noted in 2/2 patients. WHO grade IV hepatotoxicity and WHO grade III cardiotoxicity were noted in a patient with preexisting heart disease. Five patients were treated with 12.5 mg/m2 DOXeq. Maximal toxicity at this dose level was WHO grade III thrombocytopenia and local phlebitis (WHO grade II) in 1/5 patients, elevation of alkaline phosphatase (WHO grade III) and WHO grade III vomiting in another patient. Subsequently, five patients received 20 mg/m2 DOXeq. Hepatotoxicity was noted in 5/5 patients (1 × WHO grade IV, 1 × WHO grade III). Thrombocytopenia was noted in 3/5 patients (1 × WHO grade IV, 2 × WHO grade III). At 12.5 mg/m2 DOXeq, a patient diagnosed with a malignant fibrous histiocytoma had stable disease for 4 months. Pharmacokinetic analyses of total and free doxorubicin were performed in plasma and urine. The maximum peak plasma concentration (ppc) for total DOX was 12.3 g/ml at 40 mg/m2 DOXeq. The area under the plasma concentration time curve (AUC) ranged from 28.83–80.21 g/ml*h with dose-dependent elimination half lives (t1/2: 0.02–0.87 h;1/2: 2.69–11.58 h;1/2: 41.44–136.58 h). We conclude that the maximal tolerated dose (MTD) of AD-70 using this schedule is 40 mg/m2 DOXeq. The recommended dose for clinical phase II studies is 12.5 mg/m2 DOXeq.Abbreviations ALT Alanine Aminotransferase - AST Aspartate Aminotransferase - DOX Doxorubicin - DOXeq Doxorubicin Equivalent - ECG Electrocardiogram - HPLC High Pressure Liquid Chromatography - LD10 Lethal Dose for 10% of individuals - MTD Maximal Tolerated Dose - ppc Peak Plasma Concentration - WHO World Health Organisation  相似文献   
35.
  1. The effects of zidovudine (ZDV) and zidovudine triphosphate (ZDV-3P) on Ca2+-induced mitochondrial permeability transition (MPT), respiratory control ratio (RCR) and ATP synthesis have been investigated on isolated rat liver mitochondria.
  2. ZDV slightly but significantly decreased RCR and ATP synthesis but was ineffective in inhibiting MPT. In contrast, ZDV-3P did not alter RCR and ATP synthesis but strongly inhibited MPT (IC50=3.0±0.9 μM).
  3. The effect of ZDV-3P on mitochondrial swelling required a preincubation time. When incubated 10 min with mitochondria, ZDV-3P (8 μM) totally inhibited the rate of swelling.
  4. ADP, ATP and atractyloside, which are agents known to interact with the mitochondrial adenine nucleotide carrier (ANC), antagonized the effect of ZDV-3P on mitochondrial swelling. Indeed, the IC50 value of ZDV-3P increased from 3.0 to 17.4, 93.6 and 66.5 μM, in the presence of 20 μM, ADP, ATP or atractyloside, respectively.
  5. ZDV-3P did not displace [3H]-ATP from its mitochondrial binding site(s) whereas ADP and atractyloside did, suggesting that ZDV-3P and [3H]-ATP do not share the same binding sites.
  6. ZDV-3P did not affect either mitochondrial respiration or ATP synthesis but inhibited Ca2+-dependent mitochondrial swelling. It was concluded that mitochondrial toxic effects observed during the chronic administration of ZDV cannot be related to its active metabolite (ZDV-3P).
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36.
The Chamorro population of the island of Guam is highly susceptible to a disease called lytico-bodig (LB), wich clinically resembles a mixture of amyotrophic lateral sclerosis (ALS), Parkinson's disease (PD) and Alzheimer disease (AD). The disease is characterized by the widespread development of neurofibrillary tangles in the central nervous system. These tangles have an immuno-histochemical profile indistinguishable from that seen in AD. We studied by immunohistochemistry the occurrence of intracellular and extracellular neurofibrillary tangles in LB in the entorhinal cortex, hippocampus and substantia nigra using antibodies to tau protein and ubiquitin. We also studied the relationship of these tangles to amyloid precursor protein (APP) and its -amyloid fragment (BAP), using multiple antibodies to BAP and other APP sequences. In advanced cases of LB, the development of neurofibrillary tangles was far more severe than in advanced cases of AD. Virtually all neurons of CA-1 and the subiculum were lost and only ghost tangles remained. In areas dominated by such extracellular tangles, BAP deposits were frequently observed developing around the fibers of ghost tangles. In some cases, the deposits covered only a few of the fibers, but in others, they seemed to envelope the complete tangle. The deposits were thiolavin S and Congo red positive, indicating that the BAP was in a consolidated form. We describe these entities as tangle-associated amyloid deposits. Such BAP deposits have previously eeen described in some cases of AD, dementia pugilistica and LB. However, we found them in all cases of LB with dementia in the hippocampal-entorhinal areas and in most cases in the substantia nigra. They do not evolve from diffuse BAP deposits since they are remote from them, and they do not trap dystrophic neurites. The fact that extracellular tangle material can act as a nidus for BAP build-up in LB suggests that further consideration needs to be given to the ways in which extracellular BAP deposits are formed.  相似文献   
37.
PURPOSE OF THE PAPER: This study provides baseline information on the characteristics of Native Hawaiian mothers and the health status of their infants, comparing residents of Hawaii with those of the continental U.S. The impact of Hawaii residence on low birth weight and infant mortality among Native Hawaiians is assessed. SUMMARY OF METHODS UTILIZED: Data from the National Center for Health Statistics 1983­1987 Linked U.S. Live Birth and Infant Death file were used to examine parental characteristics, prenatal care use and infant outcomes using chi­square and logistic regression procedures. PRINCIPAL FINDINGS: Despite a higher sociodemographic risk profile among Hawaii resident mothers, preterm birth, low and very low birth weight percentages were similar. Continental infants had significantly highter percentages of very pre­term birth and macrosomia. Mortality rates in both the neonatal and post­neonatal periods, and for SIDS and perinatal causes were elevated among continental infants. Hawaii residence had a borderline protective effect on infant mortality, wehn sociodemographic and prenatal care differences were controlled. CONCLUSIONS: This study suggests a possibly protective effect of Hawaii residence on the health of Native Hawaiian infants during the period of following employer­mandated health insurance coverage but before the initiation of "gap­group" coverage and the Native Hawaiian Health Care Systems in Hawaii. RELEVANCE TO ASIAN PACIFIC ISLANDER AMERICAN POPULATIONS. This is the first report documenting the sociodemographic and health status of the growing number of Native Hawaiian mothers and their infants residing outside of Hawaii. Expanded health insurance coverage and culturally appropriate and accessible health care may contribute to improved infant health status in Hawaii. Their absence, along with possible barriers of sociocultural isolation, may account for the poorer than expected outcomes of continental infants and predict a widening gap between them and their counterparts in Hawaii. A follow­up study of the health status of Native Hawaiian mothers and infants, and their access to appropriate care in Hawaii and thei continental U.S. is recommended.  相似文献   
38.
Summary In the first part the case of a then 27 year old female patient with right-sided infantile spastic hemiplegia after left-sided porencephaly is described, in whom hemispherectomy was performed 25 years ago. The postoperative state and the development are described as well as the social outcome and the present neurological status. A computer-tomogram shows the actual state of the brain.The second part is devoted to a scientific discussion of the supplementary motility after pyramidal lesions which is defined as the action of descending subcortico-spinal pathways starting probably in the mesencephalon, whereas an ipsilateral pathway is unlikely. Comparative neurological experiments serve to support such a concept as well as similar observations in traumatic cerebral lesions in man. In the light of the far more skilled motility in cerebral lesions of the young as well as the possibility of a shift of neuropsychological functions of the dominant to the contralateral hemisphere in children up to the age of 8–10 the possibility is discussed that plasticity — the concept of Albert Bethe — could form the mechanism of auxiliary function.Furthermore the surprising sensory performances in some of the patients with hemispherectomy are emphasized and the possibilities of anipsilateral substratum are discussed; however, this contrasts with the concepts formulated for the auxiliary motility after pyramidal lesions. Clarification of these problems will probably follow only after further experimental work.
Zusammenfassung Im ersten Teil der Arbeit wird der Fall einer damals 27-jährigen Patientin beschrieben, die eine rechtsseitige infantile spastische Hemiplegie nach linksseitiger Porencephalie hatte. Bei ihr war 25 Jahre zuvor eine Hemisphärektomie durchgeführt worden. Der postoperative klinische Status und die Entwicklung der Syndrome wird beschrieben und über die soziale Situation berichtet. Schließlich wird der derzeitige neurologische Status genau wiedergegeben. Erstmalig zeigt ein Computer-Tomogramm den Zustand des Hirns nach diesem Zeitraum.Im zweiten Teil der Arbeit wird die Entstehung der Ersatz-Motilität diskutiert, die als eine Aktion deszendierender subkortiko-spinaler Bahnen definiert wird, die wahrscheinlich vom Mittelhirn ihren Ausgang nehmen, während die Tätigkeit ipsilateraler Systeme für unwahrscheinlich gehalten wird. Vergleichende Tierexperimente am Hirn unterstützen eine solche Auffassung, ebenso wie auch die Beobachtung bei umschriebenen Hirnverletzungen des Menschen.Dann wird die Möglichkeit von Ersatzfunktionen durch Plastizität diskutiert — ein Begriff von Albert Bethe. Dies erscheint im Lichte vieler Beobachtungen wichtig, da die Ersatz-Motilität bei Hirnläsionen junger Menschen sehr viel höhere Geschicklichkeit ermöglicht als bei Läsionen von Älteren; weiter ist zu beachten, daß neuropsychologische Funktionen bei einer Hirnläsion vor dem 8. bis 10. Lebensjahr von einer dominanten Hemisphäre noch auf die andere Seite verlegt und dort lokalisiert werden können. Schließlich wird bei diesen Patienten auf die erstaunlichen Fähigkeiten der sensiblen Systeme nach Hemisphärektomie hingewiesen und hier die Möglichkeit eines ipsilateralen anatomischen Apparates diskutiert. Jedoch können bei der Sensibilität so genaue funktionell-morphologische Vorstellungen noch nicht formuliert werden, wie sie sich z. Zt. schon für die Ersatz-Motilität nach Pyramidenbahnläsion ergeben. Erst genauere Experimente im Tierversuch können weitere Aufklärung bringen.
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39.
We report four patients (three male, one female) with septo-optic dysplasia and growth hormone deficiency. All had GH therapy for a period of four to eight years until reaching final height. In all four cases bone maturation during puberty was accelerated (1.4 to 1.9 "years"/year), resulting in a final height which was clearly below the predicted height. The progress of pubertal stages was very short in all patients. In three patients TSH and prolactin release after TRH stimulation were increased. These data support a hypothalamic original of the endocrine disorder. Insufficient GH release, even after repeated GHRH stimulation, is in contrast to this assumption. In one case there was a late manifestation of neurohormonal diabetes insipidus, which indicates the possibility of later disease progression. MR imaging of the brain demonstrated variable malformation of the septum pellucidum, chiasma and nervus opticus or the pituitary gland, respectively.  相似文献   
40.
Summary The normal flora of the intestinal tract, mainly consisting of anaerobic bacteria, protects the host against colonization by pathogenic microorganisms. Antimicrobial treatment with ceftriaxone may influence the colonic microflora and as a consequence, the protective effect. Ten healthy volunteers received 1 g of ceftriaxone intramuscularly for five days. This resulted in a significant decrease (p<0.05) of the mean cultural counts (± SEM) of total anaerobes from 10.67 (0.11) (prior to treatment) to 9.02 (0.45) and 8.97 (0.46) at days 3 and 5, respectively (during treatment). After treatment (days 10 and 15–19), the cultural counts of anaerobes returned to 10.17 (0.16) and 10.44 (0.18), respectively. Bacterial enzymes may serve as an indicator of protective microflora. - aspartylpeptidase and deoxycholate hydrolase activity was determined in faecal supernatants of the volunteers and compared with anaerobic culturing. Both enzymatic activities show a significant correlation with the total number of anaerobes present at day 3 of ceftriaxone treatment. At day 5 and 8 only -aspartylpeptidase showed significant correlations with cultural counts of total anaerobes,Bacteroides spp. or bifidobacteria. At day 15 to 19 (ten to 14 days after treatment) -aspartylpeptidase showed only a significant correlation with the number ofBacteroides spp. This indicates that changes in the indigenous bacterial flora during and shortly after treatment with ceftriaxone can be monitored by determination of -aspartylpeptidase. Recovery of the intestinal flora is difficult to assess in this manner.
Einfluß von Ceftriaxon auf die anaerobe Flora und die bakterielle Enzymaktivität im Intestinaltrakt
Zusammenfassung Die normale Flora des Intestinaltraktes besteht vorweigend aus anaeroben Bakterien und schützt den Wirt gegen eine Kolonisation durch pathogene Mikroorganismen. Eine antimikrobielle Therapie mit Ceftriaxon kann die Mikroflora des Dickdarms beeinträchtigen und damit auch deren protektiven Effekt. Zehn gesunde Probanden erhielten fünf Tage lang 1 g Ceftriaxon intramuskulär appliziert. Dies führte zu einer signifikanten Abnahme der mittleren Koloniebildnerzahlen von 10,67 (SEM ± 0,11) vor Applikation auf 9,02 (± 0,45) nach drei und auf 8,97 (± 0,46) nach fünf Tagen (p<0,05). Nach zehn und 15 bis 19 Tagen im Anschluß an die Antibiotikagabe kehrten die Anaerobier-Koloniebildnerzahlen auf 10,17 (± 0,16) bzw. 10,44 (± 0,18) zurück. Bakterienenzyme können als Indikator für die protektive Mikroflora dienen. In Überständen von Stuhlproben der Probanden wurden -Aspartylpeptidase und Desoxycholat-Hydrolase bestimmt und mit den Anaerobier-Kulturen verglichen. Zwischen den Aktivitäten beider Enzyme und der am Tag 3 gemessenen Anaerobier-Gesamtzahl fand sich eine signifikante Korrelation. Am Tag 5 und Tag 8 zeigte nur die -Aspartylpeptidase eine signifikante Korrelation mit den Gesamt-Kolonie-bildnerzahlen der Anaerobier sowie mit den Zahlen vonBacteroides spp. oder Bifidobakterien. An den Tagen 15 bis 19 (zehn bis 14 Tage nach Antibiotikagabe) bestand nur zwischen der Zahl vonBacteroides spp. und -Aspartylpeptidase eine signifikante Korrelation. Nach Behandlung mit Ceftriaxon lassen sich folglich Veränderungen der bakteriellen Flora kurzfristig durch Bestimmung der -Aspartylpeptidase erfassen, weniger gut aber die Erholung der Darmflora.
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