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71.
A diamine monomer containing the 1,3-biscyclohexyl-1-methylindan group was prepared, starting from cyclohexyl phenyl ketone in four steps. This monomer was reacted with six different dianhydrides (pyromellitic dianhydride, 3,4:3′,4′-biphenyltetracarboxylic dianhydride, 3,4:3′,4′-benzophenonetetracarboxylic dianhydride, 4,4′-oxydiphthalic anhydride, 4,4′-sulfonyldiphthalic anhydride, 4,4′-perfluoroisopropylidenediphthalic anhydride) to give the corresponding polyimides via the poly(amic acid) precursors and thermal imidization. All of these polyimides were soluble at least in N-methyl-2-pyrrolidone (NMP) at elevated temperatures, some were soluble in NMP and chlorinated hydrocarbons even at room temperature. The polymers were characterized by nuclear magnetic resonance spectroscopy, differential scanning calorimetry, and dynamic thermogravimetry. All polyimides proved to be amorphous with glass transition temperatures in the range between 261°C and 295°C depending on the nature of the dianhydride moiety. Their decomposition proceeds in two steps, starting at 400°C probably with loss of the cyclohexyl substituents. 相似文献
72.
Nikol S Maier A Krausz E Höfling B Huehns TY 《BioDrugs : clinical immunotherapeutics, biopharmaceuticals and gene therapy》1998,9(5):375-388
No systemic pharmacological treatment has been convincingly shown to reduce the incidence of restenosis after angioplasty in patients. The lack of success of many pharmaceutical agents in reducing restenosis rates post-angioplasty and following stent implantation, as documented in dozens of clinical trials, has encouraged the development of new biotechnological approaches to the treatment of restenosis. Gene therapy and other agents, including antibodies, fusion toxins and ribozymes, have the potential to prevent some of the sequelae after arterial injury, particularly cell proliferation. Mechanical methods of preventing restenosis, for example sophisticated local drug delivery strategies and biodegradable stents using new materials, in combination with novel therapeutic agents or radiation, may also be of use. 相似文献
73.
Operational diagnoses of endogenous depression have gained special importance for psychopharmacological research. The high reliability of operationally defined diagnoses is a prerequisite for sampling comparable patient group. The simultaneous application of competing categorical diagnostic system ("polydiagnosis") allows us to determine whether differences in research findings are due to differences in patient samplings. Furthermore, a dimensional classification of patients by means of a newly developed polydiagnostic scale (so called OPD scale) allows us to compare the diagnostic homogeneity of patient groups diagnosed as endogenous depression cases and to select extreme groups with high diagnostic homogeneity for comparing the distribution of variables under research in patients with endogenous and nonendogenous depression. 相似文献
74.
Gabriele Piuri Monica Zocchi Matteo Della Porta Valentina Ficara Michele Manoni Gian Vincenzo Zuccotti Luciano Pinotti Jeanette A. Maier Roberta Cazzola 《Nutrients》2021,13(2)
Magnesium (Mg2+) deficiency is probably the most underestimated electrolyte imbalance in Western countries. It is frequent in obese patients, subjects with type-2 diabetes and metabolic syndrome, both in adulthood and in childhood. This narrative review aims to offer insights into the pathophysiological mechanisms linking Mg2+ deficiency with obesity and the risk of developing metabolic syndrome and type 2 diabetes. Literature highlights critical issues about the treatment of Mg2+ deficiency, such as the lack of a clear definition of Mg2+ nutritional status, the use of different Mg2+ salts and dosage and the different duration of the Mg2+ supplementation. Despite the lack of agreement, an appropriate dietary pattern, including the right intake of Mg2+, improves metabolic syndrome by reducing blood pressure, hyperglycemia, and hypertriglyceridemia. This occurs through the modulation of gene expression and proteomic profile as well as through a positive influence on the composition of the intestinal microbiota and the metabolism of vitamins B1 and D. 相似文献
75.
Ching Shan Wan Jade Mitchell Andrea B. Maier 《Journal of the American Medical Directors Association》2021,22(6):1331.e1-1331.e9
ObjectivesTo evaluate the effect of Hospital Admission Risk Program (HARP) on unplanned hospitalization, bed days, and mortality of enrolled individuals and to evaluate the cost-effectiveness of HARP.DesignA retrospective longitudinal analysis of hospital administrative data.InterventionIndividuals at risk of hospitalization were provided with multidisciplinary, community-based care support managed by care coordinators including integrated care planning, education, monitoring, service linkages, and general practitioner liaison over 6-9 months.Setting and ParticipantsIndividuals who were enrolled into 1 of 8 HARP chronic disease management programs between July 1, 2017, and June 30, 2018, at the Royal Melbourne Hospital, Australia.MethodsHospital admissions between 18 months before and 18 months after HARP enrollment were analyzed. Total hospital costs were compared between 18 months before and 12 months after HARP enrollment.ResultsA total of 1553 individuals with a median age of 71 years (interquartile range 60-81), 63.4% males, were admitted to HARP. Both unplanned hospitalizations and bed days were reduced during the HARP intervention compared to within 3 months before enrollment in each of the HARP management programs. After the HARP intervention, cardiac coach, cardiac heart failure, chronic respiratory, diabetes comanagement, and medication management programs had higher hospitalizations and bed days than individuals’ baseline of at least 3 months before HARP enrollment. Individuals in cardiac heart failure and chronic respiratory management programs had a higher mortality rate than other HARP chronic disease management programs. Individuals in cardiac coach, diabetes comanagement, and medication management programs had lower hospital costs during the HARP intervention compared to within 3 months before HARP enrollment.Conclusions and ImplicationsHARP reduced unplanned hospitalization and bed days but did not return individuals’ hospital use to baseline before the intervention. The variations in mortality between HARP chronic disease management programs implies that condition-specific goals between programs is preferable. 相似文献
76.
Jesse J. Aarden Esmee M. Reijnierse Marike van der Schaaf Martin van der Esch Lucienne A. Reichardt Rosanne van Seben Jos A. Bosch Jos W.R. Twisk Andrea B. Maier Raoul H.H. Engelbert Bianca M. Buurman 《Journal of the American Medical Directors Association》2021,22(4):839-845.e1
ObjectivesAcute hospitalization may lead to a decrease in muscle measures, but limited studies are reporting on the changes after discharge. The aim of this study was to determine longitudinal changes in muscle mass, muscle strength, and physical performance in acutely hospitalized older adults from admission up to 3 months post-discharge.DesignA prospective observational cohort study was conducted.Setting and ParticipantsThis study included 401 participants aged ≥70 years who were acutely hospitalized in 6 hospitals. All variables were assessed at hospital admission, discharge, and 1 and 3 months post-discharge.MethodsMuscle mass in kilograms was assessed by multifrequency Bio-electrical Impedance Analysis (MF-BIA) (Bodystat; Quadscan 4000) and muscle strength by handgrip strength (JAMAR). Chair stand and gait speed test were assessed as part of the Short Physical Performance Battery (SPPB). Norm values were based on the consensus statement of the European Working Group on Sarcopenia in Older People.ResultsA total of 343 acute hospitalized older adults were included in the analyses with a mean (SD) age of 79.3 (6.6) years, 49.3% were women. From admission up to 3 months post-discharge, muscle mass (?0.1 kg/m2; P = .03) decreased significantly and muscle strength (?0.5 kg; P = .08) decreased nonsignificantly. The chair stand (+0.7 points; P < .001) and gait speed test (+0.9 points; P < .001) improved significantly up to 3 months post-discharge. At 3 months post-discharge, 80%, 18%, and 43% of the older adults scored below the cutoff points for muscle mass, muscle strength, and physical performance, respectively.Conclusions and ImplicationsPhysical performance improved during and after acute hospitalization, although muscle mass decreased, and muscle strength did not change. At 3 months post-discharge, muscle mass, muscle strength, and physical performance did not reach normative levels on a population level. Further research is needed to examine the role of exercise interventions for improving muscle measures and physical performance after hospitalization. 相似文献
77.
Cytosolic oestrogen and progesterone receptors (ER and PR) were determined in 58 primary and 13 recurrent meningiomas and related to their histological and clinical features. ER levels were low or not detectable (range 0-34 fmol/mg prot., median 0 fmol), whereas considerable amounts of PR were found in 69% of primary tumours (range 0-583 fmol/mg prot., median 72 fmol) and in 5/5 long-term recurrences (range 69-505 fmol/mg prot., median 143). Eight tumours recurred within a short-term period (less than 5 years) with a low PR expression (range 0-34 fmol/mg prot., median 0 fmol) and all presented raised cellularity and mitotic rate ("atypical" meningioma) or criteria of definitely malignant meningioma. The primary tumours of the short-term recurrences were not available for receptor analysis; however, they also were either "atypical" or anaplastic meningiomas. Long-term recurrences never displayed other than classical histology. From our results we conclude that polymorphy, as well as a lack of PR are strong indicators for short-term recurrence. 相似文献
78.
M. Fleshner D. Bellgrau L.R. Watkins M.L. Laudenslager S.F. Maier 《Journal of neuroimmunology》1995,56(1):45-52
Exposure to aversive events or Stressors modulates various aspects of immune function. We have previously reported that exposure to an acute Stressor, inescapable tail shock (IS), resulted in a shift in T cell subpopulations in rat mesenteric lymph nodes but not in cervical lymph nodes (Fleshner et al. (1992) J. Neuroimmunol. 41, 131–142). The mesenteric ratio was increased immediately after exposure to IS and was due primarily to an increase in the percent of CD4+ cells. The present experiments were designed to determine the relationship between the IS-associated phenotypic shift and its significance in the function of CD4+ T cells. The function assessed was the in vitro proliferative response to alloantigens coded for by the Major Histocompatibility Complex (MHC). Using the mixed lymphocyte reaction (MLR), we report that exposure to IS resulted in a decrease in the MLR response of cells from both cervical and mesenteric lymph nodes. Depletion of macrophages (nylon wool adherent cells) eliminated the IS-induced reduction and co-culture of macrophages (irradiation-insensitive cells) from shocked rats produced the suppression. One interpretation of these data is that exposure to IS resulted in the activation of macrophages and the release of a suppressive factor which reduced the MLR response of peripheral lymph node lymphocytes. 相似文献
79.
Thomas BV Knight AW Maier KJ 《Archives of environmental contamination and toxicology》1999,36(3):295-300
The input of selenium from subsurface agricultural drainage into surface water systems can result in the accumulation of
toxic concentrations of selenium in aquatic food chains. Elevated selenium concentrations in aquatic systems is a significant
environmental problem in many areas of the United States. A laboratory investigation was conducted to determine the dominant
route of selenium bioaccumulation by the corixid Trichocorixa reticulata, an important food chain organism. The roles of waterborne and foodborne exposure in selenium bioaccumulation were examined
using 48-h bioassays. Waterborne selenium concentrations ranged from 0 to 1,000 μg Se/L as selenate. A mixture of two species
of blue-green algae cultured in media with selenium concentrations ranging from 0 to 1,000 μg Se/L as selenate was used as
a corixid diet in the foodborne treatments. Corixids exposed to waterborne selenate did not accumulate selenium above control
concentrations. Corixids fed algae exposed to ≥100 μg Se/L as selenate had significantly higher selenium concentrations than
control organisms. These data suggest that corixids may be effectively isolated from the water and selenium accumulation is
solely through dietary exposure.
Received: 8 July 1998/Accepted: 21 October 1998 相似文献
80.
Deckert J Catalano M Syagailo YV Bosi M Okladnova O Di Bella D Nöthen MM Maffei P Franke P Fritze J Maier W Propping P Beckmann H Bellodi L Lesch KP 《Human molecular genetics》1999,8(4):621-624
A genetic contribution to the pathogenesis of panic disorder has been demonstrated by clinical genetic studies. Molecular genetic studies have focused on candidate genes suggested by the molecular mechanisms implied in the action of drugs utilized for therapy or in challenge tests. One class of drugs effective in the treatment of panic disorder is represented by monoamine oxidase A inhibitors. Therefore, the monoamine oxidase A gene on chromosome X is a prime candidate gene. In the present study we investigated a novel repeat polymorphism in the promoter of the monoamine oxidase A gene for association with panic disorder in two independent samples (German sample, n = 80; Italian sample, n = 129). Two alleles (3 and 4 repeats) were most common and constituted >97% of the observed alleles. Functional characterization in a luciferase assay demonstrated that the longer alleles (3a, 4 and 5) were more active than allele 3. Among females of both the German and the Italian samples of panic disorder patients (combined, n = 209) the longer alleles (3a, 4 and 5) were significantly more frequent than among females of the corresponding control samples (combined, n = 190, chi2 = 10.27, df = 1, P = 0.001). Together with the observation that inhibition of monoamine oxidase A is clinically effective in the treatment of panic disorder these findings suggest that increased monoamine oxidase A activity is a risk factor for panic disorder in female patients. 相似文献