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排序方式: 共有2297条查询结果,搜索用时 609 毫秒
91.
Krastel P Zeeck A Gebhardt K Fiedler HP Rheinheimer J 《The Journal of antibiotics》2002,55(9):801-806
A detailed screening of the secondary metabolite pattern produced by different athropod associated strains of the species Streptomyces anulatus resulted in the isolation and structure elucidation of the endophenazines A-D (2, 4-6). The structures were assigned by spectroscopic methods and chemical transformations. 4 represents a chromophoric system based on a phenazin-7-one, 5 and 6 are new 5,10-dihydrophenazine derivatives. 相似文献
92.
Schimana J Gebhardt K Höltzel A Schmid DG Süssmuth R Müller J Pukall R Fiedler HP 《The Journal of antibiotics》2002,55(6):565-570
New lipopeptide antibiotics, colourless arylomycins A series and yellow arylomycins B series were detected in the culture filtrate and mycelium extracts of Streptomyces sp. Tü 6075 by HPLC-diode-array and HPLC-electrospray-mass-spectrometry screening. Arylomycins are a family of lipohexapeptide antibiotics, which represent the first examples of biaryl-bridged lipopeptides. They show antibiotic activities against Gram-positive bacteria. 相似文献
93.
Auer-Grumbach M De Jonghe P Verhoeven K Timmerman V Wagner K Hartung HP Nicholson GA 《Archives of neurology》2003,60(3):329-334
Hereditary sensory neuropathies (HSNs) are rare disorders characterized by progressive distal sensory loss, predominantly affecting the lower limbs. Foot ulcers, severe skin and bone infections, arthropathy, and amputations are frequent and feared complications. Occasionally, patients complain of spontaneous shooting or lancinating pain. Autonomic fibers can be affected to a variable degree. Patients with HSN can also have severe distal weakness, and some HSN variants have therefore been classified among the hereditary motor and sensory neuropathies (HMSNs). Molecular genetic studies of autosomal dominant inherited neuropathies with prominent sensory loss and ulceromutilating features have assigned the genetic loci for HMSN type 2B (Charcot-Marie-Tooth syndrome type 2B) and HSN type 1 to chromosomes 3q13-22 and 9q22.1-22.3, respectively. However, some families with HSN have been excluded for linkage to these loci, suggesting further genetic heterogeneity. Recently, disease-causing mutations in the SPTLC1 gene have been identified in patients with HSN type 1. In this review, we discuss the hallmark features associated with the distinct genetic subtypes of autosomal dominant inherited HSN and provide genotype-phenotype correlations. 相似文献
94.
A possible influence of gingival dimensions on attachment loss and gingival recession following placement of artificial crowns 总被引:1,自引:0,他引:1
Koke U Sander C Heinecke A Müller HP 《The International journal of periodontics & restorative dentistry》2003,23(5):439-445
The aim of the present study was to determine the influence of gingival dimensions on the development of gingival recession following placement of artificial crowns. The study population consisted of 11 periodontally healthy patients in whom 44 maxillary anterior teeth and/or premolars had to be crowned. A total of 36 teeth (82%) had, after crown placement, a mean intracrevicular crown margin of 0.57 +/- 0.47 mm. Thirty-nine teeth without restorations served as controls. Immediately after incorporation, as well as after 3, 6, 9, and 12 months, periodontal examinations were carried out. Gingival thickness was determined sonometrically and averaged 1.25 +/- 0.40 mm. Mean periodontal probing depth was 1.80 +/- 0.54 mm. Twelve months later, crowned teeth had experienced a mean attachment loss of 0.17 +/- 0.99 mm as compared to an attachment gain of 0.18 +/- 0.46 mm at control teeth. At test teeth, the gingival margin had receded a mean of 0.43 +/- 0.74 mm. In multivariate analyses considering the correlated structure of the data employing generalized estimating equation methods, crown placement was identified as a major factor for attachment loss and development of gingival recession. In addition, a shallow probing depth and narrow band of gingiva negatively influenced the level of periodontal attachment. The present results point to the importance of a more detailed periodontal diagnosis of the dentogingival region before placement of artificial crowns. 相似文献
95.
Swanson KS Grieshop CM Flickinger EA Bauer LL Healy HP Dawson KA Merchen NR Fahey GC 《The Journal of nutrition》2002,132(5):980-989
The goal of this study was to examine whether supplemental fructooligosaccharides (FOS) and (or) mannanoligosaccharides (MOS) influenced indices of gut health of dogs. Adult female dogs (n = 4) surgically fitted with ileal cannulas were fed a dry, extruded, kibble diet twice daily. At each feeding, the following treatments were administered: 1) Control (no FOS or MOS); 2) 1 g FOS; 3) 1 g MOS; or 4) 1 g FOS + 1 g MOS. Fecal, ileal and blood samples were collected during the last 4 d of each 14-d period to measure protein catabolite concentrations, microbial populations, immune characteristics and nutrient digestibilities. Treatment means were compared using preplanned orthogonal contrasts. Dogs supplemented with MOS had lower (P = 0.05) fecal total aerobes and tended to have greater (P = 0.13) Lactobacillus populations. Ileal immunoglobulin (Ig) A concentrations were greater (P = 0.05) in dogs supplemented with FOS + MOS vs. control. Lymphocytes (% of total white blood cells) were greater (P < 0.05) in dogs supplemented with MOS. Serum IgA concentrations also tended (P = 0.13) to be greater in dogs supplemented with MOS. Dogs supplemented with FOS and FOS + MOS had lower (P < 0.05) fecal total indole and phenol concentrations. Dogs supplemented with MOS tended to have lower ileal DM (P = 0.149) and OM (P = 0.146) digestibilities vs. control. Results of this study suggest that dietary supplementation of FOS and MOS may have beneficial effects on colonic health and immune status of dogs. 相似文献
96.
The aim of our project is to analyze the functional meaning of neurocognitive components of the Continuous Performance Tests (CPT), which may be responsible for the well-documented performance deficit. Since the CPT can be considered as a vulnerability marker for schizophrenia, this question is of special interest. We set up a test battery testing five different cognitive processing modes: perceptual organization, selective attention, short-term memory (storing component), working memory (rehearsal component), and vigilance/sustained attention. In order to avoid the pitfall of interpreting results confounded by psychometric differences within tasks, we created psychometrically parallel versions within each experimental block (following the proposals of Chapman and Chapman [J. Nerv. Ment. Dis. 171 (1983) 658]). At the main experimental session, we tested newly admitted patients with a DSM diagnosis of schizophrenia during remission (N=30), patients with major depressive disorder (MD) (N=18), and healthy controls (N=20). Results showed that differences specific for schizophrenia are seen at the experimental block, which tests perceptual organization. However, all levels of perceptual organization performance were concerned, i.e., from processing organized to non-organized patterns. The regression analysis showed that 3-7 CPT version performances could be explained by problems with short-term memory, sustained attention, and perceptual organization. In light of these findings, we discussed whether etiology of schizophrenia could be conceptualized as a circumscribed neurocognitive deficit or a multifunctional, multilocal deficit. 相似文献
97.
Volz HP Möller HJ Gerebtzoff A Bischoff S 《European archives of psychiatry and clinical neuroscience》2002,252(2):76-80
Savoxepine, an atypical neuroleptic compound developed in the 1980s, was believed to act via selective limbic dopamine D2-receptor blockade. The results of the presented double-blind, randomised, controlled clinical trial comparing savoxepine
(n = 58) with haloperidol (n = 29) did not confirm the preclinical data suggesting that savoxepine would produce fewer extrapyramidal
symptoms than the comparator. Animal data and PET-results obtained a posteriori suggested that this unfavourable outcome may have been due to the conventional, step-wise dose increase strategy used in
the study leading to a high dopamine D2-receptor occupancy in the striatum thus eliciting EPS. Using either a slower dose-titration or a high, single loading dose
followed by a low maintenance dosing may have offered the possibility to obtain a good antipsychotic effect together with
low incidence of EPS. In future clinical trials with new neuroleptics, the preclinical data should be carefully evaluated,
and drug brain kinetic parameters taken into consideration.
Received: 4 December 2001 / Accepted: 5 April 2002 相似文献
98.
Anti-p53 in breast cancer: concordance of different assay procedures and association with p53 antigen expression 总被引:3,自引:0,他引:3
Volkmann M Sinn HP Gaugel D Frey M Hajjar Y Ludwig J Hänsel S Bastert G Wallwiener D Fiehn W Zentgraf H Huober J 《Oncology》2002,63(3):297-305
OBJECTIVE: Anti-p53 levels detected by different methods were compared in a predefined group of patients with breast cancer and correlated with p53 antigen expression in the corresponding tumors. METHODS: P53 autoantibodies were investigated in 165 patients with primary breast cancer using ELISAs with recombinant or native p53. Immunoblot and indirect immunofluorescence (Huh7) were used for confirmation, p53 antigen expression in the tumor was determined immunohistochemically. RESULTS: Using ELISA, overall 18/165 positives (11%) were detected, with only partly concordant results between the assays. Five positive sera were confirmed by immunoblot, and three also by indirect immunofluorescence. Anti-p53-positive patients detected by more than two assays showed accumulated p53 in the tumor (6/6) and mostly suffered from recurrent tumors (4/6; p = 0.02). In these cases, a trend towards a shortened disease-free interval was found (26 vs. 49 months; n.s.). In patients with a positive or borderline result in only one of the serological methods, there was no increased rate of p53 accumulation compared to anti-p53-negative patients (4/19 versus 35/126). CONCLUSIONS: Lack of assay standardization may partly explain the divergence in reports on anti-p53 and its clinicopathological associations. We speculate that, in different groups of patients, anti-p53 might be induced by different mechanisms. 相似文献
99.
The intracellular pH value has a profound influence on cerebral metabolism. Thus, inadequate pH control may intensify local metabolic deficits. To investigate the influence of neuroleptics on cerebral intracellular pH, we retrospectively evaluated the findings from three independent phosphorous-31 magnetic resonance spectroscopy ((31)P-MRS) studies on schizophrenic patients. A total sample of 72 patients and 32 healthy controls was investigated. A modified pH value was found only in those schizophrenic patients treated with the atypical neuroleptic clozapine. 相似文献
100.
Gille G Rausch WD Hung ST Moldzio R Janetzky B Hundemer HP Kolter T Reichmann H 《Journal of neural transmission (Vienna, Austria : 1996)》2002,109(5-6):633-643
Summary. Dopamine agonists are an important therapeutic strategy in the treatment of Parkinson's disease. They postpone the necessity
for and reduce the required dose of L-3,4-dihydroxyphenylalanine (L-DOPA) medication thus protecting against the development
of motor complications and potential oxidative stress due to L-DOPA metabolism. In primary cultures from mouse mesencephalon
we show that pergolide, a preferential D2 agonist enhanced the survival of healthy dopaminergic neurons at low concentrations of 0.001 μM. About 100 fold higher concentrations
(0.1 μM) were necessary to partially reverse the toxic effects of 10 μM 1-methyl-4-phenylpyridinium (MPP+). Pergolide was equally effective in preventing the reduction of dopamine uptake induced by 200 μM L-DOPA. Furthermore, between
0.001–0.1 μM it also reduced lactate production thus promoting aerobic metabolism. The present findings suggest that pergolide
protects dopaminergic neurons under conditions of elevated oxidative stress.
Received February 4, 2002; accepted February 21, 2002 相似文献