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91.
Günter Timmermann 《Parasitology research》1962,21(5):426-436
Ohne ZusammenfassungMit 6 Textabbildungen 相似文献
92.
The indirect alloimmune response seems to be restricted to a few dominant major histocompatibility complex (MHC)-derived peptides responsible for T-cell activation in allograft rejection. The molecular mechanisms of indirect T-cell activation have been studied using peptide analogues derived from the dominant allopeptide in vitro, whereas the in vivo effects of peptide analogues have not been well characterized yet. In the present study, we generated allochimeric peptide analogues by replacing the three allogeneic amino acids 5L, 9L, and 10T in the sequence of the dominant MHC class I allopeptide P1. These allochimeric peptide analogues were used to define the allogeneic amino acids critical for the MHC binding and TCR recognition. We found that position 5 (5L) of the dominant allopeptide acts as an MHC-binding residue, while the other two allogeneic positions, 9 and 10, are important for the T-cell receptor (TCR) recognition. A peptide containing the MHC-binding residue 5L, as the only different amino acid between donor (RT1.A(u)) and recipient (RT1.A(l)) sequences, did not induce proliferation of lymph node cells primed with the dominant peptide and prevented dominant peptide-induced acceleration of allograft rejection. Identification of MHC and TCR contact residues should facilitate the development of antigen-specific therapies to inhibit or regulate the indirect alloimmune response. 相似文献
93.
Treatment of allergic bronchopulmonary aspergillosis (ABPA) has remained both problematic as well as controversial. Although the sheet anchor in treatment of ABPA still remains steroids, various workers have tried oral antifungals (fluconazole and itraconazole) with encouraging results. This study evaluates the effect of fluconazole or itraconazole in the treatment of ABPA patients and compares them with the patients who had received palliative therapy other than antifungals. Case records of 44 proven cases of ABPA treated at our referral service hospital during February 1998 to April 2001 were analyzed. In addition to oral and inhaled bronchodilators, 16 patients received fluconazole 150 mg OD and 13 patients itraconazole 200 mg OD for six months. Response to therapy was assessed clinically, radiologically and by spirometry every 3 months. Patients who did not receive antifungals had chronic course characterized by airway obstruction, recurrent pulmonary consolidation and obstructive defect on pulmonary function test (PFT). Patients treated with itraconazole had better control of asthma symptoms, less requirement of reliever inhalers, steroids and lesser exacerbations of asthma during follow-up even after stopping antifungal. Fluconazole group had better control of symptoms but improvement in other parameters was not statistically significant. From this study it was evident that itraconazole improved the symptoms of airway obstruction, pulmonary functions, pulmonary opacities and decreased exacerbations during follow up.Key Words: Allergic bronchopulmonary aspergillosis, Fluconazole, Itraconazole 相似文献
94.
Oliver?ThomuschEmail author Carsten?Sekulla Andreas?Machens Hans-Jürgen?Neumann Wolfgang?Timmermann Henning?Dralle 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2004,389(6):499-503
Background Although intra-operative neuromonitoring (IONM) is widely used in thyroid surgery, the validity of the received IONM signals are still unknown.Method Prospective collection of data forms in 29 hospitals from 8,534 patients with 15,403 nerves at risk, who underwent surgery for benign and malignant goitre disorders between August 1999 and January 2001. IONM was performed by indirect stimulation via the vagal nerve and by direct recurrent laryngeal nerve (RLN) stimulation in 12,486 cases. IONM signals were compared with early (<14 days) and late (6 months) postoperative vocal cord function findings.Results The transient and permanent RLN palsy rate was 2.8% and 0.7%, respectively. Monitoring of the RLN function was significantly more reliable via the indirect IONM stimulation route than via the direct IONM stimulation route (specificity P<0.05). IONM by indirect stimulation via the vagal nerve reliably excluded postoperative, permanent, vocal cord palsy (specificity 97.6%, negative predictive value 99.6%). However, a changed IONM was insufficient to predict permanent RLN palsy (sensitivity 45.9%, positive predictive value 11.6%). IONM was not associated with increased general morbidity.Conclusions For intra-operative neuromonitoring, indirect stimulation of the RLN is superior to direct stimulation. An intact acoustic IONM signal is highly predictive of intact postoperative RLN function. When the IONM signal is abnormal or absent, a one-stage extensive thyroid resection should be performed only if the surgeon is absolutely convinced that the first RLN is not harmed or a total thyroidectomy is mandatory. 相似文献
95.
Gu JQ Wang Y Franzblau SG Montenegro G Timmermann BN 《Journal of natural products》2004,67(9):1483-1487
Two new sesquiterpenoids, (1S,4S,5R,10R)-1-hydroxy-6-isobutyryloxy-10H-9-oxofuranoeremophilane (1) and 1alpha-hydroxy-6beta-(2xi-methylbutyryloxy)-10alphaH-9-oxofuranoeremophilane (2), along with 21 known constituents, were isolated from the n-hexane and dichloromethane extracts of the above-ground biomass and roots of Senecio chionophilus. The structures of 1 and 2 were elucidated on the basis of spectroscopic evidence and chemical transformation methods. The absolute configuration of 1 was determined by Mosher ester methodology. All of the isolates were evaluated for their antitubercular potential against Mycobacterium tuberculosis in a microplate Alamar Blue assay. Compound 2, 6beta-angeloyloxy-1alpha-hydroxy-10alphaH-9-oxofuranoeremophilane (3), and 4'-hydroxyacetophenone (6) exhibited mild antitubercular activity at minimum inhibitory concentrations of 119, 114, and 121 microg/mL, respectively. 相似文献
96.
Mucuna pruriens in Parkinson's disease: a double blind clinical and pharmacological study 总被引:1,自引:0,他引:1 下载免费PDF全文
Katzenschlager R Evans A Manson A Patsalos PN Ratnaraj N Watt H Timmermann L Van der Giessen R Lees AJ 《Journal of neurology, neurosurgery, and psychiatry》2004,75(12):1672-1677
BACKGROUND: The seed powder of the leguminous plant, Mucuna pruriens has long been used in traditional Ayurvedic Indian medicine for diseases including parkinsonism. We have assessed the clinical effects and levodopa (L-dopa) pharmacokinetics following two different doses of mucuna preparation and compared them with standard L-dopa/carbidopa (LD/CD). METHODS: Eight Parkinson's disease patients with a short duration L-dopa response and on period dyskinesias completed a randomised, controlled, double blind crossover trial. Patients were challenged with single doses of 200/50 mg LD/CD, and 15 and 30 g of mucuna preparation in randomised order at weekly intervals. L-dopa pharmacokinetics were determined, and Unified Parkinson's Disease Rating Scale and tapping speed were obtained at baseline and repeatedly during the 4 h following drug ingestion. Dyskinesias were assessed using modified AIMS and Goetz scales. RESULTS: Compared with standard LD/CD, the 30 g mucuna preparation led to a considerably faster onset of effect (34.6 v 68.5 min; p = 0.021), reflected in shorter latencies to peak L-dopa plasma concentrations. Mean on time was 21.9% (37 min) longer with 30 g mucuna than with LD/CD (p = 0.021); peak L-dopa plasma concentrations were 110% higher and the area under the plasma concentration v time curve (area under curve) was 165.3% larger (p = 0.012). No significant differences in dyskinesias or tolerability occurred. CONCLUSIONS: The rapid onset of action and longer on time without concomitant increase in dyskinesias on mucuna seed powder formulation suggest that this natural source of L-dopa might possess advantages over conventional L-dopa preparations in the long term management of PD. Assessment of long term efficacy and tolerability in a randomised, controlled study is warranted. 相似文献
97.
Chemical investigation of the aerial parts of Anadenanthera colubrina led to the isolation of a new flavonoid named anadanthoflavone ( 1), along with 11 known compounds: alnusenol, lupenone, lupeol, betulinic acid, alpha-amyrin, beta-amyrin, beta-sitosterol, stigmasterol, apigenin, 4-hydroxybenzoic acid and cinnamic acid. The isolated compounds were evaluated for their inhibitory activity on human platelet 12-lipoxygenase (12-hLO), human reticulocyte 15-lipoxygenase (15-hLO) and soybean lipoxygenase-1 (15-sLO). Compound 1 was found to be active against 12-hLO and 15-hLO with IC50 values of 13 +/- 3 microM and 17 +/- 3 microM, respectively. Apigenin selectively inhibited the activity of 15-hLO (IC50 : 4.0 +/- 1 microM), while lupenone, lupeol and alpha-amyrin were found active against 15-sLO (IC50 : 22 +/- 3 microM, 35 +/- 9 microM and 15 +/- 3 microM, respectively). 相似文献
98.
Perl T Bräuer A Timmermann A Mielck F Weyland W Braun U 《Acta anaesthesiologica Scandinavica》2003,47(9):1159-1164
BACKGROUND: Forced-air warming is known as an effective procedure in prevention and treatment of perioperative hypothermia. Significant differences have been described between forced-air warming systems in combination with full body blankets. We investigated four forced-air warming systems in combination with upper body blankets for existing differences in heat transfer. METHODS: After approval of the local Ethics Committee and written informed consent, four forced-air warming systems combined with upper body blankets were investigated in a randomized cross-over trial on six healthy volunteers: (1) BairHugger trade mark 505 and Upper Body Blanket 520, Augustine Medical; (2) ThermaCare trade mark TC 3003, Gaymar trade mark and Optisan trade mark Upper Body Blanket, Brinkhaus; (3) WarmAir trade mark 134 and FilteredFlow trade mark Upper Body Blanket, CSZ; and (4) WarmTouch trade mark 5800 and CareDrape trade mark Upper Body Blanket, Mallinckrodt. Heat transfer from the blanket to the body surface was measured with 11 calibrated heat flux transducers (HFTs) with integrated thermistors on the upper body. Additionally, the blanket temperature was measured 1 cm above the HFT. After a preparation time of 60 min measurements were started for 20 min. Mean values were calculated over 20 min. The t-test for matched pairs with Bonferroni-Holm-correcture for multiple testing was used for statistical evaluation at a P-level of 0.05. The values are presented as mean+/-SD. RESULTS: The WarmTouch trade mark blower with the CareDrape trade mark blanket obtained the best heat flux (17.0+/-3.5 W). The BairHugger trade mark system gave the lowest heat transfer (8.1+/-1.1 W). The heat transfer of the ThermaCare trade mark system and WarmAir trade mark systems were intermediate with 14.3+/-2.1 W and 11.3+/-1.0 W. CONCLUSIONS: Based on an estimated heat loss from the covered area of 38 W the heat balance is changed by 46.1 W to 55 W by forced-air warming systems with upper body blankets. Although the differences in heat transfer are significant, the clinical relevance of this difference is small. 相似文献
99.
Khera S Woldemichael GM Singh MP Suarez E Timmermann BN 《Journal of natural products》2003,66(12):1628-1631
Bioassay-guided fractionation of the antibacterial CH(2)Cl(2)-MeOH extract obtained from the aerial parts of the Argentinean plant Caiophora coronata led to the isolation of a new triterpene, 1beta,3beta-dihydroxyurs-12-en-27-oic acid, 1, and a new iridoid, 1alpha-methoxy-6alpha,10-dihydroxyisoepiiridomyrmecin (caiophoraenin), 2, along with the known iridoid isoboonein 3. Their structures were established by spectroscopic techniques (1D and 2D NMR, HRFABMS, FTIR). The MIC values of isolated compounds were determined against methicillin-sensitive (MSSA) and -resistant (MRSA) strains of Staphylococcus aureus, Bacillus subtilis (BS), vancomycin-resistant Enterococcus faecium (VREF), Escherichia coli (EC), E. coli imp (ECimp), and Candida albicans (CA). Compound 1 was found active against BS, MSSA, MRSA, VREF, and ECimp with MIC values of 2, 4, 4, 4, and 16 microg/mL, respectively. 相似文献
100.
Basic ecophysiological data are presented on the development and reproduction of Aedes albopictus (Skuse) that were reared and maintained at four temperatures between 12 and 32 degrees C. Median larval developmental time from hatching to pupation was correlated inversely with temperature, lasting 7 d at 32 degrees C and up to 28 d at 12 degrees C. Duration of the pupal period also varied from 2-3 d at 32 degrees C to 7-12 d at 12 degrees C. This extension of larval development elongated the phagoperiod and gave rise to larger imagoes. Based on wing length measurements, body sizes varied from 10 to 57 mm3 for females and from 10 to 30 mm3 for males. The caloric protein content at emergence showed a linear and significant regression with body size, independent of sex, treatment, or temperature. Teneral lipid content also followed a linear relationship with body size at warmer temperatures, whereas at low temperatures it increased exponentially with body size. Glycogen was always below 10% of the protein or lipid levels. Reserves at emergence determined median adult survival times, which ranged from 16 d at 32 degrees C to 100 d at 17 degrees C. Access to sucrose solution allowed females to increase their teneral glycogen up to fourfold within 1 wk, and their lipids up to 10-fold within 2 wk. Despite abroad variation, the number of mature oocytes (15-110 eggs per female) was correlated positively with body size, but inversely with the rearing and maintenance temperature. Utilization of the blood meal protein for oogenesis ranged between 35 and 50%, again inversely correlated with temperature; absolute compositions per oocyte were 6.3-6.5 mcal of protein but ranged from 5 to 7 mcal of lipid. 相似文献