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101.
Altered host plant volatiles are proxies for sex pheromones in the gall wasp Antistrophus rufus 总被引:2,自引:0,他引:2
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Tooker JF Koenig WA Hanks LM 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(24):15486-15491
We describe a previously uncharacterized function for changes in plant chemistry induced by phytophagous insects: to provide cues for mate location. Larvae of the gall wasp Antistrophus rufus Gillette (Hymenoptera: Cynipidae) feed within inconspicuous galls inside the flowering stems of the prairie perennials Silphium laciniatum L. and Silphium terebinthinaceum Jacquin (Asteraceae). Adult male A. rufus emerge before females and are challenged with locating mates that are sequestered within dead plant stems that occur in a matrix of dead vegetation. Allozyme studies revealed complete reproductive isolation between wasp subpopulations in the two plant species. In laboratory bioassays, males responded only to their natal plant species, antennating the stem surface. Males from S. laciniatum also responded to hexane extracts of S. laciniatum stems, and extracts contained much higher concentrations of monoterpenes (alpha-pinene, beta-pinene, and camphene) than did S. terebinthinaceum. Ratios of "+" and "-" enantiomers of alpha- and beta-pinene approximated 50:50 for nongalled S. laciniatum stems but strongly differed from 50:50 in galled stems, with "+" and "-" enantiomers strongly dominant in different plants. In bioassays, male wasps from S. laciniatum responded to a synthetic blend of the monoterpenes in enantiomeric ratios characteristic of galled stems. Male A. rufus rely entirely on olfaction to locate females within stems in a complex prairie habitat, and gall wasps themselves apparently influence the plant to modify ratios of monoterpene enantiomers. These plant volatiles serve as a signal for males, acting as a sex pheromone proxy for females concealed within plant tissues. 相似文献
102.
Multidisciplinary treatment focusing on impairments, activities and participation are an important component within the therapeutic regimen in musculoskeletal conditions. In Germany, for more than 95% of the patients multidisciplinary treatment is provided as inpatient rehabilitation. According to the results of a study from the Netherlands, inpatient rehabilitation is superior to usual care in terms of decreasing disease activity and improving emotional well-being in rheumatoid arthritis. Another randomized, controlled study gives evidence that rehabilitation is more effective as compared to usual care in ankylosing spondylitis. In patients suffering from fibromyalgia, after inpatient rehabilitation, symptoms improve significantly and this is true even one year after discharge. The results of a quality management project financed by the German health insurance and including several thousand patients with musculoskeletal diseases show an improvement in physical and emotional dimensions of health status at discharge and after a six month follow-up. Recent studies comparing inpatient with outpatient rehabilitation in patients with musculoskeletal diseases provide information that both forms are equally effective. Taking into account the high number of inpatient rehabilitation procedures in Germany, more outcomes research is required urgently. 相似文献
103.
Thomas Hehr Wilfried Budach Ilona Durst Stefan Glocker Johannes Classen Martin Weinmann Gunter Christ Michael Bamberg 《Strahlentherapie und Onkologie》2002,178(11):624-632
BACKGROUND: Different radiotherapy techniques are used for postmastectomy irradiation. We review the results with the electron-beam-rotation technique in advanced breast cancer patients. Main endpoint was local tumor control. PATIENTS AND METHODS: From 1990 to 1998 119 patients with adverse pathology features (pT3 17% of patients, pT4 42%, multicentricity 36%, pN >/= 3 positive nodes and/or pN1biii 81%, close margins 30%) underwent electron-beam-rotation irradiation of the chest wall with daily fractions of 2.0-2.5 Gy per day to 50 Gy total dose after modified radical mastectomy and axillary lymph node dissection. A local boost of 10 Gy and/or irradiation of locoregional lymph nodes were applied depending on the completeness of resection and lymph node involvement. RESULTS: After a median follow-up of 73 months for patients at risk the 5-year local tumor control, local tumor control first event, disease-free, and overall survival were 82%, 92%, 57%, and 63% (Kaplen Meier analysis), respectively. Significant predictors of poor local tumor control were maximal tumor diameter >/= 5 cm (p = 0.01), "close margins" or residual tumor (p < 0.01), four or more involved axillary lymph nodes (p = 0.02), two or more involved lymph node levels (p = 0.04), negative estrogen receptor status (p = 0.03), and high-grade histopathology (GIIb-III, p < 0.01). The subgroup analysis showed a high local failure rate of 37% for high-grade (GIIb-III) and estrogen receptor negative tumors, whereas no local recurrence was found in low-grade (GI-Iia) and receptor positive tumors (p = 0.01). The multivariate analysis revealed maximal tumor diameter >/= 5 cm, four or more involved axillary lymph nodes and high-grade histopathology (GIIb-III) as independent predictors of poor local tumor control. CONCLUSION: In high-risk breast cancer patients postmastectomy irradiation with the electron-beam-rotation technique is an effective therapy, resulting in a 5-year local failure rate of 8%. Intensified local therapy needs further investigation in subgroups of patients with additional risk factors. 相似文献
104.
Amelie Rübel René Handrick Lars H Lindner Matthias Steiger Hansjörg Eibl Wilfried Budach Claus Belka Verena Jendrossek 《Radiation oncology (London, England)》2006,1(1):1-17
Cervical cancer continues to be a significant health burden worldwide. Globally, the majority of cancers are locally advanced at diagnosis; hence, radiation remains the most frequently used therapeutical modality. Currently, the value of adding cisplatin or cisplatin-based chemotherapy to radiation for treatment of locally advanced cervical cancer is strongly supported by randomized studies and meta-analyses. Nevertheless, despite these significant achievements, therapeutic results are far from optimal; thus, novel therapies need to be assayed. A strategy currently being investigated is the use of newer radiosensitizers alone or in combination with platinum compounds. In the present work, we present preclinical information on known and newer cytotoxic agents as radiosensitizers on cervical cancer models, as well as the clinical information emanating from early phase trials that incorporate them to the cervical cancer management. In addition, we present the perspectives on the combined approach of radiation therapy and molecular target-based drugs with proven radiosensitizing capacity. 相似文献
105.
Immunomagnetic enrichment and detection of micrometastases in colorectal cancer: correlation with established clinical parameters. 总被引:6,自引:0,他引:6
Martin R Weihrauch Edmund Skibowski Thomas C Koslowsky Wilfried Voiss Daniel Re Ferdinand Kuhn-Regnier Carolin Bannwarth Michel Siedek Volker Diehl Heribert Bohlen 《Journal of clinical oncology》2002,20(21):4338-4343
PURPOSE: Micrometastatic disease in bone marrow is of prognostic significance in colorectal cancer patients. However, detection rates of standard immunocytology are relatively low. We used magnetic activated cell sorting (MACS), a highly sensitive method, to increase detection rates and correlated the presence of cytokeratin (CK)-expressing cells with clinical parameters. PATIENTS AND METHODS: Bone marrow was obtained from 51 consecutive patients with newly diagnosed colorectal adenocarcinoma who underwent primary surgery and 18 control subjects. International Union Against Cancer (UICC) stage I disease was diagnosed in 11 patients, stage II disease was diagnosed in 14 patients, stage III disease was diagnosed in 12 patients, and stage IV disease was diagnosed in 14 patients. CK-positive cells were enriched and stained with magnetically labeled CAM 5.2 antibodies directed to CK 7 and 8. RESULTS: CK-positive cells were found in 33 (65%) patients and were absent in 18 (35%). Four of 11 (36%) patients with UICC stage I disease, nine of 14 (64%) with stage II diease, eight of 12 (67%) with stage III disease, and 12 of 14 (86%) with stage IV disease were CK-positive. Epithelial cells were more frequently found in pT3/4 (72%) than in pT1/2 (36%) tumors (P =.026), but there was no difference for lymph node status. CK-positive patients had a higher chance for elevated carcinoembryonic antigen (85% v 15%, P = NS) and CA 19-9 levels (92% v 8%, P =.019). There were no significant differences in CA 72-4, sex, age, tumor grading, or tumor localization regarding the presence of CK-positive cells. All control subjects were CK-negative. CONCLUSION: In searching for micrometastases in colorectal cancer patients, we have achieved high detection rates by using MACS. The presence of these cells correlated significantly with tumor stage, tumor extension, and the tumor marker CA 19-9. 相似文献
106.
107.
108.
Compounds with Potentially Positive Inotropic Activity, I: N-Substituted 3-Amino-2-cyclopentenones from Partially Hydrogenated 2-Phenanthrylamines The synthesis of partially hydrogenated 2-phenanthrylamines and their reactions with 1,3-cyclopentanedione to N-substituted 3-amino-2-cyclopentenones is described. 相似文献
109.
Jef Van den Ende Jef Van den Ende Guy Coppens Tom Verstraeten Tine Van Haegenborgh Katrien Depraetere Alfons Van Gompel Erwin Van den Enden Jan Clerinx Robert Colebunders Robert Colebunders Willy E. Peetermans & Wilfried Schroyens 《Tropical medicine & international health : TM & IH》1998,3(8):632-639
Five cases of blackwater fever (BWF) are described, all of whom had a history of recent quinine therapy. In two cases a second haemolytic crisis was induced by halofantrine, in one case also a third. Increasing frequency of this syndrome with its dramatic clinical presentation is to be expected as imported P. falciparum infection, parasite resistance to chloroquine and the use of quinine and other related antimalarials become more frequent. 相似文献
110.
Wilfried M. Brouwer Pieter Piet Anton L. German 《Macromolecular chemistry and physics.》1984,185(2):363-375
Polymeric catalysts consisting of cobalt(II)phthalocyanine, CoPc(NaSO3)4, coordinatively bound to poly(vinylamine) of various molecular weight, were used as oxidation catalysts in the conversion of thiols to disulfides. The molecular weight of the polymeric ligand, poly(vinylamine), largely affects the reaction rate below a critical polymer concentration of about 0,01 w/v%. The activation enthalpy ΔH does not depend on the degree of polymerization (DP) of the polymeric ligand and from visible light spectra it appears that electron transfer of the thiolanion to Co(II) to yield Co(I) is favored when low instead of high molecular weight ligands are used. The observed catalytic oxidation rate of thiol is considerably higher for low molecular weight ligands (DP 20 – 40) in the low polymer concentration region. This may be attributed to a change in base strength in the micro-environment of CoPc(NaSO3)4 due to conformational differences between low and high molecular weight ligands, manifested at low polymer concentration. When the ligand has no polymeric character, e. g. 1, 3-propanediamine, low catalytic activity is observed. 相似文献