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31.
Angiogenesis is thought to be an important factor for tumour growth and metastatic spread, and microvessel counts may provide useful prognostic information for several tumour types. To investigate the prognostic impact of angiogenesis in endometrial carcinoma patients, the intratumour microvessel density, which was determined immunohistochemically, has been related to survival. Sixty patients with endometrial carcinoma with long (median 19 years) and complete follow-up have been studied. Patients with increased mean microvessel density (MVDmean > 68 mm2) had a significantly shorter 5-year survival compared with the rest (57% vs 90%, P = 0.004). In multivariate survival analyses, MVDmean had an independent prognostic impact (P = 0.03) when FIGO stage, histological type, histological grade as well as nuclear p53 protein expression was adjusted for. These findings indicate that intratumour microvessel density may contribute additional prognostic information to that obtained from the known risk factors and may be helpful in identifying endometrial carcinoma patients at high risk for disease progression. 相似文献
32.
Microinjections of amphetamine into the ventrolateral striatum (VLS) elicit a striking behavioral syndrome characterized by compulsive oral and forelimb motor stereotypies. The neural pathways that mediate these behavioral responses downstream from the striatum have not yet been identified. In a series of experiments, we investigated the involvement of the substantia nigra pars reticulata (SNr) and the ventromedial nucleus of the thalamus (VMT) in the mediation of this behavioral syndrome. We demonstrated that lidocaine-induced reversible inactivation of the SNr reduced amphetamine-induced stereotyped biting and gnawing behaviors, suggesting that the nigral output pathway plays a significant role in the expression of these behavioral responses. In turn, injections of lidocaine into the VMT only transiently reduced amphetamine-stimulated biting and increased stereotyped gnawing and paw nibbling, suggesting that the expression of oral stereotypies induced by amphetamine injections into the VLS is not dependent on thalamocortical feedback. 相似文献
33.
A Jakobsen P Iversen C Gadeberg J L Hansen M Hjelm-Hansen 《Radiotherapy and oncology》1987,8(2):145-151
A new system for patient fixation in radiation treatment is described. The system consists of an airtight plastic bag with a contents of polysterol microspheres. A valve allows evacuation which results in a rigid close fitting cast. The system was compared with conventional foam cast fixation in 29 patients who were treated for carcinoma of the breast. The patients received radiation treatment over 22 fractions, and portal X-ray pictures were obtained at every second treatment. The portal films were compared with the stimulator radiographs and the variation in the position of the centre cross were measured in cranio-caudal and transversal direction as well as the rotation of the centre cross. The results showed that the daily reproducibility of the patient set-up was considerably improved by the new system, the centre cross deviation of the position of the actual radiation field to the centre cross of the intended field being less than 1 mm in 50% of the cases. The system is time-saving and cheap compared to conventional fixation systems. 相似文献
34.
Tenna Vesterman Henriksen Thomas Reinert Mads Heilskov Rasmussen Christina Demuth Uffe Schou Lve Anders Husted Madsen Kre Andersson Gotschalck Lene Hjerrild Iversen Claus Lindbjerg Andersen 《Molecular oncology》2022,16(20):3654
Circulating tumour DNA (ctDNA) detection for postoperative risk stratification in cancer patients has great clinical potential. However, low ctDNA abundances complicates detection. Multitarget (MT) detection strategies have been developed to increase sensitivity. Yet, empirical evidence supporting performance gains of MT vs. single‐target (ST) strategies in a postoperative setting is limited. We compared ctDNA detection in 379 paired plasma samples from 112 stage II–III colorectal cancer patients by ST digital PCR and MT sequencing of 16 patient‐specific variants. The strategies exhibited good concordance (90%, Cohen''s Kappa 0.79), with highly correlated ctDNA quantifications (Pearson r = 0.985). A difference was observed in ctDNA detection preoperatively (ST 72/92, MT 88/92). However, no difference was observed immediately after surgery in recurrence (ST 11/22, MT 10/22) or nonrecurrence (both 2/34) patients. In serial samples, detection was similar within recurrence (ST 13/16, MT 14/16) and nonrecurrence (ST 3/49, MT 1/49) patients. Both approaches yielded similar lead times to standard‐of‐care radiology (ST 4.0 months, MT 4.1 months). Our findings do not support significant performance gains of the MT strategy over the ST strategy for postoperative ctDNA detection. 相似文献
35.
Chi-Ming Lee Nancy J. Campbell Brian J. Williams Leslie L. Iversen 《European journal of pharmacology》1986,130(3):209-217
Tachykinin binding sites in guinea pig urinary bladder (GPUB), rat salivary gland (RSG), hamster urinary bladder (HUB), rat vas deferens (RVD) and rat cerebral cortex (RCC) were compared using 125I-Bolton Hunter conjugates of substance P (125I-BHSP), eledoisin (125I-BHE) and neurokinin A (125I-BHNKA). In typical SP-P tissues (GPUB, RSG) and in RCC, SP was the most potent displacer of 125I-BHSP and [Glp6, D-Pro9]-SP(6–11) was 90 times less active than [Glp6, L-Pro9]-SP(6–11) while SP methyl ester (SPOMe) was 5–10 times more active than the Bolton Hunter conjugate of SPOMe (I-BHSPOMe). On the other hand, in typical SP-E tissues (HUB, RVD), neurokinin A was most potent in displacing 125I-BHE and [Glp6,D-Pro9]-SP(6–11) was over 300 times more active than [Glp6,L-Pro9]-SP(6–11) while SPOMe was 160 times less active than I-BHSPOMe. In rat cerebral cortex, the rank order of potency of tachykinins and related analogues in displacing 125I-BHE was distinct from that of peripheral SP-E sites, with neurokinin B being the most potent displacer, and SPOMe was over 1 000 times more active than I-BHSPOMe; 125I-BHE binding sites in CNS may represent a third category of tachykinin receptor, designated SP-N. 相似文献
36.
Flow cytometric deoxyribonucleic acid index: a prognostic factor in endometrial carcinoma 总被引:1,自引:0,他引:1
O E Iversen 《American journal of obstetrics and gynecology》1986,155(4):770-776
In a prospective study, flow cytometric deoxyribonucleic acid analyses were performed on cell samples from benign and malignant tumors of the endometrium and benign endometrium. No ploidy aberrations were found in normal endometrium. Of 52 cases with adenocarcinomas, 38 (73%) were diploid and 14 (27%) aneuploid. Both the frequency and the degree of aneuploidy were correlated to histologic tumor grade but not to other prognostic variables such as International Federation of Gynecologists and Obstetricians stage, depth of myometrial invasion, or patient age. Patients with aneuploid tumors had a higher recurrence rate and shorter disease-free intervals as compared to those with diploid tumors. Similarly, death rates were higher and the median survival was shorter in the aneuploid group. Flow cytometric ploidy determination may therefore serve as an important prognostic parameter. 相似文献
37.
A role for receptors of N-methyl-D-aspartic acid in the discriminative stimulus properties of phencyclidine 总被引:4,自引:0,他引:4
M D Tricklebank L Singh R J Oles E H Wong S D Iversen 《European journal of pharmacology》1987,141(3):497-501
Ketamine and (+)-N-allylnormetazocine ((+)-NANM) were found to generalize in a rat operant drug discrimination paradigm to the interoceptive stimulus induced by phencyclidine (PCP). Intraperitoneal administration of the non-competitive antagonist of the N-methyl-D-aspartate (NMDA) receptor, MK-801, and intracerebroventricular injection of the competitive antagonist, 2-DL-amino-7-phosphonoheptanoic acid (2-APH), also resulted in a dose-dependent generalisation to the PCP discriminative stimulus. The results suggest that NMDA receptor antagonism may play an important role in the mediation of the discriminative stimulus properties of PCP. The low potency of MK-801 and 2-APH to displace [3H](+)-NANM binding in vitro argues against an involvement of the haloperidol-sensitive sigma recognition site in the behaviour. 相似文献
38.
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40.
Alison E. Heald Patrick L. Iversen Jay B. Saoud Peter Sazani Jay S. Charleston Tim Axtelle Michael Wong William B. Smith Apinya Vutikullird Edward Kaye 《Antimicrobial agents and chemotherapy》2014,58(11):6639-6647
Two identical single-ascending-dose studies evaluated the safety and pharmacokinetics (PK) of AVI-6002 and AVI-6003, two experimental combinations of phosphorodiamidate morpholino oligomers with positive charges (PMOplus) that target viral mRNA encoding Ebola virus and Marburg virus proteins, respectively. Both AVI-6002 and AVI-6003 were found to suppress disease in virus-infected nonhuman primates in previous studies. AVI-6002 (a combination of AVI-7537 and AVI-7539) or AVI-6003 (a combination of AVI-7287 and AVI-7288) were administered as sequential intravenous (i.v.) infusions of a 1:1 fixed dose ratio of the two subcomponents. In each study, 30 healthy male and female subjects between 18 and 50 years of age were enrolled in six-dose escalation cohorts of five subjects each and received a single i.v. infusion of active study drug (0.005, 0.05, 0.5, 1.5, 3, and 4.5 mg/kg per component) or placebo in a 4:1 ratio. Both AVI-6002 and AVI-6003 were safe and well tolerated at the doses studied. A maximum tolerated dose was not observed in either study. The four chemically similar PMOplus components exhibited generally similar PK profiles. The mean peak plasma concentration and area under the concentration-time curve values of the four components exhibited dose-proportional PK. The estimated plasma half-life of all four components was 2 to 5 h. The safety of the two combinations and the PK of the four components were similar, regardless of the target RNA sequence. 相似文献