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101.
102.
Angiogenesis, the growth of new vessels from existing vasculature, plays an essential role in tumour development. The process involves interaction between a variety of cells, growth factors, and components of the extracellular matrix, regulated by pro-angiogenic and anti-angiogenic factors. This review profiles these factors, outlines the available methods for measuring new vessel formation, and discusses the importance of angiogenesis in breast cancer, with emphasis on ductal carcinoma in situ. 相似文献
103.
Arnaud Bourdin Alberto A. Papi Jonathan Corren J. Christian Virchow Megan S. Rice Yamo Deniz Michel Djandji Paul Rowe Ian D. Pavord 《Allergy》2021,76(1):269-280
Background
Dupilumab blocks the shared receptor component for interleukin (IL)-4/IL-13, key drivers of type 2 inflammation. In phase 2b (NCT01854047) and phase 3 LIBERTY ASTHMA QUEST (NCT02414854), add-on dupilumab 200/300 mg every 2 weeks (q2w) reduced severe exacerbations, improved prebronchodilator (pre-BD) forced expiratory volume in 1 second (FEV1) and quality of life measures, and it was generally well tolerated in patients with uncontrolled, persistent (phase 2b), or moderate-to-severe (phase 3) asthma.Methods
In patients on high-dose inhaled corticosteroids (ICS) with type 2-high asthma (subgroups including baseline blood eosinophils ≥150/300 cells/µL and/or fractional exhaled nitric oxide [FeNO] ≥25 ppb), annualized severe exacerbation rates over the treatment period, changes from baseline in pre-BD FEV1 and asthma control (5-item asthma control questionnaire [ACQ-5]) were analyzed.Results
In high-dose ICS type 2-high subgroups, dupilumab 200/300 mg q2w vs placebo in the phase 2b (24 weeks) and phase 3 (52 weeks) studies significantly reduced severe exacerbations by 55%-69%/57%-60% (all P<.05) and 53%-69%/48%-66% (all P < .001), respectively, except in patients with ≥ 300 eosinophils/µL in phase 2b study (24%/50% (P = .52/0.15). Across subgroups, pre-BD FEV1 improved by 0.18-0.22 L/0.19-0.24 L (all P < .05) and 0.23-0.36 L/0.15-0.25 L (all P < .01) and ACQ-5 scores were reduced by 0.46-0.55/0.47-0.85 (all P < .05) and 0.38-0.50/0.24-0.30 (all P < .05), respectively, except dupilumab 200 mg q2w in phase 2b in patients with FeNO ≥ 25 ppb (0.41; P = .09). Dupilumab was also effective in patients taking medium-dose ICS.Conclusion
Dupilumab significantly reduced severe exacerbations and improved lung function and asthma control in patients with type 2-high asthma on high-dose ICS at baseline.104.
Kathleen R. Ambrose Dennis E. Rice Mark M. Goodman F. F. Knapp Jr. 《European journal of nuclear medicine and molecular imaging》1987,13(7):374-379
The metabolism of two new 3-methyl-branched iodovinyl fatty acids in rat hearts was evaluated by determining the subcellular and lipid pool distribution of these radiolabeled analogues after intravenous injection. Methyl branching had been introduced into the straight chain analogue, 19-iodo-18-nonadecenoic acid (IVN), to produce the monomethyl analogue, 19-iodo-3-(R,S)-methyl-18-nonadecenoic acid (BMIVN) and the dimethyl derivative, 19-iodo-3,3-dimethyl-18-nonadecenoic acid (DMIVN) in the hope of inhibiting oxidation. Since the presence of 3-methyl branching results in delayed myocardial clearance in rats, differences were sought in the lipid and subcellular distribution of these branched analogues that might correlate with the prolonged retention and reflect differences in metabolism. Hearts of rats injected intravenously with the radiolabeled fatty acids were removed and homogenized and the homogenates partitioned between the chloroform-methanol (organic) fraction and the aqueous fraction. Comparison of the distribution of radioactivity between the organic and aqueous fractions showed that most of the DMIVN and BMIVN activity was in the organic fraction with IVN activity initially divided equally between the two fractions. Identification of the lipid components of these organic fractions showed that there was slow incorporation of DMIVN into the triglyceride and polar lipid fractions with a slow loss from the free fatty acid fraction. With the straight chain IVN analogue which shows rapid washout from rat hearts, there was loss of activity from all 3 lipid components during the 60 min. The monomethyl branched BMIVN analogue demonstrated predominant storage in the polar lipid fraction with some incorporation into triglycerides. Subcellular distribution studies of the three analogues also showed differences that correlated with the observed differences in heart retention properties. With the unbranched IVN analogue, radioactivity was found primarily in the cytoplasmic fraction 30 min after injection, whereas the branched analogues demonstrated a much higher association with the microsomal and mitochondrial fractions of the heart. In rats fed prior to injection, these differences in the subcellular distribution profiles were minimized. The lipid and subcellular distribution patterns reported here for the methyl branched analogues as compared to those of the straight chain iodovinyl fatty acid may provide some understanding as to the mechanisms of retention in rat myocardium.Research supported by the Office of Health and Environmental Research, U.S. Department of Energy, under contract DE-AC0 5-840 R21400 with Martin Marietta Energy Systems, Inc. 相似文献
105.
Breast cancer detection: one versus two views 总被引:2,自引:0,他引:2
Mammographic examinations of 169 patients with 172 biopsy-proved carcinomas, and of 194 healthy subjects, were interpreted independently and retrospectively by three experienced mammographers, initially as single-view oblique examinations and 6 months later as two-view oblique-cephalocaudal examinations. For the single-view examinations of the cancer patients, 67% of the cancers were correctly recommended for biopsy, additional views were requested for 23%, and a "negative" interpretation was made for 10%. For the single-view examinations of healthy subjects, biopsy was recommended for 7% and additional views were recommended for 32%. For the two-view examinations of women with cancer, 80% of the cancers were correctly recommended for biopsy, additional views were requested for 4%, and a "negative" interpretation was made for 16%. For two-view examinations of healthy subjects, biopsy was recommended for 7% and additional views were requested for only 5%. The authors conclude that single-view screening should not be performed, because it would lead to an excessive number of "call-back" examinations of healthy patients, producing additional cost and anxiety that would outweigh any theoretical benefit. 相似文献
106.
An economic assessment of health care coverage for the elderly 总被引:1,自引:0,他引:1
T Rice 《The Milbank quarterly》1987,65(4):488-520
The current array of public and private health care coverages for the elderly is so complex and confusing that consumers are unable to make effective choices. The recent "medigap market" still further confounds the operation of "economic efficiency" in competitive insurance markets; consumers are uninformed about the extent and value of their basic coverage and even more so about the vulnerabilities against which supplementary insurance is purchased. This structural impediment to effectiveness and efficiency is most critical for long-term nursing care. Future changes in public programs must recognize that comprehensive benefits must also be made comprehensible. 相似文献
107.
G D Harpur R Suke B H Bass M J Bass S B Bull L Reese J H Noseworthy G P Rice G C Ebers 《Neurology》1986,36(7):988-991
We carried out a randomized, double-blind, placebo-controlled trial of hyperbaric oxygen therapy (HBO) in patients with chronic stable MS. Eighty-two patients were treated in a multiplace hyperbaric chamber with gas supplied by mask. Forty-one patients received 20 consecutive daily treatments of 100% O2 followed by 7 "booster" treatments in the next 6 months; 41 control patients received "air" (12.5% O2 at 1.75 atmospheres absolute). There was no significant difference in treatment and control groups in the Extended Kurtzke Disability scores, Kurtzke Functional scores, magnetic resonance imaging, or evoked potentials after the initial 20 treatments or after the boosters. HBO is not effective in treating chronic stable MS. 相似文献
108.
109.
The toxicity of copper to the adult and early life stages of the freshwater clam,Corbicula manilensis 总被引:1,自引:0,他引:1
Florence L. Harrison John P. Knezovich David W. Rice Jr. 《Archives of environmental contamination and toxicology》1984,13(1):85-92
The copper sensitivity of adult and larval stages of the freshwater clamCorbicula manilensis was evaluated. In addition, copper concentrations were determined in adult clams exposed for 4 to 10 weeks to copper in a high-volume, flow-through bioassay. All bioassay systems utilized water that was low in total hardness and alkalinity.The response of the clams to copper depended on life stage. Copper sensitivity of larvae decreased markedly in successive developmental stages. LC5024's of veliger and juvenile larvae were 28 and 600 g Cu/L, respectively. The mortality of trochophore larvae exposed to 10 g Cu/L for one hr was 91.5%. The sensitivity to copper decreased with increased amounts of larval shell deposition.Adult clams were resistant to copper; the LC5096 was greater than 2,600 g Cu/L. By comparison, the incipient lethal concentration (ILC, was lowless than 10 g Cu/L. Adult clams accumulated more copper as concentrations in the water increased. Evidence was obtained for copper loss near or at death.Labile and total copper, as well as the coppercomplexing capacity, in the bioassay water were determined; the majority of copper was present as labile species. Toxicity was related to the quantities of labile copper in the water.This work was supported by the U.S. Nuclear Regulatory Commission (Memorandum of Understanding with the U.S. Department of Energy) and by the U.S. Department of Energy (contract number W-7405-ENG-48). 相似文献
110.
San Lazaro Campillo Indra Meaney Sarah Sheehan Jacqueline Rice Rachel O’Donoghue Keelin 《Maternal and child health journal》2021,25(2):282-292
Maternal and Child Health Journal - To assess university students’ knowledge of reproductive health information about miscarriage. A single-centre, cross-sectional study was carried out using... 相似文献