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排序方式: 共有657条查询结果,搜索用时 46 毫秒
1.
可逆性胆硷酯酶抑制剂二甲氨基甲酸-5-二氢吲哚酯的合成 总被引:1,自引:0,他引:1
为了深入研究催醒宁类化合物的结构与抑酶活性的关系,设计合成了-系列1-,3-或5-位不同取代的二氢吲哚类衍生物(中间体和终产物共24个新化合物)。中间体1,3-二甲基-5-烷氧基-2-二氢吲哚酮(A)的C3烷化。采用相转移催化方法进行;反应中还分离到三个副产物(Ⅶ~Ⅸ)。初筛结果表明:这些化合物大多有较强的抑酶活性;1,3-或5-位取代基的改变均明显影响其活性。 相似文献
2.
Braffman BH; Coleman BG; Ramchandani P; Arger PH; Nodine CF; Dinsmore BJ; Louie A; Betsch SE 《Radiology》1994,190(3):797
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4.
Debbie Ehrmann Feldman Mirella de Civita Patricia L. Dobkin Pete Malleson Garbis Meshefedjian CiarÁn M. Duffy 《Arthritis care & research》2007,57(2):226-233
Objective
To document perceived adherence to treatment (taking medications and performing exercises) in patients with juvenile idiopathic arthritis (JIA) over a 1‐year period and to identify related factors.Methods
We surveyed parents of patients with JIA at the Montreal Children's Hospital and British Columbia's Children's Hospital in Vancouver. Parents were asked to respond to a series of questionnaires every 3 months over a 12‐month period. Perceived adherence was evaluated on a 100‐mm visual analog scale (VAS) in the Parent Adherence Report Questionnaire (PARQ). Parental coping, distress, child function, disease severity and duration, perceived helpfulness of treatment, problems encountered, and sociodemographic data were also assessed.Results
The mean age of our sample of 175 children was 10.2 years; mean age at diagnosis was 6.1 years and mean disease duration was 4.1 years. Perceived adherence to medications was consistently high, with average adherence at baseline, 3, 6, 9, and 12 months being 86.1, 91.7, 90.4, 92.0, and 88.8, respectively, on the PARQ VAS. Perceived adherence to exercise was lower but remained steady, with corresponding means of 54.5, 64.1, 61.2, 63.0, and 54.3, respectively. Using generalized estimating equation analysis, factors associated with higher perceived adherence to medications included perceived helpfulness of medications and lower disease severity; those associated with higher perceived adherence to exercise were younger age of the child, child involvement in responsibility for treatment, and higher perceived helpfulness of the treatment.Conclusion
Belief in helpfulness of treatment is associated with higher parental perceived adherence to treatment. 相似文献5.
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7.
The gap effect and inhibition of return: interactive effects on eye movement latencies 总被引:2,自引:0,他引:2
Richard A. Abrams Richard S. Dobkin 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1994,98(3):483-487
Three experiments are reported with two types of manipulations that are known to affect the latency with which subjects can initiate saccadic eye movements. The first manipulation involves the temporal relation between the offset of a visual fixation point and the onset of a peripheral target (the gap effect). The second manipulation involves the prior allocation and removal of visual attention (inhibition of return). In two experiments, the gap effect was smaller for saccades to previously attended locations than to previously unattended locations. The results suggest an important link between the two phenomena and provide new insights into the brain mechanisms underlying visual attention and eye movements. 相似文献
8.
Sarah L. Nolin Anne Glicksman Nicole Tortora Emily Allen James Macpherson Montserrat Mila Angela M. Vianna‐Morgante Stephanie L. Sherman Carl Dobkin Gary J. Latham Andrew G. Hadd 《American journal of medical genetics. Part A》2019,179(7):1148-1156
Instability of the FMR1 repeat, commonly observed in transmissions of premutation alleles (55–200 repeats), is influenced by the size of the repeat, its internal structure and the sex of the transmitting parent. We assessed these three factors in unstable transmissions of 14/3,335 normal (~5 to 44 repeats), 54/293 intermediate (45–54 repeats), and 1561/1,880 premutation alleles. While most unstable transmissions led to expansions, contractions to smaller repeats were observed in all size classes. For normal alleles, instability was more frequent in paternal transmissions and in alleles with long 3′ uninterrupted repeat lengths. For premutation alleles, contractions also occurred more often in paternal than maternal transmissions and the frequency of paternal contractions increased linearly with repeat size. All paternal premutation allele contractions were transmitted as premutation alleles, but maternal premutation allele contractions were transmitted as premutation, intermediate, or normal alleles. The eight losses of AGG interruptions in the FMR1 repeat occurred exclusively in contractions of maternal premutation alleles. We propose a refined model of FMR1 repeat progression from normal to premutation size and suggest that most normal alleles without AGG interruptions are derived from contractions of maternal premutation alleles. 相似文献
9.
This study was designed to determine whether the somatostatin analogue,
octreotide, could prevent embryonic loss by normalizing increased uterine
insulin-like growth factor-I (IGF-I) action related to hyperoestrogenaemia
following superovulation. Superovulated immature and
oestradiol-17beta-treated adult rats were infused with 100 or 300 microg/ml
of octreotide respectively, or injected daily with 1 or 10 microg of
octreotide from day 1 to day 3 of pregnancy. On day 3, embryos were
collected from the oviducts and uteri. Uterine luminal fluid was subjected
to embryo culture. The amounts of uterine IGF-I and IGF binding proteins
(IGFBP) were determined by radioimmunoassay and ligand binding assay
respectively. Octreotide infusion normalized uterine IGF-I action following
superovulatory and oestradiol-17beta treatment, by reducing IGF-I
concentrations and increasing IGFBP concentrations. Octreotide infusion
increased the number of normal embryos by 2.7-fold and 1.7-fold in
superovulated and oestradiol-17beta- treated rats respectively, and
reversed the detrimental effects of uterine luminal fluid on embryonic
development caused by superovulatory and oestradiol-17beta treatment. Daily
injections with octreotide had similar but reduced effects in all
parameters examined in both treatment groups. In conclusion, octreotide may
reduce embryonic loss, at least in part, by normalizing IGF-I action
following superovulation.
相似文献
10.
Resurgent tuberculosis in New York City. Human immunodeficiency virus, homelessness, and the decline of tuberculosis control programs 总被引:34,自引:0,他引:34
The resurgence of tuberculosis in New York City has been largely attributed to the acquired immune deficiency syndrome (AIDS) epidemic. However, historical events predating the advent of AIDS and worsening economic and social conditions, including a rise in homelessness, have contributed significantly to the increase. We prospectively studied 224 consecutive patients with tuberculosis admitted to a large public hospital in New York over the first 9 months of 1988. Initial assessment included medical status, human immunodeficiency virus (HIV) risk factors, and detailed social information, including substance abuse history and housing status. All patients were tracked after discharge to determine compliance and cure rates. Tuberculosis patients were predominantly male (79%), with high rates of alcohol use (53%), intravenous drug and/or "crack" cocaine use (64%), and homelessness or unstable housing (68%). Half the patients had AIDS or AIDS-related complex (ARC) or were HIV antibody positive. A total of 178 patients were discharged on tuberculosis treatment, but 89% of these were lost to follow-up and failed to complete therapy. Of the 178 discharged patients, 48(27%) were readmitted within 12 months with confirmed active tuberculosis. Of these patients, 40 were discharged on treatment and at least 35 were again lost to follow-up. In a multivariate regression model noncompliance was significantly associated with the absence of AIDS or ARC (p less than 0.001), homelessness (p less than 0.005), and alcoholism (p less than 0.05). Because HIV infection and tuberculosis converge in a subpopulation with high rates of substance abuse and homelessness, the problem of ensuring treatment compliance may grow considerably in the future.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献