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排序方式: 共有650条查询结果,搜索用时 31 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
3.
Moderation of physiological stress responses by personality traits and daily hassles: less flexibility of immune system responses 总被引:1,自引:0,他引:1
Previously we demonstrated that stressors varying on the dimension of mental effort and controllability have distinctive effects on cardiovascular, endocrine and immune system responses. The purpose of the present study was to relate individual differences in physiological stress responsivity to task appraisal and stress-induced mood changes (issue 1), trait characteristics (issue 2) and daily hassles (issue 3). Appraisal and mood changes did not mediate the differential effects of the stressors. The trait characteristics, aggression and external locus of control and daily hassles moderated the effect of the stressor on physiological parameters, especially immune parameters. Moreover, the moderation effect was different in the high versus the low effort stress task. High aggression, high external locus of control and more daily hassles were associated with increased reactivity in the low effort condition and decreased reactivity in the high effort condition, which is suggested to reflect less differentiated responding to changing task demands and hence, less flexibility in the immune system. 相似文献
4.
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
5.
Regulation of B Cell Activity in Man: Role of T Cells 总被引:15,自引:0,他引:15
Rudy E. Ballieux Cobi J. Heijnen Fons Uytdehaag Ben J. M. Zegers 《Immunological reviews》1979,45(1):3-39
6.
Characterization of human T suppressor-inducer, -precursor and -effector lymphocytes in the antigen-specific plaque-forming cell response 总被引:6,自引:0,他引:6
Suppression of an antigen-specific plaque-forming cell response of human blood lymphocytes can be effected by T mu+ cells that have been primed previously by antigen in vitro for 6 days. While lacking the capacity to suppress the plaque-forming response directly, these primed T mu+ suppressor-inducer cells stimulate a subpopulation of unprimed T mu gamma- cells to differentiate to T gamma + suppressor-effector cells. The T mu+, T gamma+ and T mu gamma- subsets have been shown to be heterogeneous populations of cells. Therefore, the functionally defined T suppressor-inducer, -precursor and -effector cells were characterized by OKT monoclonal antibodies and by the capacity to form rosettes with autologous erythrocytes (ar+). Evidence will be presented that in vitro a T4+mu+ar- cell induces a T8+mu gamma-ar+ precursor cell to differentiate to a T8+gamma+ar- suppressor-effector cell. A similar T suppressor-effector cell can also be isolated directly from peripheral blood of normal donors. 相似文献
7.
Rouppe van der Voort C Kavelaars A van de Pol M Heijnen CJ 《Journal of neuroimmunology》1999,95(1-2):165-173
Beta2- and alpha2-adrenergic receptors (AR) are thought to be the main AR subtypes to exert the effects of catecholamines on the immune system. However, in the present study, we demonstrate that another subtype of AR can be induced in human monocytes. Expression of alpha1b- and alpha1d-AR mRNA can be obtained by culturing freshly isolated human peripheral blood monocytes with the neuroendocrine mediators dexamethasone or the beta2-AR agonist terbutaline. Using the human monocytic cell line THP-1, we demonstrate that increased levels of alpha1b- and alpha1d-mRNA are accompanied by increased levels of receptor protein as determined by Western blot analysis and radioligand binding assays. This study describes for the first time regulated expression of alpha1-AR subtypes in human monocytes. 相似文献
8.
S Bydder NA Spry DRH Christie D Roos BH Burmeister H Krawitz S Davis DJ Joseph M Poulsen M Berry 《Journal of Medical Imaging and Radiation Oncology》2003,47(3):284-288
The purpose of this study was to prospectively examine the effectiveness and tolerability of a simple radiotherapy technique for the palliation of symptomatic liver metastases. Twenty‐eight patients with symptomatic liver metastases were enrolled from seven centres, and received targeted (partial or whole) liver irradiation consisting of 10 Gy in two fractions over 2 days. Symptoms at baseline were hepatic pain (27 patients), abdominal distension (19), night sweats (12), nausea (18) and vomiting (eight). Twenty‐two patients (76%) had failed previous treatment with chemotherapy, hormonal therapy and/or high‐dose steroids. Symptoms and potential toxicities were prospectively assessed at the time of treatment, then 2, 6 and 10 weeks later. Individual symptom response rates were 53?66% at 2 weeks. Partial or complete global symptomatic responses were noted in 15 patients (54%) overall. The treatment was well tolerated with two patients (7%) experiencing grade 3 toxicity (one vomiting and one diarrhoea); however, four patients reported temporary worsening of pain shortly after treatment. This simple and well‐tolerated treatment achieves useful palliation. 相似文献
9.
10.
I. C. M. Heijnen R. J. P. Franken B. J. W. Bevaart 《Disability and rehabilitation》2013,35(9):675-678
Background. Spastic hemiplegia is a common feature after stroke, which can result in a clenched fist deformity with secondary hygienic problems and pain. Operative treatment can improve these problems, although literature about its long-term effects is lacking.Purpose. To determine whether Superficialis-to-Profundus tendon (StP-) transfer procedure leads to permanent improvement of hygiene and reduction of pain in patients with clenched fist due to spastic hemiplegia following stroke.Method. Patients who underwent a StP-transfer in 2003 – 2005 were evaluated on skin condition, upper extremity joint mobility, resting position and muscle tone and with VAS scores on hygiene maintenance and pain in the hand.Results. Six patients (mean age 54 years; duration after stroke 10 years) were included. Indications to operate were hygienic problems only (3) or combined with pain (3). The average follow-up period was 19 months. After 6 weeks of post-operative splinting, no standard follow-up was applied. Serious post-operative complications were not reported. At follow-up no hygienic problems were present and pain was decreased in all except one patient. All hands could passively be fully opened. In resting position, flexion was seen in the MCP-joints (60 – 90°). Muscle tone was raised in flexors of the wrist and fingers and m. adductor pollicis (Ashworth 1 – 2). Given the same pre- and post-operative circumstances, all patients would agree to have the surgery over again.Conclusion. Even 19 months after the StP-transfer for clenched fist, all operated hands could still be fully opened and there was a permanent improvement of hygiene and pain reduction. 相似文献