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991.
992.
The development of hand preference in infant reaching is marked by several lateral fluctuations. This study investigated whether similar lateral fluctuations were present in infants' spontaneous, nonreaching, and freely performed movements. We collected reaching and nonreaching movements kinematics in 4 infants that we followed longitudinally during their 1st year. In their 4th year, we assessed the direction of their hand preference. We found that lateral biases in spontaneous, nonreaching movements in the 1st year showed several shifts that were similar to those observed in reaching. Despite these shifts, all 4 infants traversed a short period of right-handedness. This right-handedness matched the direction of their hand preference at 3 years of age. We propose that shifts in the development of hand preference in the 1st year are linked to successive reorganizations of the motor system. These reorganizations take place as infants learn to sit, crawl, and walk. 相似文献
993.
Summary— Contractile responses evoked by the 5-HT1B/D receptor agonists, dihydroergotamine, naratriptan and sumatriptan, were compared in canine isolated coronary artery rings before and after endothelial dysfunction as obtained by inhibition of nitric oxide synthase with Nω-nitro-L-arginine methyl ester (L-NAME; 10 μM). The three agonists contracted rings in the potency order of dihydroergotamine (geometric mean pD2 value with 95% confidence limits in parentheses: 6.9 [5.3–7.9] and 7.0 [5.4–7.3] in the absence and presence of nitric oxide synthase (NOS) inhibition [I], respectively) ≥ naratriptan (6.8 [5.7–7.3] and 6.4 [5.7–6.6]) > sumatriptan (4.8 [3.6–5.6] and 5.0 [3.6–5.6]) independently of the presence or absence of L-NAME. In absence of L-NAME, efficacy, as assessed by the mean maximal contractile response (Emax), tended to be greater, although not significantly, for sumatriptan and naratriptan compared to dihydroergotamine. L-NAME per se markedly increased developed tension (43.0 ± 4.6 mN; n = 50) and potentiated maximal responses (0.6 ± 0.2 and 10.7 ± 2.4 mN for dihydroergotamine in the absence and presence of L-NAME respectively; 1.7 ± 0.6 and 18.7 ± 3.7 mN for naratriptan; 2.5 ± 0.6 and 21.3 ± 3.8 mN for sumatriptan; P < 0.01 in each case). Emax values of sumatriptan and naratriptan were greater than those produced by dihydroergotamine in the presence of L-NAME but remained lower than the sub-maximal contractile responses evoked by the thromboxane A2 analogue, U-46619 (ie, 32.4 ± 5.2 mN in the absence of L-NAME; n = 50), or L-NAME per se. In conclusion, 5-HT1B/D receptor agonist efficacies in contracting coronary arteries are relatively low under basal conditions and are potentiated in the presence of a dysfunctional endothelium, whereas agonist potencies remain unaffected. 相似文献
994.
苦参碱对细菌脂多糖诱导大鼠枯否细胞释放肿瘤坏死因子及白细胞介素-6的影响 总被引:34,自引:1,他引:33
目的是研究苦参碱对细菌脂多糖(lipopolysachrides,LPS)诱导经卡西霉素(calcimycin,Cal)预激活的大鼠枯否细胞分泌肿瘤坏死因子(tumor necrosis factor,TNF)、白细胞介素-6(interleukin-6,IL-6)的影响以及对小鼠体内产生TNF和IL-6的影响。结果,苦参碱125,250及500mg·L-1剂量依赖性抑制大鼠枯否细胞分泌TNF和IL-6;苦参碱50及100mg·kg-1降低小鼠体内TNF和IL-6的水平。提示苦参碱的抗炎作用可能与其抑制TNF及IL-6的产生有关。 相似文献
995.
Delchier JC Elamine I Goldfain D Chaussade S Barthelemy P Idstrom JP 《Alimentary pharmacology & therapeutics》1996,10(3):263-268
AIM: To assess the effect of adding clarithromycin to the combination of omeprazole and amoxycillin for the eradication of H. pylori infection. PATIENTS AND METHODS: In an open, randomized, three-centre study 120 patients (69 men, mean age 47 years, caucasians 74%) with symptoms of dyspepsia had normal gastroscopic examination and a positive urease test. They underwent a 13C-urea breath test and received, for 14 days, either omeprazole 40 mg b.d. plus amoxycillin 750 mg b.d., or the same regimen plus clarithromycin 250 mg b.d. Compliance was assessed by returned tablet counts. H. pylori clearance at the end of treatment and eradication 4 weeks after finishing treatment were assessed by 13C-urea breath test. RESULTS: Results are expressed according to 'all patients treated analysis', excluding patients who did not receive treatment and patients who had no final 13C-urea breath test assessment. In the groups treated with omeprazole- amoxycillin or omeprazole-amoxycillin-clarithromycin good compliance (> or = 90%) was observed in 85% vs. 76% (N.S.) of patients but 25% vs. 34% (N.S.) experienced at least one adverse event. Adverse events were minor, and no patient reported a metallic taste. Four weeks after finishing treatment eradication rates were 26% (95% CI: 15-37%) vs. 93% (95% CI: 86-99%) (P < 0.001). CONCLUSION: These results show that dual therapy with omeprazole plus amoxycillin achieves an unacceptably low H. pylori eradication rate. Addition of clarithromycin at low dosage (250 mg b.d.) proved to be useful, achieving a high eradication rate without increasing side-effects. 相似文献
996.
There is clear evidence for a cancer cure. The hypothesis behind a treatment with curative intent is the ability to eradicate all the cancer cells of a tumour. Out of three cancer deaths, one is related to local failure. In some cancers like breast carcinoma, death is mainly in relation with the development of distant metastases. Even in such a tumour, an improvement in local control can translate as better survival. Radiationtherapy, often in association with surgery, is playing a major role in tumour local control. Such a local control is mandatory if cure is at aim. One of the main goals of clinical research is to find a good compromise between local control of the disease and a non mutilating surgical approach. 相似文献
997.
Lazarus P; Sheikh SN; Ren Q; Schantz SP; Stern JC; Richie JP Jr; Park JY 《Carcinogenesis》1998,19(3):509-514
Inactivation of tumor suppressor genes like p53 and p16 play a key role in
tumor progression, with a high incidence of mutations existing for both
genes in oral squamous cell carcinomas. Previous studies have demonstrated,
(i) a correlation between the prevalence of p53 mutations and tobacco use
[Brennan et al. (1995) New Engl. J. Med., 332, 712-717; Lazarus et al.
(1996) Carcinogenesis, 17, 733-739], and (ii) a link between genotypes in
specific xenobiotic metabolizing enzymes and oral cancer susceptibility
[Park et al. (1997) Cancer Epid. Biomarkers Prev., 6, 791-797). In this
paper, we present results of our examination of a series of 80 oral
squamous cell carcinomas for p53 exons 5-9 and p16 exons 1-2 mutations, and
the potential association of these mutations with specific genotyping
patterns. p53 mutation prevalence in oral tumors was linked with increased
patient tobacco use using several stratification criteria. There was a
significantly higher prevalence of p53 mutations in OCSCCs from patients
who smoked > 30 pack-years as compared to tumors from patients who
smoked < or = 30 pack-years (OR = 2.8; CI = 1.1-7.2). No significant
association was observed with patient alcohol consumption. There was a
significant association between the prevalence of p53 mutations in oral
tumors and CYP1A1 genotyping patterns in these oral cancer patients, with
the highest p53 mutation prevalence observed in subjects with the CYP1A1
[val]/GSTM1 [+] genotype (OR = 6.0; CI = 1.2-29.7). A significant
association was not observed between the prevalence of p16 mutations in
oral tumors and tobacco use, or CYP1A1 [val] or GSTM1 (0/0) genotypes.
These data suggest that the induction of mutations in specific tumor
suppressor genes or oncogenes in oral tumors may be associated with
specific carcinogen exposures, and that this association may be linked to
specific polymorphic genotypes in xenobiotic-metabolizing enzyme genes.
相似文献
998.
Popliteal vascular disease: evaluation with spiral CT angiography 总被引:11,自引:0,他引:11
Beregi JP; Djabbari M; Desmoucelle F; Willoteaux S; Wattinne L; Louvegny S 《Radiology》1997,203(2):477
999.
1000.
B Torres-Álvarez JP Castanedo-Cazares C Fuentes-Ahumada B Moncada 《Journal of the European Academy of Dermatology and Venereology》2007,21(3):334-339
BACKGROUND: The mechanism of the action of methotrexate (MTX) in the treatment of psoriasis has not been completely elucidated. OBJECTIVE: To assess the effect of MTX on the expression of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin, activation molecule CD69 and T-cell phenotype in skin specimens from patients with psoriasis. METHODS: We performed an immunohistochemical analysis of the expression of T-cell phenotype and cell adhesion/activation molecules in skin biopsies from patients with psoriasis treated with a fixed dose of MTX (12.5 mg/week). To determine data on the epidermal/dermal T-cell infiltration we carried out a manual quantification. RESULTS: Skin samples prior to therapy showed a moderate to severe inflammatory infiltrate, mainly due to T lymphocytes with a helper/inducer (CD4) phenotype. Most of these cells also expressed ICAM-1 and VCAM-1. Blood vessels showed expression of E-selectin and VCAM-1, and keratinocytes were positive for ICAM-1 staining. The cell infiltrate was reduced after therapy, as well as the expression of cell adhesion molecules. However, we also noted the persistence of the T lymphocyte phenotype CD8(+), expressing the CD69 activation molecule, after the MTX treatment. CONCLUSIONS: MTX downregulates the expression of some adhesion molecules, a phenomenon that may contribute to its anti-inflammatory therapeutic effect in psoriasis. The infiltrating T cells post-treatment have an activated cytotoxic phenotype, which may suggest a pathogenic role in the continuation and/or recurrence of psoriasis. 相似文献