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11.
Nitrergic and peptidergic innervation in the developing rat heart   总被引:1,自引:0,他引:1  
The phenotypic expression and anatomic distribution of nitrergic and peptidergic innervation in the developing rat heart was localized by reduced nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) histochemistry and immunohistochemistry using antibodies against neuronal isoform of nitric oxide synthase (nNOS), neuropeptide Y (NPY) and calcitonin-gene-related peptide (CGRP). NPY-immunoreactive nerve fibers showed the earliest expression by 16 days of gestation, with preferential innervation of the nodal and perinodal areas, followed by the innervation of the valves and ventricles by postnatal day 7. NPY immunoreactivity was also localized to a large proportion of the intrinsic cardiac ganglia from 16 days of gestation onwards with a progressive increase in the number of neuronal cell bodies per ganglia with age. CGRP-positive nerve fibers appeared by 19 days of gestation and were less dense during the gestational and early postnatal periods, and showed a quantitative increase in density by 7 days, followed by a decrease by 3 weeks postnatal. None of the intrinsic ganglia were stained positive for CGRP, indicating the extrinsic sensory origin of these stained fibers. Nitrergic innervation paralleled the sensory innervation, with the cardiac ganglia and nerve fibers showing a positive labeling from 19 days of gestation onwards. NADPH-d and nNOS were partially co-localized. Double-label immunohistochemistry showed that a considerable proportion of sensory CGRP-immunopositive fibers were also immunoreactive for NOS. The results of the present study show that neuropeptides and nitric oxide are expressed by the late gestational period and that autonomic efferent innervation precedes sensory and nitrergic innervation in the developing heart. Accepted: 4 January 2000  相似文献   
12.

Objective

Health information-seeking behaviors (HISBs) are associated with active participation in cancer care decisions which, in turn, may positively impact health outcomes. The goal of this study was to develop a taxonomy of topics for which post-treatment cancer patients sought information, and to explore HISB patterns by sociodemographic factors and cancer type.

Methods

We examined how health information seeking is associated with social determinants in a survey of 521 post-treatment cancer patients.

Results

Four major topics of interest were found: disease/treatment, self-care management, health services, and work/finance. Assessment of the relationship between social determinants and these four topics showed associations for (1) HISBs on disease/treatment topics decreased with age and increased with education; (2) HISBs on self-care management increased with education and varied by cancer type; (3) HISBs on health services increased with education; and (4) HISBs on work/finance decreased with age and wealth, but increased with debt.

Conclusion

These results demonstrate one pathway through which social determinants may drive communication inequalities, which may result in increased disparities in health outcomes.

Practice implications

Further exploration of the relationship between social determinants and information-seeking among post-treatment cancer patients may contribute to the development of strategies to reduce health disparities.  相似文献   
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Early detection has a central role in the prevention and management of mental retardation. The purpose of this present study is to delinerate the characteristics of developmentally delayed infants and their families attending Mental Retardation Clinic. The sample consisted of 101 infants who were registered in Mental Retardation Clinic of NIMHANS, Bangalore in 1988 constituting 12.5% of total registrations. Data was collected from case records. Majority of subjects were males, first or second born, 7 months or older, from a consanguineous lower or middle class family. Along with developmental delay, 60% had other complaints. Medical problems were reported in about half of the subjects and most had abnormalities on physical examination. Aetiology was discernible in 77.1%. Majority had associated physical disorder such as cerebral palsy, seizures and hearing and/or visual impairment. Around 17% came for follow-up thrice or more, 43% dropped out after work-up. The main conclusions are that; (i) certain socio-demographic, personal and clinical variables influence treatment seeking, and (ii) developmental delay recognised in infancy tends to be associated with clear aetiologic factors and significant medical/neurologic problems.  相似文献   
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阿魏酸钠对花生四烯酸代谢的影响   总被引:10,自引:0,他引:10  
利用放射薄层方法测定兔血小板花生四烯酸代谢产物TXB2,PGE2和PGF。用放射免疫法测定兔血小板TXB2及主动脉6-keto-PGF。阿魏酸钠(SF,0.1~3.2 mmol/L),抑制14C-花生四烯酸转化为TXB2,呈剂量效应关系,IC50为0.762 mmol/L。SF在较高浓度(0.8~3.2mmol/L)时亦抑制PGE2,PGF的生成。用放免法观察到,SF对血小板TXB2和动脉壁6-keto-PGF的生成均有抑制作用,对TXB2的作用较强。结果提示,SF可抑制兔血小板和动脉壁环氧酶活性。  相似文献   
18.
The study investigates the need for instruction and support among wives of patients with myocardial infarction, applying the 'stress' theory. The data were gathered by questionnaires completed by 59 wives of patients with myocardial infarction. Feelings and symptoms indicative of stress did occur among wives of the patients. They assessed instruction especially concerning home care, as being inadequate. They stated that the support they received had come largely from their own relatives; more than one third of the respondents said they had received support from a nurse; one fifth said they had not received it from anyone. The 'instruction' model for wives and other relatives of patients with myocardial infarction, introduced at the end of the article, emphasizes the importance of relevant information and support to the close relatives of patients with myocardial infarction.  相似文献   
19.
Genome-wide Association Studies (GWAS) revealed novel genetic markers for breast cancer susceptibility. But little is known about the risk factors and molecular events associated with breast cancer in Arab Population. Therefore, we designed a broad study to investigate the susceptibility and prognostic implications of the GWAS breast cancer loci in the Tunisian population. In a cohort of 640 unrelated patients with breast cancer and 371 healthy control subjects, we characterized the variation of 9 single nucleotide polymorphisms (SNPs), namely rs1219648, rs2981582; rs8051542, rs12443621, and rs3803662; rs889312; rs3817198; rs13387042 and rs13281615. Only 5 out of 9 GWAS breast cancer loci were found to be significantly associated with breast cancer in Tunisians: The rs1219648 (G vs. A allele: OR?=?1.36, P?=?1?×?10(-3)) and rs2981582 (A vs. G allele: OR?=?1.55, P?=?3?×?10(-6)) of FGFR2 gene; the rs8051542 of the TNRC9 gene (T vs. C allele: OR?=?1.40, P?=?4?×?10(-4)); the rs889312 of the MAP3K1 gene (C vs. A allele: OR?=?1.33, P?=?3?×?10(-3)) and the rs13281615 located on 8q24 (G vs. A allele: OR?=?1.21, P?=?0.03). Homozygous variant genotypes of rs2981582 were strongly related to lymph node negative breast cancer (OR?=?3.33, P?=?6?×?10(-7)) and the minor allele of rs2981582 was associated with increased risk of ER+ tumors (OR?=?1.57, P?=?0.02; OR?=?2.15, P?=?0.001, for heterozygous and homozygous variant genotypes, respectively) and increased risk of distant metastasis development (OR?=?2.30, P?=?4?×?10(-3); OR?=?3.57, P?=?6?×?10(-5), for heterozygous and homozygous variant genotypes, respectively) in a dose dependent manner. The association for rs8051542 was stronger for high-grade SBR tumors (OR?=?2.54, P?=?2?×?10(-4)). GG genotype of rs13387042 on 2q35 showed a significant association with the risk of developing distant metastasis (OR?=?1.94, P?=?0.02). The G allele of rs1219648 in FGFR2 and the A allele of rs13387042 on 2q35 indicated a better prognosis by showing a significantly higher overall survival rates (P?=?0.013 and P?=?0.005, respectively). In conclusion, GWAS breast cancer FGFR2, TNRC9, MAP3K1, and 8q24 loci are associated with an increased risk of breast cancer and genetic variation in FGFR2 gene may predict the aggressiveness of breast cancer in Tunisians.  相似文献   
20.
目的:观察白藜芦醇对豚鼠、小鼠和家兔离体心肌收缩力和心率的影响。方法:实验于2005-08/2006-12在河北医科大学西校区实验中心完成。①实验分组:离体豚鼠、小鼠和家兔心肌各分为9组:空白对照组、溶剂对照组、递增累积浓度白藜芦醇组(浓度为10-6,3×10-6,10-5,3×10-5,10-4,3×10-4mol/L),白藜芦醇对照组(5×10-5mol/L),ATP敏感性钾通道阻断剂格列苯脲(5×10-5mol/L)预孵育 白藜芦醇组,钙激活钾通道阻断剂四乙胺(10-3mol/L)预孵育 白藜芦醇组,电压依赖性钾通道阻断剂4-氨基吡啶(10-3mol/L)预孵育 白藜芦醇组,内向整流钾通道阻断剂氯化钡(10-4mol/L)预孵育 白藜芦醇组,乙酰胆碱调节钾通道阻断剂阿托品(10-5mol/L)预孵育 白藜芦醇组。②实验方法:不同类型的钾通道阻断剂均预孵育15min后,分别加入白藜芦醇(终浓度为5×10-5mol/L),连续记录30min,与相应动物白藜芦醇对照组相比较。③评估指标:分析不同阻断剂与白藜芦醇联用对心房收缩力下降率及心率抑制率的影响。结果:①白藜芦醇可降低豚鼠和小鼠离体心肌收缩力和心率(P<0.05),并被ATP敏感性钾通道阻断剂格列苯脲和钙激活钾通道阻断剂四乙胺部分阻断。②白藜芦醇可降低家兔离体心肌心率,格列苯脲可阻断白藜芦醇的负性变时作用。③电压依赖性钾通道阻断剂4-氨基吡啶、内向整流钾通道阻断剂氯化钡、乙酰胆碱调节钾通道阻断剂阿托品均不能阻断白藜芦醇对3种不同动物离体心房收缩力和心率的作用(P>0.05)。结论:白藜芦醇可呈剂量依赖性减慢豚鼠、小鼠和家兔的心率,白藜芦醇可减弱豚鼠心肌收缩力,其作用是与开放ATP敏感性钾通道有关,而与电压依赖性钾通道、内向整流钾通道和乙酰胆碱调节钾通道无关。同时,钙激活钾通道也参与了白藜芦醇对豚鼠和小鼠离体心房收缩力和/或心率的抑制作用。白藜芦醇对离体心肌收缩力和心率的作用有种属差异性。  相似文献   
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