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21.
Kim C. Donaghue M.M. Pena A.T.W. Fung M. Bonney N.J. Howard M. Silink J. Schwingshandl 《Diabetic medicine》1995,12(10):868-873
The study aimed to compare the longitudinal assessment of autonomic nerve function by computerized infrared pupillometry and standard cardiovascular tests in adolescents with diabetes. Adolescents (n = 150) were assessed at two time points (T1 and T2). The median time interval between assessments was 1.5 (range 0.9–3) years. At T1 the median age was 14.5 (range 8.3–19.5) years and the median duration was 6.5 (range 1.1–16) years. The pupillary variables assessed included the resting pupil diameter, the maximum constriction velocity, and the reflex amplitude of constriction. Heart rate reflexes were assessed in response to deep breathing, the Valsalva manoeuvre, and on standing from a lying position (30/15 ratio). Between visits there was a significant decrease in maximum constriction velocity (6.0 mm s?1 vs 6.3 mm s?1, p = 0.0001) and resting pupil diameter (6.2 mm vs 6.3 mm, p = 0.001). At reassessment pupillary abnormalities increased from 32 (21 %) to 45 (30%), with 17 (54 %) of the initial abnormalities persisting. Adolescents with abnormally slow maximum constriction velocity compared to those with normal maximum constriction velocity had a higher glycated haemoglobin (HbA1c%) at T2 (p = 0.02) and between assessments (p = 0.01). Cardiovascular test abnormalities did not increase between visits and the persistence of initial abnormalities was low (21 %). In summary, pupillometry appears a more sensitive test of autonomic nerve dysfunction in adolescents with diabetes than assessment of cardiovascular reflexes. 相似文献
22.
23.
Jan E. Zejda Thomas S. Hurst Ernest M. Barber Charles Rhodes James A. Dosman 《American journal of industrial medicine》1993,23(5):743-750
A cross-sectional survey on respiratory health in swine producers showed that 30% of 301 examined men usually used a dust mask when working inside a barn. They did not differ significantly from dust mask nonusers in respect to respiratory symptoms and lung function. This analysis was undertaken to determine whether the respiratory health of dust mask users was associated with reasons why they had started individual respiratory protection. The subjects were recontacted in order to identify those who started using a mask to deliberately prevent symptoms (42 men) and those who started protection because of pre-existing respiratory symptoms (44 men). Not unexpectedly, betweengroup comparisons of respiratory symptoms and lung function suggest that swine producers who wear dust masks for preventive purposes have better respiratory health than those who wear dust masks because of symptoms or those who do not use individual respiratory protection. The individual reasons for starting dust mask usage should be examined among potential determinants of the outcomes of prospective studies which can then provide more valid assessment of the effect of individual respiratory protection. © 1993 Wiley-Liss, Inc. 相似文献
24.
Dennis J. Murphy 《Drug development research》1994,32(4):237-246
The known effects of drugs from a variety of pharmacologic/therapeutic classes on the respiratory system and worldwide regulatory requirements support the need for conducting respiratory evaluations in safety pharmacology. The objective of these studies is to evaluate the potential for drugs to cause secondary pharmacologic or toxicologic effects that influence respiratory function. Changes in respiratory function can result either from alterations in the pumping apparatus that controls the pattern of pulmonary ventilation or from changes in the mechanical properties of the lung that determine the transpulmonary pressures (work) required for lung inflation and deflation. Defects in the pumping apparatus are classified as hypo- or hyperventilation syndromes and are evaluated by examining ventilatory parameters in a conscious animal model. The ventilatory parameters include respiratory rate, tidal volume, minute volume, peak (or mean) inspiratory flow, peak (or mean) expiratory flow, and fractional inspiratory time. Defects in mechanical properties of the lung are classified as obstructive or restrictive disorders and can be evaluated in animal models by performing flow-volume and pressure-volume maneuvers, respectively. The parameters used to detect airway obstruction include peak expiratory flow, forced expiratory flow at 25 and 75% of forced vital capacity, and a timed forced expiratory volume, while the parameters used to detect lung restriction include total lung capacity, inspiratory capacity, functional residual capacity, and compliance. Measurement of dynamic lung resistance and compliance, obtained continuously during tidal breathing, is an alternative method for evaluating obstructive and restrictive disorders, respectively, and is used when the response to drug treatment is expected to be immediate (within minutes post-dose). The species used in the safety pharmacology studies conducted in our laboratory are the same as those used in toxicology studies since pharmacokinetic and toxicologic/pathologic data are available in these species. These data can be used to help select test measurement intervals and doses and to aid in the interpretation of functional change. The techniques and procedures for measuring respiratory function parameters are well established in guinea pigs, rats, and dogs. 相似文献
25.
本研究采用先进的三维超声成像技术及多普勒技术对正常育龄妇女月经周期中心血管功能进行研究。结果:月经周期中HR、BP无变化;血清E2是周期性变化,排卵前达高峰。SV、CO、EF在排卵前期升高达峰值,显著高于月经期和黄体期;SVR排卵前期最低,而Ved、Ves无变化。Vmax、A、E在内源性E2高峰时明显加快,而E/A比值无明显变化。结果提示:月经周期中随内源性E2的周期性变化,心脏功能也发生周期性变化。E2高峰时,心输出量、心搏量和射血分数达最高。外周阻力最低,心脏内血流速度加快。 相似文献
26.
Institute of Biochemistry, Academy of Sciences of the Uzbek SSR, Tashkent. (Presented by Academician of the Academy of Medical Sciences of the USSR Yu. A. Pankov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 113, No. 2, pp. 168–170, February, 1992. 相似文献
27.
Mnica De la Fuente Juan Jos Garrido Rosa María Arahuetes Angel Hernanz 《Journal of neuroimmunology》1993,42(1)
The neuropeptides neurotensin and neuromedin N (from 10−12 M to 10−9 M) have been showed in this study to stimulate significantly in vitro several steps of the phagocytic process: adherence to substrate, chemotaxis, ingestion of inert particles (latex beads) and production of superoxide anion measured by nitroblue tetrazolium reduction in resting peritoneal macrophages from BALB/c mice. A dose-response relationship was observed, with a maximal stimulation of the phagocytic process at 10−11 M. The two neuropeptides induced no change of intracellular cyclic AMP in murine macrophages. Moreover, adherence and chemotaxis decreased significantly in the presence of EGTA (1 mM), a chelator of extracellular Ca2+, or ryanodine (0.5 mM), a blocker of a Ca2+-gated channel from the endoplasmic reticulum, in both controls and samples with the addition of neurotensin or neuromedin N. These results suggest that there is no relation between the cAMP messenger system and the phagocytic process stimulation in murine peritoneal macrophages by neurotensin or neuromedin N. In addition, the results observed with EGTA and ryanodine could indicate that these two neuropeptides produce their effects through an increase of intracellular Ca2+ concentration. 相似文献
28.
BACKGROUND: Patient education is integral part of any diabetes therapy in Germany, but elderly patients are not able to follow the variety of topics comprising standard treatment and teaching programmes (TTP), primarily due to impaired neuropsychological function. This leads to deficits in diabetes knowledge and hindered ability for diabetes self-management. AIM: To evaluate structured TTP for geriatric patients with impaired cognitive function. PATIENTS AND METHODS: A neuropsychological examination was performed on all patients over 54 years [n=102, age 68.6 +/- 8.7 years, diabetes duration 10.3 (0.03-35.4) years, HbA1c 10.3 +/- 1.7% (HPLC, Diamat, NR 4.5-6.3%), cognitive function 87.7 +/- 12.3 IQ points] who took part in TTP for insulin therapy. Patients with impaired cognitive function participated either in the standard TTP of Berger [n = 35, age 67.6 +/- 8.9 years, diabetes duration 9.9 (0.04-35.4) years, HbA1c 10.3 +/- 2.0%] or in the specialized structured geriatric DICOF-TTP [n=33, age 70.4 +/- 8.2 years, diabetes duration 10.4 (0.03-24.9) years, HbA1c 10.7 +/- 1.8%]. RESULTS: After TTP there were no differences in knowledge and ability for diabetes self-management (standard/DICOF: knowledge 11.0 +/- 2.6 vs. 12.2 +/- 2.7 points, P = 0.11; handling 14.9 +/- 3.3 vs. 15.9 +/- 2.5 points, P = 0.18). However, patients who took part in the DICOF programme showed better scores in satisfaction with the education programme [standard/DICOF 44.7 (31-57) vs. 52.5 (45-59) points, P < 0.001]. Six months later the DICOF participants showed better results regarding diabetes self-management (standard/DICOF: handling 12.5 +/- 4.1 vs. 15.9 +/- 3.1 points, P = 0.001). Both groups showed HbA1c decrease (8.3 +/- 1.4 vs. 8.5 +/- 1.3%, P=0.62) and similar incidence of acute complications. CONCLUSIONS: Elderly patients with impaired cognitive function should take part in specialized structured TTP. This leads to both better satisfaction with the education programme and an improved ability for diabetes self-management. 相似文献
29.
目的 探讨精浆中白细胞介素 1β(IL 1β)、白细胞介素 2 (IL 2 )、白细胞介素 4 (IL 4 )、白细胞介素 6 (IL 6 )、白细胞介素 8(IL 8)、白细胞介素 10 (IL 10 )、肿瘤坏死因子 α(TNF α)等细胞因子浓度与不育症患者之间以及精子的各项功能指标之间的相互关系。方法 应用放射免疫分析(RIA)技术对 12 6例不育男性精浆中IL 1β、IL 2、IL 4、IL 6、IL 8、IL 10、TNF α水平进行了检测。结果 不育症组精浆IL 1β、IL 2、IL 6、IL 8、TNF α含量均高于生育组 ,两组间均存在显著性差异(P <0 .0 5或P <0 .0 1) ;精浆IL 4、IL 10含量均低于生育组 ,两组间均存在显著性差异 (P <0 .0 1)。不育症组精浆中IL 1β、IL 2、IL 4、IL 6、IL 8、IL 10、TNF α含量在WBC精液组与非WBC精液组、血清AsAb阳性组与血清AsAb阴性组之间均存在显著性差异 (P <0 .0 5或P <0 .0 1) ;精浆中IL 4、TNF α含量在精子活动力、活动率、精子穿透力、顶体完整率、尾部肿胀率正常组与不正常组之间均存在显著性差异 (P <0 .0 5或P <0 .0 1)。 结论 精浆中IL 1β、IL 2、IL 4、IL 6、IL 8、IL 10、TNF α含量与男性不育症患者之间存在密切关系 ,检测精浆中IL 1β、IL 2、IL 4、IL 6、IL 8、IL 10、TNF α的含量可以反映男性 相似文献
30.
Genetic contributions to Parkinson's disease 总被引:8,自引:0,他引:8
Sporadic Parkinson's disease (PD) is a common neurodegenerative disorder, characterized by the loss of midbrain dopamine neurons and Lewy body inclusions. It is thought to result from a complex interaction between multiple predisposing genes and environmental influences, although these interactions are still poorly understood. Several causative genes have been identified in different families. Mutations in two genes [α-synuclein and nuclear receptor-related 1 (Nurr1)] cause the same pathology, and a third locus on chromosome 2 also causes this pathology. Other familial PD mutations have identified genes involved in the ubiquitin–proteasome system [parkin and ubiquitin C-terminal hydroxylase L1 (UCHL1)], although such cases do not produce Lewy bodies. These studies highlight critical cellular proteins and mechanisms for dopamine neuron survival as disrupted in Parkinson's disease. Understanding the genetic variations impacting on dopamine neurons may illuminate other molecular mechanisms involved. Additional candidate genes involved in dopamine cell survival, dopamine synthesis, metabolism and function, energy supply, oxidative stress, and cellular detoxification have been indicated by transgenic animal models and/or screened in human populations with differing results. Genetic variation in genes known to produce different patterns and types of neurodegeneration that may impact on the function of dopamine neurons are also reviewed. These studies suggest that environment and genetic background are likely to have a significant influence on susceptibility to Parkinson's disease. The identification of multiple genes predisposing to Parkinson's disease will assist in determining the cellular pathway/s leading to the neurodegeneration observed in this disease. 相似文献