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51.
STUDY OBJECTIVE: To compare the health status and factors influencing the health of populations that had previously lived under different political systems. DESIGN: Cross sectional health and social survey using postal interviews. The relation between self reported health and psychosocial factors (stressful life events, social support, education, health promoting life style and health endangering behaviour) was investigated. To determine East-West differences a logistic regression model including interaction terms was fitted. SETTING: East and West Berlin shortly after reunification 1991. PARTICIPANTS: Representative sample of 4430 Berlin residents aged 18 years and over (response rate 63%). RESULTS: Of all respondents, 15.4% rated their health as unsatisfactory. Residents of East Berlin rated their health more frequently as unsatisfactory than residents of West Berlin (Or(age adjusted)= 1.29, 95%CI 1.08, 1.52), these differences occurred predominantly in the over 60 years age group. Logistic regression showed significant independent effects of stressful life events, social support, education, and health promoting life style on self rated health. The effects of education and health promoting life style were observed to be more pronounced in the western part of Berlin. Old age and female sex showed a stronger association with unsatisfactory health status in the eastern part of Berlin. CONCLUSIONS: For subjects aged over 60 years there was evidence that living in the former East Berlin had an adverse effect on health compared with West Berlin. The impact of education and a health promoting lifestyle on self rated health seemed to be weaker in a former socialist society compared with that of a Western democracy. This study supports an "additive model" rather than a "buffering model" in explaining the effects of psychosocial factors on health.  相似文献   
52.
Longitudinal zinc (Zn) balance studies were performed under domestic conditions in term breast-fed (n = 10), term formula-fed (n = 5; Zn concentration in the formula: 4 mg/l) and preterm formula-fed (n = 3) infants during the first 17 weeks of life. Samples of milk, urine and feces were analyzed by atomic absorption spectrometry. The median daily Zn intake in breast-fed infants decreased from 0.592 (0.457-0.829) mg Zn/kg body weight to 0.151 (0.095-0.304) mg Zn/kg body weight in the first 17 weeks of life; comparable values for bottle-fed term infants were 0.58 (0.511-0.701) and 0.674 (0.529-0.731) mg Zn/kg body weight. The median percent retention of Zn intake was 27 (-60 to 81.4)% in breast-fed infants and 21.5 (-42 to 64)% in formula-fed infants. In view of the urinary and fecal Zn losses measured, a daily intake of 0.3-0.5 mg Zn/kg body weight is considered to be sufficient to ensure a Zn retention equivalent to breast-fed infants. This requires a Zn concentration of 2-3 mg/l of Zn depending on milk volume intake.  相似文献   
53.
Iron balances in infant nutrition   总被引:1,自引:0,他引:1  
Iron balance studies were performed in 17 full term male infants from their 3rd until their 17th week of life. The balance studies were made in the infant's home and comprised 5 periods with an interval of 3-4 weeks, each consisting of three 24-hour collections. Ten infants were breast-fed, 3 received an adapted infant formula (P1, iron content 1.1 mg/l) and 4 were given the same formula enriched with iron, copper and zinc (P2, iron content 10.35 mg/l). From the 3rd to the 17th week of life the breast-fed infants got a mean iron intake of 0.2 mg/kg body weight X 3 days and they retained 0.09 mg/kg b.w. X 3 days. The P1 group received 0.48 and 0.47 mg/kg b.w. X 3 days and retained -0.01 and -0.5 mg iron/kg b.w. X 3 days, while the P2 group had an intake from 5.04 to 6.38 mg b.w. X 3 days and retained between 1.13 and 3.66 mg iron/kg b.w. X 3 days. Comparing the 3 groups it can be concluded that the P1 group retained definitely less iron than the breast-fed group, whereas the P2 group retained 12 to 40 times more iron than the breast-fed babies.  相似文献   
54.
Illness management is a broad set of strategies designed to help individuals with serious mental illness collaborate with professionals, reduce their susceptibility to the illness, and cope effectively with their symptoms. Recovery occurs when people with mental illness discover, or rediscover, their strengths and abilities for pursuing personal goals and develop a sense of identity that allows them to grow beyond their mental illness. The authors discuss the concept of recovery from psychiatric disorders and then review research on professional-based programs for helping people manage their mental illness. Research on illness management for persons with severe mental illness, including 40 randomized controlled studies, indicates that psychoeducation improves people's knowledge of mental illness; that behavioral tailoring helps people take medication as prescribed; that relapse prevention programs reduce symptom relapses and rehospitalizations; and that coping skills training using cognitive-behavioral techniques reduces the severity and distress of persistent symptoms. The authors discuss the implementation and dissemination of illness management programs from the perspectives of mental health administrators, program directors, people with a psychiatric illness, and family members.  相似文献   
55.
OBJECTIVE: Nerve growth factor is important for the development and function of the cholinergic basal forebrain. The authors examined the hypothesis that the concentration of nerve growth factor is lower than normal in the preclinical phase of neurodegenerative dementia, especially Alzheimer's disease. METHOD: The serum nerve growth factor concentration of subjects from the Berlin Aging Study and the Berlin Memory Clinic who later developed Alzheimer's disease were compared with those of subjects who were free of dementia and subjects who were already suffering from Alzheimer's disease. RESULTS: There were 17 subjects in each group, matched for age and sex. The three groups differed in log-10-transformed mean nerve growth factor concentrations: 1.62 (SD=0.59) for the healthy comparison subjects, 0.92 (SD=0.30) for the subjects with preclinical dementia, and 1.44 (SD=0.61) for the subjects with Alzheimer's disease. CONCLUSIONS: These results support the hypothesis of disturbed nerve growth factor regulation in the serum of patients with preclinical Alzheimer's disease. Mechanisms by which these disturbances appear are unclear, but they may reflect the situation in the preclinical Alzheimer's disease brain.  相似文献   
56.
This review focuses on the mechanisms and sites of action underlyingß-adrenergic antagonism in perioperative medicine.A large body of knowledge has recently emerged from basic andclinical research concerning the mechanisms of the life-savingeffects of ß-adrenergic antagonists (ß-AAs)in high-risk cardiac patients. This article re-emphasizes themechanisms underlying ß-adrenergic antagonism andalso illuminates novel rationales behind the use of perioperativeß-AAs from a biological point of view. Particularly,it delineates new concepts of ß-adrenergic signaltransduction emerging from transgenic animal models. The roleof the different characteristics of various ß-AAsis discussed, and evidence will be presented for the selectionof one specific agent over another on the basis of individualdrug profiles in defined clinical situations. The salutary effectsof ß-AAs on the cardiovascular system will be describedat the cellular and molecular levels. ß-AAs exhibitmany effects beyond a reduction in heart rate, which are lessknown by perioperative physicians but equally desirable in theperioperative care of high-risk cardiac patients. These includeeffects on core components of an anaesthetic regimen, such asanalgesia, hypnosis, and memory function. Despite overwhelmingevidence of benefit, ß-AAs are currently under-utilizedin the perioperative period because of concerns of potentialadverse effects and toxicity. The effects of acute administrationof ß-AAs on cardiac function in the compromised patientand strategies to counteract potential adverse effects willbe discussed in detail. This may help to overcome barriers tothe initiation of perioperative treatment with ß-AAsin a larger number of high-risk cardiac patients undergoingsurgery. Br J Anaesth 2002; 88: 101–23  相似文献   
57.
Background: The usefulness of peripheral nerve blockade in the anesthetic management of hip surgery has not been clearly established. Because sensory afferents from the hip include several branches of the lumbar plexus, the authors hypothesized that a lumbar plexus block could reduce pain from a major hip procedure.

Methods: In a double-blind prospective trial, 60 patients undergoing total hip arthroplasty were randomized to receive general anesthesia with (plexus group, n = 30) or without (control group, n = 30) a posterior lumbar plexus block. The block was performed after induction using a nerve stimulator, and 0.4 ml/kg bupivacaine, 0.5%, with epinephrine was injected. General anesthesia was standardized, and supplemental fentanyl was administered per hemodynamic guidelines. Postoperative pain and patient-controlled intravenous morphine use were serially assessed for 48 h.

Results: The proportion of patients receiving supplemental fentanyl intraoperatively was more than 3 times greater in the control group (20 of 30 vs. 6 of 29, P = 0.001). In the postanesthesia care unit, a greater than fourfold reduction in pain scores was observed in the plexus group (visual analogue scale [VAS] pain score at arrival 1.3 +/- 2 vs. 5.6 +/- 3, P < 0.001), and "rescue" morphine boluses (administered if VAS > 3) were administered 10 times less frequently (in 2 of 28 vs. in 22 of 29 patients, P < 0.0001). Pain scores and morphine consumption remained significantly lower in the plexus group until 6 h after randomization (VAS at 6 h, 1.4 +/- 1.3 vs. 2.4 +/- 1.4, P = 0.007; cumulative morphine at 6 h, 5.6 +/- 4.7 vs. 12.6 +/- 7.5 mg, P < 0.0001). Operative and postoperative (48 h) blood loss was modestly decreased in the treated group. Epidural-like distribution of anesthesia occurred in 3 of 28 plexus group patients, but no other side-effects were noted.  相似文献   

58.
The degree of platelet adhesion and subsequent thrombus formation is an important measure of biocompatibility for cardiovascular biomaterials. Traditional methods of quantifying platelet adhesion often are limited by the need for direct optical access, limited spatial resolution, or the lack of temporal resolution. We have developed a new imaging system that utilizes fiber optics and fluorescence microscopy for the quantification of platelet adhesion. This fiber optic remote microscope is capable of imaging individual fluorescently labeled platelets in whole blood on opaque surfaces. Using this method, platelet adhesion was quantified on a series of metallic [low-temperature isotropic carbon (LTIC); titanium alloy (Ti); diamond-like carbon (DLC); oxidized titanium alloy (TiO); and polycrystalline diamond (PCD)] and polymeric [woven Dacron (WD)] collagen-impregnated Dacron (HEM), expanded polytetrafluoroethylene (ePTFE), and denucleated ePTFE (dePTFE)] biomaterials designed for use in cardiovascular applications. These materials were perfused with heparinized whole human blood in an in vitro parallel plate flow chamber. Platelet adhesion after 5 min of perfusion ranged from 3.7 +/- 1.0 (dePTFE) to 16.8 +/- 1.5 (WD) platelets/1000 micrometer. The temporal information revealed by these studies provides a comparative measure of the acute thrombogenicity of these materials as well as some insight into their long-term hemocompatibilities. Also studied here were the effects of wall shear rate and axial position on platelet adhesion. A predicted increase in platelet adhesion with increased wall shear rate and a trend toward a decrease in platelet adhesion with increased axial distance was observed with the fiber optic microscope. Future applications for this imaging technique may include the long-term evaluation of thrombosis in blood-contacting devices in vitro and, in animal models, in vivo.  相似文献   
59.
BACKGROUND: Molybdenum concentrations in formulas exceed those in human milk by far. Infants with phenylketonuria require semisynthetic phenylalanine-restricted diets. Because these diets are presently supplemented with molybdenum, a study was conducted to determine whether retention and plasma concentration in the recipients are equivalent to those of healthy breast-fed infants. METHODS: Balance and plasma studies were conducted in healthy breast-fed infants (n = 17) and in patients with phenylketonuria (n = 4) at the age of 4 weeks, and the plasma investigations were repeated at the ages of 4 and 12 months. The samples were analyzed by atomic absorption spectroscopy (balance studies) and high-resolution inductively coupled plasma mass spectrometry (plasma). RESULTS: Molybdenum intake and retention in all infants with phenylketonuria were more than 18 times those of breast-fed infants. The plasma concentrations reflected these differences. A median of 0.04 microg/l was assessed in breast-fed infants at 4 weeks and less than 0.02 microg/l at 4 months of age. Comparative results of infants with phenylketonuria were 2.9 microg/l and 2.5 microg/l, respectively. There were no significant differences between the groups at 12 months of age. CONCLUSIONS: The phenylketonuria diets investigated showed excessive retention and plasma concentrations of the essential trace element molybdenum in early infancy. In view of these findings, the present practice of molybdenum fortification should be revised.  相似文献   
60.
Human growth hormone (HGH) radio-immunoassay (RIA) was adapted for an accurate measurement of immunoreactive HGH concentrations in the CSF in different cases of hypothalamic-somatotropin dysfunctions.In control subjects (n = 43) mean HGH levels were 0.35 ± 0.03 ng/ml in CSF and 1.95 ± 0.2 ng/ml in plasma with a CSFplasma ratio of 17%. The thyroid-stimulating hormone (TSH) RIA gave in controls mean basal levels of 2.65 ± 0.2 μU/ml in CSF and 5.95 ± 0.3 μU/ml in plasma with a CSFplasma ratio of 44%. HGH and TSH concentrations in CSF and plasma show a very good correlation; but the regression curves for both hormones are distinctly different and appear specific for each polypeptide hormone.Hypothalamic-somatotropin hyperreactivity was reported in diabetic retinopathy (DR). CSF and plasma HGH concentrations in a group of diabetic patients with progressing retinopathy (n = 27) were not different from those in normal subjects (respectively 0.35 ± 0.05 in CSF and 2.10 ± 0.25 ng/ml in plasma with a CSFplasma ratio of 16%). The HGH regression curve obtained in diabetics is similar to that of controls. These data do not substantiate the hypothesis of an HGH hyperreactivity in diabetic retinopathy.In somatotropin hypersecretion (acromegaly) without adenoma suprasellar extension, higher HGH concentrations recorded in CSF than in plasma cannot be attributed to an anatomical break-down of the CSF blood-brain barrier and suggest an active transport process of pituitary hormones to the CNS.HGH and TSH concentrations were measured in the cystic fluid of CNS tumors. In 1 case of a cystic dysembryoma, the HGH and TSH of CF were considerably increased. In gliomas (n = 8) the HGH and TSH cystic fluid concentrations were more elevated (respectively 0.72 ± 0.2 ng/ml and 3.6 ± 0.7 μU/ml) than in the CSF of controls.  相似文献   
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