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51.
Objectives: When perinatal medicine emerged as a new medical discipline in the 1960s, Berlin was as one of the world's leading centers. During that time, the city was separated into two parts, each fostering its own health care system. After the destruction of the Berlin Wall, it was possible to speak with the citizens of East Berlin and to access their database systems. This created the singular opportunity to objectively compare the development of perinatal care in both parts of Berlin. Methods: Rates of maternal, perinatal, and infant mortality as well as the rate of preterm deliveries were evaluated over time and between East and West Berlin. The timing of introduction of 20 specific perinatal interventions was evaluated across 18 hospitals with more than 500 deliveries (11 in West Berlin and 7 in East Berlin). Interviews were conducted with 100 gynecologists, 100 midwives, and 100 women who had recently delivered their first child from each side of the city regarding their opinions of the importance of these interventions for the quality of perinatal medicine and how they would distribute a budget to improve maternity care. Results: Maternal, perinatal, and infant mortality decreased in both parts of Berlin until 1990 (p<0.0001), without significant differences between East and West Berlin, though the preterm delivery rate was slightly lower in East Berlin compared with West Berlin (p<0.06). Some new clinical techniques and treatments—such as cardiotocography, ultrasound, tocolytic therapy, and peridural anesthesia—were introduced earlier in West Berlin. In contrast, certain public health measures—such as maternal transport, screening programs for diabetes, and support of breastfeeding—were introduced much earlier in East Berlin. There were significant differences between the beliefs of gynecologists, midwives, and mothers in East and West Berlin. In general, citizens of East Berlin were more enthusiastic about technological medical advances, whereas citizens of West Berlin were more supportive of public health and alternative methods. In addition, there were significant differences between female and male physicians in their beliefs about how to improve health care, regardless of whether they resided in East or West Berlin. Conclusions: The results of this study may serve as a basis for reflection on how different social circumstances and health care policies can influence the improvement of maternal and child health care.  相似文献   
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BACKGROUND: The risk of breast cancer was investigated in a large dynamic population-based cohort of all 1.1 million economically active women in Norway with potential exposure to 50 Hz magnetic fields at the censuses of 1960, 1970, and 1980. METHODS: The follow-up period for the cohort was 1961-1992. For each woman, date of birth and census information on occupation and socioeconomic status were ascertained. These data were linked to the breast cancer morbidity information in the Cancer Registry of Norway. Exposure to magnetic fields was assessed a priori using two different approaches. In the first approach, hours per week in a potential magnetic field above background level (0.1 microT) were classified by an expert panel. In the second approach, measured magnetic fields from a separate study of men at work were allocated to the women's census job titles. In both approaches, exposure was cumulated over the years of employment (work hours and microT-years, respectively). RESULTS: The Poisson regression analysis showed a risk ratio (RR) of 1.14 (95% confidence interval (CI) = 1.10-1.19) in the highest exposure category compared to the lowest when using the first approach, and the corresponding RR was 1.08 (95% CI = 1.01-1.16) when using the second approach. For women younger than 50 years, RR was 1.20 (95% CI = 1.11-1.29) and 1.12 (95% CI = 0.98-1.28), respectively. CONCLUSIONS: The results give some support to the hypothesis that exposure to 50 Hz magnetic fields may increase the risk of breast cancer. However, since no direct information on exposure was available, no firm conclusions can be drawn.  相似文献   
54.
BACKGROUND: Although cataract surgery is highly developed today, there are still problems such as secondary cataract. In polishing the posterior capsule lens, epithelial cells often remain, causing secondary cataracts. Additionally, there are the problems of tissue heating and endothelial cell loss during phacoemulsification by ultrasound. This could be another field for improvement of cataract surgery by using the waterjet. METHODS: After removing the cornea of freshly enucleated porcine bulbs, we used the water jet from 4 to 12 bar. The hit angel on the capsule varied between 45 degrees and 90 degrees. RESULTS: Rupture of the posterior capsule occurred at a mean of 8.5 bar using the jet at 45 degrees and a mean of 8.6 bar using the jet at 90 degrees. CONCLUSION: The waterjet pressure should not be over 4 bar during polishing of the posterior capsule.  相似文献   
55.
1. The arachidonic acid derivative arachidonylethanolamide (anandamide) is an endogeneous ligand of cannabinoid receptors that induces pharmacological actions similar to those of cannabinoids such as delta9-tetrahydrocannabinol (THC). We examined whether anandamide can influence excessive neuronal activity by investigating stimulation-induced population spikes and epileptiform activity in rat hippocampal slices. For this purpose, the effects of anandamide were compared with those of the synthetic cannabinoid agonist WIN 55,212-2 and its inactive S(-)-enantiomer WIN 55,212-3. 2. Both anandamide (1 and 10 microM) and WIN 55,212-2 (0.1 and 1 microM) decreased the amplitude of the postsynaptic population spike and the slope of the field excitatory postsynaptic potential (field e.p.s.p.) without affecting the presynaptic fibre spike of the afferents. At a concentration of 1 microM, WIN 55,212-2 completely suppressed the postsynaptic spike, whereas the S(-)-enantiomer WIN 55,212-3 produced only a slight depression. The CB1 receptor antagonist SR 141716 blocked the inhibition evoked by the cannabinoids. SR 141716 had a slight facilitatory effect on neuronal excitability by itself. 3. Anandamide shifted the input-output curve of the postsynaptic spike and the field e.p.s.p. to the right and increased the magnitude of paired-pulse facilitation indicating a presynaptic mechanism of action. 4. Anandamide and WIN 55,212-2, but not WIN 55,212-3, attenuated both stimulus-triggered epileptiform activity in CA1 elicited by omission of Mg2+ and spontaneously occurring epileptiform activity in CA3 elicited by omission of Mg2+ and elevation of K+ to 8 mM. The antiepileptiform effect of these cannabinoids was blocked by SR 141716. 5. In conclusion, cannabinoid receptors of the CB1 type as well as their endogeneous ligand, anandamide, are involved in the control of neuronal excitability, thus reducing excitatory neurotransmission at a presynaptic site, a mechanism which might be involved in the prevention of excessive excitability leading to epileptiform activity.  相似文献   
56.
The aim of this study was to characterize the properties of endothelin (ET)-receptor subtypes mediating inositol phosphate (IP)-formation in rat kidney and their regulation during ontogenesis. In renal cortical slices of adult rats (12–16 weeks old) ET's concentration-dependently increased IP-formation with an order of potency ET -1 ET 3. While the non-selective ET receptor antagonist bosentan (10 M) completely suppressed ET-induced IP-formation, the ETA-receptor antagonist BQ-123 (10 M) inhibited it only by 70%, the ETB-receptor antagonist IRL 1038 (1 M) by 25%; combined application of BQ-123 + IRL 1038 caused complete inhibition of ET-1-induced IP-formation. Pretreatment of isolated renal cells with pertussis toxin (PTX, 500 ng/ml) overnight did not attenuate but significantly increased ET-1-induced IP-formation. Ontogenetic studies in renal slices from neonatal, 1, 2, 3, 6, 12 and 24 weeks old rats revealed that ET-1-induced IP-formation maturation-dependently declined being highest in neonatal rats (increase: 169% over basal) and lowest in 24 weeks old rats (increase: 47% over basal). This decline in ET-induced IP-formation was accompanied by a decrease in renal ET receptor number and the amount of immunodetectable Gq/11 (assessed by Western-blotting using the QL-antiserum). Moreover, ET receptor subtypes changed during the maturation process: from neonates to 12 weeks old rats number and functional responsiveness of ETA-receptors declined, while that of ETB-receptors increased. We conclude that in adult rat renal cortex ET-induced IP-formation is mediated by activation of both ETA- and ETB-receptors and does not involve a PTX-sensitive G-protein. ET-induced IP-formation declines during the maturation process; this is associated with a decrease in ET-receptor number and the immunodetectable amount of Gq/11.  相似文献   
57.
Zusammenfassung Der standardisierte Fragebogen zur Erfassung muskuloskeletaler Beschwerden des japanischen Komitees zum Studium arbeitsbedingter Gesundheitsstörungen im Hals-Arm-Gebiet wurde auf Deutsch übertragen und seine Reliabilität und Validität überprüft. Im Fragebogen wird anhand eines Körperschemas nach der Häufigkeit (nie/selten, gelegentlich, fast täglich) von Beschwerden (Schmerzen, Steifigkeit, Müdigkeit) in 12 Körperregionen gefragt. Der Fragebogen wurde gleichzeitig mit ärztlichen Palpationsuntersuchungen bei 644 Personen aus zwölf Berufsgruppen im Dienstleistungssektor eingesetzt. Auf Grund einer Faktoranalyse der Fragebogenresultate kann festgestellt werden, dass Beschwerden regional getrennt (nämlich im Nacken-Schultergebiet, dem Rücken und je der rechten und linken oberen Extremität) auftreten und für diese Regionen die Symptome zu Indizes zusammengefasst werden können. Diese Indizes sind reliabel (Cronbach 0.8). Mit zunehmenden Indexwerten nehmen schmerzhafte Palpationsbefunde stetig zu. Beschwerden korrelieren mit vermehrtem Medikamentenkonsum und Arztkonsultationen. Der Fragebogen stellt folglich ein valides Untersuchungsinstrument für muskuloskeletale Beschwerden am Arbeitsplatz dar.
Summary The standardized illustrated questionnaire on musculoskeletal disorders of the Japanese Committee on Occupational Cervico-brachial Disorders was translated into German. This questionnaire, composed of 37 items about the occurrence (never/seldom, occasionally, almost daily) of symptoms (pain, stiffness, fatique) in twelve body regions, was used together with medical examinations (pressure points), and further information was gathered on the consumption of analgetics and medical visits prompted by musculoskeletal symptoms. The questionnaire's reliability and validity were tested in 644 persons from twelve occupational groups within the service sector. Factoranalyses showed that symptoms can be grouped into four distinct regions of occurrence: neck/shoulder/area, back/low back, and both left and right upper extremities. Indices based on these regions are consistent (Cronbach 0.8). Palpation findings steadily increase with increasing index values. The consumption of medicaments and medical visits positively correlate with the indices. Consequently the questionnaire is judged to be a valid instrument for studying musculoskeletal disorders at the workplace.

Résumé Le questionnaire illustré et standardisé sur les symptômes musculaires et osseux du comité japonais sur la cervico-brachialgie professionelle a été traduit en allemand et sa reliabilité et validité ont été testées. Le questionnaire est composé de 37 variables sur la fréquence (jamais/rarement, par occasion, presque toujours) des symptômes (douleur, raideur, fatigue) dans douze régions du corps. Il était distribué simultanément aux examens médicaux parmi 644 personnes de douze groupes d'employés dans le secteur de service. D'autres informations concernent la fréquence de la consommation des analgésiques et des visites médicales pour des douleurs musculaires. Une analyse factorielle a montré que les symptômes peuvent être groupés en quatre régions du corps: nuque/épaules, dos et les extrémités supérieurs. Les indices sur ces régions sont consistant (Cronbach 0.8). Les douleurs provoquées par la palpation augmentent avec la valeur de l'index. La consommation des analgésiques et les consultations sont correlées avec les indices. Par conséquent, le questionnaire illustré est un instrument valable pour étudier les problèmes musculaires sur les lieux de travail.
  相似文献   
58.
The toxicokinetics of aluminum (Al) in male Wistar rats was studied after single intragastric (IG) doses of 1000 and 12000 g Al/kg and intravenous (IV) doses of 10, 100, 1000, and 12000 g Al/kg. Serial blood samples, daily samples of urine and feces as well as brain, liver, kidney, spleen, quadriceps muscle, and femur samples were collected. Al was measured by atomic absorption spectrometry. Al blood profiles after IV doses were adequately described by a two-compartment open model. Al toxicokinetics was dose dependent and appeared to plateau at 12000 g/kg. At IV doses between 10 and 1000 g/kg the terminal half-life of elimination from whole blood (t1/2) increased from 29.9±7.8 to 209.3±32.6 min, and the total body clearance (CL) decreased from 2.45±0.64 to 0.28±0.03 ml min–1 kg–1. Following an IV bolus of 10 and 100 g/kg the administered Al was recovered completely from urine (94.4%±9.9% and 98.5%±3.2%). Twenty-nine days after the IV dose of 1000 g/kg daily renal excretion decreased to baseline values while only 55.1%±8.0% of the dose was excreted. Nineteen days after the single IV dose of 1000 g/kg Al accumulated in liver (28.1±7.7 versus 1.7±0.5 g/g of control rats) and spleen (72.5±21.1 versus <0.4 g/g). After the single 1000 g/kg IG dose no absorption of Al was detectable. The IG dose of 12000 g/kg resulted in a maximum blood Al level of 47.9±12.4 g/l after 50 min. The blood concentration time curve fitted a one-compartment open model with a half-life of absorption of 28.2±3.6 min and a t1/2 of 81.2±20.2 min. Cumulative renal Al excretion was 0.18%±0.10% of the dose and oral bioavailability was 0.02%. Seventeen days after the 12000 g/kg IG dose the Al content in femur samples was increased (2.7±1.3 versus 0.6±0.4 g/g). In no case was fecal elimination of incorporated Al observed.  相似文献   
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OBJECTIVE: To examine the cost impact of referral to a Mood Disorders Unit (MDU), by comparing pre-service and post-service costs, and MDU and control samples. METHOD: We studied tertiary referral MDU patients and a control group of consultants' depressed patients, with the principal comparison intervals being: (i) 12 months prior to and (ii) 6 months following baseline assessment, with costs annualised to allow the impact of assessment and treatment recommendation to be determined. In addition, we assessed any 'personal cost' of depression. RESULTS: Following baseline assessment, MDU referrals showed a reduction in costs, while controls' costs increased, largely driven by contrasting directions in hospitalisation and social welfare costs. We identify variables associated with high and increased costs, including features of the earlier stages of the disorder, whether social welfare was received, diagnostic subtype and personality dysfunction, with multivariate analyses refining the variable sets. Self-report data indicated that patients judged the 'personal cost' of depression to exceed more formal cost parameters, so that to experience depression is itself depressogenic. CONCLUSIONS: This first Australian attempt to cost depression and its management in the clinical setting more provides a methodology for wider application in service evaluation studies rather than delivers an unequivocal answer to whether a specialist Mood Disorders Unit is cost efficient or not.  相似文献   
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