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1.
The expert is a mediator between the relevant governmental institution on the one hand and the x-ray equipment manufacturers on the other. The physician can approach the expert in all matters concerning radiation protection. It is only by mutual cooperation between physician, governmental body, manufacturer and expert that the new x-ray regulations can be implemented and enforced. Of course we cannot influence the natural exposure to radiation that has been going on ever since the creation of the Earth. It is the task of radiation protection to keep artificial radiation exposure of the population as low as possible. Every person is expected to contribute towards achieving this aim.  相似文献   
2.
Vaccination with recombinant outer surface protein A (OspA) from Borrelia burgdorferi provides excellent antibody-mediated protection against challenge with the pathogen in animal models and in humans. However, the bactericidal antibodies are ineffective in the reservoir host, since OspA is expressed by spirochetes only in the vector, but rarely, if at all, in mammals. Using an artificially generated immune serum (anti-10(8) spirochetes) with high protective potential for prophylactic and therapeutic treatment, we have now isolated from an expression library of B. burgdorferi (strain ZS7) three novel genes, zs7.a36, zs7.a66 and zs7.a68. All three genes are located, together with ospA/B, on the linear plasmid lp54, and are expressed in vitro and in ticks. At least temporarily two of them, ZS7.A36 and ZS7.A66, are also expressed during infection. The respective natural antigens are poorly immunogenic ininfected normal mice but elicited antibodies in Lyme disease patients. We show that recombinant preparations of ZS7.A36, ZS7.A66 and ZS7.A68 induce functional antibodies in rabbits capable of protecting immunodeficient mice against subsequent experimental infection. These findings suggest that all three recombinant antigens represent potential candidates for a "second generation" vaccine to prevent and/or cure Lyme disease.  相似文献   
3.
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   
4.
The determination of carbohydrate-deficient transferrin (CDT) in serum has been found useful as a marker of increased alcohol consumption of >60 g/day. It is not clear why the reference range is different for women (0 to 26 units/liter) and men (0 to 20 units/liter). We evaluated serum COT in 286 healthy subjects (209 women, 77 men) using a commercially available radioimmunoassay. Premenopausal women had higher CDT levels than postmenopausal women, whereas no age-related difference of CDT levels was found in men. In postmenopausal women, higher CDT levels were associated with estrogen replacement therapy. In premenopausal women, however, neither the phase of the menstrual cycle nor contraceptive steroid use showed a significant association with the increase in CDT levels. No significant correlations were found between CDT and either serum estradiol or serum iron. In conclusion, both premenopausal state and postmenopausal estrogen replacement therapy seem to increase serum levels of CDT. Therefore, menopausal status and exogenous estrogens should be considered when interpreting CDT values in women.  相似文献   
5.
6.

Objective

The objective was to describe the design, implementation and preliminary results of a collaborative care pilot program using hybrid colocation and centralized care management for patients with depression and chronic medical illness in an urban accountable care organization.

Methods

Patients with chronic illness (diabetes mellitus, coronary artery disease and/or congestive heart failure) and comorbid depressive symptoms (Patient Health Questionnaire [PHQ]9 score ≥ 10) were enrolled. The interventions included collaborative care for depression and chronic conditions; behavioral support, including short-term psychotherapy by licensed clinical social worker on-site or telephonically; off-site nurse care management and psychiatrist consultation through an electronic medical record.

Results

Forty-four percent of patients (n= 61) achieved a depression response. In a diabetes subgroup with depression and glycosylated hemoglobin level HbA1c > 8 (n= 21), 33% had a depression response with a minimum 0.5% HbA1c reduction. Among a subgroup (n= 25) with Framingham risk score > 15% and depression, mean PHQ9 depression scores and mean Framingham scores were reduced by 35% and 34%, respectively.

Conclusions

Early experience of the pilot for multiple chronic illnesses and depression appears feasible and shows initial promise.  相似文献   
7.
Inhibition of the interleukin-2 (IL-2) pathway has potent immunosuppressive activity in humans as is evident from the broad therapeutic utility of cyclosporine, rapamycin, tacrolimus, and monoclonal antibodies blocking the high-affinity subunit of the IL-2 receptor (CD25). Here we describe a humanized antibody, MT204, interfering with IL-2 signaling by a novel mechanism. Although MT204 did not prevent IL-2 from binding to CD25, it potently antagonized downstream signaling events of IL-2 at sub-nanomolar concentrations, such as STAT3 tyrosine phosphorylation, expression of CD124, production of gamma-interferon and cell proliferation. While MT204 and the anti-CD25 mAb daclizumab were equally effective in inhibiting autocrine growth of human CD4(+) T cells, MT204 was far superior in preventing proliferation of NKL lymphoma cells, production of gamma-interferon by natural killer (NK) cells and proliferation of primary NK cells. MT204 has potential as a novel immunosuppressive and anti-proliferative therapy with an apparently broader spectrum of activities than anti-CD25 antibodies.  相似文献   
8.
Major depression is associated with impairments in semantic verbal fluency (VF). However, the neural correlates underlying dysfunctional cognitive processing in depressed subjects during the production of semantic category members still remain unclear. In the current study, an overt and continuous semantic VF paradigm was used to examine these mechanisms in a representative sample of 33 patients diagnosed with a current episode of unipolar depression and 33 statistically matched healthy controls. Subjects articulated words in response to semantic category cues while brain activity was measured with functional magnetic resonance imaging (fMRI). Compared to controls, patients showed poorer task performance. On the neural level, a group by condition interaction analysis, corrected for task performance, revealed a reduced task-related deactivation in patients in the right parahippocampal gyrus, the right fusiform gyrus, and the right supplementary motor area. An additional and an increased task-related activation in patients were observed in the right precentral gyrus and the left cerebellum, respectively. These results indicate that a failure to suppress potentially interfering activity from inferior temporal regions involved in default-mode network functions and visual imagery, accompanied by an enhanced recruitment of areas implicated in speech initiation and higher-order language processes, may underlie dysfunctional cognitive processing during semantic VF in depression. The finding that patients with depression demonstrated both decreased performance and aberrant brain activation during the current semantic VF task demonstrates that this paradigm is a sensitive tool for assessing brain dysfunctions in clinical populations.  相似文献   
9.
BACKGROUND: Our knowledge about the bidirectional interactions between brain and whole organism after trauma is still limited. It was the purpose of this prospective clinical study to determine the influence of severe head trauma (SHT) as well as trauma in different anatomic injury regions on posttraumatic inflammatory mediator levels from patients with multiple injuries. METHODS: Thirty-five healthy controls, 33 patients with an isolated SHT, 47 patients with multiple injuries without SHT, and 45 patients with both SHT and multiple injuries were studied. The posttraumatic plasma levels of soluble tumor necrosis factor receptors p55 and p75, interleukin (IL)-6, IL-10, and polymorphonuclear neutrophil (PMN) elastase were monitored using enzyme-linked immunosorbent assay technique. The influence of head injuries as well as thorax, abdomen, and extremity injuries on the mediator release from patients with multiple injuries was investigated by multivariate linear regression models. RESULTS: The soluble tumor necrosis factor receptor p55/p75 ratio was significantly elevated within 3 hours of trauma in all three injury groups and returned to reference ratios after 12 hours. The lowest increase was found in patients suffering from an isolated SHT. Lowest mediator levels in this patient population were also found for IL-6, IL-10, and PMN elastase during the first 36 hours after trauma. Additional injuries to the head, thorax, abdomen, and extremity modulated mediator levels to a different degree. No specific effect was found for SHT when compared with other injury groups. Thorax injuries caused the quickest rise in mediator levels, whereas abdominal injuries significantly increased PMN elastase levels 12 to 24 hours after trauma. CONCLUSION: Traumatic injuries cause the liberation of various mediators, without any specific association between anatomic injury pattern and the pattern of mediator release.  相似文献   
10.
Question. To what extent does the scientific literature have an impact on current clinical practice guidelines (CPGs) in trauma surgery? Methods. We searched for CPGs on the initial management of multiply injured patients and assessed the quality of literature search and appraisal within these CPGs. Secondly, we compiled a list of all medical journal with relevance to prehospital trauma care. Lastly, we performed a handsearch for randomised controlled trials (RCTs) in some of the German not in Medline indexed traumatological journals. Results. We identified 22 CPGs of varying methodological quality. The American guidelines scored highest. Only 21 of the 38 journals (55%) in the field of prehospital trauma surgery were indexed in Medline, while 6 were covered only by Embase and 11 were indexed in neither of both databases. Handsearching four non-indexed German journals identified nearly 200 RCTs. Conclusion. Information flow between clinical research and CPG development remains difficult. Thoroughly performed literature searches have an important role in CPG development.  相似文献   
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