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《Resuscitation》1986,13(2):115-121
Changes of neuromediators and their correction in the posttraumatic period after acute blood loss were studied experimentally in mongrel dogs. Survival of white rats was examined after heavy combined trauma during therapeutic use of exogenous cholinesterase and serotonin. Their use was studied clinically in patients with heavy combined trauma. The use of exogenous cholinesterase and serotonin in a complex of resuscitation measures permits stabilization of the functional state of the adrenal cortex and the cholinergic, adrenergic and serotoninergic systems. 相似文献
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《European journal of cancer & clinical oncology》1986,22(5):567-575
Urine samples of nursing personnel working in medical oncology divisions of several Swiss hospitals were examined for mutagenic activity. Urine samples were concentrated 100 times following XAD-2 chromatography and mutagenicity was determined using the Salmonella/mammalian microsome assay (Ames test). Apart from the urine samples of patients treated with cytostatic drugs and urine samples of nurses who are cigarette smokers, no mutagenic activity could be found. Also following exposure to an increased and defined quantity of cytostatic drugs no mutagenicity could be recovered from the urine. Four different nurses worked with cyclophosphamide, methotrexate, 5-fluorouracil, adriamycin and cis-platinum for 3–4 hr without using any protection such as gloves, masks or a vertical laminar airflow hood. Aqueous extracts of filters, through which air was pumped during the whole experiment (a personal air-sampler was fixed near the face of the test persons), were non-mutagenic. Parallel to the mutagenicity test chemical analyses were also done. The methotrexate content was determined in serum samples and the aqueous filter extracts and urine samples were examined for cis-platinum. All chemical determinations were negative. With the aid of urine concentrates of a patient treated with sub-therapeutic doses of cyclophosphamide as well as with normal urine to which single small amounts of different cytostatics (adriamycin, cyclophosphamide, cis-platinum) were added, the detection limits for the corresponding cytostatic drugs were determined and found to be in the range of 2–10 mg for cyclophosphamide and approx. 10 μg for adriamycin. Cis-platinum was lost during the passage through the XAD-2 columns. With these results at hand the sensitivity of the hitherto preferably used method (Ames test) for the monitoring of exposure to cytostatic drugs must be seriously questioned. 相似文献
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ObjectiveUsing a dynamic computed tomographic perfusion (CTP) imaging method to explore the age-related distribution of the microcirculation perfusion function in the vertebral marrow, the bone material density (BMD), and the intervertebral discal degeneration (IDD). Further, to discuss a possible causation relationship between them.MethodsOne hundred and eighty-six people were randomly enrolled by stratified sampling and grouped by age: ≤15, 16–25, 26–35, 36–45, 46–55, 56–65, 66–75, and ≥76 years old. The average CTP and BMD of the third and fourth lumbar vertebrae marrow were measured and the IDD incidence of the third-fourth vertebrae was assessed. The temporal–spatial distribution patterns of the age-related changes of the CTP, BMD, and IDD were described, and the correlations between them were calculated.ResultsThe microcirculatory perfusion function of the vertebral marrow develops to maturity by 25 years and is maintained until age 35, then declines with aging. The BMD grew to a peak from 26 to 45 years old, then decreased yearly. The IDD showed a sudden increase after 45 years of age. The CTP [BF (r = 0.806, P = 0.000), BV (r = 0.685, P = 0.005) and PMB (r = 0.619, P = 0.001)] showed strong positive correlations and CTP [TTP (r = −0.211, P = 0.322) and MTT (r = −0.598, P = 0.002)] showed negative correlations with BMD. The CTP [BF (r = −0.815, P = 0.000), BV (r = −0.753, P = 0.000) and PMB (r = −0.690, P = 0.000)] had strong negative correlations, and CTP [TTP (r = 0.323, P = 0.126) and MTT (r = 0.628, P = 0.001)] had positive correlations with the incidence of IDD.ConclusionThe decrease with aging of the microcirculatory perfusion in the lumbar vertebral marrow preceded, and is a potential causative factor for the loss of BMD and the onset of IDD. 相似文献
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《Seminars in Colon and Rectal Surgery》2014,25(3):153-157
Clostridium difficile is a spore-forming gram-positive bacterium that causes sometimes severe infections of the gut of affected individuals. The high prevalence of C. difficile infections has caused the Center for Disease Control to characterize this disease as “an immediate health threat that requires urgent and aggressive action.” A major issue with existing treatments for C. difficile is their reliance on antibiotics to kill the bacterium. These antibacterial agents cause disruptions in the gut flora that normally compete with C. difficile, rendering the gut lumen susceptible to a new round of infection or to germination of persistent C. difficile spores. This cycle of infection and recurrence underscores the need for novel approaches to the treatment and prevention of C. difficile infections. This review summarizes previous and ongoing efforts to develop active and passive immunization strategies for the prevention of primary and recurrent C. difficile infections. 相似文献
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