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91.
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92.
OBJECTIVES: To compare the efficacy of structured questionnaire screening and prenatal urine toxicology for the detection of substance use by pregnant women, and to describe substance use patterns in a group of women presenting to a university-based obstetric clinic. METHODS: All patients presenting to our obstetric clinic for their first prenatal visit were evaluated for evidence of current use of alcohol or any illicit substances. Nursing personnel administered an extensive questionnaire, which included detailed questions about past and current substance use patterns. Urine samples were examined by a commercial laboratory for alcohol and a number of illicit substances. Current users were defined as those who admitted use within the past 30 days or who had positive urine toxicology. RESULTS: Fifty-eight of 302 patients (19.2%) were identified as current users of alcohol or illicit substances. Only 17 of 41 women (41.5%) with toxicologic evidence of recent use admitted to current use. Only 17 of 34 (50.0%) admitting to current use had toxicology positive for any substance. Patients with a history of multiple past substance use were significantly more likely to have positive urine toxicology than those without such a history (26.1 versus 7.4%; P < .005). Among current users, multiple substance use (34.5%) and cigarette smoking (52%) were common. CONCLUSION: A screening combination of structured questionnaire and universal urine toxicology identifies more current users than either technique alone, and neither is clearly superior to the other. A history of multiple substance use may be an important indicator of current use.  相似文献   
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Body packing is a well recognized method of drug trafficking by smuggling drug containers in the gastrointestinal tract. Medical professionals might get involved with body packers after presentation by law enforcement or in case of medical emergencies such as drug overdose or mechanical intestinal obstruction due to the containers within the gastrointestinal tract. Besides the medical aspects in treating these patients, physicians must be aware of all the different legal specifics in dealing with body packers. In case of medical emergencies, drug traffickers have the legal status of regular patients with respect to professional medical discretion. The question remains of what physicians should do with the drugs after surgical removal? Even though the body packer remains the legal owner of the drugs, physicians may not return the drugs, since that constitutes the criminal offence of dealing in narcotics. Returning the drugs to law enforcement authorities is also prohibited because of professional medical discretion. The only way out of this predicament is for physicians to destroy the drugs under the observation of witnesses.  相似文献   
95.
Background: For nitrous oxide, a preconditioning effect on the heart has yet not been investigated. This is important because nitrous oxide is commonly used in combination with volatile anesthetics, which are known to precondition the heart. The authors aimed to clarify (1) whether nitrous oxide preconditions the heart, (2) how it affects protein kinase C (PKC) and tyrosine kinases (such as Src) as central mediators of preconditioning, and (3) whether isoflurane-induced preconditioning is influenced by nitrous oxide.

Methods: For infarct size measurements, anesthetized rats were subjected to 25 min of coronary artery occlusion followed by 120 min of reperfusion. Rats received nitrous oxide (60%), isoflurane (1.4%) or isoflurane-nitrous oxide (1.4%/60%) during three 5-min periods before index ischemia (each group, n = 7). Control animals remained untreated for 45 min. Additional hearts (control, 60% nitrous oxide alone%, and isoflurane-nitrous oxide [0.6%/60%, in equianesthetic doses]) were excised for Western blot of PKC-[varepsilon] and Src kinase (each group, n = 4).

Results: Nitrous oxide had no effect on infarct size (59.1 +/- 15.2% of the area at risk vs. 51.1 +/- 10.9% in controls). Isoflurane (1.4%) and isoflurane-nitrous oxide (1.4%/60%) reduced infarct size to 30.9 +/- 10.6 and 28.7 +/- 11.8% (both P < 0.01). Nitrous oxide (60%) had no effect on phosphorylation (2.3 +/- 1.8 vs. 2.5 +/- 1.7 in controls, average light intensity, arbitrary units) and translocation (7.0 +/- 4.3 vs. 7.4 +/- 5.2 in controls) of PKC-[varepsilon]. Src kinase phosphorylation was not influenced by nitrous oxide (4.6 +/- 3.9 vs. 5.0 +/- 3.8; 3.2 +/- 2.2 vs. 3.5 +/- 3.0). Isoflurane-nitrous oxide (0.6%/60%, in equianesthetic doses) induced PKC-[varepsilon] phosphorylation (5.4 +/- 1.9 vs. 2.8 +/- 1.5; P < 0.001) and translocation to membrane regions (13.8 +/- 13.0 vs. 6.7 +/- 2.0 in controls; P < 0.05).  相似文献   

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Statins, inhibitors of the enzyme 3-hydroxy-3-methylglutaryl coenzyme A reductase, are well-established agents to lower cholesterol levels and prevent cardiovascular morbidity. Independent of their lipid-lowering properties, statins have been shown to exert pleiotropic immunomodulatory effects in various animal models of human autoimmune disease. In experimental autoimmune encephalomyelitis, a murine model for multiple sclerosis, statins prevented disease onset and even reversed paralysis when treatment was initiated after experimental autoimmune encephalomyelitis was fully established. Furthermore, well-tolerated oral statins were recently shown to exert synergistic benefit in experimental autoimmune encephalomyelitis in combination with existing agents for multiple sclerosis therapy. Based primarily on these encouraging results, statins are now being tested in clinical trials as a mono-therapy for multiple sclerosis, as well as in combination with approved disease-modifying therapies.  相似文献   
98.
Alterations of blood flow contribute to major clinical complications in invasive infections such as sepsis and bacterial meningitis. As a unique feature streptococci -- in particular, Streptococcus pneumoniae, the most frequent pathogen in bacterial meningitis -- release hydrogen peroxide (H(2)O(2)) because of the absence of functional catalase. In a 6 h rat model of experimental meningitis, we studied the impact of bacterial H(2)O(2) production on regional cerebral blood flow (rCBF) and intracranial pressure (ICP). Compared to wild-type D39 pneumococci, the increase of rCBF was diminished in meningitis induced by the H(2)O(2) defective SpxB(-) mutant (maximum increase, 135% +/- 17% versus 217% +/- 23% of the individual baseline; P<0.01) or after treatment of D39-induced meningitis with H(2)O(2)-degrading catalase or with tetraethylammonium (TEA), a blocker of calcium-sensitive potassium channels, which mediate H(2)O(2)-induced vasodilation. Catalase did not significantly reduce the remaining rCBF increase caused by SpxB(-), supporting the predominant role of bacterial H(2)O(2). We conclude that in addition to host-sided mediators, bacterial-derived H(2)O(2) acts as a potent vasodilator, which accounts for a certain proportion of the early cerebral hyperperfusion in pneumococcal meningitis.  相似文献   
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We present an adenoid cystic carcinoma of the base of tongue in a 48-year-old male with a restricted chromosomal alteration by cytogenetic and spectral karyotypic analysis (SKY). SKY and G-banding analyses identified the t(6;14)(q25;q13) as the sole structural aberration in all metaphases analyzed. This finding supports a critical role for this event in the development of this tumor. The implications of chromosome 6q translocation in this case and in previously reported adenoid cystic carcinomas are highlighted and discussed.  相似文献   
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