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51.
Coles R Clements TT Nelson GJ McMillin GA Urry FM 《Journal of analytical toxicology》2005,29(6):522-527
Neonates that are exposed to cannabinoids in utero may have characteristic physical and mental developmental problems throughout their lives. The early identification of exposed neonates allows early intervention and anticipation of potential problems. Testing meconium detects maternal marijuana use over the last four months of gestation, providing a better drug exposure marker than urine. However, the distribution of metabolites in meconium is not identical to urine and analytical methods must be adapted. Both the major urine metabolite, 11-nor-9-carboxy-Delta9-tetrahydrocannabinol (9-carboxy-THC), and a minor urine metabolite, 11-hydroxy-Delta9-tetrahydrocannabinol (11-hydroxy-THC), are common in meconium. Currently published methods to extract these two metabolites for instrumental analysis are time-consuming and laborious, often involving the preparation of two fractions. This study describes a simple solid-phase extraction method and an optimized hydrolysis method that allow the preparation and analysis of both metabolites in a single extract. The limit of detection by this extraction method was 5 ng/g for both metabolites with an analytical measurement range from 10 to 500 ng/g. The recovery at 100 ng/g was greater than 62% for both analytes. The analysis of 246 cannabinoid screen positive specimens illustrated the importance of including the 11-hydroxy-THC in a meconium marijuana confirmation: 16 specimens confirmed positive for 11-hydroxy-THC only, resulting in a 6.5% increase in the positivity rate compared to 9-carboxy-THC alone. 相似文献
52.
Lewis LB Sloane DC Nascimento LM Diamant AL Guinyard JJ Yancey AK Flynn G;REACH Coalition of the African Americans Building a Legacy of Health Project 《American journal of public health》2005,95(4):668-673
OBJECTIVES: We examined availability and food options at restaurants in less affluent (target area) and more affluent (comparison area) areas of Los Angeles County to compare residents' access to healthy meals prepared and purchased away from home. We also considered environmental prompts that encourage the purchase of various foods. METHODS: We designed an instrument to assess the availability, quality, and preparation of food in restaurants. We also assessed advertisements and promotions, cleanliness, and service for each restaurant. We assessed 659 restaurants: 348 in the target area and 311 in the comparison area. RESULTS: The nutritional resource environment in our target area makes it challenging for residents to eat healthy away from home. Poorer neighborhoods with a higher proportion of African American residents have fewer healthy options available, both in food selections and in food preparation; restaurants in these neighborhoods heavily promote unhealthy food options to residents. CONCLUSIONS: Environment is important in understanding health status: support for the healthy lifestyle associated with lower risks for disease is difficult in poorer communities with a higher proportion of African American residents. 相似文献
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Lee DH Claussen GC Oh S 《The Journal of the American Academy of Orthopaedic Surgeons》2004,12(4):276-287
The electrodiagnostic study, consisting of nerve conduction studies and needle electromyography, is a useful adjunct to the clinical examination of the peripheral nervous system. The three types of nerve conduction study are motor, sensory, and mixed, of which motor is the least sensitive. Electromyography records the intrinsic electrical activity of muscle fibers, thus providing the physiologic status of muscle function. To interpret the electrodiagnostic study results, the clinician must understand the anatomic and physiologic basis of the studies. Peripheral nerve entrapment initially results in focal demyelination; thus, nerve conduction velocity slows across the site. However, with radiculopathy and nerve root compression, the nerve conduction study may be normal. Both nerve trauma and polyneuropathy show marked differences in their effect on the results of electrodiagnostic studies. 相似文献
56.
Manten GT Franx A Sikkema JM Hameeteman TM Visser GH de Groot PG Voorbij HA 《Thrombosis research》2004,114(1):19-23
INTRODUCTION: Pregnancy has recently been described as a generalized intravascular inflammatory response to the conceptus. Total fibrinogen concentrations increase during pregnancy. The percentage high molecular weight fibrinogen (HMW-Fg) of the concentration total fibrinogen is known to increase during acute-phase conditions like inflammation. Therefore, we investigated whether the percentage high molecular weight fibrinogen increases during normal pregnancy. MATERIALS AND METHODS: Eighteen healthy nulliparous women with uncomplicated pregnancies with normal course and outcome participated in this study. Five blood samples were drawn from every woman in the gestational age periods 9 to 16, 17 to 24, 25 to 33 and 34 to 42 weeks and at 12 to 20 weeks after delivery. Total fibrinogen concentrations were determined according to Clauss and the percentage high molecular weight fibrinogen was assessed by SDS-electrophoresis and densitometry after isolation of fibrinogen by precipitation. One-way analysis of variance (ANOVA) was used to evaluate differences between gestational age periods and correlation coefficients were calculated by Pearson's method. RESULTS: Total fibrinogen concentrations increased with advancing gestational age and decreased after delivery. The percentage high molecular weight fibrinogen of the total fibrinogen remained unaltered during and after pregnancy. CONCLUSIONS: During normal pregnancy, there is an increase of total fibrinogen concentrations with advancing gestational age, without a rise in percentage high molecular weight fibrinogen. After delivery, the total fibrinogen returns to baseline concentrations. 相似文献
57.
Gastrointestinal stromal tumor presenting as a pelvic mass 总被引:4,自引:0,他引:4
Gastrointestinal stromal tumors (GISTs) are c-kit-positive tumors that may arise anywhere in the tubular gastrointestinal tract. Around 5% of the cases arise elsewhere in the abdominal cavity. Tumors originating in the omentum and mesentery have been reported.A 31-year-old woman presented with pelvic pain, a palpable pelvic mass, and elevated CA-125. Imaging showed innumerable pelvic and abdominal masses. Histopathology showed a GIST that was positive for c-kit and vimentin and negative for desmin and smooth muscle actin. The patient was started on imatinib mesylate. Six months after diagnosis the tumor has remained stable.GI stromal tumors (GIST) may initially present as pelvic mass with elevated CA-125. Imatinib mesylate is the current mainstay therapy for GISTs after surgery. 相似文献
58.
We previously showed that cortical lesions in rats increase the number of subventricular zone (SVZ) cells. Here, we examined the response of the SVZ to cortical lesions in mice from 6 h to 35 days later. Whereas the total number of cells did not change, the number of cells in S-phase (bromodeoxyuridine-positive) decreased in a biphasic manner (from 6 h to day 3, and again at days 25-35). In addition, there was a delayed (days 25-35) increase in immunoreactivity for polysialylated neural cell adhesion molecule, a marker of neuroblasts. The results suggest that in mice there are rapid as well as delayed responses in the SVZ to injury of the overlying cerebral cortex. They also show that the SVZ of different mammalian species can exhibit widely divergent responses to the same brain injury. 相似文献
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Mets MB Noble AG Basti S Gavin P Davis AT Shulman ST Kazacos KR 《American journal of ophthalmology》2003,135(6):888-890
PURPOSE: To report childhood infection with Baylisascaris procyonis (raccoon round worm) manifesting as diffuse unilateral subacute neuroretinitis (DUSN) and choroidal infiltrates in association with neurologic disease (neural larva migrans).METHOD: Observational case series, one with eye manifestations of DUSN, the other with choroidal infiltrates, both with severe neurologic degeneration. RESULTS: Indirect immunofluorescence assays on serum and cerebrospinal fluid were positive for B. procyonis in one and serially positive and increasing in the other. Both children had a history of pica and raccoon exposure. CONCLUSIONS: Baylisascaris procyonis infection is associated with two cases of severe neurologic degeneration with ocular lesions: DUSN and choroidal infiltrates. Although B. procyonis is known to cause DUSN, these cases indicate that concomitant ocular migration may accompany neural larva migrans. These are the third and forth cases in the US literature of neural larva migrans due to B. procyonis with eye findings. 相似文献