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31.
Emerging trends are reshaping the work of school nurses and other school service personnel. With respect to direct service and consultation, school nurses increasingly are called upon to deal with psychosocial and mental health problems. Beyond that, school nurses must continue to actuate their roles as advocates, catalysts, brokers, and facilitators of the type of reforms that can effectively address barriers to student learning and promote healthy development. Continuing education is seen as key to enabling school nurses to build capacity for such roles and functions. The newly formed Center for Mental Health in Schools at the University of California, Los Angeles (UCLA) hopes to be of assistance in this respect. This presentation highlights the Center's orientation to mental health in schools and offers a draft outline for related continuing education.  相似文献   
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OBJECTIVE: Isotope ratio mass spectrometry (IRMS) is the accepted method for accurately measuring the 13CO2:12CO2 ratio in the non-invasive and non-radioactive [13C]urea breath test (13C-UBT) for Helicobactor pylori. The IRMS instrument, an expensive and highly specialized analyser, is rarely available. The objective of this project was to modify and validate the use of a simple bench-top gas chromatograph-mass selective detector (GC-MSD) for 13C-UBT. METHODS: Breath samples from 71 patients were taken at baseline and 30 min after ingestion of 100 mg [13C]urea. The breath samples were analysed using GC-MSD in the selected ion monitoring mode. The reference 13CO2:12CO2 ratio was from NBS19 obtained from the US National Institute of Standards and Technology. 13CO2:12CO2 ratios of the breath samples were determined. Excess delta per thousand (per mil, delta/thousand) of the 30 min sample over the baseline (deltadelta/thousand) of > or = 6deltadelta/thousand was considered H. pylori positive. Results from 13C-UBT and histology determined blind to each other were compared. RESULTS: The coefficient of variation of the reference 13CO2:12CO2 ratio was 0.06%. Using histology as the 'gold standard', the sensitivity (97.9%) and specificity (95.8%) of the GC-MSD 13C-UBT were comparable to those of other methods of H. pylori diagnosis. CONCLUSION: A gas chromatograph coupled to a mass selective detector that is available in many analytical and biomedical laboratories can be used for the 13C-UBT. This method will increase the availability and reduce the cost of this non-invasive, non-radioactive diagnostic test.  相似文献   
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Npt2 encodes a renal-specific, brush-border membrane Na+-phosphate (Pi) cotransporter that is expressed in the proximal tubule where the bulk of filtered Pi is reabsorbed. Mice deficient in the Npt2 gene were generated by targeted mutagenesis to define the role of Npt2 in the overall maintenance of Pi homeostasis, determine its impact on skeletal development, and clarify its relationship to autosomal disorders of renal Pi reabsorption in humans. Homozygous mutants (Npt2(-/-)) exhibit increased urinary Pi excretion, hypophosphatemia, an appropriate elevation in the serum concentration of 1,25-dihydroxyvitamin D with attendant hypercalcemia, hypercalciuria and decreased serum parathyroid hormone levels, and increased serum alkaline phosphatase activity. These biochemical features are typical of patients with hereditary hypophosphatemic rickets with hypercalciuria (HHRH), a Mendelian disorder of renal Pi reabsorption. However, unlike HHRH patients, Npt2(-/-) mice do not have rickets or osteomalacia. At weaning, Npt2(-/-) mice have poorly developed trabecular bone and retarded secondary ossification, but, with increasing age, there is a dramatic reversal and eventual overcompensation of the skeletal phenotype. Our findings demonstrate that Npt2 is a major regulator of Pi homeostasis and necessary for normal skeletal development.  相似文献   
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Ischaemia-reperfusion injury generates oxygen-derived free radicals leading to local and distant damage. A simple method of following oxidative activity is to measure the consumption of endogenous scavenging antioxidants; an enhanced chemiluminescent assay was used to study this phenomenon in 21 patients undergoing surgery for abdominal aortic aneurysm (AAA). Samples of peripheral venous blood were taken before induction of anaesthesia and then from a central venous line and the inferior mesenteric vein before, during, and after clamping of the aorta. Further specimens were taken from the central line at 2, 6 and 24 h after operation. Antioxidant concentration in the peripheral, central and inferior mesenteric blood were similar, indicating that anaesthesia and surgical dissection had no effect. Levels decreased significantly in central and inferior mesenteric blood during and after clamping, but returned to normal by 24 h. These results confirm ischaemia-reperfusion phenomena in AAA repair.  相似文献   
37.
A polymerase chain reaction (PCR) method for the rapid diagnosis of tuberculous meningitis (TBM) was used to study prospectively 47 cerebrospinal fluid (CSF) samples from 45 patients. Twenty CSF samples were from patients with clinically suspected TBM and another 27 samples came from patients without clinically suspected TBM. Mycobacterial DNA was detected in 15 CSF samples (14 from patients with clinically suspected TBM and 1 from a patient not suspected of having TBM). Of the PCR-positive samples, 4 were also positive for mycobacterial culture. However, 32 PCR-negative samples were all culture-negative. All samples were negative for the acid-fast bacillus by direct smear. The single PCR-positive patient in the clinically unsuspected TBM group was initially diagnosed as suffering from aseptic meningitis on the basis of his clinical features. The mycobacterial culture of his CSF specimen was also positive and a revised diagnosis of an aseptic type of TBM was made. The estimations of specificity and sensitivity in this study were 100% and 70% respectively. The results showed that using a PCR to detect mycobacterial DNA in CSF for the early diagnosis of TBM is not only a rapid but also an accurate method.  相似文献   
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OBJECTIVE: A line scan spectroscopic imaging method providing variable T2-weighted spectra from many small voxels along selected tissue columns was applied to study the chemical composition of hematopoietic and fatty marrow in the knees of adults and children. MATERIALS AND METHODS: Line scan Carr-Purcell-Meiboom-Gill (CPMG) spectroscopic imaging sequences were implemented on a 1.5 T clinical scanner. Variable T2-weighted proton spectra from 128 locations along 20 cm long, 5 mm2 columns oriented superiorly to inferiorly through knees were collected from eight healthy adults and eight children. RESULTS: In adult yellow marrow, olefinic protons, water, a composite lipid proton peak, and methyl/methylene protons contributed 6.4 +/- 0.4, 4.2 +/- 1.5, 7.2 +/- 0.5, and 82.2 +/- 1.9% (mean +/- SD) to the spectra, respectively. Marrow spectra were largely independent of position along the column. Marrow spectra of normal children showed distinct positional dependences. Epiphyseal marrow spectra of children (8-16 years old) resembled adult spectra but with more water (mean 15 vs. 4%). Metaphyseal marrow had higher, variable water content, reflecting the extent of marrow conversion and generally obscuring the olefinic proton peak. CONCLUSIONS: Spectroscopic imaging of columns is a time-efficient method for sampling extensive regions of bone marrow with high spatial resolution. It should prove useful for proton spectroscopic studies of hematologic pathologies and conditions requiring the monitoring of lipid composition.  相似文献   
40.
The survival of 119 colorectal cancer patients was analyzed in the light of the overexpression status of the c-myc proto-oncogene mRNA and the point mutation status of the p53 tumor suppressor gene in the primary adenocarcinoma. The presence of >3 fold overexpression of c-myc mRNA in the primary tumor was found to be associated with a better prognosis than patients who evinced no overexpression (P = 0.02, log rank analysis). Point mutation of the p53 tumor suppressor gene was found to be associated with a poorer patient prognosis (P = 0.007, log rank analysis). Endogenous levels of c-myc and point mutation of p53 both contributed independently toward a poorer patient prognosis in Cox regression modeling. The better prognosis seen in patients who overexpress c-myc was offset when c-myc overexpression was coupled with a point mutated p53 gene. These results suggest that in colorectal adenocarcinoma c-myc deregulation leads to increased apoptotic death, but that this response may be modulated by a more downstream event such as point mutation of the p53 gene.  相似文献   
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