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101.
102.
Elevated DNA single-strand breakage frequencies in lymphocytes of welders exposed to chromium and nickel 总被引:12,自引:2,他引:10
Werfel U; Langen V; Eickhoff I; Schoonbrood J; Vahrenholz C; Brauksiepe A; Popp W; Norpoth K 《Carcinogenesis》1998,19(3):413-418
DNA damage (alkaline filter elution) and sister chromatid exchange (SCE)
frequencies were measured in lymphocytes of 39 welders and 39 controls. The
welders showed a significantly higher rate of DNA single- strand breakages
and significantly elevated SCE values. These results are not in accordance
with those of a former study in which only DNA- protein cross-links were
measured. The different results may be explained on the basis of different
exposure levels for chromium(VI) and nickel. Both methods are not specific
but sensitive enough to measure genotoxic damage after occupational
exposure to chromium(VI) and nickel in the range of threshold values for
the workplace on a collective basis. Additionally, the results indicate
that DNA single- strand breakage and DNA-protein cross-links show different
increases depending on the exposure levels for chromium and nickel.
相似文献
103.
104.
Edith Hunt Raleigh PhD RN Marybeth Lepczyk MSN RN CS Constance Rowley MEd RN 《Journal of advanced nursing》1990,15(8):941-945
Little attention has been given to the preparation of the patient's family prior to surgery, even though nurses' clinical experience suggests that family members are often more anxious than the patient. This study explored the knowledge and anxiety of spouses and significant others of patients preparing for cardiac surgery. The subjects were selected by convenience from a preoperative class offered at the hospital where surgery was to occur. Before and after the class, the subjects completed a cardiac-surgery knowledge test and an anxiety test. The significant others were significantly more anxious than the patients prior to the class. The anxiety level of significant others was significantly reduced after the class. There were no statistically significant differences between patients and significant others on the cardiac-surgery knowledge test. These results suggest that significant others may benefit from preoperative instruction. 相似文献
105.
Van D. Reif W. Mark Eickhoff John K. Jackman Nicholas J. DeAngelis 《Pharmaceutical research》1987,4(1):54-58
An automated high-performance liquid chromatography (HPLC) assay for ethinyl estradiol and norgestrel or levonorgestrel in oral contraceptive tablets was developed. Tablets were prepared for on-line injection using a solid sampler and segmented continuous flow techniques. The active components were separated from tablet excipients, impurities, and degradation products on reversed-phase C8 and C18 columns by elution with water–acetonitrile–methanol (45:35:15). A UV detector connected in series with a fluorometric detector measured the UV absorbance of levonorgestrel and norgestrel at 240 nm and the fluorescence of ethinyl estradiol at 310 nm (excitation at 210 nm). The method employed computer control of the injection system and solid sampler for synchronization of the chromatographic and segmented flow streams. The method is applicable for content uniformity and stability testing at a rate of eight samples per hour. 相似文献
106.
Kathleen Ludwikowski MS RN CS Pediatric Nurse Practitioner owner Marcia DeValk BA RN C Child Adolescent Psychiatric Nurse Consultant 《Journal of child and adolescent psychiatric nursing》1998,11(1):17-29
TOPIC. Attention-deficitlhyperactivity disorder is frequently overdiagnosed when a complete evaluation by a knowledgeable clinician is not undertaken. Because of the recent negative media campaign regarding psychos t im ulan t medication, it becomes more imperative that a thorough and accurate evaluation be completed before starting children and adolescents on psychostimulant medications.
PURPOSE. To describe the neurodevelopmental perspective in the assessment and treatment of ADHD.
SOURCES. Published literature and clinical experience.
CONCLUSION. It is useful in practice to conceptualize the dmelopmental path of children with ADHD not as disordered but as delayed, and to build on each child's strengths. The neurodmeloprnental approach provides the child psychiatric nurse a child-focused framework for assessment and development of individualized interventions. 相似文献
PURPOSE. To describe the neurodevelopmental perspective in the assessment and treatment of ADHD.
SOURCES. Published literature and clinical experience.
CONCLUSION. It is useful in practice to conceptualize the dmelopmental path of children with ADHD not as disordered but as delayed, and to build on each child's strengths. The neurodmeloprnental approach provides the child psychiatric nurse a child-focused framework for assessment and development of individualized interventions. 相似文献
107.
108.
Chlamydia trachomatis infections are among the most common sexually transmitted diseases and of great epidemiological importance world-wide. Identification of this pathogen can be difficult, and it is highly desirable to have a rapid and accurate nucleic acid based detection method. Several commercial PCR test systems are available (e.g. CobasAmplicor, Roche, Mannheim, Germany) but they require post-amplification detection by hybridization resulting in extended work-up time and possible cross-contamination. The objective of our study was to develop a routine diagnostic method for the sensitive, specific and rapid detection of C. trachomatis. The obvious choice is real-time PCR without any post-amplification procedures. The dye SYBR Green I (intercalating in dsDNA) provides a simple and fast real-time PCR in the LightCycler. Specific primer design combined with melting curve analysis allows a reliable and sensitive identification of C. trachomatis. In addition, a new commercial real-time PCR system (RealArt C. trachomatis LC PCR Reagents, artus, Hamburg, Germany) was evaluated, that combines sequence-specific primers and fluorescence-labelled (FRET) 5'-nuclease probes. An internal control integrated in this system detects false negative results and erroneous PCR conditions. All results were compared with the corresponding data from an analysis using the CobasAmplicor system (Roche). (Clin 相似文献
109.
110.
TOPIC: Questions regarding how severely traumatized children may meet diagnostic criteria for an accurate diagnosis of posttraumatic stress disorder (PTSD), the comorbidity of PTSD with many other psychiatric illnesses, and the possibility that PTSD is not a valid diagnostic formulation as it has been applied to children and adolescents demonstrate that the currently held concept of PTSD may not be operationally sound. PURPOSE: To explore recent empirical studies to demonstrate the current state of controversy and postulate future direction of the conceptual framework. SOURCES: Selected published literature. CONCLUSIONS: PTSD in children and adolescents, as it is popularly understood as a conceptual framework, is found to be undergoing a conceptual metamorphosis. 相似文献