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At least 667 records · Page 37Linked to original sources

Evidence for a hallucinogen dependence syndrome developing soon after onset of hallucinogen use during adolescence.

This study uses latent class methods and multiple regression to shed light on hypothesized hallucinogen dependence syndromes experienced by young people who have recently initiated hallucinogen use. It explores possible variation in risk. The study sample, identified within public-use data files of the 1999 National Household Survey on Drug Abuse (NHSDA), consists of 1186 recent-onset hallucinogen users, defined as having initiated hallucinogen use within 24 months of assessment (median elapsed time since onset of use -12 to 13 months). The recent-onset users in this sample were age 12 to 21 at the time of assessment and were between the ages of 10 and 21 at the time of their first hallucinogen use. The NHSDA included items to assess seven clinical features often associated with hallucinogen dependence, which were used in latent class modelling. Latent class analysis, in conjunction with prior theory, supports a three-class solution, with 2% of recent-onset users in a class that resembles a hallucinogen dependence syndrome, whereas 88% expressed few or no clinical features of dependence. The remaining 10% may reflect users who are at risk for dependence or in an early stage of dependence. Results from latent class regressions indicate that susceptibility to rapid transition from first hallucinogen use to onset of this hallucinogen dependence syndrome might be influenced by hallucinogenic compounds taken (for example, estimated relative risk, RR = 2.4, 95% CI = 1.6, 7.6 for users of MDMA versus users of LSD). Excess risk of rapid transition did not appear to depend upon age, sex, or race/ethnicity.

Adolescent↗

Study of automated mass spectral deconvolution and identification system (AMDIS) in pesticide residue analysis.

The effects of overlapping levels and concentration ratios of overlapping components, and of scan rates of the mass spectrometer, on the capability of the automated mass spectral deconvolution and identification system (AMDIS) in pesticide residue analysis were studied. To investigate the capability of AMDIS in removing interferences from the overlapping peaks, this system was applied to data files obtained from the gas chromatography/mass spectrometry (GC/MS) analysis of two overlapping (co-eluting) pesticides (beta-HCH and PCNB) in full scan mode. Differences in overlap levels, the concentration ratios of the two overlapping components and the scan rates of the instrument were studied. When the difference in scan number of overlapping compounds was equal to 1 scan, AMDIS incompletely extracted 'purified' mass spectra but as the difference increased to 3 or more scans, complete correct spectra could be extracted. The results also show that when the scan rate was in the range of 0.4-0.90 s/scan and the concentration ratios of the target compound/interference were above 1/5, there were ideal deconvolution results for this approach. To further study the application of AMDIS to pesticide residue analysis, AMDIS was applied to the identification of pesticides spiked in real samples (cabbage and rice). Typical pesticides being evaluated were identified using AMDIS at concentrations >50 ng/g in the extracts.

Brassica↗

Semiautomated quantitation of urinary protein and creatinine.

The application of personal computers to routine tasks such as the recording and manipulation of data can greatly increase the speed and accuracy of the analyses. This report describes the use of a Macintosh computer and a BioTek microplate reader for the analysis of urinary protein and creatinine. Previously published assay methods for protein and creatinine were adapted for analysis using 96-well microplates. The adapted assays had excellent linearity (r2 = 0.99), with reduced variability compared to the previous methods. This resulted in increased sensitivity as demonstrated by 95% confidence limits. In addition, reductions of both assay materials and sample sizes were realized. The direct connection of the computer and microplate reader reduced the time needed to record absorbance measurements and perform analyses when compared to the more common protocols and methods of analysis. The assay protocols, equipment and interface, data file management, and methods of analysis are described.

Albuminuria↗

Computerized three-dimensional reconstruction reveals cerebrovascular regulatory subregions in rat brain stem.

Three-dimensional wireframe reconstructions were used to examine the relationship between the anatomical localization of electrode sites and the cerebrovascular response which was elicited by electrical stimulation of the dorsal raphe nucleus (DRN). Reconstructions of the rat brain and DRN were done from atlas plates and from Nissl-stained coronal sections (100-micron increments). Data points were entered and three-dimensional reconstructions were performed using commercially available software and a personal computer. Display of the entire brain yielded views which obscured visualization of the DRN. The data file was edited to reduce the number of contours without affecting the display resolution of the DRN. Selective display of the DRN and electronic rotation from the coronal to a sagittal view revealed a functional organization of the cerebral blood flow responses which was not apparent in two-dimensional coronal sections.

Animals↗

Craniofacial growth characteristics after bilateral fronto-orbital advancement in children with premature craniosynostosis.

The standardized bilateral fronto-orbital advanced method of osteotomy established at the University of Wuerzburg is applied in all forms of craniosynostosis except scaphocephalus. The intention behind early operation is to halt progression of the disorder and to institute the physiological direction that growth should take. The preoperative severity of the disorder, the particular symptoms of the various malformations concerned, and the postoperative course of growth were analyzed and assessed both clinically and cephalometrically using the retrospective evaluations of the file data of 131 children with various forms of craniosynostosis. In contrast to linear craniectomy and so-called lateral canthal advancement, which have sometimes been thought to lead to undesirable postoperative growth development, only 11 relapses requiring renewed operation were found postoperatively in our own study of 131 children. It became evident that the greater the severity of the malformation, the more probable it was that a relapse would occur. Fronto-orbital advancement can only affect the pathological growth pattern to a limited degree, especially when craniosynostosis is related to a syndrome. Cephalometric evaluation confirmed the limited potential for growth in the area of the anterior skull base and in the mid-face in the presence of syndrome-related brachycephaly and severe facio-craniosynostoses. In such clinical cases, compensatory growth of maxillary hypoplasia cannot be expected after fronto-orbital advancement.

Cephalometry↗

Data base management system for assisted reproduction.

A substantial amount of data are generated from a single cycle of in vitro fertilization (IVF), gamete intrafallopian transfer (GIFT), or related techniques. Maintaining an accurate and timely record of the flow of information is complicated by provision of service to many patients concurrently, diverse origins of data, and the use of donor sperm, donor oocytes, and/or cryopreservation. We have developed a data base management system for use on a network of personal computers that takes into account the volume, intricacy, and specialized features of data generated by IVF and GIFT programs. The major products of the system are (1) compact, individual patient reports on virtually all details of each treatment cycle; (2) reports on aggregate data (e.g., monthly, quarterly, or yearly); (3) automated summaries for submission to the American Fertility Society National Registry; and (4) creation of raw data files of user-specified variables that could be used for statistical analysis.

Database Management Systems↗

A topographic study of differences in the P300 between introverts and extraverts.

This paper presents results of a study to establish a link between neurocognitive psychophysiological and psychological type data through the investigation of differences in topographic auditory event-related potential (AERP) (P300) patterns in strongly introverted (n = 17) and strongly extraverted ( = 16) high school males as identified by the Myers Briggs Type Indicator. Group data files were created for the auditory event related potential task and converted to ASCII form. Amplitude values were evaluated at each scalp site. Kruskal Wallis one way analysis of variance was performed to evaluate group differences. In processing of infrequent, target stimuli, the amplitude of the P300 waveform for introverts was higher than for extraverts. When processing for non-target stimuli was subtracted from target stimuli, statistical differences were found over nine central, parietal, and occipital sites. The findings support and extend theories of biologically-based and bio-psycho-social typology.

Acoustic Stimulation↗

Designing an anaesthesia data management system for a medium size country hospital. A report of four years experiences.

By the end of 1990 the anaesthesia department of the Offenburg hospital, a 500 bed hospital, started to install a data management system in the main operating theatres. In a first phase, 23 PCs were installed in 7 induction rooms and 7 theatres as well as in the 9-bed recovery-room. All PCs are connected via ethernet to a VAX-server. The main functions of the system may be summarized as follows: 1) On-line data acquisition from the patient monitor and from the anaesthesia machine (the ventilator); 2) Off-line data entry of other variables including drugs, fluids and postop. orders as well as demographic and administrative data; 3) Data transfer from induction room to theatre and from theatre to the recovery room; 4) Printout of an automatic anaesthesia record at the end of each case--a hand-written protocol no longer required; 5) Storage of data-files on the VAX-server with possibility of reviewing individual cases and also of performing all types of statistical analysis. The set-up of the whole system including 12 ICU beds and other workstations (total of 42 PC-stations) is described as well as hard- and software used. Problems encountered during installation of hardware and experiences during implementation of software are briefly discussed. A short overview is given concerning future development.

Anesthesiology↗

A mortality study of lung cancer among swiss professional drivers: accounting for the smoking related fraction by a multivariate approach.

The mortality due to lung cancer among 'chauffeurs', who have a presumably long-term exposure to diesel exhaust fumes, was analysed. As controls, men in industrial occupations of similar socio-economic status were selected. Cases were drawn from the Swiss mortality register for the years 1979-1983. Person-years were obtained using data from the 1980 census records. These two data files were combined by occupation, age class and socio-economic status. Age adjusted incidence rates were calculated applying Poisson regression. To control for tobacco related lung cancer mortality an indirect adjustment was undertaken. Using information about the smoking habits of the people in the occupations under study, smoking-attributable lung cancer mortality was accounted for by incorporating Axelson's technique into multivariate regression modeling. The mortality ratio for lung cancer for chauffeurs with respect to the controls was 2.27, which is significantly in excess of 1:95% CI (1.99, 2.58). Other tobacco related diagnoses such as bladder cancer, esophageal cancer and ischemic heart diseases showed excess risks as well. After accounting for smoking, a slight but significant increase in lung cancer mortality remained among chauffeurs (mortality ratio 1.48, 95% CI: 1.30, 1.68). In summary, the present results do support the hypothesis that diesel exhaust is a significant cause of lung cancer.

Adult↗

Childhood leukaemia in Switzerland: comparison of different sources of data.

Since 1976 the Swiss Paediatric Oncology Groups (SPOG) has registered leukaemia cases occurring in Switzerland. The registration was set up for clinical research; however, since 1985 efforts have been made to complete the registers with cases not taking part in a clinical trial. The data of the SPOG register between 1976 and 1989 are compared to data from cancer registers and the mortality statistics of the Federal Office of Statistics. Between 1985 and 1988 the SPOG register included 91% of the cases recorded by the six cantonal registries. Compared to mortality data, registration was 100% in 1989. The SPOG data file can therefore be assumed to be complete enough to be used for epidemiological studies on incidence of leukaemias and on time trends of leukaemias in Switzerland.

Child↗

Progress of unrelated bone marrow donor search at the University Hospital of Essen (1991-1994).

The development of unrelated bone marrow donor search (UMDS) was analyzed in a retrospective single-center study covering the period from 1991 to 1994. The data files of the 285 enrolled UMDS patients were evaluated for the patients' underlying disease, HLA phenotype frequency, year of search start, UMDS duration/outcome, and the origin of identified donors. Within 3 months after UMDS start, a donor was found in 5%, 10%, 19%, and 49% of the searches started in 1991 (n = 57), 1992 (n = 73), 1993 (n = 77), and 1994 (n = 78, until September), respectively. The total UMDS success rate increased from 53% (1991 group) to 67% (1994 group), with 5% and 54%, respectively, of the accepted donors being supplied by German registries. Thus, the current UMDS procedure provides a suitable donor for the majority of the patients lacking a related donor, and the majority of the donors are now facilitated by national donor centers.

Bone Marrow↗

A high-throughput assay format for determination of nitrate reductase and nitrite reductase enzyme activities.

The authors describe a microplate-based high-throughput procedure for rapid assay of the enzyme activities of nitrate reductase and nitrite reductase, using extremely small volumes of reagents. The new procedure offers the advantages of rapidity, small sample size-nanoliter volumes, low cost, and a dramatic increase in the throughput sample number that can be analyzed simultaneously. Additional advantages can be accessed by using microplate reader application software packages that permit assigning a group type to the wells, recording of the data on exportable data files and exercising the option of using the kinetic or endpoint reading modes. The assay can also be used independently for detecting nitrite residues/contamination in environmental/food samples.

Candida↗

Estimation of individualized probabilities of developing breast cancer for Japanese women.

BACKGROUND: Projecting individualized probabilities of developing breast cancer is needed for counseling and chemoprevention for Japanese women, in whom breast cancer incidence has been rapidly increasing. METHODS: We calculated individualized probabilities of developing breast cancer within 10-20 years and until life expectancy for Japanese women by multiplying the relative risk for each risk factor combination by the cumulative risk for the reference group. The risk factors used were age at menarche, age at first delivery, family history of breast cancer, and body mass index (BMI) (in post-menopausal women). The relative risk by menopausal status for each risk factor combination was estimated from a case control study conducted at Osaka Medical Center for Cancer and Cardiovascular Diseases (OMCC), Japan. The cumulative risk of breast cancer for the reference group within 10-20 years and until life expectancy was estimated to divide the corresponding cumulative risk for Japanese women by the weighted average of the relative risk. The weight is an expected proportion of those who have each risk factor combination among the general population. The cumulative risk for Japanese women was estimated using a data file from the Osaka Cancer Registry (OCR). RESULTS: We obtained cumulative risks for any age women within a certain range according to various risk factor combinations by menopausal state. For example, the highest risk group had about a 5 times higher risk probability of developing breast cancer than the general population at initial age 40, within 10-20 years, and until life expectancy. CONCLUSION: The cumulative risk of breast cancer varied according to individuals' risk factors among Japanese women. The availability of concrete individualized risk estimation figures will be of use to health care providers in encouraging Japanese women to seek counseling and to adopt self-control of body weight as a primary preventive measure, as well as to have breast cancer screening.

Adult↗

Science, art, and artifacts: how important is quantification for the practicing physician interpreting myocardial perfusion studies?

Although considerable efforts have been directed toward improving imaging agents and imaging equipment, relatively little attention has been given to factors that optimize image interpretation. Stress myocardial perfusion images are often interpreted by visual inspection alone. This may introduce considerable inter- and intraobserver variability. Importantly, clinical usefulness of myocardial perfusion imaging may not be consistently reproduced in many laboratories using visual analysis. Relative myocardial distribution of imaging agents on either planar or single-photon emission computed tomographic images can be readily quantified and compared with normal data files by computer processing. Quantification of myocardial perfusion images provides a reproducible measure of the extent of perfusion abnormalities and defect reversibility. The extent of perfusion abnormalities has been shown to have prognostic significance. Computer quantification of myocardial perfusion images improves not only the overall diagnostic yield but also enhances reliability, accuracy, confidence, and reproducibility of interpretation.

Coronary Circulation↗

[Long-term outcome after corrective surgery of the neuro- and viscerocranium of patients with simple and syndrome-related premature craniosynostosis].

A retrospective and partly prospective study was conducted to analyse both clinically and cephalometrically the craniofacial growth pattern of patients with isolated and syndrome-related premature craniosynostosis after standardized fronto-orbital and midface advancement. The file data of 293 children with fronto-orbital advancement were evaluated over an average period of 4.4 years. In addition, lateral teleradiographies of 117 patients from this group were cephalometrically analysed. Moreover, late results of 36 children and 8 adults with midface-advancement with an average follow-up period of 4.5 years were assessed. In contrast to linear craniectomy and so-called lateral canthal advancement, in only 8.2% of cases (24 out of 293 patients) were relapses requiring reoperation found in this study after fronto-orbital advancement. The evaluations indicate that with simple forms of craniosynostosis such as trigonocephaly and plagiocephaly predominantly very good or good growth can be observed. Cephalometric evaluation confirmed the limited potential of growth in the area of the anterior skull base and in the midface in the presence of syndrome-related faciocraniosynostoses. In such cases the cephalometrically confirmed maxillary hypoplasia, which increases in severity in the following order of syndromes 'Saethre-Chotzen-Crouzon-Apert-Pfeiffer', could be influenced only to a limited degree by fronto-orbital advancement. For this reason midface advancement is of secondary importance in children with very severe anomalies. In the present evaluation, a high rate of relapse of midfacial hypoplasia was to be found in children and adolescents after this operation in accordance with other references. Therefore, the indication for Le Fort III osteotomy in the growth period should be limited.

Adult↗

Recurrent rectal cancer within the pelvis. A multicenter analysis of 123 patients and recommendations for adjuvant radiotherapy.

BACKGROUND AND PURPOSE: Recommendations for radiation ports in adjuvant radiation therapy for rectal cancer are mainly based on analysis of recurrence patterns. To evaluate whether changes in surgical technique have influenced this pattern of recurrence, a multicenter retrospective analysis was carried out on a patient population treated recently. PATIENTS AND METHODS: 123 patients were evaluated with the help of a CT-based self-developed 3-D data file system and an extensive questionnaire. Major inclusion criteria (one sufficient) for eligibility were: histological confirmation, clear bone destruction, and a positive PET scan, or at least three minor criteria: progressive soft tissue mass, invasion of adjacent organs on follow-up CT or MRI, rising tumor markers, and typical appearance in cross-sectional imaging. Clinical or serologic signs of inflammation were exclusion criteria. RESULTS: Initially, 54% of the evaluated patients were N0; in the remainder, N1 and N2 were distributed evenly. Initial T-category was T1 in 2%, T2 in 24%, T3 in 60%, and T4 in 13%, the male-to-female ratio was 2:1. Recurrent tumors were mainly situated in the posterior part of the bony pelvis as displayed in the figures. When abdominoperineal resection was compared to low anterior resection as primary operation, there was a significant difference in extension of recurrent tumors in the inferior parts of the pelvis (p<0.025 in all statistical tests applied), whereas no significant difference was found in the superior parts of the pelvis. CONCLUSION: Based on these results, a modest field size reduction in adjuvant radiotherapy for rectal cancer seems feasible, offering the perspective of a reduction in acute and late side effects.

Adult↗

[Early detection of pediatric hearing loss. Visual and automated procedures compared].

The recording of otoacoustic emissions is suitable for the detection of hearing loss in small children. The test meets the following requirements for hearing screening: it is carried out in a few minutes, specialized personnel is not necessary, the results do not depend on the vigilance of the child, and total costs are comparably low. However, the choice of a suitable device is quite essential. A test of the ILO88, ILO92, Echosensor (Otodynamics Ltd.), and Echoscreen (Madsen) devices was performed with 102 children (aged < 1 year). Additionally, a software package (Otoclass) for offline analysis of ILO88 data files was tested. The results indicate that all devices applying OAE as a screening measure was able to detect every ear (n = 25) with a hearing loss indicated by the outcome of a control BERA (stimulus level 35 dB nHL), thus reaching a sensitivity equal to 100%. The specificity of the different OAE devices depends on the underlying detection strategy. The best results were achieved with the automated Echoscreen device (95.9%) followed by the Otoclass analysis software (94.2%). The Echosensor device failed in our study to provide good specificity (77.3%). Reflex audiometry, which is favored by pediatricians in Germany, when used alone is completely inadequate as a screening method, even if conducted by a well-trained investigator. In our study, only 61.5% of the children with hearing loss were detected with reflex audiometry, and 42.7% of the children with normal hearing were misclassified. These results deviated from the results presented in ref. 13 to a large extent, as the Hanover group attested sensitivity and specificity of 100% for reflex audiometry (HNO 43, Reuter et al.). The deviating results are discussed in detail.

Acoustic Impedance Tests↗