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991.
The World Wide Web (WWW) is growing in size and is becoming a substantial component of life. This seems especially true for US professionals, including social workers. It will require effort by these professionals to use the WWW effectively and efficiently. One of the main issues that these professionals will encounter in these efforts is the quality of materials located on the WWW. This paper reviews some of the factors related to improving the quality of information obtained from the WWW by social workers. 相似文献
992.
Why do WIC participants fail to pick up their checks? An urban study in the wake of welfare reform
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OBJECTIVES: This study explored whether work or immigration concerns affect women's participation in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). METHODS: The sample included women who had withdrawn from the WIC program and current WIC clients from 1 center in New York City. Logistic regression analyses were used to predict noncollection of checks; demographic characteristics, program participation, and problems with the WIC program were independent variables. RESULTS: Strong predictors of noncollection of checks were job conflicts, transportation or illness problems, and WIC receipt by the woman herself (rather than by her children). CONCLUSIONS: Employment conflicts were related to failure to pick up WIC checks; immigration concerns were not. As a means of enhancing WIC participation, flexibility is recommended in terms of center hours, locations, and staffing and program check distribution policies. 相似文献
993.
Learning curves and impact of previous operative experience on performance on a virtual reality simulator to test laparoscopic surgical skills 总被引:21,自引:0,他引:21
Grantcharov TP Bardram L Funch-Jensen P Rosenberg J 《American journal of surgery》2003,185(2):146-149
BACKGROUND: The study was carried out to analyze the learning rate for laparoscopic skills on a virtual reality training system and to establish whether the simulator was able to differentiate between surgeons with different laparoscopic experience. METHODS: Forty-one surgeons were divided into three groups according to their experience in laparoscopic surgery: masters (group 1, performed more than 100 cholecystectomies), intermediates (group 2, between 15 and 80 cholecystectomies), and beginners (group 3, fewer than 10 cholecystectomies) were included in the study. The participants were tested on the Minimally Invasive Surgical Trainer-Virtual Reality (MIST-VR) 10 consecutive times within a 1-month period. Assessment of laparoscopic skills included time, errors, and economy of hand movement, measured by the simulator. RESULTS: The learning curves regarding time reached plateau after the second repetition for group 1, the fifth repetition for group 2, and the seventh repetition for group 3 (Friedman's tests P <0.05). Experienced surgeons did not improve their error or economy of movement scores (Friedman's tests, P >0.2) indicating the absence of a learning curve for these parameters. Group 2 error scores reached plateau after the first repetition, and group 3 after the fifth repetition. Group 2 improved their economy of movement score up to the third repetition and group 3 up to the sixth repetition (Friedman's tests, P <0.05). Experienced surgeons (group 1) demonstrated best performance parameters, followed by group 2 and group 3 (Mann-Whitney test P <0.05). CONCLUSIONS: Different learning curves existed for surgeons with different laparoscopic background. The familiarization rate on the simulator was proportional to the operative experience of the surgeons. Experienced surgeons demonstrated best laparoscopic performance on the simulator, followed by those with intermediate experience and the beginners. These differences indicate that the scoring system of MIST-VR is sensitive and specific to measuring skills relevant for laparoscopic surgery. 相似文献
994.
Beloosesky Y Grinblat J Weiss A Rosenberg PH Weisbort M Hendel D 《Clinical orthopaedics and related research》2003,(413):164-169
The purpose of this study was to analyze and describe circumstances and clinical aspects of pectoralis major rupture in elderly patients compared with younger patients. Eleven patients were nursing home residents and two were community residents. All had severe pain with a large pectoral ecchymosis extending to the lateral chest wall and arm. Twelve patients experienced substantial blood loss (average, 2.3 g/dL hemoglobin), which resulted in hemodynamic decompensation in two of the patients, necessitating a blood transfusion. The most probable mechanism of injury was indirect, caused by a brisk tearing movement applied to stiff, atrophic muscle during commonly used nursing procedures for transferring, positioning, and dressing the patients. The authors suspect this injury to be more common than reported. Although surgical repair is not required in the elderly, a proper diagnosis is imperative because the injury has a severe clinical impact necessitating care and followup. 相似文献
995.
996.
Wang Q Larson PS Schlechter BL Zahid N Finnemore E de las Morenas A Blanchard RA Rosenberg CL 《International journal of cancer. Journal international du cancer》2003,106(6):923-929
We evaluated the potential utility of occult circulating tumor DNA as a molecular marker of disease in subjects previously diagnosed with breast cancer. Using 24 microsatellite markers located at sites of frequent loss of heterozygosity (LOH) or allele imbalance in breast cancer, we analyzed DNA from 16 primary tumors (Stage IIA or more advanced) and 30 longitudinally collected plasma specimens. Clinical data at the time of plasma collection were obtained. All 16 tumors were characterized by an individual pattern of LOH. LOH was detected in 12 of 30 (40%) plasma samples, taken from 8 of 14 (57%) subjects. However, the number of LOH in plasma was small (n = 15), and the mean proportion of LOH was much lower than in the tumors (0.05 vs. 0.52). Although infrequent, 12 of 15 (80%) plasma LOH were concordant with abnormalities in the paired tumors, and the mean percent LOH was higher than in normal plasmas, suggesting that they were authentic tumor-derived abnormalities. We found, despite this, no association, between plasma LOH and tumor stage or clinical status at time of blood collection (i.e., LOH was as common in subjects with no evident disease as in those with evident disease). In addition, detection of LOH was not consistent between serial samples from 5 of 11 subjects (45%), despite stable clinical conditions. No association with clinical outcome was evident, although the sample size was small. Microsatellite instability in plasma was infrequent, nonconcordant with paired tumor and inconsistent in serial samples. This pilot study suggests that identifying tumor-specific LOH in the plasma of breast cancer subjects may not be useful for detecting occult metastases or for monitoring disease. Other detection techniques may be more promising, but circulating tumor DNA may not be a sufficiently accurate reflection of breast cancer clinical status or tumor activity. 相似文献
997.
Cancer incidence in Denmark following exposure to poliovirus vaccine contaminated with simian virus 40 总被引:2,自引:0,他引:2
Engels EA Katki HA Nielsen NM Winther JF Hjalgrim H Gjerris F Rosenberg PS Frisch M 《Journal of the National Cancer Institute》2003,95(7):532-539
BACKGROUND: Early poliovirus vaccines were accidentally contaminated with simian virus 40 (SV40). In Denmark, poliovirus vaccine was administered to most children from 1955 through 1961. SV40 DNA sequences have been detected in several human malignancies, including mesothelioma, ependymoma, choroid plexus tumors, and non-Hodgkin's lymphoma. To clarify whether SV40 infection increases risk of these cancers or of cancers arising in children, we examined cancer incidence in three Danish birth cohorts. METHODS: Population-based cancer incidence data from 1943 through 1997 were obtained from the Danish Cancer Registry. The relationship between exposure to SV40-contaminated vaccine and cancer incidence was evaluated by examining incidence in birth cohorts that differed in exposure to SV40-contaminated vaccine. In addition, cancer incidence was examined in children who were 0-4 years of age before, during, and after the period of vaccine contamination. Incidence was compared using Poisson regression, adjusting for age differences. All statistical tests were two-sided. RESULTS: After 69.5 million person-years of follow-up, individuals exposed to SV40-contaminated poliovirus vaccine as infants (i.e., born 1955-1961) or children (i.e., born 1946-1952) had lower overall cancer risk (age-adjusted relative risk [RR] = 0.86, 95% confidence interval [CI] = 0.81 to 0.91 and RR = 0.79, 95% CI = 0.75 to 0.84, respectively; P<.001 for both) than unexposed individuals (i.e., born 1964-1970, after the vaccine was cleared of SV40 contamination). Specifically, SV40 exposure was not associated with increased incidence of mesothelioma, ependymoma, choroid plexus tumor, or non-Hodgkin's lymphoma. After 19.5 million person-years of follow-up, incidence of all cancers combined, of intracranial tumors, and of leukemia among children aged 0-4 years was also not associated with SV40 exposure. Ependymoma incidence was higher during the exposed period than during the unexposed period (RR = 2.59, 95%CI = 1.36 to 4.92; P =.004 versus the period before contamination); however, incidence peaked in 1969, after the vaccine was cleared of SV40. CONCLUSION: Exposure to SV40-contaminated poliovirus vaccine in Denmark was not associated with increased cancer incidence. 相似文献
998.
The synthetic retinoid RO 13-6307 induces neuroblastoma differentiation in vitro and inhibits neuroblastoma tumour growth in vivo 总被引:1,自引:0,他引:1
Ponthan F Johnsen JI Klevenvall L Castro J Kogner P 《International journal of cancer. Journal international du cancer》2003,104(4):418-424
Retinoids modulate cell proliferation, differentiation and apoptosis in a variety of tumour cells including leukaemia and neuroblastoma, a childhood tumour of the sympathetic nervous system. 13-cis retinoic acid is in clinical use against minimal residual disease in neuroblastoma, where the effect seems to depend on dose, scheduling and tumour mass. Novel retinoids are searched for, to improve potency and lower toxicity. We investigated the effect of the synthetic retinoid Ro 13-6307 on neuroblastoma growth in vitro on SK-N-BE(2) and SH-SY5Y cells. Furthermore, effects on tumour growth and the toxicity profile were investigated in a rat xenograft model. Effects of Ro 13-6307 were compared to 13-cis RA (retinoic acid) in vitro and in vivo. Neuroblastoma cells treated with 1 microM Ro 13-6307 exhibited neuronal differentiation, decreased proliferation and accumulation of cells in G1 phase in at least the same magnitude as 5 microM 13-cis RA. No apoptosis was detected in vitro. Treatment of nude rats with neuroblastoma using Ro 13-6307, 0.12 mg p.o. daily, decreased neuroblastoma growth in vivo, in terms of tumour volume during treatment and tumour weight at sacrifice (p < 0.05). In contrast, Ro 13-6307, 0.08 mg p.o. daily, resulted in no significant reduction in tumour growth. All rats treated with Ro 13-6307 gained less weight than control rats, but they exhibited no other signs of toxicity. The toxicity profile of Ro 13-6307 was similar to what we found with 13-cis RA. Our preclinical results suggest that Ro 13-6307 may be a candidate retinoid for clinical oral therapy of neuroblastoma in children. 相似文献
999.
The development and implementation of highly active antiretroviral therapy (HAART) for the treatment of the human immunodeficiency virus has revolutionised the care of patients with this disease. Despite the positive impact that antiretroviral therapy has had on the lives of individuals with HIV infection, the adverse effects, potential long-term toxicities, complexity of regimens, development of drug resistance and cost have made decisions about when to initiate HAART difficult. The benefits and risks of antiretroviral therapy vary considerably among patients at different stages of disease, mainly as a result of the irreversible destruction of the immune system that occurs as HIV infection progresses.In acute HIV infection, the primary aim of treatment is preservation and reconstitution of HIV-specific immune function. In symptomatic or late-stage disease, the goal is control of viral replication with resulting improvement in non-HIV-specific immunity, which leads to decreased morbidity and increased survival. The most controversial decision involves when to start therapy in persons with asymptomatic chronic HIV, where the benefits are less well established and may be outweighed by the drawbacks, depending on the individual patient. In all patients, the advantages and disadvantages must be considered carefully, and the readiness and ability of the individual to adhere to a complex multidrug regimen needs to be assessed before the initiation of therapy. 相似文献
1000.
Rationale. A substantial number of patients do not respond sufficiently to antidepressant drugs and are therefore often co-medicated
with lithium as an augmentation strategy. However, the neurochemical rationale behind this strategy needs to be further clarified.
Objectives. We examined the effect of chronic citalopram and subchronic lithium, alone or in combination, on (a) serum levels of citalopram
and lithium, (b) animal behaviour and (c) hippocampal serotonin (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) levels. Furthermore,
we examined the serum level of citalopram and hippocampal 5-HT following one acute citalopram injection.
Methods. Microdialysis in the freely moving animals was used to determine hippocampal 5-HT and 5-HIAA. The animal behaviour was examined
in the open field and forced swim test.
Results. We found that chronic administration of citalopram (20 mg/kg/24 h s.c.) significantly increased the 5-HT baseline relative
to vehicle-treated rats. Addition of subchronic lithium (60 mmol/kg chow pellet p.o.) to chronic citalopram therapy further
elevated the 5-HT levels. Moreover, we found acute citalopram (5 mg/kg s.c.) to increase the 5-HT level. The immobility time
in the FST and the locomotion in the OF were unaffected by any treatments.
Conclusions. The present results support the assumption that increases in hippocampal 5-HT neurotransmission may be important in the augmentatory
effect of lithium.
Electronic Publication 相似文献