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51.
达建 《中华医学教育杂志》2001,(4):41-44
本文从医学人才培养的高度,论述高校与附属医院建立非隶属关系的附属医院的过程、体会和思考,指出目前存在的问题和解决途径.对进一步深化临床教育教学改革具有重要意义. 相似文献
52.
Goraib JA Cabral JA Nogueira AR Barbosa CN Bordallo F Carvalho M Lopes JM 《Jornal de pediatria》1995,71(1):41-44
Epignathus is a congenital teratoide tumor in the oral cavity. It is extremely rare and usually lethal. The authors present a case treated successfully. Important aspects of the diagnosis, clinical management and surgical procedures are discussed. Extensive review of the literature is presented. 相似文献
53.
Oliveira EA Diniz JS Cabral AC Leite HV Colosimo EA Oliveira RB Vilasboas AS 《Pediatric nephrology (Berlin, Germany)》1999,13(9):859-864
With the increasing use of obstetric echography fetal hydronephrosis has been reported more frequently. The purpose of this
study was to identify prognostic factors associated with adverse outcome, such as renal failure and death, in fetal hydronephrosis.
One hundred and forty-eight children with fetal hydronephrosis were admitted, submitted to a systematic protocol, and prospectively
followed. Prognostic factors associated with fetal echography and clinical and laboratory findings on admission were studied.
The median follow-up was 39 months. The analysis was conducted in two steps. In a univariate analysis, variables associated
with adverse outcome were identified by the Kaplan-Meier method. The variables that were significantly associated with adverse
outcome were then included in a multivariate analysis. This analysis, using the multivariate Cox’s model, was performed to
identify variables that were independently associated with a worse prognosis. Only variables that remained independently associated
with adverse outcome were included in the final model. After final adjustment by Cox’s multivariate model, three variables
were identified as independent predictors of adverse outcome: oligohydramnios, prematurity, and glomerular filtration rate
lower than 20 ml/min. Thus, in the presence of oligohydramnios, prematurity, and abnormal renal function, the medical team
must plan appropriate follow-up for infants at health centers prepared to investigate and treat uropathies in newborns.
Received: 24 August 1998 / Revised: 7 December 1998 / Accepted: 11 December 1998 相似文献
54.
磺胺类药物的毛细管高效液相色谱与电色谱研究 总被引:4,自引:0,他引:4
目的 研究毛细管高效液相色谱(μ-HPLC)和毛细管电色谱(CEC)分离磺胺类药物,建立药物微分离分析方法。方法 用ODS柱为固定相,甲醇和2 mmol·L-1磷酸缓冲液(pH 3.0~7.0)为流动相,电压为0~-15 kV,流速为10 μL·min-1,紫外检测波长254 nm。结果μ-HPLC在甲醇-2 mmol·L-1磷酸缓冲液(30∶70),pH 3.0时5种磺胺类药物实现基线分离;CEC在电压为-5 kV,甲醇-2 mmol·L-1磷酸缓冲液(30∶70),pH 5.0时5种磺胺类药物实现基线分离。结论电渗流随甲醇含量、缓冲液浓度增加而下降,随pH值、电压的增加而增加;溶质的保留值(k)随甲醇含量、缓冲液浓度、电压的增加而下降,随电压增加下降明显的是TMP,随pH值变化较复杂。在相同条件下对5种磺胺类药物的分离,μ-HPLC需67 min,CEC只需25 min,后者更适合于磺胺类药物的快速分离分析。 相似文献
55.
56.
Identification of differentially expressed genes in aflatoxin B1- treated cultured primary rat hepatocytes and Fischer 344 rats 总被引:4,自引:1,他引:4
Harris AJ; Shaddock JG; Manjanatha MG; Lisenbey JA; Casciano DA 《Carcinogenesis》1998,19(8):1451-1458
Aflatoxin B1 (AFB1), a mutagen and hepatocarcinogen in rats and humans, is
a contaminant of the human food supply, particularly in parts of Africa and
Asia. AFB1-induced changes in gene expression may play a part in the
development of the toxic, immunosuppressive and carcinogenic properties of
this fungal metabolite. An understanding of the-role of AFB1 in modulating
gene regulation should provide insight regarding mechanisms of AFB1-induced
carcinogenesis. We used three PCR- based subtractive techniques to identify
AFB1-responsive genes in cultured primary rat hepatocyte RNA: differential
display PCR (DD-PCR), representational difference analysis (RDA) and
suppression subtractive hybridization (SSH). Each of the three techniques
identified AFB1- responsive genes, although no individual cDNA was isolated
by more than one technique. Nine cDNAs isolated using DD-PCR, RDA or SSH
were found to represent eight genes that are differentially expressed as a
result of AFB1 exposure. Genes whose mRNA levels were increased in cultured
primary rat hepatocytes after AFB1 treatment were corticosteroid binding
globulin (CBG), cytochrome P450 4F1 (CYP4F1), alpha-2 microglobulin,
C4b-binding protein (C4BP), serum amyloid A-2 and glutathione S-transferase
Yb2 (GST). Transferrin and a small CYP3A-like cDNA had reduced mRNA levels
after AFB1 exposure. Full-length CYP3A mRNA levels were increased. When
liver RNA from AFB1-treated male F344 rats was evaluated for transferrin,
CBG, GST, CYP3A and CYP4F1 expression, a decrease in transferrin mRNA and
an increase in CBG, GST, CYP3A and CYP4F1 mRNA levels was also seen.
Analysis of the potential function of these genes in maintaining cellular
homeostasis suggests that their differential expression could contribute to
the toxicity associated with AFB1 exposure.
相似文献
57.
Effect of genetic modification of acute inflammatory responsiveness on tumorigenesis in the mouse 总被引:1,自引:3,他引:1
58.
Sarah B. Laditka PhD ; James N. Laditka DA PhD ; Kevin J. Bennett MS PhD ; Janice C. Probst PhD 《The Journal of rural health》2005,21(2):158-166
CONTEXT: Pregnancy complications affect many women. It is likely that some complications can be avoided through routine primary and prenatal care of reasonable quality. PURPOSE: The authors examined access to health care during pregnancy for mothers insured by Medicaid. The access indicator is potentially avoidable maternity complications (PAMCs). Potentially avoidable maternity complications are often preventable through routine prenatal care, such as infection screening and treatment. The authors examined the risks of potentially avoidable maternity complications among rural and urban hospital deliveries for groups of mothers defined by race or ethnicity. METHODS: Data are from the year 2000 Nationwide Inpatient Sample (NIS). The stratified sample represents all discharges from 20.5% of community hospitals in the United States. The Nationwide Inpatient Sample identifies hospital locations, but not patients' areas of residence. Analyses, which accounted for the sample design, included calculation of potentially avoidable maternity complication rates by race or ethnicity, chi2, t tests, and multivariate logistic regression. FINDINGS: Within groups defined by race or ethnicity, unadjusted rates for potentially avoidable maternity complications did not differ significantly by hospital location. Holding other factors constant, potentially avoidable maternity complications were less common in rural hospitals than in urban hospitals (odds ratio, 0.78; CI, 0.62 to 0.99). In rural hospitals, African Americans had notably higher risk for potentially avoidable maternity complications than did non-Hispanic whites (odds ratio, 1.72; CI, 1.26 to 2.36). In urban hospitals, risk of potentially avoidable maternity complications was not significantly higher for African Americans. Hispanics and Asians had notably lower risks of potentially avoidable maternity complications in urban hospitals than did non-Hispanic whites. CONCLUSIONS: Providers and policymakers should work to reduce the risks of potentially avoidable maternity complications for African American women in rural areas who are insured by Medicaid. 相似文献
59.
Pedro Cabral 《European journal of paediatric neurology》2006,10(2):66-77
Attention deficit disorder (AAD) and attention deficit/hyperactivity disorder (ADHD) are very frequent and protean developmental disorders without a definite biologic marker. This review proposes a framework to understand the enlarged spectrum of its manifestations based on current knowledge of the mechanisms underlying arousal and attention variations during sleep/wake cycle. The neuro-modulation's pivotal role in this process as well as in the fine tuning of synaptic architecture during development must be taken into account when trying to understand the marked fuzziness of the symptoms and the very high prevalence of reported co-morbidities. The series of related interactions includes a cyclic deactivation of the dorso-lateral portion of the prefrontal cortex (DLPFC) during sleep, suspending executive functions, co-occurring with rhythmic periods of decreased noradrenergic tonus. A protracted unbalance in modulation, with catecholaminergic relative deficiency, could explain less-than-optimum waking DLPFC activation and the most important manifestations of ADD. Beside the well documented dopaminergic effects of stimulant medication used in ADD and ADHD, a more important role must be assigned to noradrenaline (NA). At this light hyperactivity and impulsivity are less important dimensions. Rather, an attention deficit spectrum disorder should probably be regarded as a complication of a core defect in prefrontal cortex dependent inhibitory control, underlying inattention. 相似文献
60.