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11.
The potential toxicity of organic extracts from 12 seawater samples from each of 24 sampling sites, collected during 1999-2001 along the Adriatic coast, Croatia, was analyzed with the Microtox toxicity bioassay. The results were consistent with the usefulness of Microtox for the detection of accidental toxic events. To determine the water quality of selected areas, cluster analysis for discrimination between groups with similar toxicity load and water quality index as a base for the ranking of sampling sites was introduced. Based on our experimental data, five classes of the quality index were defined, and so areas were ranked in five categories (excellent, good, fair, poor, and very poor) according to their potential toxic influence. The water quality of selected sites for the potential toxicity of organic extracts could be described as excellent at one sampling site, good at 15 sampling sites, and fair at eight sampling sites. Poor and very poor seawater quality was not detected.  相似文献   
12.
Dr. B. P. Hanson  B. Kopjar 《Der Chirurg》2003,74(11):1034-1039
In the context of comparative clinical studies in surgery and in orthopedic surgery different therapies, techniques, or implants have been compared. Recent scientific publications mainly mention clinical outcome measurements such as fracture union, ROM, infection rate, as well as patient-related criteria such as pain or return to work (RTW) in order to evaluate the success of the treatment. It becomes obvious that more often than not the term "return to work" is not clearly defined. It is not mentioned who measures which criteria at which point in time, nor are part-time occupation, job change, or training on a new job part of the considerations.  相似文献   
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OBJECTIVE: We present the incidence and results of treatment of symptomatic physiologic hydronephrosis in 3,400 pregnant women. METHODS: We analyzed 103 consecutive women who presented with clinical signs and symptoms related to the upper urinary system. Renal sonography, urinalysis, serum creatinine levels, white blood cell (WBC) count, and urine culture were done in all patients at first visit and repeated at least once a month until 1 month after delivery. In patients who manifested acute pyelonephritis, urinalysis, WBC count, erythrocyte sedimentation rate and C-reactive protein levels were repeated every 3 days until normalization, and urine culture as well as renal sonography were performed once a week until 1 month after delivery. Conservative measures (positioning, analgesia, antibiotics) were performed in all patients with symptomatic physiologic hydronephrosis. If the patient's condition was refractory to medical management, drainage of the ureter with a double pigtail stent was performed. RESULTS: Conservative measures were successful in 97 (94%) of 103 patients but 6 (6%) patients had ongoing signs and symptoms of acute pyelonephritis progressing to urosepsis. In all of them, antibiotics were continued and a double pigtail stent was placed resulting in fast regression of symptoms, curing of renal infection and progress of the pregnancies to the term with vaginal delivery. CONCLUSIONS: Symptomatic hydronephrosis in pregnancy can be treated conservatively. If the patient's condition is refractory to medical management, an internal drainage with double pigtail stent may be necessary.  相似文献   
16.
Bilitranslocase is a plasma membrane carrier firstly identified on the sinusoidal (vascular) domain of liver cells and later on also in the gastric epithelium. It transports diverse organic anions, such as bilirubin, some phthaleins and many dietary anthocyanins, suggesting that it could play a role both in the absorption of flavonoids from dietary sources and in their hepatic metabolism. This work was aimed at characterising the interaction of bilitranslocase with flavonols, a flavonoid sub-class. The results obtained show that, contrary to anthocyanins, flavonol glycosides do not interact with the carrier, whereas just some of the corresponding aglycones act as relatively poor ligands to bilitranslocase. These data point to a clear-cut discrimination between anthocyanins and flavonols occurring at the level of the bilitranslocase transport site. A quantitative structure-activity relationship based on counter propagation artificial neural network modelling was undertaken in order to shed light on the nature of flavonoid interaction with bilitranslocase. It was found that binding relies on the ability to establish hydrogen bonds, ruling out the involvement of charge interactions. This requisite might be at the basis of the discrimination between anthocyanins and flavonols by bilitranslocase and could lie behind some aspects of the distinct pharmacokinetic properties of anthocyanins and flavonols in mammals.  相似文献   
17.
Sterigmatocystin (STC) and 5-methoxysterigmatocystin (5-M-STC) are mycotoxins produced by common damp indoor Aspergilli series Versicolores. Since both STC and 5-M-STC were found in the dust of indoor occupational and living areas, their occupants may be exposed to these mycotoxins, primarily by inhalation. Thus, STC and 5-M-STC were intratracheally instilled in male Wistar rats using doses (0.3 mg STC/kg of lung weight (l.w.); 3.6 mg 5-M-STC/kg l.w.; toxin combination 0.3 + 3.6 mg/kg l.w.) that corresponded to concentrations detected in the dust of damp indoor areas in order to explore cytotoxicity, vascular permeability, immunomodulation and genotoxicity. Single mycotoxins and their combinations insignificantly altered lactate-dehydrogenase activity, albumin, interleukin-6, tumor necrosis factor-α and chemokine macrophage inflammatory protein-1α concentrations, as measured by ELISA in bronchioalveolar lavage fluid upon 24 h of treatment. In an alkaline comet assay, both mycotoxins provoked a similar intensity of DNA damage in rat lungs, while in a neutral comet assay, only 5-M-STC evoked significant DNA damage. Hence, naturally occurring concentrations of individual STC may induce DNA damage in rat lungs, in which single DNA strand breaks prevail, while 5-M-STC was more responsible for double-strand breaks. In both versions of the comet assay treatment with STC + 5-M-STC, less DNA damage intensity occurred compared to single mycotoxin treatment, suggesting an antagonistic genotoxic action.  相似文献   
18.
Due to the development of resistance to antimicrobial agents, bacterium Acinetobacter baumannii is nowadays a leading cause of nosocomial outbreaks. Clinically relevant A. baumannii outside hospital settings including natural soils affected by human waste represents a public-health risk for humans and animals. The aim of this study was to investigate the potential of metal-loaded zeolites to eliminate viable A. baumannii from artificially contaminated natural soils. A. baumannii isolate was subjected to the activity of natural zeolitised tuff (NZ) and Cu-modified (CuNZ) or Ag-modified zeolite (AgNZ) in wet, slightly acidic terra rossa and slightly alkaline red palaeosol. A. baumannii survived in terra rossa and red palaeosol supplemented with 1 wt% of NZ for seven days and four months, respectively. The addition of 1 wt% of CuNZ to terra rossa and red palaeosol shortened the survival of A. baumannii to three and 14 days, respectively. The addition of 0.1 wt% of AgNZ to both soils resulted in complete removal of viable A. baumannii within 1 h of contact, while the total native heterotrophic bacterial counts remained high. Since AgNZ is prepared with a simple modification of cost-effective and environmentally friendly natural zeolite, it is a promising material for the remediation of soils contaminated with pandrug-resistant A. baumannii.  相似文献   
19.
Home injuries among adults in Stavanger, Norway.   总被引:1,自引:0,他引:1       下载免费PDF全文
Norwegian injury register data were analyzed to examine unintentional home injuries among persons ages 25 to 64 years residing in Stavanger, Norway, during 1992. A total of 782 persons received medical treatment for injury during 1992 (15.4 per 1000 population). The incidence was similar for males and females (15.8 and 14.9 per 1000 population); however, the exposure-specific injury rate was significantly higher for males (6.0 vs 4.1 per 1 million person-hours). This difference was entirely due to the much higher injury rate among males aged 25 to 44 years. The estimated first year cost (direct and indirect) per injury was $2700. Home injuries among adults appear to be an overlooked public health problem that warrants increased attention.  相似文献   
20.
Despite much research over the last few decades, there still remains considerable uncertainty as to the genetic impact of ionizing radiation on human populations, particularly at low levels. The aim of the present study was to provide data on the genetic hazards due to occupational exposure of low doses of ionizing radiation in nuclear medicine departments. The assessment of primary DNA damage in peripheral blood leukocytes of medical staff was performed using the alkaline comet assay and the data obtained were compared with the results of conventional cytogenetic biodosimetry using the chromosome aberration (CA) test. Altogether 120 subjects (60 exposed and 60 controls) participated in the study. Statistically significant increases in primary DNA damage and increased frequencies of CAs compared to controls were observed. Within the exposed population, significant inter-individual differences in DNA damage were found, indicating differences in genome sensitivity. Age and gender were not confounding factors, while smoking enhanced the levels of primary DNA damage only in control subjects, as revealed by both biomarkers studied. The present study suggests that genotoxic damage results from exposure to chronic low doses of ionizing radiation in nuclear medicine departments. Therefore, the exposed medical personnel should carefully comply with the radiation protection procedures and should minimize radiation exposure where possible to avoid potential genotoxic effects. The results obtained in this study point to the significance of biological indicators providing information on the actual risk to the radiation exposed individuals. According to our results, the alkaline comet assay and CA test are sensitive biomarkers that can be used as additional complements to physical dosimetry for assessing exposure to radiation in nuclear medicine personnel.  相似文献   
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