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21.
Krzysztof Ulfig Marek Korcz 《International journal of environmental health research》1994,4(4):244-253
The qualitative and quantitative (q/q) changes of keratinolytic fungi in soil mixtures with added sewage sludge were examined during a preliminary reclamation experiment. Sludge before land application was characterized by the weak growth of keratinolytic fungi. In devastated urban soil, abundant fungal growth was observed. Over a 19‐month reclamation period, decreasing frequency of Chrysosporium concurrent with the enrichment of the mixture with the geophilic dermatophytes Arthroderma quadrifidum and A. uncinatum were clearly seen. The results are discussed with respect to possible ecological factors influencing the occurrence of keratinolytic fungi in the materials examined. The public health risk associated with the application of sewage sludge for reclamation is also discussed. 相似文献
22.
L Borgatta J Watras A M Katz B E Ehrlich 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(6):2486-2489
The heart is a heterogeneous tissue composed of several cell types tailored for specialized functions. We found that intracellular channels also exhibit regional specialization. In cardiac and skeletal muscle these channels are called the calcium-release channel and are identified by activation with either calcium or caffeine and inhibition by the hexavalent cation ruthenium red. The calcium-release channel of the sarcoplasmic reticulum from the interventricular septum has a smaller conductance (31 pS vs. 100 pS) and has longer open and closed times when compared with the channel from left-ventricular free wall. An additional calcium-permeable channel with an even smaller conductance (17 pS) was found in the septum, and this channel is similar to the inositol 1,4,5-trisphosphate-gated channel from smooth muscle and different from the calcium-release channel (ryanodine receptor) from skeletal and cardiac muscle. The inositol 1,4,5-trisphosphate-activated channel may be derived from specialized conducting tissue that is relatively abundant in the septum, whereas the other calcium-release channels may be derived from regionally specialized myocardial cells in the septum and free wall. 相似文献
23.
R. Ehrlich R. J. Wenning G. W. Johnson S. H. Su D. J. Paustenbach 《Archives of environmental contamination and toxicology》1994,27(4):486-500
The identity and relative contributions of various sources of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) to recently deposited sediments collected in Newark Bay and its major tributaries were determined using polytopic vector analysis (PVA), a multivariate statistical technique relatively new in the chemometric literature. The concentrations of 2,3,7,8-substituted PCDD/Fs were assayed in eighty-one surface and near-surface sediment samples collected from the Passaic River, Hackensack River, Arthur Kill, Elizabeth River, Kill Van Kull, Port Elizabeth, and Port Newark navigation channels and Robins Reef, which is located in New York Harbor. PVA modeling revealed five predominant 2,3,7,8-substituted PCDD/F fingerprint patterns in geographically plausible distributions throughout the estuary. This was consistent with the current understanding of hydrodynamic and sedimentation conditions reported in the literature for Newark Bay. Three patterns contained 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD), which is alleged to originate from a single industrial source on the lower Passaic River. One of the fingerprints containing 2,3,7,8-TCDD was present in moderate proportions (10–20%) in surface sediments near the site, but was generally observed in low abundance (<5%) elsewhere in the estuary. A fingerprint pattern characteristic of PCDD/F profiles in effluents from municipal sewage and waste water treatment plants was widely distributed in the estuary, but reached its highest relative proportions in the Elizabeth River. A third fingerprint pattern was highest in the Arthur Kill and lower Passaic River and closely matched the residue patterns found in several types of combustion sources. A fourth finger-print pattern in Hackensack River and lower Passaic River sediment matched the PCDD/F profile reported in PCB Aroclor® formulations. A fifth fingerprint pattern matched the profile in recycled pulp and paper mill effluents and was highest in Kill van Kull and upper Passaic River sediment. The majority of PCDD/Fs in sediment from Reaches B, C, and D of Port Newark and Port Elizabeth were attributable to sediments transported via the Arthur Kill and the Kill Van Kull. These results are consistent with those previously reported using principal components analysis, which indicated that 2,3,7,8-substituted PCDD/F patterns in the sediments of Newark Bay are consistent with discharges from multiple sources. 相似文献
24.
This paper presents results of treatment of 46 consecutive patients with pseudoarthroses of the long bones treated with closed intramedullary reaming followed by intramedullary nailing. There were 22 nonunions of the tibia, 15 of the femur, 3 of the humerus and 6 of the forearm. The union occurred in 40 cases, among them in 3 of 4 treated atrophic, that gives 87% success. None of treated pseudoarthrosis of the humerus united. 相似文献
25.
The objective of this study was to elucidate the resistive, elastic, and total inspiratory muscle work and mainly the efficiency of the inspiratory muscle work in still standing and in exercising dogs. In 180 experiments with nine mongrel dogs, respiratory and circulatory functions were recorded at rest and during a 1.5-mph walk on a treadmill belt which was inclined by 9 degrees. Each dog had been trained and surgically prepared before the series of experiments started. An electronic pressure transducer together with a fluid-filled catheter was attached to the ribs at the midthoracic level. Airflow was monitored with a pneumotachygraph attached to a face mask. Aortic flow was monitored with an electromagnetic flow transducer. Catheters in the atria, the ventricles, and the pulmonary and systemic vessels were used to determine hemodynamic parameters and blood gas levels. All recorded and all derived functions were evaluated by a dedicated computer. At rest, resistive inspiratory work (0.98 kg cm) was smaller than elastic work (1.36 kg cm). Elastic work did not change with exercise but resistive work increased to 1.46 kg.cm. The increase of total work from 2.33 kg.cm at rest to 2.79 kg.cm during exercise did not reach significance. Inspiratory power increased with exercise. Estimated diaphragmatic oxygen consumption increased from 2.23 ml/min at rest to 3.64 ml/min during exercise. It was 1.6 percent of the total oxygen consumption at rest and 1.7 percent of the total oxygen consumption during exercise. The estimated efficiency of the work of inspiratory muscles was 15.8 percent at rest and 25.8 percent during exercise. These values did not vary substantially between different animals. 相似文献
26.
Antidepressant-like effects of trazodone on a behavioral screen are mediated by trazodone, not the metabolite m-chlorophenylpiperazine 总被引:1,自引:0,他引:1
Trazodone is an atypical antidepressant drug (i.e. blocks neither monoamine uptake nor monoamine oxidase) which tests as an antidepressant drug on the differential-reinforcement-of-low-rate 72-s (DRL 72-s) schedule of reinforcement by increasing the reinforcement rate and decreasing the response rate. m-Chlorophenylpiperazine (m-CPP) is a 5-HT1B and 5-HT1C agonist, weak 5-HT2 antagonist, and trazodone metabolite. It has been suggested that formation of m-CPP is responsible for the antidepressant action of trazodone. Administration of m-CPP (1-10 mg/kg i.p.) 60, 30 or 10 min before the behavioral session did not mimic the reinforcement rate-increasing effects of trazodone (10-20 mg/kg i.p.) on rats performing under the DRL 72-s schedule of water reinforcement. Pretreatment with proadifen (50 mg/kg i.p.), an inhibitor of trazodone metabolism, caused a greater than 30-fold leftward shift in the dose-response curve for both the reinforcement rate and the response rate. These results suggest that the parent compound and not the trazodone metabolite m-CPP, mediates the antidepressant-like effects of trazodone on DRL 72-s behavior. 相似文献
27.
Thirty-six Australian Aboriginal children with urolithiasis were reviewed. Males dominated the series. The age distribution ranged from 8 months to 12 years and nearly 70% were 2 years or younger. Thirty-five patients had upper tract stones. Ultrasound was diagnostic in 35 patients and was falsely negative in one. Dietary factors, dehydration and recurrent diarrhoea are incriminated in the aetiology, because ammonium urate and oxalate were the main constituents of the stones. Malformations of the urinary tract were rare and known metabolic disorders were not seen. Chemical dissolution of the stones was found to be a safe and effective adjuvant in the management of urate stones. 相似文献
28.
29.
J I Wolfsdorf S Ehrlich H S Landy J F Crigler 《The American journal of clinical nutrition》1992,56(3):587-592
To determine the optimal daytime dietary regimen for type 1 glycogen storage disease (GSD), we used uncooked cornstarch (UCS) at a basal glucose production rate (GPR) in single and divided doses, with mixed meals at 0700 and 1700 h. This regimen was compared with a 1.5 times larger single dose of UCS at 0700 h, and with dextrose at GPR at 1200 h. Two-hour UCS loads (amount equal to GPR in 2 h) given with a mixed meal at 0700 h and 180 min later maintained mean blood glucose (BG) concentrations at greater than or equal to 4.2 mmol/L for 300 min. BG was significantly greater from 240 to 300 min compared with a single 4-h UCS load, and at 300 min compared with a single 6-h UCS load. Similar effects were noted when the divided UCS regimen was given with a mixed meal at 1700 h, but not when isoenergetic amounts of dextrose were given on the same schedules with a mixed meal at 1200 h. A daytime schedule of six UCS feedings (with the three main meals and 180 min later) at GPR maintains BG at concentrations that should minimize biochemical abnormalities and optimize clinical outcome in patients with GSD. 相似文献
30.
Blanka Ríhová Jirí Strohalm Jana Prausová Katerina Kubácková Markéta Jelínková Lad'ka Rozprimová Milada Sírová Dana Plocová Tomás Etrych Vladimír Subr Tomás Mrkvan Marek Kovár Karel Ulbrich 《Journal of controlled release》2003,91(1-2):1-16
An N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer carrier containing doxorubicin and human immunoglobulin as an actively/passively targeting moiety was used in four patients with generalized breast cancer resistant to standard cytotoxic chemotherapy. The dose and time schedule were deduced from a Phase I clinical trial in which doxorubicin bound to HPMA copolymer carrier (PK1) was tested. It was confirmed that the Dox-HPMA-HuIg conjugate is stable and doxorubicin remains in the peripheral blood with a small amount also in the urine, mostly in its polymer-bound form. More than 116 biochemical, immunological and hematological parameters were determined for blood samples taken from patients 24 h, 48 h, 72 h and 1 to 11 weeks after treatment. Depending on the patient, some parameters decreased permanently or temporarily to the normal level (CRP, C3, CA 72-4, beta(2)-microglobulin, ferritin, CEA, CA 125, CD4, CD8, CE19, CD16(+)56(+), leu, ery) and some moved markedly towards physiological values (AST, ALT, ALP, GMT, CA 15-3, NSE, AFP). While the number of peripheral blood reticulocytes was significantly decreased after treatment with the classical free drug, their number was not affected or was even elevated after treatment with Dox-HPMA-HuIg. Increased absolute numbers of CD16(+)56(+) and CD4(+) cells in the peripheral blood and activation of NK and LAK cells in all patients support data obtained in experimental animals, pointing to a dual, i.e. cytostatic and immunomobilizing character of Dox-HPMA conjugates containing a targeting immunoglobulin moiety. 相似文献