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61.
Blood samples from 145 Black-crowned Night-heron (Nycticorax nycticorax, BCNH) chicks (mean age 3 weeks) were taken from four island colonies (Goose (2004), Canarsie Pol (2005), Hoffman (2004 and 2005) and North Brother (2004 and 2005)) in New York Harbor in 2004 and 2005 to establish baseline health reference ranges for this species and to compare health indices of birds reared on different islands. Packed cell volume (PCV) and total solids (TS) did not differ among islands in either year. Herons raised on Hoffman Island in 2004 had lower white blood cell count (WBC), and higher activities of creatine phosphokinase (CPK), lactate dehydrogenase (LDH), aspartate amino transferase (AST), higher concentrations of potassium (K) and phosphorous (PHOS) and lower liver derived proteins (TP, prealbumin, albumin, alpha 1 globulins, alpha 2 globulins, beta globulins and gamma globulins) compared to herons from Goose and North Brother Islands. These changes suggest compromised health in chicks reared on Hoffman Island in 2004. On Hoffman in 2005, these biochemical analytes did not differ from concentrations and enzyme activities measured from birds on other islands. Although no single etiology can explain these extensive changes, it is likely that exposure to contaminants at foraging sites used by birds nesting on Hoffman and/or changes in prey availability and abundance causing birds to forage in different locations between years, led to differences measured in blood-based health indices. Avian health assessments coupled with foraging ecology serve as an excellent method for evaluating ecosystem health of the New York Harbor estuary system.  相似文献   
62.
Evidence for essential lysines in heparin cofactor II   总被引:1,自引:0,他引:1  
Covalent modification with pyridoxal 5'-phosphate was used to study the function of lysyl residues in heparin cofactor II, a heparin-dependent plasma protease inhibitor. Reduction of the Schiff base with sodium borohydride resulted in modification of 3-4 lysyl residues of heparin cofactor II at high concentrations of pyridoxal 5'-phosphate, one of which was protected in the presence of heparin. The antithrombin activity of modified heparin cofactor II was enhanced compared to the native protein. However, the heparin cofactor activity for thrombin inhibition was reduced significantly or completely eliminated in the modified protease inhibitor depending on the extent of phosphopyridoxylation. In contrast to native heparin cofactor II, the modified protease inhibitor did not bind to a heparin-agarose column. The results suggest that lysyl residues are essential for heparin cofactor activity during thrombin inhibition.  相似文献   
63.
Co-microinjection of single linearized molecules of plasmids containing the human β-globin gene (pRK1) and the herpes simplex virus (HSV) type I thymidine kinase gene (pX1) into the mouse TK? L cell nucleus results in covalent linkage between these (or derived) molecules within the nucleus as revealed by Southern blotting, plasmid rescue, and recovery of plasmid-derived DNA from a Charon 4A phage library of cellular DNA. The microinjected DNA is predominantly found as high molecular weight DNA as determined by Hirt fractionation. Southern blotting data and recombinants from the Charon 4A library suggest that the plasmid DNA is in the form of a head-to-tail linear concatamer of up to 80 copies. Passage of these microinjected cells in selective medium (HAT) results in coordinate amplification of both plasmids, which are maintained in an approx. 3:1 molar ratio of pRK1 to pX1-derived molecules. Hybridization in situ shows the DNA to be integrated on a translocation chromosome, t(4;4). Integration does not appear to be site-specific, since plasmid DNA from another microinjected cell line, C2B, appears on a different translocation chromosome, t(8?;14). Plasmid rescue experiments confirm a previous finding that passage of pBR322 DNA through eukaryotic cells may result in deletions of normally stable plasmid DNA upon subsequent transformation of E. coli. These deletions appear to occur in the bacteria, and originate in a 128 bp region between the Sal I and Hae II sites of pBR322.  相似文献   
64.
We studied the blood profile of the free-living fruit bat (Rousettus aegyptiacus) during the beginning of the activity period (around various feeding trees) and upon return to the day roost during 1994–1995. Results of the present study suggest that during winter and early spring bats are characterized by a poor physical and physiological state as reflected in the blood profile, revealing elevated urea and uric acid concentrations. It was found that at the end of the resting phase, R. aegyptiacus was in a mild state of dehydration (increased hematocrit and hemoglobin levels). At the end of activity, upon return to the day roost, both hematocrit and hemoglobin levels decreased but bats still maintained a high plasma osmolality. Several components in the blood are effected by the feeding time and show a cyclic change in concentration. The reverse relationship between glucose and triglyceride levels may indicate that glucose is the energy source during the active phase and that fat is the energy source during the resting period. The low cholesterol level in the blood reflects its absence in the fruit diet. Accepted: 5 February 1999  相似文献   
65.
Forty-two hematological and biochemical variables routinely measured in dogs as part of a preoperative protocol have been analyzed for circannual changes by analysis of variance (ANOVA) and single cosinor procedures. Data were available from up to 489 adult mongrel dogs of both sexes studied on weekdays over a 5-year span (January 5, 1987 to December 18, 1991). Dogs were housed in individual cages at 24 ± 1 °C with dog chow and tap water available ad libitum and lights on between 06:00 and 18:00 h. A single blood sample/dog was collected by jugular venipuncture between 08:00 and 09:00 h and sent to a commercial laboratory for hematological and biochemical determinations. Data were assigned to date and time of sampling and analyzed for the effect of time of year by ANOVA (across 12 months and 4 seasons), and by the least-squares fit of a precise 1-year cosine. ANOVA and single cosinor described a significant circannual time effect and rhythm for the following: total leukocytes, lymphocytes, hemoglobin, mean corpuscular hemoglobin (MCH), MCH concentration, red cell distribution width, mean platelet volume, creatinine, blood urea nitrogen (BUN), BUN/crea-tinine ratio, amylase, glucose, chloride, uric acid, direct bilirubin, total protein, albumin, globulin, albumin/globulin ratio, lactate dehydrogenase, alkaline phos-phatase, γ-glutamyltransferase, alanine aminotransferase (ALT), and aspartate aminotransferase (AST)/ALT ratio. A significant effect of season by ANOVA only was found for: Ca, Na, phosphorus, total bilirubin, hematocrit, mean corpuscular volume, and neutrophils. No significant time effect could be found at p n%ge 0.05 by either statistical method for: K, Mg, Fe, cholesterol, triglycerides, ASP, red blood cells, monocytes, eosinophils, basophils, or platelets. Acrophases occurred for the most part in either the winter or summer.  相似文献   
66.
Phytic acid’s presence in low-cost Moringa by-products effect the availability of important nutrients, diminishing the fish quality and blood composition in fish. Phytate having chelating effects with nutrients and minerals, can be reduced by the supplementation of phytase enzyme. Without the use of enzyme, plant meal may cause water pollution and decrease the fish health that results in higher culture cost. Therefore, current study was designed to check improvement in overall performance of Catla catla fingerlings fed Moringa by product-based diets supplemented with phytase (0, 300, 600, 900, 1200 and 1500, FTU/kg). All diets were integrated with non-digestible marker (Cr2O3) at the rate of 1%. The fingerlings were fed couple of times a day (4% of live wet weight). Results showed significant (p < 0.05) improvement in nutrient digestibility (i.e. EE, CP and GE), carcass composition and hematological parameters (i.e. RBCs, PLT and Hb) at 900, FTU/kg of phytase in contrast with other treatments. Moreover, phytase addition improves the water quality by reducing the nutrients leaching through feces at low cost. Current results indicated that, using mixture of Moringa seed meal and Moringa leaf meal based diet supplemented with phytase at 900, FTU/kg concentration is the most optimum level to develop a cost-effective as well as eco-friendly fish feed with maximum absorption of important nutrients and minerals in fish body resultantly high higher fish performance.  相似文献   
67.
The current work clarifies the negative effects of excess exposure to boric acid (H3BO3) as a boron-containing compound on rats and the possible ameliorative effect of melatonin (MEL). Forty rats were equally divided into 5 groups as follows: group 1 was treated as control while groups 2, 3, 4 and 5 were orally administered corn oil (0.5 ml), H3BO3 (1330 mg/kg BW), MEL (10 mg/kg BW) and H3BO3 + MEL for 28 consecutive days, respectively. At the end of the experiment, blood was sampled for biochemical and hematological analysis and tissues were collected for histopathological examination. The obtained results demonstrated that the exposure to H3BO3 induced hepatorenal dysfunctions, alterations in bone-related minerals and hormones levels, prostaglandin E2 as inflammatory mediator and hematological indices. H3BO3 induced histological alterations in the liver, kidneys, bone and skin. The co-administration of MEL with H3BO3 resulted in a significant improvement in most of the measured parameters and restoration of morpho-functional state of different organs compared to the H3BO3 group. In conclusion, the study clearly demonstrated that H3BO3- induced various adverse effects and that melatonin may be beneficial in a partial mitigating the H3BO3 and may represent a novel approach in the counteracting its toxicity.  相似文献   
68.
BackgroundTitanium dioxide "TiO2, E171″ is a widely used food additive that exists in various everyday food products all over the world together with vast applications in cosmetics and industry. However, many toxicological aspects particularly following oral exposure still unclear.MethodsHence, this study was planned to examine the effect of oral exposure of male Wistar rats to two doses of TiO2 (20 or 40 mg/kg b.wt.) through oral gavage once daily for 90 consecutive days on the blood components, immunity, cytotoxic, and genotoxic indicators.ResultsA dose-dependent leukopenia, eosinophilia, neutrophilia, and thrombocytopenia were noted. Also, the immunoglobins G (IgG) and IgM were significantly elevated in TiO2 treated rats. The phagocytic activities, lysozyme, nitric oxide, and immunoglobulin levels were significantly depleted following TiO2 exposure. A significantly reduced lymphocyte proliferation but elevated LDH activity was prominent in TiO2 treated rats. Different pathological perturbations were observed in both splenic tissue and bone marrow. A marked increase in CD4+ and CD8+ immunolabeling was evident. A significant increase in the comet variables was recorded in response to the exposure of rats to the increasing level of TiO2 at both levels.ConclusionOverall, these results indicated that TiO2 could induce hematotoxicity, genotoxic, and immunotoxic alterations with exposure for long durations.  相似文献   
69.
目的研究食蟹猴血液学及血清生化指标日间节律性变化,为正确全面评估血液学及血清生化测定结果提供一定的实验事实依据。方法在9:30(am)~10:30(am)、12:30(pm)~13:30(pm)、15:30(pm)~16:30(pm)及19:30(pm)~20:30(pm)4个时间段对12只食蟹猴(雌雄各半)采血。采用全自动血细胞分析仪及血液生化分析仪分别测定血液学及血清生化指标。利用高效液相色谱(HPLC)方法分析血浆中皮质醇含量。结果雌雄食蟹猴下午白细胞数(WBC)及尿素氮(BUN)显著升高;雌性食蟹猴下午血红蛋白(HGB)及血细胞压积(HCT)显著降低,天门冬氨酸氨基转换酶(AST)及丙氨酸氨基转换酶(ALT)活性显著升高;雄性食蟹猴下午血糖(GLU)及血浆皮质醇显著降低。结论雌雄食蟹猴血液学及血清生化部分指标存在明显的日间节律性。  相似文献   
70.
BackgroundThe present work aimed to detect the toxicological effects of green synthesized silver nanoparticles (Ag-NPs) by using Moringa Oleifera leaves extract on hematological and biochemical parameters of Oreochromis niloticus.MethodsAdult fish were exposed to two sublethal concentrations (1.95 and 3.9 ppm) of Ag-NPs against sodium selenite (0.1 ppm) and biosynthesized selenium nanoparticles (Se-NPs); 0.1 ppm; protection role for 2 and 4 weeks. Hematological parameters; erythrocyte count (RBCs), hemoglobin content (Hb), haematocrit value (Hct), mean corpuscular volume (MCV), Mean Corpuscular Hemoglobin Concentration (MCHC), leucocytes (WBCs), with differential count Micronucleus (MN) and alerted cells and biochemical parameters; aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) enzyme activities, serum protein (total protein, albumin and globulin) concentration, urea, creatinine, glucose, cholesterol (Cho) and triglyceride (Tg) were detected.ResultsThe present investigation showed that Ag-NPs in different doses led to a significant reduction (p < 0.05) in RBCs, Hb, Hct, MCV, WBCs, LYM and serum proteins concentration. However, MCHC, MN, alerted cells, NEUT, AST, ALT, ALP enzyme activities, urea, creatinine, glucose, Cho and Tg showed a significant increases (p < 0.05) when compared with control group. Sodium selenite (Se) and biosynthesized selenium nanoparticles (Se-NPs) play an optimistic role in detoxification of Ag-NPs toxicity.ConclusionThe results suggest the negative impact of Ag-NPs on hematology and biochemical parameters of fish. Moreover, Se-NPs showed a full improvement of hematological and biochemical parameters more than that of sodium selenite in elimination of Ag-NPs toxicity.  相似文献   
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