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41.
The affect of negative thermal stress on hematological variables at rest, and during submaximal (sub ex) and maximal exercise (max ex) were observed for young males who volunteered in two experimental sessions, performed in cold (0°C) and in normal room temperature (20°C). At rest, hematological variables such as RBC and derivates Hb and Hct were significantly increased (P<0.05) during cold stress exposure, while plasma volume decreased. The findings of this study suggest that the major factor inducing hypovolemia during low thermal stress can be imputed to local plasma water-shift mechanisms and especially to a transient shift of plasma water from intrato extravascular compartments. Rest values for WBC and platelets (Pla) were also slightly increased during cold stress exposure. However this increase can partly be related to hemoconcentration but also to the cold induced hyperventilation activating the lung circulation. Maximal exhaustive exercise induced, in both experimental temperatures, significant (P<0.05) increments of RBC, Hb, Hct, and WBC while plasma volume decreased. However, Pla increase was less marked. On the other hand, cold stress raised slightly the observed variations of the different hematological variables. Submaximal exercise induced a similar, though non-significant, pattern for the different hematological variables in both experimental conditions. Observed plasma volume ( PV%) reduction appears during exercise. However cold stress induced resting plasma volume variations that are transferred at every exercise level. Neither exercise nor cold inducement significantly modified the hematological indices (MCH, MCV, MCHC). In conclusion hematological variables are affected by cold stress exposure, even when subjects perform a physical activity.  相似文献   
42.
We have used 16 human × mouse somatic cell hybrids containing a variable number of human chromosomes to demonstrate that the human α-globin gene is on chromosome 16. Globin gene sequences were detected by annealing purified human α-globin complementary DNA to DNA extracted from hybrid cells. Human and mouse chromosomes were distinguished by Hoechst fluorescent centromeric banding, and the individual human chromosomes were identified in the same spreads by Giemsa trypsin banding. Isozyme markers for 17 different human chromosomes were also tested in the 16 clones which have been characterized. The absence of chromosomal translocation in all hybrid clones strongly positive for the α-globin gene was established by differential staining of mouse and human chromosomes with Giemsa 11 staining. The presence of human chromosomes in hybrid cell clones which were devoid of human α-globin genes served to exclude all human chromosomes except 6, 9, 14 and 16. Among the clones negative for human α-globin sequences, one contained chromosome 2 (JFA 14a 5), three contained chromosome 4 (AHA 16E, AHA 3D and WAV R4D) and two contained chromosome 5 (AHA 16E and JFA14a 13 5) in >10% of metaphase spreads. These data excluded human chromosomes 2, 4 and 5 which had been suggested by other investigators to contain human globin genes. Only chromosome 16 was present in each one of the three hybrid cell clones found to be strongly positive for the human α-globin gene. Two clones (WAIV A and WAV) positive for the human α-globin gene and chromosome 16 were counter-selected in medium which kills cells retaining chromosome 16. In each case, the resulting hybrid populations lacked both human chromosome 16 and the α-globin gene. These studies establish the localization of the human α-globin gene to chromosome 16 and represent the first assignment of a nonexpressed unique gene by direct detection of its DNA sequences in somatic cell hybrids.  相似文献   
43.
Rates of 24Na and 42K entry into dog red blood cells were found to be strongly influenced by cell volume. The kinetics of isotope movement were complex, and the cells were not in a steady state. By applying a simple, two-compartment equation to the early times points, values for flux were calculated and corrected for the changes in surface/volume ratio which occur when cells are shrunken or swollen. Curves were thus generated showing Na and K influx as functions of cell water content. A reinvestigation of the effects of adrenalectomy showed that all the observd changes in Na flux could be explained on the basis of alterations in red cell volume.  相似文献   
44.
Hematologic and serum chemistry values are presented for adult and juvenile red ruffed lemurs (Varecia variegata rubra) and black and white ruffed lemurs (Varecia variegata variegata) maintained in a zoological collection. Hematologic and serum chemical values are compared between age groups and subspecies and with other primate species. Elevated hematocrit, total protein, and serum albumin values were noted. Significant differences in cholesterol, total protein, and serum albumin values between the two age groups are discussed.  相似文献   
45.
The combined effects of two synthetic insecticides on a wide array of biomarkers in the freshwater fish Piaractus mesopotamicus were studied. Fish were exposed to sublethal concentrations of endosulfan (ED), lambda-cyhalothrin (LC), and the combination of both pesticides for 96 h. The set of analyzed biomarkers included morphometric and hematological parameters, transaminases and alkaline phosphatase activities, antioxidant enzymes activities and oxidative damage biomarkers measured in gills, liver, kidney, brain and muscle. According to the principal component analysis, the most significant effects were produced by the ED–LC combination. So, the mixture of both insecticides produced an increase in the liver-somatic index, hematological changes related to immunological biomarkers (increased white blood cells count, and alterations in the differential leukocytes count), decreased liver transaminases activity, antioxidant enzymes induction in almost every tissue, and lipid peroxidation levels increases in liver, kidney and brain of exposed fish. Our results suggest deleterious effects of ED and LC insecticides in combination, and support the usefulness of the multi-biomarker approach for the characterization of toxicological mechanisms induced by pesticides.  相似文献   
46.
Twenty-five clinical and biochemical parameters were determined on 17 normal, male, laboratory-bred Bolivian squirrel monkeys (Saimiri sciureus). Parallel hematologic parameters were conducted. The correlation of biochemical and hematological observations and the distribution characteristics, range, and standard error of the mean were determined. The purpose of the present communication is to establish baseline biochemical values for laboratory-bred squirrel monkeys and to present a correlative comparison between selected cellular elements and major blood electrolytes.  相似文献   
47.
The knowledge of reference ranges for hematologic, biochemical, and blood gas parameters in the different species and the influence of breed and age on them is a fundamental tool for the clinician. For this reason, the aim of this study was to evaluate the age-related changes of hematologic and biochemical parameters in Martina Franca donkey foals during the first 3 weeks of life and of blood gases during the first 24 hours of age. Fifteen healthy donkey foals were enrolled; blood samples were collected from each foal at 10 minutes after birth, 1 hour after the first and second suckles, 12 and 24 hours after birth, daily from Day 2 to 7, and at Days 10, 14, and 21 of life. Erythrocytes, leukocytes, and platelets counts were assessed; also metabolic (alanine aminotransferase, aspartate aminotransferase, gamma glutamyl transferase, creatinphospokinase, lactate dehydrogenase, alkaline phosphatase, glucose, blood urea nitrogen, creatinine, total proteins, albumins, cholesterol, and total bilirubin) and electrolytic parameters (Ca, P, Mg, Na, K, and Cl) were evaluated. Finally, blood gases and metabolic parameters (pH, pCO2, pO2, sO2, TCO2, HCO3, lactate, and base excess) on venous blood were assessed with a portable analyzer. A statistical analysis to evaluate the influence of age and sex was performed. Several differences were found between sampling times, demonstrating that age influences these parameters. Moreover differences were found compared with data reported in literature for donkey foals of another species, horse foals, and adult donkeys. Although a great interindividual variation for some parameters exists, this study demonstrated that interval references should be addressed not only to different species, but also to specific breeds and to the neonatal period.  相似文献   
48.

Background

Algesia and inflammation are related with several pathological conditions. It is known that many drugs available for the treatment of these problems cause unwanted side effects. This study was aimed at evaluating acute toxicity and anti-inflammatory activity of Lampaya medicinalis Phil. (Verbenaceae) widely used in the folk medicine of Northern Chile against rheumatism, arthritis and body joints pain.

Results

Oral administration of hydroalcoholic extract (HAE) at the highest dose of 3000 mg/ Kg body weight resulted in no mortalities or evidence of significant behavioral changes. Histological examination revealed normal architecture and no significant adverse effects were observed on the liver, kidney, heart, lung or ovaries and testicles. The results suggest that the oral administration of hydroalcoholic extract (HAE) from Lampaya medicinalis did not produce any toxic effect in rats. Hydroalcoholic extract (HAE) significantly inhibited the carrageenan-induced rat paw edema in dose – response relationship, at test doses of 37.5, 75, 150 and 300 mg/Kg body weight. Maximum inhibition (61.98 ± 2.69%) was noted at 300 mg/Kg after 2 h of drug treatment carrageenan induced paw edema, whereas indomethacin produced 47.90 ± 1.16% of inhibition. The inhibitory values of edema at 3 h postcarrageenan were 31.04±0.75%, 40.51 ± 2.36%, 48.97 ± 1.14% and 56.87 ± 0.41% for 37.5, 75, 150, and 300 mg/kg of extract respectively. Indomethacin (10 mg/Kg) gave a percentage inhibition of 49.44 ± 1.44. HAE (300 and 150 mg/kg) induced an anti-inflammatory effect greater than (or comparable) with the effect of indomethacin from 2nd to 4th hours of the experiment.

Conclusions

Our results reveal for first time that compounds contained in the hydroalcoholic extract of Lampaya medicinalis Phil exert anti-inflammatory effect and the oral administration is safe and non toxic up to dose level 3000 mg/kg body weight. The anti-inflammatory activity may be associated with the presence of flavonoids. These findings also justify the traditional use of the plant for treating pain.  相似文献   
49.
Rhodiola imbricata is a perennial herb of the family Crassulaceae, which has significant traditional usage as medicine and is also known to biosynthesize phytochemicals such as flavonoids, coumarins and phenyl glycosides. The present investigation was aimed to estimate the hepatoprotective activity of R. imbricata rhizome acetone extract against paracetamol (2 g/kg) induced liver toxicity. Paracetamol was administered to induce hepatic damage in Wistar rats. 200 and 400 mg/kg doses of rhizome acetone extract and silymarin (25 mg/kg) were used as treatment groups. The blood samples were analyzed for biochemical markers of hepatic injury and tissue samples were subjected for estimation of liver antioxidants and histopathological studies. Analysis of the extract treated rats (400 mg/kg) showed an elevation of superoxide dismutase (0.326 units/min/mg protein), catalase (185.03 μmole of H2O2 consumed/min/mg protein), glutothione peroxidase (19.26 mg GSH consumed/min/mg protein) and reduced glutathione (16.2 μmole of GSH/mg protein). Moreover, the biochemical parameters in serum like alkaline phosphatase, serum glutamic oxaloacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT) and lipid profiles were also improved in treated groups compared to the control. The oral administration of different doses of rhizome acetone extract significantly protected the hepatic cells from damage. The hematological and biochemical parameters were also normal in extract treated rats compared to the control and standard (silymarin) groups. The HPLC analysis revealed the presence of some important phenolic compounds which could be responsible for the hepatoprotective activity. This study proved that R. imbricata could be taken as a good natural source of the hepatoprotective agent.  相似文献   
50.
We measured the hematocrit from greater flamingo chicks Phoenicopterus roseus over 4 years to test whether this blood parameter was related to the nutritional condition of chicks, as there are controversial results on whether hematocrit may be used as an index of body condition. We also tested whether hematocrit increased with chick age, as there would be an age-related increase of oxygen demand due to exercising. We found no evidences that hematocrit was related neither to the nutritional nor to the body condition of chicks. Hematocrit increased with chick age, which may be related to the increased requirements of chicks for oxygen delivery during development.  相似文献   
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