scholarly journals Arteriovenous Anastomoses in the Dermal Vasculatureof the Skin of Bos taurus Cattle, and their Relationship with Resistance to the Tick, Boophilus micro plus

1981 ◽  
Vol 34 (1) ◽  
pp. 27 ◽  
Author(s):  
AV Schleger ◽  
DT Lincoln ◽  
AS Bourne

Bos taurus cattle with high resistance to the tick Boophilus micro plus, whether free-grazing or in covered pens, had significantly more arteriovenous anastomoses (A VA) in their skin than did animals of low resistance. These differences in number of A VA associated with resistance level were most marked above the level of the sebaceous gland in the neck region, an area favoured for tick feeding. In this skin layer, the number of AVA in low-resistance animals (4�0�0�4 per 2�1 mm) was significantly lower than in animals of high resistance (12�3 � 2�2 per 2�1 mm) while the mean value for the naive animals (8�2 � 1 �9 per 2�1 mm) was intermediate. No differences in morphology of AVA were detectable between the three groups using light microscopy.

1978 ◽  
Vol 29 (2) ◽  
pp. 411 ◽  
Author(s):  
KBW Utech ◽  
GW Seifert ◽  
RH Wharton

Selection and breeding for tick resistance in an Australian Illawarra Shorthorn (AIS) herd was undertaken from 1966 to 1971. Mating of half the AIS herd with a Brahman bull in 1968–69 provided a comparison of tick resistance in selected Bos taurus and crossbred B. taurus x B. indicus cattle. Parent cows and their progeny were ranked for resistance to ticks, infestations of which were acquired as a result of grazing infested pastures, and from periodical artificial infestation with cohorts of c. 20,000 larvae of Boophilus microplus. Ranking and assessment of resistance levels were based on counts of semi-engorged female ticks on the right side. Parent cows selected for high resistance consistently carried fewer ticks than cows selected for low resistance. Mating of cattle selected for high resistance produced progeny that were significantly more resistant than the progeny of cattle selected for low resistance. However, the Brahman bull, which had slightly lower resistance than the AIS bull, produced progeny with higher resistance, even when mated with AIS COWS selected for low resistance. Pregnant cows were significantly less resistant than non-pregnant cows, and lactating cows were very much less resistant than non-lactating cows. Young cows were more resistant than older cows. Calves at foot carried fewer ticks than their dams when grazing infested pastures, but after weaning they were less resistant than their parents when resistance was determined from artificial infestations. Female calves carried fewer ticks than males on almost all occasions, but differences were not significant in winter. Significant seasonal changes in resistance were demonstrated in AIS and Brahman x AIS weaner and yearling cattle. All cattle were less resistant in winter. Changes were greatest in Brahman x AN females, on which the average numbers of female ticks that matured following artificial infestations in January 1970 (summer), July 1970 (winter) and January 1971 (summer) were 151, 1046 and 95 respectively.


1994 ◽  
Vol 108 (4) ◽  
pp. 321-324 ◽  
Author(s):  
Judith M. Heaton ◽  
Andrew J. Parker

AbstractThis paper compares the physical parameters of the newer Groningen low resistance and Provox indwelling laryngectomy prostheses with the established and original Groningen device.In vitro pressure/flow profiles were determined, using specially designed apparatus, in 44 standard Groningen high resistance (GHR), 37 Groningen low resistance (GLR) and 19 Provox tracheo-oesophageal prostheses prior to insertion. GHR valves had significantly higher forward opening pressures than both the newer valves and the GHR was significantly higher than the Provox (p<0.01: Mann-Whitney U-test). The mean forward resistance of GHR was significantly higher than that of both; the Provox valve was significantly lower than that of GLR (p<0.0001: Mann-Whitney U-test). This may be of relevance with respect to patient acceptability, voice quality and effective duration of valve action.


1981 ◽  
Vol 23 (1) ◽  
pp. 89-99 ◽  
Author(s):  
D. Di Berardino ◽  
L. Iannuzzi ◽  
T. M. Bettini ◽  
D. Matassino

G,Q and R-banding pattern comparisons between the Murrah type of Bubalus bubalis L. (2n = 50) and the Holstein Friesian breed of Bos taurus L. (2n = 60) chromosomes revealed that the autosomes are similar in both species; in the former, the five pairs of submetacentrics correspond to centric fusions of chromosomes 1-29, 2-22, 8-19, 5-28 and 16-25 in the latter. Silver staining on somatic cells of buffalo revealed telomeric Ag-NORs located on six pairs of autosomes, identified as 3p, 4p, 8, 21, 23 and 24. Only one pair of nucleolus organizer chromosomes is common to both species, namely the 4p of buffalo which corresponds to the 28 of cattle. The remaining NORs are located on different pairs. Out of 18 individuals, the number of Ag-NORs per cell varied between 3 and 10, with a mean value of 6.3 ± 1.7; the mean number of nucleolar associations per cell was between 0.1 and 1.8. In the total population of 317 cells the two variables followed the binomial and the Poisson distributions, respectively, and their correlation coefficient was not statistically significant (r = +0.36). In addition to the mean number of Ag-NORs, the mean number of nucleolar associations per cell should be used for a better understanding of the differences among individuals.


Author(s):  
Noriyuki Kuwano ◽  
Masaru Itakura ◽  
Kensuke Oki

Pd-Ce alloys exhibit various anomalies in physical properties due to mixed valences of Ce, and the anomalies are thought to be strongly related with the crystal structures. Since Pd and Ce are both heavy elements, relative magnitudes of (fcc-fpd) are so small compared with <f> that superlattice reflections, even if any, sometimes cannot be detected in conventional x-ray powder patterns, where fee and fpd are atomic scattering factors of Ce and Pd, and <f> the mean value in the crystal. However, superlattices in Pd-Ce alloys can be analyzed by electron microscopy, thanks to the high detectability of electron diffraction. In this work, we investigated modulated superstructures in alloys with 12.5 and 15.0 at.%Ce.Ingots of Pd-Ce alloys were prepared in an arc furnace under atmosphere of ultra high purity argon. The disc specimens cut out from the ingots were heat-treated in vacuum and electrothinned to electron transparency by a jet method.


1987 ◽  
Vol 26 (06) ◽  
pp. 253-257
Author(s):  
M. Mäntylä ◽  
J. Perkkiö ◽  
J. Heikkonen

The relative partition coefficients of krypton and xenon, and the regional blood flow in 27 superficial malignant tumour nodules in 22 patients with diagnosed tumours were measured using the 85mKr- and 133Xe-clearance method. In order to minimize the effect of biological variables on the measurements the radionuclides were injected simultaneously into the tumour. The distribution of the radiotracers was assumed to be in equilibrium at the beginning of the experiment. The blood perfusion was calculated by fitting a two-exponential function to the measuring points. The mean value of the perfusion rate calculated from the xenon results was 13 ± 10 ml/(100 g-min) [range 3 to 38 ml/(100 g-min)] and from the krypton results 19 ± 11 ml/(100 g-min) [range 5 to 45 ml/(100 g-min)]. These values were obtained, if the partition coefficients are equal to one. The equations obtained by using compartmental analysis were used for the calculation of the relative partition coefficient of krypton and xenon. The partition coefficient of krypton was found to be slightly smaller than that of xenon, which may be due to its smaller molecular weight.


1968 ◽  
Vol 20 (01/02) ◽  
pp. 044-049 ◽  
Author(s):  
B Lipiński ◽  
K Worowski

SummaryIn the present paper described is a simple test for detecting soluble fibrin monomer complexes (SFMC) in blood. The test consists in mixing 1% protamine sulphate with diluted oxalated plasma or serum and reading the optical density at 6190 Å. In experiments with dog plasma, enriched with soluble fibrin complexes, it was shown that OD read in PS test is proportional to the amount of fibrin recovered from the precipitate. It was found that SFMC level in plasma increases in rabbits infused intravenously with thrombin and decreases after injection of plasmin with streptokinase. In both cases PS precipitable protein in serum is elevated indicating enhanced fibrinolysis. In healthy human subjects the mean value of OD readings in plasma and sera were found to be 0.30 and 0.11, while in patients with coronary thrombosis they are 0.64 and 0.05 respectively. The origin of SFMC in circulation under physiological and pathological conditions is discussed.


1996 ◽  
Vol 75 (05) ◽  
pp. 772-777 ◽  
Author(s):  
Sybille Albrecht ◽  
Matthias Kotzsch ◽  
Gabriele Siegert ◽  
Thomas Luther ◽  
Heinz Großmann ◽  
...  

SummaryThe plasma tissue factor (TF) concentration was correlated to factor VII concentration (FVIIag) and factor VII activity (FVIIc) in 498 healthy volunteers ranging in age from 17 to 64 years. Immunoassays using monoclonal antibodies (mAbs) were developed for the determination of TF and FVIIag in plasma. The mAbs and the test systems were characterized. The mean value of the TF concentration was 172 ± 135 pg/ml. TF showed no age- and gender-related differences. For the total population, FVIIc, determined by a clotting test, was 110 ± 15% and the factor VIlag was 0.77 ± 0.19 μg/ml. FVII activity was significantly increased with age, whereas the concentration demonstrated no correlation to age in this population. FVII concentration is highly correlated with the activity as measured by clotting assay using rabbit thromboplastin. The ratio between FVIIc and FVIIag was not age-dependent, but demonstrated a significant difference between men and women. Between TF and FVII we could not detect a correlation.


1966 ◽  
Vol 16 (01/02) ◽  
pp. 038-050 ◽  
Author(s):  
Ulla Hedner ◽  
Inga Marie Nilsson ◽  
B Robertson

SummaryThe plasminogen content was determined by a casein method in plasma and serum from 20 normal volunteers. The mean plasminogen content was found to be 10.1 ACU (the arbitrary caseinolytic unit defined in such a way that using a 3% casein solution and a digestion time of 20 min. at 37°C, 10 ACU gave an extinction of 0.300). No difference between serum and plasma regarding the plasminogen content was found.Plasminogen was determined in drained and drained plus washed clots prepared from 2 ml plasma. The highest values found in the drained clots were 0.9 ACU/clot and 0.2 ACU/clot in the drained plus washed clots.Plasminogen was also determined in drained and drained plus washed clots prepared from plasma with added purified plasminogen. The plasminogen was recovered in the washing fluid. According to these tests, then, purified added plasminogen is washed out of the clots.The plasminogen content of 20 thrombi obtained post mortem was also determined. The mean value was found to be 0.7 ACU/cm thrombus. Judging from our results, the “intrinsic clot lysis theory” is not the main mechanism of clot dissolution.


2017 ◽  
Vol 4 (2) ◽  
pp. 149-161
Author(s):  
Berton Sianturi

Crassocephalum crepidioides on Cornfields in Dairi Regency had been reported tobecome more difficult to control using paraquat. The objective of the research was todetermine the characteristics and the distribution of C.crepidioides resistant to paraquatin cornfields. The experiment was carried out in two steps, the first step was screeningthe population of C. crepidioides with paraquat at the recommended dose, and the secondstep, dose-response experiment for the resistance level of C. crepidioides population withdose 0, 76, 152, 304,5, 609, 1218, and 2436 g.ai /ha. In the first step experiment, paraquatdichloride was applied at 280 g.ai/ha. The treatments were arranged in a randomized blockdesign with 3 replication. The second step experiment was that the resistant populationsconfirmed in the first experiment were sprayed for their dose-response. The treatmentswere arranged in a randomized complete block design (CRBD). The results showed thatof 30 populations of C. crepidiodes, 19 populations (63.3%) were categorized to beresistant with the mortality ranging from 10.84% to 52.08%, and 11 populations (36.7%),was categorized as high resistance with mortality of 0% to 9.21%. The level ofresistance (R/S) of R-C25, R-C27, and R-C30 populations of C. crepidioides were 12,3,14,86, and 24,83 times consecutively, compared with the susceptible population. Thenumber of C. crepidioides chlorophyl leaves in susceptible populations was significantlylower than that of a resistant populations.


2017 ◽  
Vol 4 (2) ◽  
pp. 14
Author(s):  
Putri Megasari

Hepatitis has become a health problem in the world. The hepatitis virus infected many people. According to the teacher of MTsN 02 Bondowoso more than 20 students have hepatitis A viral infection. The purpose of this research was to know the differences of students' knowledge about hepatitis A before and after counseling in MTsN 02 Bondowoso 2015. This study used pre-experimental (pre-post test design). This study used stratified random sampling technique, 127 students from 270 sample involved this research,and 143 students was excluded. We used questionnaires to collect data. The results showed that the mean value of the students 'knowledge about hepatitis A before counseling in MTsN 02 Bondowoso 2015 was 83.96 with the lowest value of 37.5 and the highest value was 100. The mean value of the students' knowledge about hepatitis A after counseling in MTsN 02 Bondowoso 2015 was 93.21 with the lowest value waf 62.5 and the highest value was 100. Paired t test showed that t (-9.07) > t table (1.98), the null hypothesis (H0) was rejected. There was a difference between students' knowledge about hepatitis A before and after counseling in MTsN 02 Bondowoso 2015. This study showed that routine counseling by healthcare provider was important to prevent hepatitis A infection.; Keywords: counseling, knowledge of students, hepatitis


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