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Biomedical subjects

K Nestler

Publications and source records attributed to K Nestler.

At least 19 recordsLinked to original sources
PubMed2002

Investigation of interfacial interaction between uncoated and coated carbon fibres and the magnesium alloy AZ91.

Unidirectionally reinforced metal-matrix composites with a fibre volume content between 63 and 68% were processed by squeeze casting using T800 H carbon fibres and the magnesium alloy AZ91. The surface of the fibres was prepared by thermal desizing of the fibres or by deposition of a pyrolytic carbon (pyC) coating. Different interfacial conditions could be identified by transmission electron microscopy (TEM) and the single-fibre push-in test. TEM confirmed the formation of needle-like phases at the fibre surface or, for coated fibres, within the pyrolytic carbon coating. During loading by the Vickers type indenter an intense response was observed for composites of coated fibres and the magnesium alloy. This could by caused by stick-slip effects within the pyrolytic carbon coating.

Journal Article↗
PubMed2001

Raman spectroscopic surface characterization of cellulose derivatives.

First results of experiments on the surface characterization of cellulose derivatives are presented. Different water contents of the surface of microcrystalline cellulose have been investigated by means of Raman spectroscopy, SERS, and environmental scanning electron microscopy (ESEM).

Journal Article↗
PubMed1991

[The content of minerals and Fe, Cu and Zn in blood plasma, in erythrocytes and in 10 different tissues of bulls, short scrotum bulls and oxen].

The concentrations of minerals (Ca, Mg, Na, K, total-P) and of trace elements (Fe, Cu, Zn) in the plasma and erythrocytes of bulls, of experimentally induced cryptorchids (Muchsen) and of oxen of the breed Holstein-Friesian and of bulls and cryptorchids of a hybrid breed with a high portion of meat-cattle were investigated. Further the concentrations in various tissues (M. semimembranosus, M. longissimus dorsi, left and right ventricle, liver, kidney, adrenal glands, lung, spleen, testis) in bulls, cryptorchids and oxen of the breed Holstein-Friesian were analyzed. The differences of some concentrations of various elements in some tissues are discussed relative to their genesis and significance.

Animals↗
PubMed1991

Solvent uptake in relation to physical activity.

The influence of lung ventilation and free fatty acids in serum on the internal exposure of organic solvents were investigated. 68 healthy male subjects were exposed 1 h at rest and during exercise to styrene, toluene or xylene. Uptake is influenced by the solvent concentration in inspired air, retention index and pulmonary ventilation. Internal exposure is characterized by venous blood concentrations and metabolites in urine. An increase in free fatty acids could be observed dependent on the internal exposure, preventing increases in the content of free fatty acids is a problem of susceptibility and medical care of exposed workers. Biological limits for the control of internal exposure are suggested.

Adult↗
PubMed1990

[Role of the occupational health service in the control of hypertension].

By a representative random sample in an order of magnitude of 5,150 employees the determination of the degree of knowledge of the hypertensives in the factory health service of metal mines showed nearly 100%. In the dispensary of the factory medical officer 64.2% were registered. 36.6% of the hypertensives were stabilised to blood pressure values below 160/95 mm Hg. Forms of therapy, cardiovascular risk factors associated with high blood pressure and effects of the working environment were investigated by means of factor and discriminance analysis with regard to the influence on the quality of the stabilisation of high blood pressure. The compliance resulted as essential limiting factor in the treatment of hypertension. 71% of the hypertensives reported a regular intake of medicaments, in which case 51% admitted to interrupt it without consulting the physician in charge when the constitution is disturbed. 4 features were determined as essential factors which have influence on the compliance: the opinion concerning the duration of the treatment of hypertension, the attitude to the intake of medicaments, the frequency of the intake of the tablets and the observation of the terms of blood pressure control. The investigation of the physician's compliance resulted, apart from an overestimation of the patient's compliance, in distinct deviations from the recommendations for diagnosis and therapy given. The compliance of nurses showed deficiencies in the standardized measurement of blood pressure.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

[Physician compliance in the treatment of hypertension].

The physician compliance is determined by knowledge, skill and behaviour. In 103 physicians working in the basic medical care investigations of the compliance were performed. Partly clear deviations from the guidelines recommended were found in the habits of diagnostics and therapy. These deviations frequently concerned even the majority of the physicians asked for. While the knowledge can relatively easily be judged according to objective criteria, the behaviour is difficult to be measured. Of 4 physicians with comparable knowledge concerning the clinical picture of hypertension the influence of the behaviour of the physician on the success of therapy was investigated during a psycho-physiologically orientated group therapy and the breath-induced relaxation training. The univariate and discriminance-analytic investigations as well as the factor analyses showed the behaviour of the physician as essentially determinating for the success of the therapy. The determination of the physician compliance gives the possibility to recognize still existing insufficiencies in the treatment of hypertension. It serves for the further optimization of the therapy of hypertension. Measures increasing the compliance among others can be derived also for the training and further training.

Adult↗
PubMed1990

[The content of Hb and the hematocrit value in blood and the total proteins, urea, glucose, free fatty acids, Na, K, Ca, Mg, Pa, Fe, Fe-binding capacity, Cu and Zn in the blood plasma of Warmblood horses during feeding with oat-hay or barley-hay rations over a period of 9 months].

4 horses (Group A) received an oat-hay ration, through 9 months running, while 3 horses (Group B) were fed a barley-hay ration over the same period of time. Blood samples were collected and examined in 4-week intervals. All values considered, no differences were found to exist between the 2 groups with regard to Hb and haematocrit in blood as well as to protein, glucose, sodium, potassium, magnesium, iron fixation capacity, copper, and zinc in blood plasma. The urea level in plasma of Group A was higher than that in Group B, values being 5.76 +/- 0.64 mmol/l and 5.14 +/- 0.72 mmol/l. The same applied to free fatty acids, values being 150 +/- 83 mumols/l in Group A and 95 +/- 42 mumols/l in Group B. Calcium was 3.10 +/- 0.27 mmol/l in Group A and 2.92 +/- 0.26 mmol/l in Group B, while the A-B difference in inorganic phosphorus amounted to 1.62 +/- 0.65 against 1.99 +/- 0.77 mmol/l. Group A was inferior to Group B also with regard to iron in plasma, values being 28.6 +/- 2.42 mumols/l against 32.8 +/- 4.62 mumol/l. Causes underlying these differences are discussed in some detail.

Animal Feed↗
PubMed1990

[The content of Hb in blood and the protein, Fe, Fe-binding capacity, Cu and Zn in blood plasma of low parity sows before and after oral iron administration].

In investigations of 51 pregnant sows, blood Hb levels above 7.45 mmol/l (mean value of 8.94 +/- 0.88) were recorded from 43 animals (Group A), while levels below that margin were recorded from eight (Group B) (mean value of 6.73 +/- 0.31). Iron levels in blood plasma of Group A were 36.9 +/- 8.07 and were thus higher (p less than 0.01) than those in Group B (28.9 +/- 5.19 mumol/l). No difference was found to exist between the two groups with regard to iron fixation capacity as well as copper and zinc in blood plasma. Oral uptake of 50, 500 or 2,000 mg of iron in the form of FeSO4.7H2O with cereal shred as morning ration by 17 or 15 sows failed to cause any increase in blood plasma iron levels, within 360 minutes from uptake. Literature data as well as the results of these analyses have supported the recommendation that Hb variations between 4.96 and 9.93 mmol/l (8-16 g/dl) should be rated as physiological in the blood of pregnant sows. The GDR Standard TGL 35,423 on "Monitoring of Metabolism on Pig Breeding and Fattening Units" should be accordingly amended.

Animals↗
PubMed1990

[Observations on the course of borderline hypertension in workers in ore mining with variable occupational body burden].

The blood pressure response of 198 ore miners--working above ground as well as underground--suffering from borderline-hypertension was checked over a period of 5 years. After a period of 5 years 40.9% of the test persons developed a hypertension in 18.7% of the miners the blood pressure returned to normal and with 40.4% it remained within the limits. No statistically significant relationship could be established between the blood pressure response and the various work loads such as the complex work load on face workers, work above ground and underground, shift work, the total time away from home, physically heavy work as well as exposure of the body or part of it to vibrations. Since the individual risk of developing hypertension, particularly with regard to people affected by borderline-hypertension, cannot be predicted the factory doctor has to provide for the adequate health care the group in question.

Adult↗
PubMed1989

[Drug compliance behavior of hypertensive patients in 3-shift work with a prescription for 3 or more single doses daily].

82 hypertensive patients with a prescription of medicaments of three and more individual doses a day who worked in the three-shift system were anonymously asked about their behaviour concerning the intake of tablets. 78% said not to have obtained any recommendations for the intake of tablets during the nightwork. 20.7% of them took antihypertensive drugs at night during the shift. 51.3% in the day-time and 28.0% did not take any tablets during the night-work. The compliance was approximately 60%, similarly as in hypertensive patients working in the one-shift system. With 3.7% the non-compliance was lowest during the night-shift. It was 22.0% during the early shift and 12.1% during the late shift. Side-effects and disturbances of the good health, respectively, during the antihypertensive treatment were stated with 14.0% and with 7.3% they appeared most frequently during the night-work. There was a statistically ascertained connection between the intake of tablets at night during work and the side-effects. They altogether appeared more infrequently, when a concrete advice was given by the physician. From this is concluded that on principle in shift-workers a treatment of the hypertension is to be aspired to with one or two individual doses a day, otherwise in a prescription of three individual doses the tablets should not be taken at night during work, but in the day-time. The temporary intake of tablets during shift-work as well as possible side-effects and corresponding behaviour patterns when disturbances of good health are appearing are to be discussed in detail particularly with the three-shift workers.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[Prevalence, degree of recognition and detection of hypertension and the quality of blood pressure control at the Wismut industrial branch].

On account of the active and passive selection conditioned by demands of fitness the prevalence of hypertension is 8.0% in the branch of industry Wismut. It shows a clear increase in the 4th decennium, in these cases there is a higher prevalence of hypertension in males younger than 40 years than in females of the same age, after the 40th year of age the relation inverts itself. The mild hypertension prevails (degree of severity I of hypertension according to WHO) with 87.8%. By a representative chance control in a proportion of 5,150 employees the determination of the degree of knowledge of hypertensive patients was nearly 100% and the degree of recognition in the dispensary of the works medical officer was 64.2%. The quality of the control of high blood pressure was investigated according to the random principle in 1,714 workers with hypertension. 36.6% of the patients with hypertension had values of blood pressure lower than 160/95 Hg, in 40.5% the blood pressure values were systolically in the region from 160 to 180 mm Hg and/or diastolically 95 to 105 mm Hg, in 22.9% systolically more than 180 mm Hg and diastolically more than 105 mm Hg, respectively. Forms of therapy, cardiovascular risk factors and influences of the working environment were by means of the factor analysis and the discrimination analysis investigated as to their influence on the quality of the control of high blood pressure and adequate conclusions were drawn.

Adult↗
PubMed1989

[Incidence of hypertension and borderline hypertension with reference to complex professional stress in above ground and under ground workers in ore mining].

Comprehensive health care for working people requires a deeper insight into the relationship between work load and biological reactions. This is necessary to be able to adequately influence the field of industrial medicine. The incidence of both hypertension and borderline-hypertension in a group of 200 face workers with complex work load as well as 150 pithead metal workers aged between 25 and 45 was measured over a period of 5 years (1981-1986). The hypertension incidence was 0.90% in the group of face workers and 1.46% with the pithead metal workers, while the incidence of borderline-hypertension was 1.30% for the face workers and 2.12% for the pithead metal workers. A statistically significant difference between those people working above ground and those working underground was not apparent. No relationship was found between age, Broca-index, habit of smoking, shift work, the total time away from home and the development of an increase in blood pressure. Both a hypertension incidence totalling 1.14% and an incidence of borderline-hypertension of 1.66% were found in the test group aged between 25 and 45. This roughly corresponded to the nationally statistical level and was in line with the relevant literature. There was no discernable effect with regard to developing hypertension and borderline-hypertension, respectively, as a result of complex work load in the test group. The incidence rates require regular blood pressure tests on normotensive miners and pithead workers, respectively, as a prerequisite for early detection and registering as well as an adequate therapy of both hypertension and borderline-hypertension.

Adult↗
PubMed1989

[Behavior of blood pressure in 3 shift work of workers with level I WHO hypertension].

Blood pressure tests were carried out on 40 shift workers with a hypertension level of 1 (according to WHO). Every 5 day period these tests were carried out before, during and after work in the early, late and night shifts. No significant change of both the systolic and the diastolic blood pressure could be found, which could result from shift work, before and after each shift irrespective of the blood pressure stabilization (good, satisfactory, unsatisfactory). The group containing satisfactorily as well as unsatisfactorily stabilized workers suffering from hypertension showed a significant decrease of the systolic blood pressure from the early shift through the late till the night shifts, with the diastolic blood pressure remaining constant. There were no apparent differences in the range of average blood pressure values regarding the various forms of treatment (without medication, monotherapy and combined therapy). The systolic blood pressure is significantly lower only in the group with no medication in the early shift after finishing work and it also decreases from the early shift through the late till the night shifts, while within the other therapy groups no change of both the systolic and the diastolic blood pressure was apparent. Thus shift work does not cause any measurable increase in blood pressure within the test group (suffering from hypertension) that would impair their working capacity. There is no increase of health risk with regard to the blood pressure response during shift work particularly during night work provided the blood pressure is within the normal range.

Adult↗
PubMed1989

[Individual physical performance capacity with physiological and biochemical indicators of stress].

22 health male subjects were exposed by a combination of physical exercises and heat. Strain related physiological and biochemical parameters were measured. Different individual reactions were obtained under controlled conditions. In dependence on the individual performance an increased mobilisation of lactat, free fatty acids and catecholamines were found. The determination of aerob physical performance can be applied for the evaluation of working capacity.

Adult↗
PubMed1989

[The content of Hb in blood and proteins, Fe, Fe-binding capacity, Cu and Zn in the blood plasma of sows and their piglets at the time of birth, after the uptake of colostrum and with different Fe supply].

Keeping of piglets on slatted metal floor, without complementary iron supply, caused anaemia within seven days from parturition. Hb levels in the blood dropped from 7.00 +/- 1.16 to 3.47 +/- 0.74 mmol/l. Iron deficit reduced growth and vitality. The iron levels in blood plasma of the piglets tested varied between 5 and 35 mumol/l, immediately after parturition. Intraperitoneal or oral administration of Fe-dextran (150 mg Fe) on the first day after parturition resulted in physiological iron levels in blood plasma, after seven days. Yet, when 14 days had passed, the levels were similar to those recorded from piglets without additional iron supply. Iron bonding capacity of blood plasma increased in piglets of all groups up to the seventh day from birth. Death occurred, on the second day of age, to many piglets with protein levels below 50 g/l plasma. Copper levels in blood plasma of newborn piglets were below those recordable from sows, but they went up by more than three times of their original values up to the seventh day from birth. In piglets, zinc, levels of blood plasma after parturition were higher than those of sows and went up by some 50 percent, within seven days from birth.

Animals↗