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991.
To study the relationship between urine flow, urinary prostaglandin (PG) and kallikrein excretion in the rat high urine flow was induced in hydropenic Long-Evans rats by either hypotonic volume expansion or with manniitol or with furosemide. PGE, excretion remained unchanged during hypotonic volume expansion (134.5 ± 29.7 before and 153.0 ± 48.9 pg/min after) while it decreased significantly with mannitol (from 166.3 ± 32.4 to 45.2 ± 8.2 pg/min, p<0.01) and with furosemide (from 170.0 ± 20.4 to 29.5 ± 5.3 pg/min, p<0.001). PGF excretion rates were slightly reduced following all three interventions. Urinary kallikrein excretion remained unchanged in all three groups of animals. It is concluded that, in contrast to human and dogs in the rat urine flow and urinary PG excretion are not interlinked.  相似文献   
992.
The effect of amniotic fluid obtained from second trimester (16–20 wks) and term pregnancies (38–41 wks) on the production of PGE and F by human amnion, decidua and myometrium at term was determined using tissue slices incubated in vitro. Midpregnancy amniotic fluid neither inhibited nor stimulated the prostanoid production by any of the tissues. In contrast, term amniotic fluid obtained before as well as after the onset of labor markedly increased the production of both PGE and PGF in decidua and myometrium from levels in Krebs solution. The prostanoid production (PGE + PGF) in amnoin was not significantly increased but the proportion of PGF was raised during incubations in term amniotic fluid. In decidua and myometrium the increase in PGE and PGF production in term amniotic fluid was approximately 200 and 400 percent respectively, from control values in Krebs solution. We propose that the stimulatory activity in term amniotic fluid in responsible for the accelerated synthesis of prostaglandins after of membranes, which is reflected in raised PGF metabolite levels in maternal circulation. It may also be the reason for the rise in amniotic fluid prostaglandin levels around the 35th week of gestation, and perhaps for the onset of labor.  相似文献   
993.
The macrobenthic fauna associated withFucus at a station in the Kiel Fjord was investigated from June 1978 until June 1979. The predominant group in number as well as in biomass were gammarids. They formed, together with the isopodsIdotea spp., approximately 95 % of the total average annual biomass. The total dry weight of all macrobenthic animals (excl.Littorina spp.) increased from 1.9 g per kgFucus in May to about 16 g in June–August, and dropped to 8.3 g in September. Winter average dry weight values were only about 6 % of the summer values.  相似文献   
994.
A hypothesis of Gryglewski et al. explains the correlation between increased level of LDL and development of atherosclerosis by inhibition of PGI2 synthesis by increased peroxide content of LDL. The aim of the present paper was to examine this hypothesis. The major results are: 1) Preparation of LDL in the presence of .02 % butylated hydroxytoluene did not reduce the lipid peroxide content of LDL from men and women and not change the inhibition or stimulation of the in vitro biosynthesis of PGI2 by LDL isolated from blood of men or women, respectively. 2) In the LDL and HDL, respectively, of healthy men we found nearly the same lipid peroxide levels (nmole malondialdehyde (MDA)/mg lipoprotein-cholesterol) as in the lipoproteins of male patients with hyperlipidemia type IIa or IV, but the peroxide concentration is three times higher in HDL as in LDL. 3) LDL isolated from healthy men inhibited in dose dependent fashion the generation of PGI2 from PGH2 by aortic microsomes whereas LDL from premopausal women stimulated PGI2 formation even calculated as LDL lipid peroxides (in nM MDA/ml). The results call into question the hypothesis that diminished PGI2 formation by atherosclerotic vessels is related to inhibition of PGI2 synthetase by lipid peroxides present in LDL in the lesions. A new working hypothesis is presented that also the fatty acid pattern and the lipid class composition in the LDL are important for their influence on the PGI2 formation.  相似文献   
995.
Proteins excreted in urine due to renal failure were separated on Mono QTM, a new strong anion exchanger designed for fast high-resolution protein separations. The separation procedure was divided into two steps. The first step involved removal of low-molecular- weight substances by rapid desalting on a Sephadex G-25 Superfine column. In the second step, the total protein fraction (3–6 ml) was loaded onto the Mono Q column with the aid of a superloop. The proteins were adsorbed onto the top of the ion-exchanger column and gradually displaced by a combined pH and salt gradient in 40 min. The choice of ion exchanger and initial operating conditions were based on data obtained from electrophoretic titration curve experiments. Identification of separated proteins was achieved by fused rocket electrophoresis and sodium dodecyl sulphate-polyacrylamide gel electrophoresis, respectively.  相似文献   
996.
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999.
Plasma cholinesterase (pChE) levels and erythrocyte acetylcholinesterase (eAChE) levels were studied in 6 cows before, during and after parturition (Group I), their calves (Group II), 38 cows suffering from parturient paresis (Group III) and 14 newly delivered non-paretic cows (Group IV). The mean of the pChE level in Group I was 1.5 μkat/1 ± 0.20 before parturition and decreased significantly (P ≦ 0.05) to 1.2 ukat/1 ± 0.16 after parturition. The eAChE level was before parturition ≅ 140 ukat/1 and decreased to ≅ 130 μkat/1 4–5 weeks after parturition. At birth the pChE level was 12.8 ukat/1 ± 5.9 in Group II. After 4 weeks the level had decreased to 2.3 ukat/1 ±0.3. In the bull calves the pChE level started to increase when they were 6 weeks old and reached a level of 5.7 μkat/1 ± 0.6 before slaughter at 6 months of age. The heifers did not show this increase. They had a level of around 2 μkat/1 throughout the investigation. The eAChE level at birth was 119 μkat/1 and increased slowly to a level of 145 μkat/1 at 6 months. No differences between the sexes were found. The cows suffering from parturient paresis had a pChE level of 1.80 μkat/1 ± 0.30 before treatment with calcium (Ca). The level decreased significantly (P ≦ 0.001) after Ca-infusion to a level of 1.67 ukat/1 ±0.29. Group IV had a pChE level of 1.65 μkat/1 ± 0.42 at parturition. Two to 4 months later the cows that had recovered from milk fever had a level of 1.61 μkat/1 ± 0.31 and the control cows 1.66 ukat/1 ± 0.48. No differences between the groups were found for the eAChE level. The findings show that parturition influences the pChE level in cows and that sex influences the pChE level in calves between 6 weeks to at least 6 months of age. Furthermore the elevated pChE level found in the cows suffering from parturient paresis before Ca infusion may be a further sign of a disturbance in the cholinergic system with a special preference to the neuromuscular junctions.  相似文献   
1000.
Gas chromatography/mass spectrometry adapted for selected ion monitoring was used to detect C32 mycocerosic acid in short-term incubated cultures of procineand canine strains of mycobacteria. The method can be employed for rapid differentiation of Mycobacterium tuberculosis from M. avium-intracellulare.  相似文献   
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