摘要:

The portal blood velocity and flow were measured by means of pulsed echo-Doppler in 60 normal subjects of 4 different age groups (≤ 40, 41–55, 56–70, ≥ 71 years). All subjects had normal routine liver function tests and no history of liver disease. Portal blood velocity decreased from 15.7 ± 3.2 cm/s in younger subjects to 12.4 ± 1.7 in subjects over 71 years (ANOVA: p = 0.005). Similarly portal blood flow decreased (p = 0.025). Both portal blood velocity and flow were inversely correlated with age (r = ––0.583 and ––0.505, respectively). No changes in portal vein diameter were observed. The age-related decline in portal flow may account for the decrease in hepatic blood flow previously document

ISSN:0304-324X    

DOI:10.1159/000213000

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

The influence of acute treadmill exercise on natural killer (NK) cell tumor cytotoxicity in vitro was studied in elderly women after participation in a program of physical exercise training (PET) (n = 7) or after participation in a paralleling nonexercise control (NEC) condition (n = 7). The two study groups were equated (p > 0.05) according to age, percent total body fat, functional status as measured by multi-inventory ranking, and exercise capacity. After the experimental period, the PET subjects had a greater basal level of NK activity than the NEC subjects (PET 38.2 percent specific lysis, %SL, vs. NEC 28.8% SL; p < 0.05). Both groups experienced an increase in NK activity after acute treadmill exercise (PET 38.2–57.4% SL, p < 0.01; NEC 28.8–37.8% SL, p < 0.05), but the increase in the PET subjects was significantly (p < 0.05) grater than that observed in the NEC subjects. We conclude that natural cellular-mediated tumor cytotoxicity is increased in response to acute exercise and long-term PET in elderly wo

ISSN:0304-324X    

DOI:10.1159/000213001

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

Left ventricular function and hemodynamic alterations at rest were measured echocardiographically following running or isometric training in 40 healthy elderly. They were randomly assigned into two groups. Twenty (67 ± 4 years) were engaged in running and 20 (67.8 ± 3.8 years) in isometric training programs. All subjects underwent a 12-week program, 3 times a week 30 min each session. The running exercise (REX) group had an aerobic exercise conditioning program at 70% of their VO2max. The program for the isometric exercise (IEX) group included weight lifting utilizing large muscle mass at 30% of their maximal voluntary contraction. After training, the REX group increased significantly (p < 0.05) their VO2max from 2.08 ± 0.37 to 2.36 ± 0.41 liter/min and ejection fraction 56 ± 5.9 to 62 ± 6.1%. They decreased significantly their heart rate, from 73 ± 7 to 65 ± 7 beats/min. No change occurred in the IEX group in left ventricular function and hemodynamic parameters. These data suggest that left ventricular responses at rest differ between the two groups following a short-term training with a favorable response after REX training. In addition, this study demonstrated that a controlled aerobic training program is a better way to improve physical capacity than is a weight lifting program for trained healthy

ISSN:0304-324X    

DOI:10.1159/000213002

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

The present study was designed to examine the effect of chronic type 2 (noninsulin-dependent) diabetes mellitus on cerebral blood flow and metabolism during cerebral ischemia induced by bilateral carotid artery occlusion in spontaneously hypertensive rats. Diabetes was produced by streptozotocin treatment in 2-day neonates and the experiment was performed at the age of 5 months. The level of mean arterial pressure was not different between diabetic and nondiabetic rats. At 1 h after ischemia, cerebral blood flow was decreased to 1% of the resting value and supratentorial lactate was increased by 8-fold of control, being virtually the same in both groups of rats. In contrast, reduction of cerebral ATP was much less in diabetic rats (1.64 ± 0.15 mmol/kg) than in nondiabetic rats (0.74 ± 0.07 mmol/kg) (p < 0.001); ATP in nonischemic control is 2.80–2.85 mmol/kg. These results could not be explained by the difference in cerebral blood flow between the groups during ischemia. The results suggest that chronic mild hyperglycemia exerts rather a protective effect on the brain against ischemic insult. Effective utilization of metabolites, such as glucose and ketone bodies, may play an important role to minimize metabolic derangements in the ischemic brain in type 2 diabetic-hyperglycemic r

ISSN:0304-324X    

DOI:10.1159/000213003

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

The lens growth was studied in a number of curves representing 16 mammalian species. Emphasis was placed on determining the length of the lens development stage. All the lens curves studied went through a growth crisis: It is a period of apparent growth slowing down, lasting linear during the resting lifespan (adult stage). The growth crisis occurred at a length that was characteristic for the species and was shown to be directly correlated with the species maximum lifespan potential. These results may indicate the prevalence of a common functional basis regulating the lens growth and thus operating in the longevity of mammalian species.

ISSN:0304-324X    

DOI:10.1159/000213004

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

The glucose uptake of lizard brain slices decreased between young and middle-aged groups. There was a significant increase in the parameter between the middle-aged and old-age groups. Cold shock induced a decrease in glucose uptake of brain slices in the old, with no appreciable effect in the young and middle aged.

ISSN:0304-324X    

DOI:10.1159/000213005

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

Male C57BL/6J mice ranging in age from 50 to 1186 days were used to measure total calcium and calmodulin concentrations. The increase in calcium between 0 and 1,000 days of age was 260% for kidney, followed by brain (189%), heart (173.5%), lung (106.5%) and liver (78.5%). Calcium in femur declined by 28.2%. The calmodulin content of liver increased with ageing. Both liver and kidney calmodulin concentrations declined early in life followed by ageing-related increases. Brain, lung and heart calmodulin concentrations did not change significantly with ageing. We conclude that changes in calcium homeostasis are not reflected in calmodulin changes. The loss of calcium in bone is consistent with the occurrence of osteoporosis in ageing C57 mice.

ISSN:0304-324X    

DOI:10.1159/000213006

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

The effects of alpha- and beta-adrenergic receptors on the lower limits of cerebral (CBF) and cerebellar blood flow (CeBF) autoregulation were examined in spontaneously hypertensive rats. CBF and CeBF were measured during hemorrhagic hypotension in rats treated with adrenergic blockers, phenoxybenzamine (PBZ) or propranolol (PPL), using a hydrogen clearance method. The lower limits for CBF beyond which blood flow was decreased steeply were 72% of resting values in the control, 44 in the PBZ and 80 in the PPL group. Similar tendency was also observed for CeBF. In the control group, the reducing rates of mean arterial pressure (MAP) to decrease CBF by 15 and 30% of the resting values were 33 % (58 mm Hg) of the resting MAP and 46% (80 mm Hg), respectively, and those to reduce CeBF to the same extent were 35% (61 mm Hg) and 52% (92 mm Hg), respectively. In the PBZ group, the respective reducing rates of MAP were 52% (71 mm Hg) and 65% (88 mm Hg), respectively, for CBF and 50% (68 mm Hg) and 65% (88 mm Hg), respectively, for CeBF. In contrast, in the PPL group, those rates were 22% (39 mm Hg) and 32% (56 mm Hg), respectively, for CBF, and 23% (40 mm Hg) and 30% (52 mm Hg), respectively, for CeBF, being significantly smaller than those in the control and the PBZ groups (p < 0.01, respectively). These results indicate that the alpha-adrenoreceptor blockade induces a downward shift of the lower limits of CBF and CeBF autoregulation, and the beta-adrenoreceptor blockade causes upward shift of the lower limits. Inhibition of alpha-receptors may be favorable, whereas blockade of beta-receptors is rather detrimental for the maintenance of cerebral blood flow during hypotension in hypertensive and/or aged patients.

ISSN:0304-324X    

DOI:10.1159/000213007

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

It is often believed that the mortality intensity in the modern human population undergoes an exponential growth after 40 years, i.e. the actuarial aging rate is regarded to be constant after 40 years. To check this assumption we have calculated local aging rate values for 13 age ranges (within the interval of 30–92 years) for the male and female population of 48 states of the US (1969–1971). It was found that generally the male aging rate is not constant but lowers monotonically with time, while for females the aging rate has a pronounced ∼-shaped character with a minimum in the range of 45–60 years and a maximum within the range of 70–80 years. The results obtained are a warning to those who boldly use Gompertz or Gompertz-Makeham formulas when describing human aging on the populat

ISSN:0304-324X    

DOI:10.1159/000213008

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

Urinary tract infections (UTI) caused by organisms resistant to trimethoprim (TMP), as well as their faecal carriage were studied in two geriatric wards. TMP-resistant UTI was common (26 and 50% of admission and ward-acquired infections, respectively) and was associated with male sex, recurrent and transferred admissions and length of stay. There was a strong relationship between faecal carriage and isolation of TMP-resistant organisms from urine. Antimicrobial exposure was the major determinant of TMP-resistant faecal carriage.

ISSN:0304-324X    

DOI:10.1159/000213009

出版商:S. Karger AG    

年代:1989

数据来源: Karger