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41.
Gross cystic breast disease (GCBD) is one of the most common breast diseases, and women with apocrine (type I) cysts are at
higher risk of developing breast cancer than women with flattened (type II) cysts. Type I cysts contain fluid with an electrolyte
composition similar to that of intracellular fluid (Na/K ratio <3), whereas type II cysts fluid’s content resembles that of
plasma (Na/K ratio >3). The electrolyte composition of breast cyst fluid (BCF) has been investigated intensively; however,
there have been only a few studies in literature reporting the content of trace elements in BCF. The aim of this study was
to compare the concentrations of Na, K, Ca, P, Zn, Cu, Fe, and Na/K and trace element ratios in breast cyst fluid in two subgroups
of breast cysts. Sixty-three BCF were obtained by needle aspiration from premenopausal women with GCBD diagnosed by clinical,
xheromammographic, and cytological studies. After separation of cells for cytological evaluation, the cyst fluid was centrifuged
and supernatant stored at −80°C until the analysis. Sodium, potassium, calcium, phosphorus, and iron were measured using Roche
Diagnostics commercial kits on Hitachi 747-200 autoanalyzer. Measurements of copper and zinc were performed by flame atomic
absorption spectrophotometer on Shimadzu AAS 680. We found statistically significant higher K, lower Na, higher phosphorus
concentrations, and lower Na/K ratios in type I cysts when compared with type II cysts’ values. Median values of Na/K ratio
in type I and in type II were 0.32 and 6.2, respectively. Higher Zn, Cu, and Fe concentrations with respect to median values
were noted in type I cysts; higher [Na.Cu/K.Zn], [Na.Cu/K.Fe], and [Na.Zn/K.Fe] ratios were found in type II cysts. A significant
negative correlation existed between Na/K and Cu, and a significant positive correlation between Na/K and Fe in type II cysts
(r = −0.660, p = 0.007; r = 0.615, p = 0.014, respectively). We can conclude that the trace elements content of BCF, in addition to electrolytes, could be useful
in classifying the breast cyst. Future studies in larger series are needed to confirm these data. 相似文献
42.
Blood pressure values in Macaca fascicularis 总被引:1,自引:0,他引:1
Normal data are presented for blood pressure values of adult Macaca fascicularis. The mean arterial pressure (direct) was 99 +/- 9.8 mmHg (mean +/- standard deviation) and was not correlated with sex, age, or weight. Normative data are presented that suggest that this species has a range of values similar to that observed in other primate species including man. 相似文献
43.
Yan G. Zorbas Youri F. Federenko Konstantin A. Naexu 《Biological trace element research》1996,54(3):251-271
The objective of this investigation was to determine fluid electrolyte changes after water-loading tests and during hypokinesia
(decreased number of km taken per day) and daily intake of fluid and salt supplementation (FSS). The studies during hypokinesia
(HK) were performed for 364 d on 30 endurance-trained male volunteers in the age range of 23–26 yr, with an average peak oxygen
uptake, POU, of 64 mL/kg/min. All volunteers were divided into three equal groups: 10 volunteers were placed on a continuous
regime of exercise of 14.4 km/d and served as control subjects (CS); 10 volunteers were submitted to continuous HK without
FSS and were considered as the unsupplemented hypokinetic subjects (UHS); and 10 volunteers were under continuous HK and FSS
and were considered as the supplemented hypokinetic subjects (SHS). For the simulation of the hypokinetic effect, the UHS
and SHS groups were kept continuously under an average of 2.7 km/d for the duration of the study. Prior to exposure to HK,
the two groups of volunteers were on the same exercise regime as the control group. During a 60-d preexperimental period and
during the remainder of the study, water-loading tests with a water load of 20 mL/kg body wt/min were performed, and urinary
and plasma electrolytes (sodium, potassium, calcium, and magnesium) were measured. In the SHS group, urinary excretion of
electrolytes and plasma electrolyte content decreased, while in the UHS these values increased after water loading tests and
during HK. Based on the obtained data, it is concluded that chronic hyperhydration may be used to prevent or minimize urinary
and plasma electrolyte changes in endurance-trained volunteers after water-loading tests and during prolonged restriction
of muscular activity. 相似文献
44.
Abstract: The Na+ and K+ concentrations in isolated Torpedo marmorata synaptosomes were determined. Synaptosomes made according to the method of Israël et al. have high internal Na+ (290 MM) and low internal K+ (30 mM) concentrations. Modification of the homogenisation media permitted the isolation of synaptosomes which could maintain transmembrane ion gradients (internal Na+ , 96 mM; K+ , 81 mM); 0.1 mM-ouabain abolished these gradients. The trans-membrane Na+ gradient started to dissipate after 15 min at 20°C. Inclusion of ATP in the homogenisation medium enabled the synaptosomes to maintain the Na+ gradient for about 90 min. The presence of these transmembrane ion gradients stimulated choline uptake sevenfold. It is concluded that (a) by selecting the isolation media, Torpedo synaptosomes can be prepared with transmembrane ion gradients; (b) these gradients are ouabain-sensitive and stimulate choline uptake: (c) the synaptosomes require additional ATP to maintain the ion gradients. 相似文献
45.
Summary The rabbit colon displays a diversity of form and function along its proximo-distal axis. Morphologically, four regions can be discerned based on macroscopic and microscopic criteria: 1) the initial portion of the colon immediately distal to the cecum (P1), in which wart-like protrusions characterize the surface topography, is 10cm in length and endowed with three teniae. 2) The adjoining portion of the colon (P2) possesses one tenia, is about 20cm in length and also displays the wart-like protrusions in slightly less prominent form. 3) Fusus coli, a short segment approximately 4 cm in length, is free of teniae, but exhibits longitudinal folds on its inner aspect. Electron microscopically, it shows a paucity of microvilli in direct contrast to the two afore-mentioned regions. These three portions together constitute the proximal colon. 4) The fourth region of the colon, the distal colon, reaches a length of 80–100cm and shows no obvious second-order enlargements of its surface, displaying scanning electron microscopically ridges in looped configurations. Physiological parameters also showed differences depending on the region of the colon observed. Water content of the ingesta increases slightly during passage of the proximal colon, decreasing in the fusus coli and distal colon. Na concentration was highest in the area P1–P2, decreasing distally. K was low in area P2 and then rose toward the fusus, only to fall again distally. Nitrogen values decrease considerably during passage of P2 but only slightly distally. Transmural electrical potential differences also exhibit a characteristic, discontinuous gradient. 相似文献
46.
D. G. Butler M. Z. Alia Cadinouche 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1995,165(5):348-358
Renal function was observed in freshwater North American eels (Anguilla rostrata LeSueur) 2 weeks after the removal of the corpuscles of Stannius. There was a positive linear correlation between glomerular filtration rates and urine flow rates in both sham-operated and stanniectomized eels but there was no difference in slope or elevation between the two groups nor did urine flow rates ever exceed glomerular filtration rates. Osmolar clearance and free-water clearance were unchanged following stanniectomy. Plasma Ca2+ and K+ concentrations increased and plasma Mg2+, phosphate, Na+ and Cl- concentrations decreased following stanniectomy. Plasma ultrafilterable Ca increased and ultrafilterable Mg decreased after stanniectomy but neither changed relative to its total plasma concentration. Stanniectomy was followed by a decreased renal tubular reabsorption of Mg2+ relative to the amount filtered (C
Mg/C
In); the same applies to C
Na/C
In. Even though the filtered load of Ca increased in conjuction with the predictable hypercalcemia, there was no change in the fraction of filtered Ca reabsorbed. Net tubular secretion of phosphate was observed in both sham-operated and stanniectomized cels together with a slight increase in C
phos/C
In following stanniectomy. Some or all of these changes in plasma electrolytes and/or the modified renal transport of Na+, Mg2+ and possibly phosphate may be caused by the changes in cardiovascular function that were recently shown to follow stanniectomy.Abbreviations
CSX
Stanniectomized/stanniectomy
-
ER
endoplasmatic reticulum
-
FW
fresh water
-
GFR
glomerular filtration rate
-
Pi
inorganic phosphate
-
RAS
renin-angiotensin system
-
SHM
sham-operated
-
SW
sea water
-
UFR
urine flow rate
-
U/P ratio
urine/plasma ratio 相似文献