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1.
Summary Concentration of N, P, K, Ca, Mg and S in summer groundnut crop was higher than in kharif while Zn, Fe, Mn and Cu contents were higher in summer crop. Kernel's N, P and Zn; Leaflet's Ca and Mn; Stem's K and Fe; Root's S and Cu and Petiole's Mg contents were highest. Shell's N, P, K, Mg, S, Zn and Cu; Kernel's Ca, Fe and Mn contents were the least. N, P, K, S, Zn and Cu concentrations decreased linearly as the crop grew. Ca, Mg, Fe and Mn concentrations did not display any distinct pattern. Ca concentration was positively correlated with pod yield in both the seasons.  相似文献   

2.
选用5只年龄为3~4岁的波尔山羊公羊研究在稀释液中添加海藻糖对山羊精子功能和膜完整性的影响。山羊精子分别用含6.6 mmol/L、13.2 mmol/L、19.8 mmol/L、26.4 mmol/L、39.6 mmol/L、52.9 mmol/L、66.1mmol/L、79.3 mmol/L的不同海藻糖的Tris-柠檬酸-葡糖糖(TCG)稀释液(卵黄:18%;甘油:6%)稀释和冷冻。结果表明:39.6 mmol/L、52.9 mmol/L、66.1 mmol/L、79.3 mmol/L组降温后的精子活率显著(P<0.05)降低;52.9 mmol/L、66.1 mmol/L、79.3 mmol/L组降温后的精子畸形率和39.6 mmol/L组降温后的膨胀精子率显著(P<0.05)提高。26.4 mmol/L组和39.6 mmol/L组冻融后的精子活率显著(P<0.05)高于对照组;66.1mmol/L和79.3 mmol/L组冻融后的精子活率、畸形率分别显著(P<0.05)低于和高于对照组。19.8 mmol/L、26.4 mmol/L、39.6 mmol/L组冻融后精子获能率显著(P<0.05)低于对照组。39.6 mmol/L组冻融后顶体完整率和膨胀精子率显著(P<0.05)高于对照组,而66.1 mmol/L组和79.3 mmol/L组显著(P<0.05)低于对照组。39.6 mmol/L组的受胎率显著(P<0.05)高于对照组,而66.1mmol/L组和79.3 mmol/L组的受胎率显著(P<0.05)低于对照组。结果表明,在含18%的卵黄(v/v)、6%甘油(v/v)的TCG稀释液中,添加适宜浓度(26.4mmol/L和39.6 mmol/L)海藻糖,可显著提高山羊精子功能和膜的完整性。  相似文献   

3.
An experiment was conducted to invest effects of chronic cadmium poisoning on Zn, Cu, Fe, Ca, and metallothionein gene expression and protein synthesis in liver and kidney in rats. Forty rats, 6?weeks old, were randomly allocated into two groups. A group was given CdCl(2) (1?mg/KgCd(2+)) by intraperitoneal injection once a day. The other group was treated with normal saline in the same way. Liver and kidney were collected for analysis at the end of the third week. Results showed that Cd exposure increased Cd (P?相似文献   

4.
The complex structure of the human spermatozoa membrane comprises five topographic domains. Transmembrane asymmetry of the distribution of phospholipids including phosphatidylserine (PS) is considered a marker of cell activity. The objective of the study was to determine which cytomembrane domains of human spermatozoa are involved in PS membrane translocation and to identify the possible relationship of PS translocation with spermatozoa morphology and vitality. In normozoospermic semen of 35 donors, annexin-V labeling with fluorescein determined PS translocation. Propidium iodide staining distinguished between vital and dead spermatozoa. Three types of PS membrane translocation have been distinguished: (1) in the midpiece, (2) in the acrosomal part and (3) simultaneously in the midpiece and acrosomal part. In morphologically normal vital spermatozoa, PS translocation occurred in the midpiece but never in the equatorial region. In dead spermatozoa, simultaneous PS translocation in the midpiece and acrosomal part was most often observed. The difference between proportions of, respectively, vital and dead spermatozoa presenting PS translocation located in different domains was significant (P < 0.0001). In vital cells, there was no difference in PS translocation prevalence between morphologically normal and abnormal spermatozoa (P > 0.05). The strict relation of PS translocation to specific membrane domains indicates functional specificity. It seems doubtful to include this phenomenon in physiological mechanisms of elimination of abnormal spermatozoa.  相似文献   

5.
Mineral imbalance in the body may significantly contribute to the development and course of hypertension. In this paper, blood pressure figures have been linked to the levels of Fe, Ca, Mg, Zn, Cu, Na and K in hair. The research sample was composed of young men (n?=?91) aged 13–21, from the town of Mafinga, Iringa District, Tanzania. The data collected included their age, tribal background and weekly diet. Based on body mass index, the participants were categorised into pre-defined subgroups. To examine how the minerals in question affect blood pressure, correlation analysis and multiple ridge regression analysis were performed. Analysis of ridge regression findings for the researched group (n?=?91) shows that the minerals under scrutiny account for systolic blood pressure variation in 13 % and in 15 % for diastolic blood pressure variation. After including two additional variables—calendar age and body mass index—in regression analysis, the ultimate coefficient of determination (R 2) changes for systolic blood pressure and remains the same for diastolic blood pressure (R 2?=?0.194 and R 2?=?0.156, respectively). Nutritional analysis shows that the students included in the study received insufficient calories per day (1,500–2,200 kcal). The group of students with abnormal blood pressure were not aware of their poor health. Research findings may result from progressive environmental changes and poor nutrition in terms of food quantity and quality, which had an impact on the subjects’ blood pressure. Hair analysis used to determine mineral content in the body may be an auxiliary tool in identifying the links between factors leading to the development of hypertension.  相似文献   

6.
7.
The effect of phytate reduction, fat extraction, and addition of Ca in the form of skim or whole milk on Ca and Zn bioavailability from a breakfast containing bran muffins was studied in vitro and in vivo. Ca and Zn solubility were measured after in vitro simulated peptic and pancreatic digestion under pH conditions resembling those in the human GI tract. Absorption of Ca and Zn was measured in rats fed test meals tagged with 45Ca and 65Zn. Radioactivity in the femur and liver relative to levels found in rats injected with the isotopes served as criteria for 45Ca and 65Zn absorption, respectively. In vitro solubility was significantly depressed by the presence of phytate and inversely correlated with the phytate:Zn and the (phytate)(Ca):(Zn) ratios. Ca solubility was enhanced by extraction of fat and markedly increased by reduction in both fat and phytate. None of these effects was seen in vivo. However, 65Zn absorption was significantly decreased by fat extraction and phytate reduction although this treatment increased in vitro Zn solubility. Possible reasons for these discrepancies are discussed.  相似文献   

8.
In a mature mixed subalpine stand ofTsuga mertensiana andAbies amabilis, significantly higher Al levels were found in foliage, branch and root tissues ofT. mertensiana.Tsuga mertensiana had significant increases in Al, Ca and Mn levels with increasing foliage age. In current foliage,T. mertensiana had lower levels of Ca, similar levels of Mg and P, and higher levels of Mn thanA. amabilis. Both tree species had Cu and Fe present at higher levels in branch than foliage tissues. Fine roots had the highest concentrations of Al, Fe and Cu but the lowest Ca and Mn concentrations of all tissues analyzed. In the roots of both species, phloem tissues always had significantly higher Al levels than xylem. Fine roots (< 1 and 1–2 mm) ofT. mertensiana had higher Al levels than were found inA. amabilis. Roots greater than 2 mm in diameter exhibited no significant differences in Al levels in phloem or xylem tissue betweenA. amabilis andT. mertensiana. The two species show a clear difference in their ability to accumulate specific elements from the soil.  相似文献   

9.
An analysis of all known human herpesviruses has not previously been reported on sperm from normal donors. Using an array-based detection method, we determined the cross-sectional frequency of human herpesviruses in semen from 198 Danish sperm donors. Fifty-five of the donors had at least one ejaculate that was positive for one or more human herpesvirus. Of these 27.3% (n = 15) had a double herpesvirus infection. If corrected for the presence of multiple ejaculates from some donors, the adjusted frequency of herpesviruses in semen was 27.2% with HSV-1 in 0.4%; HSV-2 in 0.1%; EBV in 6.3%; HCMV in 2.7%; HHV-6A/B in 13.5%; HHV-7 in 4.2%, whereas none of the samples had detectable VZV or HHV-8. Subsequently, we examined longitudinally data on ejaculates from 11 herpesvirus-positive donors. Serial analyses revealed that a donor who tested positive for herpesvirus at one time point did not necessarily remain positive over time. For the most frequently found herpesvirus, HHV-6A/B, we examined its association with sperm. For HHV-6A/B PCR-positive semen samples, HHV-6A/B could be detected on the sperm by flow cytometry. Conversely, PCR-negative semen samples were negative by flow cytometry. HHV-6B was shown to associate with sperm within minutes in a concentration dependent manner. Confocal microscopy demonstrated that HHV-6B associated with the sperm head, but only to sperm with an intact acrosome. Taken together, our data suggest that HHV-6A/B could be transported to the uterus via binding to the sperm acrosome. Moreover, we find a 10 times higher frequency of HHV-7 in semen from healthy individuals than previously detected. Further research is required to determine the potential risk of using herpesvirus-positive donor semen. Longitudinally analyses of ejaculate series indicate that implementation of quarantine for a donor shown to shed a herpesvirus is not a tenable solution.  相似文献   

10.
In previous studies based on indirect procedures, we reported that Mg deficit increased the bioavailability of a number of elements such as calcium, zinc, iron, copper, manganese and decreased selenium absorption. The present study was designed to verify these findings by direct methods. We investigated the effect of dietary magnesium deficiency on enterocyte Ca, Fe, Zn, Cu, Mn and Se concentrations. Male Wistar rats were fed a Mg-deficient diet (129 mg Mg/kg food) for 70 days. Whole enterocytes from the upper jejunum were isolated and Ca, Fe, Zn, Cu, Mn and Se were determined. The results were compared with findings in a control group that was pair-fed with an identical diet except that it covered this species's nutritional requirements for Mg (480 mg Mg/kg food). The Mg-deficient diet significantly increased enterocyte content of Ca, Fe, Zn, Cu and Mn; however, we found no significant changes in the Se content of these cells. These data support the results obtained by indirect methods.  相似文献   

11.
This study was undertaken to determine the prevalence of Chlamydia trachomatis, Mycoplasmas, and Ureaplasmas in semen samples of the male partners of infertile couples and to investigate whether Chlamydia trachomatis could initiate apoptosis in human spermatozoa. A total of 85 males partners of infertile couples undergoing routine semen analysis according to World Health Organization guidelines were included. Specimens were examined for the presence of Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma hominis, Mycoplasma genitalium, Ureaplasma urealyticum and Ureaplasma parvum by Real time PCR (qPCR). Semen specimens were analysed for the appearance of apoptotic markers (sperm DNA fragmentation, activated caspase 3 levels, mitochondrial membrane potential (ΔΨm)) using flow cytometry. C. trachomatis, N. gonorrhoeae, U. urealyticum, M genitalium were detected in semen samples of 13 (15.2%), 5 (5.8%), 5 (5.8%) and 3 (3.5%) male partners of infertile couples, respectively. M. hominis and U. parvum were detected in semen sample of only one patient (1.1%). The semen of infertile men positive for C. trachomatis showed lower mean of semen count and lower rapid progressive motility (category [a]) of spermatozoa compared to uninfected men with statistically significances (p = 0.02 and p = 0.04, respectively). Flow cytometry analyses demonstrated a significant increase of the mean rate of semen with low ΔΨm and caspase 3 activation of infertile men positive for C. trachomatis compared to uninfected men (p = 0.006 and p = 0.001, respectively). DNA fragmentation was also increased in sperm of infertile men positive for C. trachomatis compared to uninfected men but without statistical significances (p = 0.62). Chlamydial infection was associated to loss of ΔΨm and caspase 3activation. Thus, C. trachomatis infection could be incriminated in apoptosis induction of spermatozoa. These effects may explain the negative direct impact of C. trachomatis infection on sperm fertilizing ability.  相似文献   

12.
Elemental concentrations of above- and belowground tissues were determined in anAbies amabilis stand in the Cascade Mountains, Washington, USA. These data were used to calculate the pools and circulation of trace elements and micronutrients on a stand level. For all elements except Al, a greater proportion (from 62 to 87%) was distributed in above- rather than belowground tissues. This contrasted sharply with the biocirculation of elements where 97% of the Al and Fe, 88% of the Cu and 67–84% of the Ca, P, and Mg of total detrital cycling was from the belowground components. Aboveground tissues, however, contributed 69% of the Zn, 65% of the K and 68% of the Mn found in annual detritus production. The proportion of total element pool circulated annually was the highest for Al (82%) and Fe (32%) followed by 13% and less for the remaining elements. Copper, Fe and Al were accumulated in root tissues, while Mn and Zn accumulated in foliage.We hypothesize that roots are an effective mechanism for avoiding Al toxicity in these subalpine ecosystems. The large root biomasses of these stands allow for high Al levels to be taken up and immobilized in roots; this is observed in the significantly higher Al accumulations in below- than aboveground tissues. The high root turnover in these stands is hypothesized to be a result of root senescence occurring in response to high Al accumulation. Furthermore, Al inputs into detritus production occur by soil horizon so that roots with high Al concentrations located in the Bhs horizon turnover and are retained within that horizon. These roots also decompose very slowly (99% decay = 456 years) due to the high Al and low Ca, Mn and Mg present in these tissues and therefore have very little impact on short-term elemental cycling.  相似文献   

13.
根瘤菌对土壤铜、锌和镉形态分配的影响   总被引:13,自引:0,他引:13  
以湖南郴州红壤和河北巩义褐土为供试土壤。制备Cu、Zn、Cd污染土壤。接种大豆根瘤菌(Rhi-zobium fredii)HN01,用连续提取法浸提土壤中不同形态的重金属.结果表明。褐土接种根瘤菌后固相结合态Zn总量降低10%。专性吸附态、氧化锰结合态和有机结合态Zn减少达9%~26%.红壤中结合态Zn的总量变化不显著,但专性吸附态和氧化锰结合态Zn含量显著减少。交换态Zn含量显著增加.褐土中接种根瘤菌抑制了Cu向土壤溶液的释放,固相结合态Cu总量增加18%,可交换态、专性吸附态、氧化锰结合态和有机结合态的Cu增加20%~54%.接种根瘤菌对土壤中Cd的溶解没有明显的抑制或促进作用,但改变了红壤中各形态Cd的含量高低顺序.Cd污染红壤中可交换态和有机结合态Cd含量分别增加22%和11%,专性吸附态和氧化锰结合态Cd分别减少14%和29%.根瘤菌对不同类型重金属及不同土壤中重金属形态影响的差异主要与土壤pH降低有关.  相似文献   

14.
Acute toxicity tests were conducted to establish the response of Selenastrum capricornutum Printz to sublethal concentrations of As, Cr, Cu, Ni and Zn at a broad range of pH levels. Cultures were incubated for a period of seven days at pH 4 in standard algal assay media containing sublethal concentrations of metals. At this low pH, growth was depressed for all metals tested. The adjustment of pH to higher levels resulted in increased growth when cultures were treated with As, Cu, or Ni and incubated for an additional 7 days. Toxicity was least at the optimum pH range for growth of the alga.The observation that the toxicity of As, Cu, and Ni to S. capricornutum decreases markedly at pH values above 4.0 may be of ecological importance in the control of acid mine pollution. If a high percentage of algae show a similar response to decreasing toxicity with increasing pH, it clearly would be of value to adopt measures which control pH as well as the levels of metals present. It was suggested that algae with a broad pH growth range, such as S. capricornutum, could benefit from the addition of highly alkaline materials to waters where certain metals are present.  相似文献   

15.
The transport of calcium to the extracellular space carried out by plasma membrane Ca2+ pumps (PMCAs) is essential for maintaining low Ca2+ concentrations in the cytosol of eukaryotic cells. The activity of PMCAs is controlled by autoinhibition. Autoinhibition is relieved by the binding of Ca2+-calmodulin to the calmodulin-binding autoinhibitory sequence, which in the human PMCA is located in the C-terminal segment and results in a PMCA of high maximal velocity of transport and high affinity for Ca2+. Autoinhibition involves the intramolecular interaction between the autoinhibitory domain and a not well defined region of the molecule near the catalytic site. Here we show that the fusion of GFP to the C terminus of the h4xb PMCA causes partial loss of autoinhibition by specifically increasing the Vmax. Mutation of residue Glu99 to Lys in the cytosolic portion of the M1 transmembrane helix at the other end of the molecule brought the Vmax of the h4xb PMCA to near that of the calmodulin-activated enzyme without increasing the apparent affinity for Ca2+. Altogether, the results suggest that the autoinhibitory interaction of the extreme C-terminal segment of the h4 PMCA is disturbed by changes of negatively charged residues of the N-terminal region. This would be consistent with a recently proposed model of an autoinhibited form of the plant ACA8 pump, although some differences are noted.  相似文献   

16.
Zn, Mg, Cu, Ca and Fe were determined spectrophotometrically in liver, kidneys, muscle, spleen and blood of Bufo regularis after a single i.m. injection of 6.2 mg Cd/kg (which represents the 96 hr LD50) alone or in combination with 40 mg EDTA/kg (the minimal EDTA concentration causing 100% survival over that period). Cadmium administration caused recognizable effects on the essential metals levels in different tissues and organs. In the majority of the tissues and organs studied, zinc and copper concentrations returned to their normal ranges in animals that received both cadmium and EDTA. In contrast, magnesium, calcium and iron contents not only returned back to their control values but also exceeded them.  相似文献   

17.
One hundred and eighteen algal isolates comprising seven classes were obtained from a range of sites from polluted rivers running through Cu or Zn mining regions, and from unpolluted rivers. All the isolates were tested for photosynthetic activity when exposed to Cu, Cd or Zn. The tolerance levels of Bacillariophyceae, Charophyceae, Cyanophyceae and Chlorophyceae to Cu showed significant positive correlations with Cu concentrations in the field. However the distribution of metal sensitivities of the algae from the sites with the same metal concentration was broad. Both Bacillariophyceae and Charophyceae had a number of strains whose sensitivity to Cu differed more widely in relation to Cu levels in the environment than Cyanophyceae and Chlorophyceae. Cyanophyceae were sensitive to all three metals, whether or not isolates were obtained from polluted sites, whereas Chlorophyceae tended to have high tolerance even in isolates from unpolluted sites. For Cd and Zn the correlation between tolerance levels and concentrations in the field was not so clear as for Cu. The occurrence of Cu tolerance was shown in 4 diatom species and one Charophyceae, whereas metal resistance occurred in some Chlorophyceae. Cu-tolerant isolates tended also to be Zn-tolerant in Bacillariophyceae, and Cd-resistant isolates tended also to be Zn-resistant in Chlorophyceae.  相似文献   

18.
Cadmium was administered subcutaneously to male Wistar rats, 0.1 mL/rat in 0.9% saline 3 times a wk for 4 wk at 3 mg Cd/kg. Saline was administered to control animals in an equivalent manner, without Cd. After the end of the dosing period, the distribution and excretion of Cd, Cu, Ca, Zn, and Fe were observed in some organs and excreta for 35 d (1, 7, 14, 21, 28, and 35 d). Cadmium dosing caused significant disturbances in the metabolism of Zn, Cu, Fe, and Ca, especially during the recovery period. Growth in Cd-dosed animals did not accelerate, even after 5 wk of recovery. There was evidence of mobilization of some elements among organs. Accumulation of Cd occurred in liver, kidney, and spleen during dosing, and during the recovery period it was retained in kidney and testes (for 2 wk) and cleared steadily in liver and RBC (for 5 wk), but increased in spleen (first 3 wk). The pattern of Cd excretion was closely associated with the binding of Cd with metallothioneins in kidney and liver for the first 21 and 7 d, respectively. This was associated with the excretion of Cd-metallothioneins (Cd-MT) in urine from d 1 to 21 during recovery. Cadmium caused higher Ca accumulations in testes and liver, which were probably associated with the lesions observed in these organs. Significant increases of Cu (in kidney d 7) and Fe (in liver) were observed during recovery. Furthermore, significant reductions of Cu and Fe were found in plasma, spleen, and RBC (after 5 wk) and kidney, spleen, and testes (on d 7), and blood (after 5 wk).  相似文献   

19.
20.
In this case–control study, we aimed to evaluate the serum and seminal plasma levels of Selenium (Se), total antioxidant capacity (TAC), and Coenzyme Q10 (CoQ-10) and determine their relationship with sperm concentration, motility, and morphology in men with idiopathic infertility. A total of 59 subjects were enrolled in the study. Forty four patients were diagnosed with idiopathic male infertility and had abnormal sperm parameters, and 15 subjects had normal sperm parameters with proven fertility. Serum Se, semen Se, and semen TAC levels were significantly different in the fertile and infertile groups (p?<?0.01, p?<?0.001, and p?<?0.001, respectively). However, serum TAC, serum, and seminal plasma CoQ-10 levels did not differ between fertile and infertile groups. When the levels of the measured parameters were compared in serum and seminal plasma, serum levels of Se were found to be correlated positively with the semen levels in all subjects included into the study (N?=?59) (r?=?0.46, p?<?0.01). A relationship was found between neither serum and semen levels of TAC nor between serum and semen levels of CoQ-10. Correlations among measured serum and semen parameters with sperm parameters demonstrated that both the serum and semen levels of Se were correlated positively with spermatozoa concentration, motility, and morphology. Additionally, seminal plasma levels of TAC correlated positively with all these sperm parameters. On the other hand, seminal plasma levels of CoQ-10 correlated only with sperm morphology but not with concentration or motility. No relationship was observed between serum levels of TAC or serum levels of CoQ-10 and sperm parameters. In conclusion, serum and seminal plasma Se deficiency may be a prominent determinant of abnormal sperm parameters and idiopathic male infertility. Measurement of serum Se levels may help determine nutritional status and antioxidant capacity in infertile patients, which may help distinguish those patients who will benefit from supplementation therapy.  相似文献   

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