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811.
Anwar A. Abdullah Michael M. Yeoman John Grace 《Plant Cell, Tissue and Organ Culture》1985,5(1):35-44
Adventitious buds were induced when isolated whole embryos, and excised cotyledons from treated seeds of Calabrian pine (Pinus brutia Ten.) were cultured on a cytokinin-supplemented medium. The adventitious buds formed directly from the cotyledons. The highest number of bud primordia were formed, with both embryos and excised cotyledons, after 6 weeks on a BAP — supplemented Schenk and Hildebrandt medium under a 16 h photoperiod. The buds, when separated and maintained individually on a full-strength medium without growth regulators, developed into well-formed shoots within 4 weeks. The average number of harvested shoots obtained (>1 cm in height) per seed over 24 weeks was 55; however, a maximum number of 152 shoots was obtained from one individual over the same period. The shoot forming capacity of the meristematic tissue was not lost after seven harvests. 相似文献
812.
The breeding cycle of an air-breathing Anabantid, Trichogaster pectoralis was studied in Malaysia. The species was found to breed all the year but with pronounced peaks of activity associated with the two wetter periods in the year. The advantages of this timing and the cues which stimulate gonadal activity are discussed. From the study of oocyte distribution in selected ovaries it was concluded that T. pectoralis is a total spawner although a batch of ripe oocytes may be released over an extended period of time. Fecundity was found to be related to length of fish by the formula (log10 Egg no.)=–4.6854+4.3080 log10 standard length (S.L.) (mm). 相似文献
813.
Böyük A Banlı O Gümüş M Evliyaoğlu O Demirelli S 《Biological trace element research》2011,143(3):1282-1288
Laparoscopic adjustable gastric banding (LAGB) causes significant weight loss in morbidly obese adults. However, its consequences
on nutritional status still remain unclear. There are a few studies determining the nutritional status after LAGB and none
have focused on the serum levels of zinc (Zn), copper (Cu), and ceruloplasmin (CP). We aimed to investigate the effects of
LAGB surgery on plasma Zn, Cu, and CP levels. Thirty patients with LAGB with morbid obesity were included. Blood samples were
collected preooperatively and in the postoperative third month to determine plasma Zn, Cu, and CP levels. The mean preoperative
and postoperative body mass indexes (BMI) were 44.9 ± 7.4 kg/m2 and 44.1 ± 6.5 kg/m2, respectively. The mean weight loss was 12.9 ± 3.3 kg at the postoperative third month. The postoperative Zn (500 ± 130 ng/ml),
Cu (280 ± 80 ng/ml), and CP (23.9 ± 8.8 mg/dl) values were statistically significantly lower than the preooperative Zn (740 ± 230 ng/ml),
Cu (370 ± 80 ng/ml) and CP (33.3 ± 15.7 mg/dl) levels (p < 0.05). Decreases in the plasma levels of Zn, Cu, and CP were seen postoperatively following LAGB surgery. The nutritional
status of LAGB-applied patients should be monitored and mineral supplementation may be considered. 相似文献
814.
Özkaya D Naziroğlu M Armağan A Demirel A Köroglu BK Çolakoğlu N Kükner A Sönmez TT 《Cell biochemistry and function》2011,29(4):287-293
Diabetes induces oxidative stress in aged human and rat, although daily supplementation of vitamins C and E (VCE) can be beneficial to aged diabetic rats by reducing free radical production. The aim of the present study was to evaluate whether dietary VCE supplementation relieves oxidative stress in streptozotocin (STZ)-induced diabetic in aged rats. Thirty aged rats were randomly divided into three groups. The first group was used as a control. The second group was made diabetic using a single dose of intraperitoneal STZ. VCE-supplemented feed was given to aged diabetic rats constituting the third group. On the 21st day of the experiment, blood, lens and kidney samples were taken from all animals. Glutathione peroxidase (GSH-Px) activity in lens and kidney, reduced glutathione (GSH), vitamin E and β-carotene concentrations in kidney were lower in the diabetic group than in the control whereas plasma glucose, urea and creatinine, and kidney and lens peroxidation (LP) levels were higher in the diabetic group than in the control. However, kidney and lens LP levels, and plasma glucose, urea and creatinine values were decreased by VCE supplementation. Lens and kidney GSH-Px activity, kidney GSH, vitamin E and β-carotene concentrations and erythrocyte counts were increased by VCE treatment. Kidney weights, vitamin A, haemoglobin, hematocrit, leukocyte and platelets values were not changed by diabetes and/or VCE supplementation. VCE ameliorated also diabetes-induced histopathological changes in kidney. In conclusion, we observed that VCE supplementation is beneficial towards kidney and lens of aged diabetic rats by modulating oxidative and antioxidant systems. 相似文献
815.
816.
Gaafar A Sheereen A Iqneibi A Mohamed G Al Sulaiman A Turpeinen H Al Hussein K 《Molecular biology reports》2011,38(4):2603-2610
Killer cell immunoglobulin-like receptors (KIRs) influence the outcome of haematopoetic stem cell transplantation by modulating
the cytotoxic ability of natural killer (NK) cells and a subset of T cells. KIRs are also highly polymorphic and could therefore
be good population genetic markers, much like their human leukocyte antigen (HLA) ligands. This study represents the first
report on distribution of 16 KIR genes in 162 unrelated healthy Saudi individuals. All the 16 KIR genes were observed in the
studied population and the four framework genes (KIR2DL4, 3DL2, 3DL3 and 3DP1) were present in all individuals. Forty- one distinct KIR profiles were expressed in our population, 11 of which had not
been previously described in other populations including the Middle Eastern population. AA1, the most common genotypic profile
was observed at a frequency of 26.5%. The group A haplotype was more frequent (53%) in the Saudi population compared to the
group B haplotype (47%). The pattern of the inhibitory KIR/HLA ligands were also analyzed and 52.3% of the Saudi population
was found to express two pairs of the inhibitory KIR/HLA-C. The KIR gene frequencies suggests that the Saudi population shares
common general features with the Middle Eastern and other populations, but still has its own unique frequencies of several
KIR loci. 相似文献
817.
Gümüş M Yüksel H Evliyaoğlu O Kapan M Böyük A Önder A Aldemir M 《Biological trace element research》2011,143(1):386-393
Ellagic acid (EA) is a natural polyphenolic compound. Although, modulator effects of EA on copper (Cu) and zinc (Zn) levels
in some liver diseases have been reported in experimental animals, its effects in obstructive jaundice (OJ) has not been clarified.
We aimed to evaluate potential effects of EA on Cu and Zn levels in liver and serum of cholestatic rats. Forty Wistar albino
rats were equally divided into four groups. First group was used as controls. Second group received EA (60 mg−1 kg−1 day−1) for 8 days. Third was OJ group, and fourth group was OJ plus EA group. After 8 days, blood and liver samples were obtained.
Higher serum and liver Cu and lower serum and liver Zn levels were found in OJ group (p < 0.05) compared with other groups. However, these differences reached to significant levels for Cu in serum and for Zn in
lever. Higher serum copper levels were decreased, and lower liver Zn levels were increased by EA treatment in cholestatic
rats (p < 0.05). Also, higher Cu/Zn ratio in OJ group was decreased by EA treatment both in liver (p < 0.05) and in serum (p < 0.05). Significantly higher serum bilirubin, alkaline phosphatase, alanine aminotransferase, and aspartate aminotransferase
values were found in OJ and OJ + EA groups compared with the control and EA groups (p < 0.05). In conclusion, result of the current study indicated that ellagic acid has modulator effects on Cu and Zn levels
in liver and serum of cholestatic rats. 相似文献
818.
Tham YJ Latif PA Abdullah AM Shamala-Devi A Taufiq-Yap YH 《Bioresource technology》2011,102(2):724-728
In the effort to find alternative low cost adsorbent for volatile organic vapors has prompted this research in assessing the effectiveness of activated carbon produced from durian shell in removing toluene vapors. Durian shells were impregnated with different concentrations of H3PO4 followed by carbonization at 500 °C for 20 min under nitrogen atmosphere. The prepared durian shell activated carbon (DSAC) was characterized for its physical and chemical properties. The removal efficiency of toluene by DSAC was performed using different toluene concentrations. Results showed that the highest BET surface area of the produced DSAC was 1404 m2/g. Highest removal efficiency of toluene vapors was achieved by using DSAC impregnated with 30% of acid concentration heated at 500 °C for 20 min heating duration. However, there is insignificant difference between removal efficiency of toluene by DSAC and different toluene concentrations. The toluene adsorption by DSAC was better fitted into Freundlich model. 相似文献
819.
Fatema S. Alsubhi Abdullah M. Althunyan Christine G. Curtis Howard M. Clarke 《CMAJ》2011,183(12):1367-1370
Background:
Peripheral nerve palsies of the upper extremities presenting at birth can be distressing for families and care providers. It is therefore important to be able to identify patients whose diagnosis is compatible with full recovery so that their families can be reassured.Methods:
We conducted a retrospective review of all infants presenting with weakness of the upper extremity to our clinic between July 1995 and September 2009. We also conducted a review of the current literature.Results:
During the study period, 953 infants presented to our clinic. Of these patients, 25 were identified as having isolated radial nerve palsy (i.e., a radial nerve palsy in isolation with good shoulder function and intact flexion of the elbow). Seventeen infants (68.0%) had a subcutaneous nodule representing fat necrosis in the inferior posterolateral portion of the affected arm. Full recovery occurred in all patients within a range of one week to six months, and 72.0% of the patients (18/25) had fully recovered by the time they were two months old.Interpretation:
Although the outcome of obstetrical brachial plexus palsy is highly variable, isolated radial nerve palsy in the newborn carries a uniformly favourable prognosis.Peripheral nerve palsies in the newborn are uncommon and usually involve the brachial plexus or facial nerve.1 Isolated radial nerve palsy in the newborn is a rare phenomenon and may be misdiagnosed as obstetrical brachial plexus palsy. It is important to differentiate between these two conditions, as the management and prognosis of each diagnosis are different. Over the last three decades, multiple reports of small numbers of patients with radial nerve palsy present at birth have been published.2–6 This paper presents the largest single series of this lesion currently documented in the literature. 相似文献820.