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51.

The use of plants in treatments has been as old as humanity and it has preserved its popularity for centuries til now because of their availability, affordability and safeness. However, despite their widespread use, safety and quality issues have been major concerns in the world due to industrial- and anthropogenic-based heavy metal contamination risks. Thus, this study was attempted to analyze the heavy metal levels and mineral nutrient status of widely used medicinal plants in Turkey to have insights about their health implications on humans. The plant concentrations of B, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb and Zn were analyzed by ICP-OES in the leaves of 44 medical plants purchased from herbal markets of three different districts of Istanbul/Turkey. The measured lowest to highest concentrations were 0.065–79.749 mg kg−1 B, 921.802–12,854.410 mg kg−1 Ca, 0.020–0.558 mg kg−1 Cd, 0.015–4.978 mg kg−1 Cr, 0.042–8.489 mg kg−1 Cu, 34.356–858.446 mg kg−1 Fe, 791.323–15,569.349 mg kg−1 K, 102.236–2837.836 mg kg−1 Mg, 4.915–91.519 mg kg−1 Mn, 10.224–3213.703 mg kg−1 Na, 0.001–5.589 mg kg−1 Ni, 0.003–3.636 mg kg−1 Pb and 2.601–36.102 mg kg−1 Zn. Those levels in plants were in acceptable limits though some elements in some plants have high limits which were not harmful. Variations (above acceptable limits) in element concentrations also indicated that these plants could be contaminated with other metals and that genetic variations may influence accumulation of these elements at different contents. Overall, analyzed medicinal plants are expected not to pose any serious threat to human health.

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52.
In this study, we demonstrated that sodium selenite with high doses (≥ 10-3 M) were potent in inducing a contracture type effect on heart and smooth muscles. Selenite (Se), at a concentration of 10-3 M, caused a contracture effect in heart preparations. Also, low Se concentrations did not have any significant effect. Although low concentrations of Se (≥ 10-5 M) had a biphasic effects on acetylcholine (ACh) induced and spontaneous ileum contractions, 10-3 M selenite enhanced once more a contracture effect similar to that of the heart preparations. Replacing Ca2+ concentration of the bathing solution by twofold Ca2+ or Ca2+-free did not change the effects of selenite (10-5 M) on contractility of ileum preparations. In vascular smooth muscle, low concentration of selenite (<10-4) had no significant effects on KC1, and phenylephrine-induced contractions and acethylcholineinduced endothelium-dependent relaxations of isolated rabbit aorta. However, the contractions induced by phenylephrine and the relaxations induced by acetylcholine in rabbit aorta were depressed significantly by high concentration of selenite (10-3 M). The results obtained by selenite exposure from these three different types of tissue preparations first suggest that the high concentration of selenite exposure induces some alterations in the functions of muscles and endothelium in a tissue and dose-dependent manner. Second, this observed irreversible type of dysfunction of tissues induced by l0-3 M selenite is not directly dependent on the Ca2+ entrance into the cytosol, but might be induced by the increase of intracellular Ca2+ with the disturbance of Ca2+ regulation.  相似文献   
53.
The present study was designed to investigate and compare the effects of dietary selenium (Se) and vitamin E on some physiological parameters and histological changes in liver, heart, and skin tissues, as well as the blood parameters and the related enzymes. Both sex young rabbits were fed with deficient (9.8 μg/kg diet), adequate (225 μg/kg diet), and rich (4.2 mg/kg diet) Se and vitamin E diets for 12–15 wk for this purpose. As the plasma Se levels and the erythrocyte glutathione (GSH) peroxidase activity decreased (79.8±9.4 ng/ml and 2.0±0.3 U/g Hb, respectively) in the deficient group, these values increased (100.4±2.7 ng/mL and 14.5±4.3 U/g Hb) in the rich group significantly with respect to the control group. The other antioxidant enzyme activities and the related element levels did not change significantly in either one of the experimental groups. Although the platelet counts of the two experimental groups were not different from the control values, the collagen and the adenosine diphosphate (ADP) stimulated platelet aggregation rate and intensity increased in the deficient group (p<0.05) and decreased very significantly (p<0.001) in the rich group. In both of the experimental groups, as the percentage values of the neutrophils decreased, the lymphocytes and the eosinophils increased significantly. According to the light microscopic investigations, the observed lesions of considerable intensity within the tissues that elicit cell degenerations were more pronounced in the animals fed with the rich diet than in those fed with the deficient diet. The deficiency as well as toxicity of Se and the deficiency of vitamin E caused several alterations in the physiological functions of the tissues, and these alterations were supported by the histological lesions within these tissues.  相似文献   
54.
55.
Forty-eight male lambs were used to evaluate the effect of dietary supplementation of mannanoligosaccharide (MOS) with or without parenteral Escherichia coli injection on their growth performance, feed conversion efficiency, blood metabolites, total serum immunoglobulin G (IgG) levels and antibody response. Lambs were randomly assigned to four groups of 12 animals each. In groups C (control) and CE (E. coli challenged), animals were fed commercial concentrate pellets and hay (50:50), and in groups M (MOS) and ME (MOS + E. coli challenged), animals were fed commercial concentrate pellets including MOS at 0.2% and hay (50:50). At day 15 and 30, animals in groups CE and ME were injected subcutaneously with 1 ml of phosphate buffered saline (PBS) suspension containing 10(6) cfu of heat inactivated non-toxigenic E. coli O157:H7, while animals in C and M groups were injected subcutaneously with 1 ml of PBS. The experimental period was 45 days. Data indicated that body weight of lambs at the end of the study were statistically non-significant among the groups. Blood metabolites, i.e. total protein, albumin, calcium and phosphorus concentrations were not affected significantly by MOS supplementation. However, administration E. coli lowered (p < 0.05) total protein, albumin and calcium concentrations in the serum on day 30. The IgG level was not different between groups. However, on day 45, the total IgG level was found to be higher (p < 0.05) in lambs that had received MOS and E. coli than in other groups. Application of MOS did not have any effect on the antibody response to E. coli as OD values.  相似文献   
56.
Background:  Eradication rates of Helicobacter pylori have declined to unacceptable levels in recent years. New and effective treatment options are warranted both as a first and second line treatment.
Aim:  To test an effectiveness of modified sequential therapy with levofloxacin for H. pylori eradication in Turkey.
Material and Methods:  Helicobacter pylori infected dyspeptic patients were included to the study. Subjects were treated with modified sequential therapy consisting of rabeprazole 20 mg b.i.d. and amoxicillin 1 g b.i.d., for 7 days followed by rabeprazole 20 mg b.i.d, levofloxacin 500 mg q.d. and metronidazole 500 mg b.i.d for the remaining 7 days.
Results:  Sixty-three treatment naive patients and 37 previous treatment failures were enrolled to the study (59 F, 41 M, age: 21–80 years). There was five drop out. Helicobacter pylori eradication was achieved in 80 patients, intention-to-treat (ITT): 80% (95% CI: 71–87%) and per-protocol (PP): 84.2% (95% CI: 75–91%), totally. In treatment naive patients ITT and PP eradication rates were 82.5% (95% CI: 71–91%), and 86.7% (95% CI: 75–94%), respectively. As a second line treatment eradication was successful in ITT 75.7%.(95% CI: 59–88%), and PP 80% (95% CI: 63–92%).Mild side effects were reported by 8 patients (8.4%).
Conclusions:  Sequential therapy using "rabeprazole and amoxicillin 7 days followed by rabeprazole, metronidazole and levofloxacin for 7 days" is a new regimen with acceptable eradication rates in naïve patients in Turkey. Further modifications in the dose or duration of this new sequential therapy might increase its effectiveness as both first and second line treatment.  相似文献   
57.
There are strong indications, but as yet no proof, that extended  48-bp Flp recombinase targets (FRTs) represent unique targets in all eukaryotic genomes investigated, and that recombinase-mediated cassette exchange is not hampered by the occurrence of genomic pseudo sites. This encouraged the present study in which we explore the feasibility of exchanging, in a given cell, two distinct genomically anchored cassettes, each flanked by a unique set of two heterospecific FRT sites. Mutant FRTs have to meet two major prerequisites for successful recombinase-mediated cassette exchange: (i) a self-recognition capacity comparable to a pair of FRT wild-type sites (FRT × FRT  ), and (ii) a negligible cross-interaction if part of a set of heterospecific sites (F′ × F). We apply a two-step strategy to explore various newly created FRT spacer mutants for these properties. As a result of our screening steps, we identify combinations of sites that are successfully applied to parallel Flp-mediated genomic targeting (“multiplexing”) reactions (i.e., the simultaneous exchange of two separate target cassettes in a given cell).  相似文献   
58.
Alkaptonuria (ochronosis) is a rare autosomal recessive disorder featuring a genetic error in the amino acid metabolism. A defect in the tyrosine metabolism results in the accumulation and deposition of homogentisic acid in connective tissue, causing a blue-black discolouration. Degenerative arthropathy of the spine, knee, and hip are common signs of ochronosis in older age. An association between ochronosis and depression has not previously been discussed in the literature. This case report describes a 69 year-old woman with diabetes mellitus, ochronosis, depression and chronic pain.  相似文献   
59.
An olive (Olea europaea L.) β-glucosidase was purified to apparent homogeneity by salting out with ammonium sulfate and using specifically designed sepharose-4B-L-tyrosine-1-napthylamine hydrophobic interaction chromatography. The purification was 155 fold with an overall enzyme yield of 54%. The molecular mass of the protein was estimated as ca. 65 kDa. The purified β-glucosidase was effectively active on p-/o-nitrophenyl-β-D-glucopyranosides (p-/o-NPG) with K(m) values of 2.22 and 14.11 mM and V(max) values of 370.4 and 48.5 U/mg, respectively. The enzyme was competitively inhibited by δ-gluconolactone and glucose against p-NPG as substrate. The K(i) and IC(50) values of δ-gluconolactone were determined as 0.016 mM and 0.23 mM while the enzyme was more tolerant to glucose inhibition with K(i) and IC(50) values of 6.4 mM and 105.5 mM, respectively, for p-NPG. The effect of various metal ions on the purified β-glucosidase was investigated. Of the ions tested, only the Fe(2+) increased the activity while Cd(2+) Pb(2+) Cu(2+), Ni(+), and Ag(+) exhibited different levels of inhibitory effects with K(i) and IC(50) values of 4.29×10(-4) and 0.38×10(-4), 1.26×10(-2) and 5.3×10(-3), 2.26×10(-4) and 6.1×10(-4), 1.04×10(-4) and 0.63×10(-4), 3.21×10(-3) and 3.34×10(-3) mM, respectively.  相似文献   
60.

Background

Metabolic syndrome (MetS) is a prevalent risk factor for cardiac dysfunction. Although SGLT2-inhibitors have important cardioprotective effects in hyperglycemia, their underlying mechanisms are complex and not completely understood. Therefore, we examined mechanisms of a SGLT2-inhibitor dapagliflozin (DAPA)-related cardioprotection in overweight insulin-resistant MetS-rats comparison with insulin (INSU), behind its glucose-lowering effect.

Methods

A 28-week high-carbohydrate diet-induced MetS-rats received DAPA (5 mg/kg), INSU (0.15 mg/kg) or vehicle for 2 weeks. To validate MetS-induction, we monitored all animals weekly by measuring body weight, blood glucose and HOMO-IR index, electrocardiograms, heart rate, systolic and diastolic pressures.

Results

DAPA-treatment of MetS-rats significantly augmented the increased blood pressure, prolonged Q–R interval, and low heart rate with depressed left ventricular function and relaxation of the aorta. Prolonged-action potentials were preserved with DAPA-treatment, more prominently than INSU-treatment, at most, through the augmentation in depressed voltage-gated K+-channel currents. DAPA, more prominently than INSU-treatment, preserved the depolarized mitochondrial membrane potential, and altered mitochondrial protein levels such as Mfn-1, Mfn-2, and Fis-1 as well as provided significant augmentation in cytosolic Ca2+-homeostasis. Furthermore, DAPA also induced significant augmentation in voltage-gated Na+-currents and intracellular pH, and the cellular levels of increased oxidative stress, protein-thiol oxidation and ADP/ATP ratio in cardiomyocytes from MetS rats. Moreover, DAPA-treatment normalized the increases in the mRNA level of SGLT2 in MetS-rat heart.

Conclusions

Overall, our data provided a new insight into DAPA-associated cardioprotection in MetS rats, including suppression of prolonged ventricular-repolarization through augmentation of mitochondrial function and oxidative stress followed by improvement of fusion–fission proteins, out of its glucose-lowering effect.
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