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41.
Hypermethylated genomic DNA is a common feature in tumoral tissues, although the prevalence of this modification remains poorly understood. We aimed to determine the frequency of five tumor suppressor (TS) genes in prostate cancer and the correlation between promoter hypermethylation of these genes and low and high grade of prostate carcinomas. A total of 30 prostate tumor specimens were investigated for promoter methylation status of TS hypermethylated in cancer 1 (HIC1), death-associated protein kinase 1 (DAPK1), secreted frizzled-related protein 2 (SFRP2), cyclin-dependent kinase inhibitor 2A (p16), and O-6-methylguanine-DNA methyltransferase (MGMT) genes by using bisulfite modifying method. A high frequency of promoter hypermethylation was found in HIC1 (70.9%), SFRP2 (58.3%), and DAPK1 (33.3%) genes in tumor samples that were examined. The current data show high frequency of hypermethylation changes in HIC1, SFRP2, and DAPK1 genes in prostate carcinomas of high Gleason Score (GS).  相似文献   
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Endotoxin decreases mesenteric blood flow and inflicts organ injury via free radicals. We investigated whether taurine, an endogenous antioxidant and vasodilator, could attenuate the deleterious effects of endotoxin in a mouse model of sepsis. Swiss albino mice were allocated into four groups and treated either with taurine (150 mg/kg, i.p. at 0(th), 8(th), 16(th) h) or its solvent sterile saline (NaCl 0.9%, w/v) while E. coli endotoxin (20 mg/kg, i.p.) or its solvent saline were also given at 8(th) h. At 24(th) h the animals were anaesthetized and the mesenteric blood flow was measured by using perivascular ultrasonic Doppler-flowmeter. The animals were then exsanguinated, the spleen, liver, and kidneys were isolated for histopathological examination. Thiobarbituric acid-reacting substances (TBARS), glutathione, and myeloperoxidase activity were determined in the liver samples. Endotoxin significantly decreased the mesenteric blood flow and glutathione levels in liver while TBARS and myeloperoxidase activity were increased. However, taurine did not block the deleterious effects of endotoxin nor it did attenuate the histopathological injury. Therefore, we concluded that endotoxin-induced organ injury via free radicals is resistant to blockade by taurine.  相似文献   
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Objective: A recent study suggested that high concentrations of leptin enhance platelet aggregations. Therefore, the aim of this study was to investigate whether platelet aggregation is altered in patients with leptin gene mutations compared with obese subjects or controls. Research Methods and Procedures: Four men (one homozygous man and his three heterozygous brothers) carrying a leptin gene mutation; 20 age‐matched, healthy, unrelated men; and 18 age‐matched obese men were enrolled in the study. Adenosine diphosphate (ADP)‐, collagen‐, and epinephrine‐induced platelet aggregation were evaluated in all individuals. Results: Our results show that patients with the leptin gene mutation (both the homozygous and heterozygous patients) had significantly higher ADP‐induced (78.3 ± 3.4% vs. 57.9 ± 9.3%, p = 0.001), collagen‐induced (78.1 ± 2.9% vs. 56.7 ± 9.3%, p = 0.007), and epinephrine‐induced (76.5 ± 9.2% vs. 59.5 ± 7.70%, p = 0.003) platelet aggregation compared with controls. However, ADP‐, collagen‐, or epinephrine‐induced platelet aggregations were similar to those in obese patients. Platelet aggregation responses to a combination of pretreatment with leptin at concentrations of 20, 50, 100, or 500 ng/mL for 5 minutes and ADP at concentrations of 2 μmol/liter also were evaluated. However, we did not find significant increases in platelet aggregation even at high concentrations of leptin (100 or 500 ng/mL) in leptin‐deficient patients, obese subjects, or controls. Discussion: Our data show that similar to findings in obese humans, homozygous or heterozygous leptin deficiency is associated with increased platelet aggregation compared with controls, and that higher concentrations of leptin do not increase platelet aggregation.  相似文献   
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Obesity is a multifactorial disease developing following impairment of the energy balance. The endocrine system is known to be affected by the condition. Serum thyroid hormones and trace element levels have been shown to be affected in obese children. Changes in serum thyroid hormones may result from alterations occurring in serum trace element levels. The aim of this study was to evaluate whether or not changes in serum thyroid hormone levels in children with exogenous obesity are associated with changes in trace element levels. Eighty-five children diagnosed with exogenous obesity constituted the study group, and 24 age- and sex-matched healthy children made up the control group. Serum thyroid stimulating hormone (TSH), free thyroxine (fT4), free triiodothyronine (fT3), thyroglobulin (TG), selenium (Se), zinc (Zn), copper (Cu), and manganese (Mn) levels in the study group were measured before and at the third and sixth months of treatment, and once only in the control group. Pretreatment fT4 levels in the study group rose significantly by the sixth month (p?=?0.006). Zn levels in the patient group were significantly low compared to the control group (p?=?0.009). Mn and Se levels in the obese children before and at the third and sixth months of treatment were significantly higher than those of the control group (p?=?0.001, p?=?0.001). In conclusion, fT4, Zn, Cu, Mn, and Se levels are significantly affected in children diagnosed with exogenous obesity. The change in serum fT4 levels is not associated with changes in trace element concentrations.  相似文献   
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Lysosomal storage diseases (LSD) are metabolic disorders characterized by accumulation of undegraded material. The mucopolysaccharidoses (MPS) are LSDs defined by the storage of glycosaminoglycans. Previously, we hypothesized that cells affected with LSD have increased energy expenditure for biosynthesis because of deficiencies of raw materials sequestered within the lysosome. Thus, LSDs can be characterized as diseases of deficiency as well as overabundance (lysosomal storage). In this study, metabolite analysis identified deficiencies in simple sugars, nucleotides, and lipids in the livers of MPSI mice. In contrast, most amino acids, amino acid derivatives, dipeptides, and urea were elevated. These data suggest that protein catabolism, perhaps because of increased autophagy, is at least partially fulfilling intermediary metabolism. Thus, maintaining glycosaminoglycan synthesis in the absence of recycled precursors results in major shifts in the energy utilization of the cells. A high fat diet increased simple sugars and some fats and lowered the apparent protein catabolism. Interestingly, autophagy, which is increased in several LSDs, is responsive to dietary intervention and is reduced in MPSVII and MPSI mice fed a high fat diet. Although long term dietary treatment improved body weight in MPSVII mice, it failed to improve life span or retinal function. In addition, the ventricular hypertrophy and proximal aorta dilation observed in MPSVII mice were unchanged by a high fat, simple sugar diet. As the mechanism of this energy imbalance is better understood, a more targeted nutrient approach may yet prove beneficial as an adjunct therapy to traditional approaches.Lysosomal storage disease (LSD)2 typically results from a genetic deficiency of an acid hydrolase (1). The material usually degraded by the enzyme now accumulates in the lysosomes of cells throughout the body. In normal cells, some proportion of the degraded material is exported to the cytosol for reuse, thereby reducing the energy burden on the cell (2, 3). In the case of LSDs, more energy must be diverted to the synthesis of raw material because of the impaired recycling. Thus, this class of disorders presents with an energy imbalance caused by a simultaneous excess of stored material and a deficiency of raw material (4).Deficiencies in lysosomal enzymes involved in glycosaminoglycan (GAG) catabolism result in the mucopolysaccharidoses (MPS) (5). The biochemical, histological, and clinical phenotypes of MPS are likely due to a combination of the adaptations to both lysosomal storage and a deficiency of recycled monosaccharides. Maintaining a normal rate of GAG biosynthesis would require newly imported or synthesized monosaccharides, irrespective of the adaptations to stored material. The increased demand for GAG precursors is likely to be considerable. It has been shown previously in cultured cells that reutilization of catabolites from lysosomal GAG degradation is substantial (2). Therefore, the increased energy burden required for de novo synthesis of GAG precursors might be expected to reduce the levels of stored energy throughout the body. Consistent with this hypothesis, we and others have shown that a number of lysosomal storage diseases have significantly reduced adiposity (4, 68). We showed that the reduced adiposity was not the result of reduced food intake, higher metabolic rate, or lipid malabsorption (4). Furthermore, the missing lipid energy was not found in other tissues (4). However, the total caloric content in the liver was normal and in the form of carbohydrates other than glycogen (4). Enzyme replacement therapy reduced the levels of carbohydrates suggesting that their identity was glycosaminoglycans (4). These data strongly argued that energy was being diverted from potential storage as fat in adipocytes to storage in lysosomes as undegraded glycosaminoglycans. It is unclear how diseased cells are adapting to the energy diversion resulting from the block in recycling and what effect this has on the whole organism.In this study, we identified a number of biochemical and metabolic abnormalities associated with two MPS disorders. The data are consistent with the idea that physiologic malnutrition (9) and altered energy flow (4) are common adaptations in many, if not most LSDs. We also determined the effects of nutritional supplementation on these changes. Many of the metabolic abnormalities approached normal when the animals were placed on a high fat, simple sugar diet. Of particular interest is the fact that autophagy was responsive to dietary intervention and approached normal levels when the animals were fed a high fat diet. This identifies at least one mechanism that contributes to the increased autophagy observed in a number of diverse LSDs (1019). Although long term dietary intervention in MPSVII mice resulted in only minor clinical improvements, a more thorough understanding of this defect may ultimately lead to more targeted metabolic interventions that provide clinical benefit as an adjunct therapy.  相似文献   
47.
Effects of salt stress on the activity of peroxidase (PRX) isozyme and leaf proteins were studied in the three strawberry varieties, Camarosa, Tioga and Chandler. Plants were watered with modified 1/3 Hoagland nutrient solution containing 0 (control), 8.5, 17.0 and 34.0 mM NaCl for 30 days fallowing 20 days acclimation. PRX activity was assayed in leaf extracts and PRX profiles of control and salt treated plants were performed by native polyacrylamide gel electrophoresis (PAGE). During the salt stress Tioga and Camarosa tolerated the cellular damage with less electrolyte leakage while Chandler exhibited a severe cellular damage with the highest (87.5 % in 34.0 mM NaCl treatment) electrolyte leakage. Total soluble protein content was decreased by salinity in Tioga (from 11.35 to 5.86 mg g−1 DW) and Chandler (from 9.35 to 3.90 mg g−1 DW) while it was almost unchanged in Camarosa. Salt stress increased total and specific PRX activity as compared with the control in all the varieties. In native PAGE, one basic isoperoxidase band (Rf=0.27) was observed commonly with different band intensity in all the treatments. Therefore, it might be associated with lignification and recovery of cell membrane damage in strawberry plants under salt stress.  相似文献   
48.
The purpose of this study was to achieve a better therapeutic efficacy and patient compliance in the treatment for vaginitis. Clotrimazole (1%) has been formulated in a vaginal gel using the thermosensitive polymer Pluronic F127 (20%) together with mucoadhesive polymers such as Carbopol 934 and hydroxypropylmethylcellulose (0.2% for both). To increase its aqueous solubility., clotrimazole was incorporated as its inclusion complex with 1∶1 molar ratio with β-cyclodextrin. The inclusion complex was thoroughly characterized using various techniques, including 1H NMR spectroscopy, FT IR spectrophotometry, differential scanning calorimetry, scanning electron microscopy, phase solubility studies, and determination of stability constant (k1∶1). The gelation temperature and rheological behavior of different formulations at varying temperatures were measured. In vitro release profiles of the gels were determined in pH 5.5 citrate buffer. It was observed that complexation with cyclodextrin slowed down the release of clotrimazole considerably. Carbopol 934, on the other hand, was found to interact with β-cyclodextrin, inducing precipitation. As far as rheological properties are concerned, thermosensitive in situ gelling was obtained with formulations containing drug: cyclodextrin complex rather than with free drug. Thus, the optimum formulation for a controlled-release thermosensitive and mucoadhesive vaginal gel was determined to be clotrimazole: β-cyclodextrin 1% with 0.2% hydroxypropylmethylcellulose in Pluronic F127 gel (20%) providing continuous and prolonged release of active material above MIC values.  相似文献   
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