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41.
The effect of monosodium glutamate (MSG) on the histogenesis of bone and bone marrow of mice is studied. Intraperitoneal-subcutaneous injections and oral administration of the drug MSG induced marked repression in the ossification of developing endochondral bone with the persistence of cartilagenous elements and chondrocytes. A massive accumulation of adipose tissue accompanied by receded haemopoietic tissue within the bone marrow is observed in the MSG-treated animals. These pathological changes are attributed to the influence of the drug on the hydrolysis of enzyme alkaline phosphatase, glycolysis involved in the bone deposition or on the secretion of hormones responsible for bone resorption.  相似文献   
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Summary Okra plants were exposed to chilling temperatures of 5° or 10°C for various periods up to 144 hours in a controlled environment room. Controls were maintained in a similar room at 25°C. Seedling plants which had developed five true leaves and plants in a preflowering condition with well developed buds were used. Results showed that injury occurred at both 5° and 10°C in plants at both growth stages. Seedling plants exposed at 5°C for 144 hours were killed while the older ones died back to the lower nodes. Eventually growth occurred from the buds at these nodes. In cases where the plants survived there was a delay in flowering and a decrease in the total number of flowers. Increased cold exposure resulted in an increased percentage dry matter. It appeared that increased dessication contributed to injury, but that atmospheric humidity itself had little relationship to injury. The insoluble nitrogen fraction did not show any great change. There was an increase in some amino acids, and it was noted that these were the same as those derived from pyruvate. The soluble protein fraction did not change. It was suggested that this lack of change might be a manifestation of the difference between plants that can be hardened and those that cannot.  相似文献   
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We wished to determine the severity of posthypoxic ventilatory decline in patients with sleep apnea relative to normal subjects during sleep. We studied 11 men with sleep apnea/hypopnea syndrome and 11 normal men during non-rapid eye movement sleep. We measured EEG, electrooculogram, arterial O(2) saturation, and end-tidal P(CO2). To maintain upper airway patency in patients with sleep apnea, nasal continuous positive pressure was applied at a level sufficient to eliminate apneas and hypopneas. We compared the prehypoxic control (C) with posthypoxic recovery breaths. Nadir minute ventilation in normal subjects was 6.3 +/- 0.5 l/min (83.8 +/- 5.7% of room air control) vs. 6.7 +/- 0.9 l/min, 69.1 +/- 8.5% of room air control in obstructive sleep apnea (OSA) patients; nadir minute ventilation (% of control) was lower in patients with OSA relative to normal subjects (P < 0.05). Nadir tidal volume was 0.55 +/- 0.05 liter (80.0 +/- 6.6% of room air control) in OSA patients vs. 0.42 +/- 0.03 liter, 86.5 +/- 5.2% of room air control in normal subjects. In addition, prolongation of expiratory time (Te) occurred in the recovery period. There was a significant difference in Te prolongation between normal subjects (2.61 +/- 0.3 s, 120 +/- 11.2% of C) and OSA patients (5.6 +/- 1.5 s, 292 +/- 127.6% of C) (P < 0.006). In conclusion, 1) posthypoxic ventilatory decline occurred after termination of hypocapnic hypoxia in normal subjects and patients with sleep apnea and manifested as decreased tidal volume and prolongation of Te; and 2) posthypoxic ventilatory prolongation of Te was more pronounced in patients with sleep apnea relative to normal subjects.  相似文献   
46.
Primary ciliary dyskinesia (PCD) is a heterogeneous autosomal recessive disease that is caused by impaired ciliary and flagellar functions. About 50% of PCD patients show situs inversus, denoted as Kartagener syndrome. In most cases, axonemal defects in cilia and sperm tails can be demonstrated by electron microscopy, i.e. PCD patients often lack inner and/or outer dynein arms in their sperm tails and cilia, supporting the hypothesis that mutations in dynein genes may cause PCD. In order to identify novel PCD genes we have isolated the human ortholog of the murine TCTE3 gene. The human TCTE3 gene encodes a dynein light chain and shares high similarity to dynein light chains of other species. The TCTE3 gene is expressed in tissues containing cilia or flagella, it is composed of four exons and located on chromosome 6q25-->q27. To elucidate the role of TCTE3 as a candidate gene for PCD a mutational analysis of thirty-six PCD patients was performed. We detected five polymorphisms in the coding sequence and in the 5' UTR of the TCTE3 gene. In one patient a heterozygous nucleotide exchange was identified resulting in an arginine to isoleucine substitution at the amino acid level. However, this exchange was also detected in one control DNA. Our results indicate that mutations in the TCTE3 gene are not a main cause of primary ciliary dyskinesia.  相似文献   
47.
Nephronophthisis, an autosomal-recessive cystic kidney disease, is the most frequent monogenic cause for renal failure in childhood. Infantile and juvenile forms of nephronophthisis are known to originate from separate gene loci. We describe here a new disease form, adolescent nephronophthisis, that is clearly distinct by clinical and genetic findings. In a large, 340-member consanguineous Venezuelan kindred, clinical symptoms and renal pathology were evaluated. Onset of terminal renal failure was compared with that in a historical sample of juvenile nephronophthisis. Onset of terminal renal failure in adolescent nephronophthisis occurred significantly later (median age 19 years, quartile borders 16.0 and 25.0 years) than in juvenile nephronophthisis (median age 13.1 years, quartile borders 11.3 and 17.3 years; Wilcoxon test P=.0069). A total-genome scan of linkage analysis was conducted and evaluated by LOD score and total-genome haplotype analyses. A gene locus for adolescent nephronophthisis was localized to a region of homozygosity by descent, on chromosome 3q22, within a critical genetic interval of 2. 4 cM between flanking markers D3S1292 and D3S1238. The maximum LOD score for D3S1273 was 5.90 (maximum recombination fraction.035). This locus is different than that identified for juvenile nephronophthisis. These findings will have implications for diagnosis and genetic counseling in hereditary chronic renal failure and provide the basis for identification of the responsible gene.  相似文献   
48.
Two experiments were done in 2008 and 2009 to study the effects of magnetic field and silver nanoparticles on fodder maize (Zea mays L.). These experiments were done with seven treatments based on a randomized complete block design in four replications. The treatments were as follows: magnetic field and silver nanoparticles?+?Kemira fertilizer (T1), magnetic field and silver nanoparticles?+?Humax fertilizer (T2), magnetic field and silver nanoparticles (T3), Kemira fertilizer (T4), Librel fertilizer (T5), Humax fertilizer (T6), and a control (T7). Results showed that fresh yield was higher in treatments T3 and T4. Treatments T3 and T4 had increased maize fresh yields of 35 and 17.5?% in comparison to the control, respectively. The dry matter yield of those plants exposed to magnetic field and silver nanoparticles was significantly higher than that from any of the other treatments. Magnetic field and silver nanoparticle treatments (T3 and T1) showed higher percentages for ears, and the lowest percentages were found in treatments T7 and T5. In general, the soil conditions for crop growth were more favorable in 2009 than in 2008, which caused the maize to respond better to treatments tested in the study; therefore, treatments had more significant effects on studied traits in 2008 than in 2009.  相似文献   
49.
Enzymes in mitochondria play an important role in biological oxidation and energy production. To understand the effect of schistosomiasis on these important processes, succinate cytochrome c reductase (SCR) from control and Schistosoma-infected mice was subjected for investigation. In this article, we report that SCR from Schistosoma-infected mouse showed a significant decrease in its V max and K m compared to control using both cytochrome c and 2,6-dichlorophenolindophenol as substrates. Furthermore, the kinetic studies of the purified SCR in the absence and presence of the schistosomicidal drugs praziquantel and Commiphora extract reveal that both drugs have an inhibitory action on the enzyme from the control and Schistosoma-infected mice and praziquantel changes the type of inhibition of SCR towards cytochrome c from mixed type in control to a competitive one in the case of the infection.  相似文献   
50.
The present study was undertaken to investigate the utility of cystatin C (CysC) as an early biomarker of cadmium (Cd)-induced renal injury. The study was carried out on 50 adult male individuals divided into five groups of 10 individuals as follows: control, welders, smoker welders, diabetic welders, and smoker diabetic welders. The results indicated that plasma levels of CysC, creatinine, urea, and uric acid were significantly higher in welders compared to control individuals. In addition, the levels of whole blood Cd, lipid peroxidation, and protein oxidation products as well as erythrocyte osmotic fragility were significantly higher in welders compared to control individuals. In contrast, the levels of plasma albumin and whole blood glutathione were significantly decreased in welders compared to control individuals. The alterations of the measured parameters were enhanced in the presence of smoking and hyperglycemia besides exposure to welding fumes. These results suggest that CysC can be used as a sensitive biomarker of the early stages of Cd-induced renal injury.  相似文献   
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