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81.
Changes in serum biochemical parameters of freshwater fish Oreochromis niloticus following prolonged metal (Ag, Cd, Cr, Cu, Zn) exposures 总被引:1,自引:0,他引:1
Fish serum may reflect status of many biochemical processes in the metabolism. Heavy metals, as environmental stressors, may alter serum biochemical parameters in fishes. Thus, freshwater fish, Oreochromis niloticus, were exposed to low levels (0.05 mg/L) of metals (silver [Ag], cadmium [Cd], copper [Cu], chromium [Cr], zinc [Zn]) to investigate responses of serum biochemical parameters over different exposure periods (0, 5, 10, 20, 30 d). Fish mortality occurred only in Ag exposure, as all fish died between days 12 to 16. Activities of alkaline phosphatase (ALP), alanine transaminase (ALT), and aspartate transaminase (AST) were altered only in Cu- and Cd-exposed fish. Both Cd and Cu exposures decreased the activity of ALP, although they increased the activities of ALT and AST. Glucose concentrations increased in Ag-, Cd-, and Cu-exposed fish, with a sharp increase occurring in Ag-exposed fish before mortality began. Total protein and triglyceride concentrations increased in Ag-exposed fish, although they decreased in Cu-exposed ones. However, all metal exposures increased cholesterol concentration in the serum. Concentration of blood urea nitrogen increased in Ag-, Cd-, and Cu-exposed fish, although it decreased in Cr-exposed ones. Calcium level decreased only in Cu-exposed fish, and Cl(-) level decreased in Ag-exposed fish. Silver and Cu exposures also decreased Na(+) level in the serum. Cadmium and Cu exposures increased serum K(+) levels. The present study, investigating the effects of environmentally realistic metal exposures on serum biochemical parameters, demonstrated that fish serum could sensitively reflect environmental metal stress. Thus, it suggests that serum biochemical parameters could be used as important and sensitive biomarkers in ecotoxicological studies concerning the effects of metal contamination and fish health. 相似文献
82.
83.
Kisli E Kisli M Agargun H Altinokyigit F Kamaci M Ozman E Kotan C 《The Tohoku journal of experimental medicine》2006,210(4):365-372
Repeated deliveries might disturb the levator function and increase defecation disorders. In this prospective study, we determined the electric activity of the levator ani muscle (LAM) in nullipara, multipara, grand multipara, and great grand multipara (20 subjects for each group). Multiparity, grand multiparity, and great grand multiparity were defined as women having 2 - 5, 6 - 9, and 10 and over deliveries, respectively. The number of deliveries of multipara, grand multipara and great grand multipara were 4.05 +/- 1.14 (2 - 5), 7.55 +/- 1.23 (6 - 9) and 12.2 +/- 2.16 (10 - 17), respectively. All women were asked whether they had experienced constipation, fecal or urinary incontinence, and/or pelvic pain. All women were also evaluated for pelvic organ prolapse. Electromyography (EMG) of the LAM at rest and on contraction was recorded. EMG is an electrical recording of muscle activity. Constipation, incontinence and pelvic organ prolapse were encountered in multipara, grandmultipara and great grand multipara women. The LAM EMG at rest and on contraction in the nullipara was accepted as control. Both the resting and contractile activities of the LAM were as follows: nullipara > multipara > grand multipara > great grand multipara. These findings indicate that levator dysfunction and defecation disorders are increased with repeated deliveries because of pudendal and/or levator ani nerve injury and traumatic injury to the LAM occurred with the mechanical stresses of vaginal deliveries. 相似文献
84.
PURPOSE: To investigate the effects of microwave frequency electromagnetic fields (EMF) on the development of Drosophila melanogaster. MATERIALS AND METHODS: Larvae of D. melanogaster were exposed to 10 GHz EMF continuously (3 h, 4 h and 5 h) and discontinuously (3 h exposure + 30 min interval + 3 h exposure). The percentages and times of transition from larvae to pupae and from pupae to adults were determined, and the mean offspring number was examined using the offspring of the females which had been exposed as larvae. RESULTS: No differences were found in the transition percentages from larvae to pupae and from pupae to adults (p > 0.05). However, it was found that the mean pupation time was delayed linearly with an increasing electromagnetic field (EMF) exposure period (p < 0.05). In the 3 + 3-h exposed group (E3 + 3), the mean offspring number was significantly less than that of the control (p < 0.05). CONCLUSIONS: 10 GHz EMF can cause developmental delay and decrease the number of offspring in D. melanogaster. 相似文献
85.
The objective of this study was to investigate the clinical predictors of response to treatment with selective serotonin reuptake inhibitors (SSRI) in a sample of patients with obsessive-compulsive disorder (OCD). A total of 55 patients diagnosed as OCD according to revised 3rd edition of the Diagnostic and Statistical Manual of Mental Disorders criteria underwent a 12-week standardized SSRI treatment. According to 'treatment response', defined as at least a 35% drop in the Yale-Brown Obsessive-Compulsive Scale total score, OCD patients were divided into two groups. A total of 32 (58.2%) patients who responded to treatment and 23 (41.8%) who did not, were compared in terms of sociodemographic and clinical characteristics. The authors' findings demonstrated that the severity of obsession-compulsions and disability in work, social and family lives at the beginning of treatment were significantly higher in OCD patients who did not respond to treatment in comparison to those who did. Linear regression analysis, however, revealed that Sheehan Disability Scale-work score at baseline was a predictor of response to SSRI treatment. The higher levels of disability at the beginning of treatment in patients with OCD are associated with a poorer response to SSRI. 相似文献
86.
Etienne Lemaire Damien Thuau Jean-Baptiste De Vaulx Nicolas Vaissiere Atli Atilla 《Materials》2021,14(20)
More than one century ago, piezoelectricity and ferroelectricity were discovered using Rochelle salt crystals. Today, modern societies are invited to switch to a resilient and circular economic model. In this context, this work proposes a method to manufacture piezoelectric devices made from agro-resources such as tartaric acid and polylactide, thereby significantly reducing the energy budget without requiring any sophisticated equipment. These piezoelectric devices are manufactured by liquid-phase epitaxy-grown Rochelle salt (RS) crystals in a 3D-printed poly(Lactic acid) (PLA) matrix, which is an artificial squared mesh which mimics anatomy of natural wood. This composite material can easily be produced in any fablab with renewable materials and at low processing temperatures, which reduces the total energy consumed. Manufactured biodegradable samples are fully recyclable and have good piezoelectric properties without any poling step. The measured piezoelectric coefficients of manufactured samples are higher than many piezoelectric polymers such as PVDF-TrFE. 相似文献
87.
BackgroundAsymptomatic bacteriuria (ASB) is common among the older persons. Several factors may precipitate ASB, including age-related changes in genitourinary system and comorbid diseases. Unnecessary antibiotic use for ASB could be associated with increased antibiotics resistance. The aim of this study was to determine the prevalence and related factors of ASB among the elderly living in the community.MethodsIn this study, 625 patients admitted to our geriatric outpatient clinic were enrolled. Comprehensive geriatric and physical assessment, a standardized questionnaire, medical history, and urine and blood sampling were performed. ASB was defined as identical microorganisms isolated from two consecutive urine specimens (≥ 105 colony-forming units/mL).ResultsMean age of patients was 72.4 ± 5.6 and 394 (63%) were female. The prevalence of ASB was 6.2%. Whereas female gender was associated with ASB, presence of ASB was not associated with age, previous urinary tract infection (UTI), urolithiasis, genitourinary surgery, and/or urinary incontinence. Similarly, diabetes mellitus (DM), obesity, hypertension, and creatinine clearance were not found to be associated with presence of ASB. Laboratory results were similar in the subjects with or without ASB. The most commonly isolated organism was Escherichia coli (66.7%). In addition, while the specificity of leukocyte-esterase and nitrite were high, the sensitivity of both tests was low in the subjects with ASB.ConclusionsThese results indicate that ASB is common and the main risk factor for ASB is female gender among non-institutionalized elderly. E. coli were the most commonly isolated bacterium. Urine dipstick tests seem to be useful in older persons to exclude the presence of bacteriuria. 相似文献
88.
Avci A Atli T Ergüder IB Varli M Devrim E Turgay SA Durak I 《Experimental aging research》2007,33(4):429-437
The effects of apple consumption on plasma and erythrocyte antioxidant parameters of elderly subjects were investigated in this study. Fifteen elderly subjects (mean age 71.86 +/- 4.17) participated in the study. They consumed an apple a day for 1 month. Before and after this period, fasting blood samples were obtained, and oxidant (malondialdehyde [MDA]) and antioxidant (superoxide dismutase [SOD], glutathione peroxidase [GSH-Px], catalase [CAT], and antioxidant potential [AOP]) parameters were studied. MDA and AOP levels were studied in plasma, and SOD, GSH-Px, and CAT activities and MDA levels were measured in the erythrocytes. In the erythrocytes, GSH-Px and SOD activities were found to be higher (p < .001 and p < .01), but MDA levels were lower in the second samples relative to the first ones. In the plasma, AOP value was found to be higher in the second samples relative to first ones (p < .001). No differences were found, however, between the routine blood parameters such as total cholesterol, low-density lipoprotein cholesterol, very-low-density lipoprotein cholesterol, high-density-lipoprotein cholesterol, and triglyceride levels. The results show that consumption of apple leads to significant increases in the activities of some antioxidant enzymes and in the antioxidant potential values of the blood, and that decreases oxidation reactions in the body in significant amount. It is quite possible that reduced peroxidation processes owing to consumption of this fruit may play a part in some of their beneficial effects in the elderly subjects. 相似文献
89.
As a first attempt, a study was carried out to test for lovastatin production ability in local higher Basidiomycetes mushroom isolates from Turkey. An extended screening was performed for lovastatin production in yeast lactose agar medium, among a total of 136 macrofungi isolates from the Basidiomycetes Culture Collection of Eskisehir Osmangazi University. Lovastatin production was evaluated by disc diffusion method and was also confirmed by TLC and HPLC. Only six isolates were found to be lovastatin producers. The highest production of lovastatin was obtained from the extracts from Omphalotus olearius OBCC 2002 and Pleurotus ostreatus OBCC 1031. The lovastatin amount produced by commercial strains, Aspergillus terreus NRRL 255 (7.0 mg/L) and Penicillium citrinum NRRL 1841 (7.0 mg/L), was nearly comparable to the amount produced by Pleurotus ostreatus OBCC 1031 (5.8 mg/L) and Omphalotus olearius OBCC 2002 (4 mg/L). 相似文献
90.
Freshwater fish Oreochromis niloticus were individually acutely exposed to different concentrations (0, 0.1, 0.5, 1.0, and 1.5 μg/mL) of Cd2+, Cr6+, and Ag+ for 96 h and 0.05 μg/mL concentration of the same metals for different periods (0, 5, 10, 20, and 30 days) chronically. Following each experimental protocol, Na+/K+‐ATPase, Mg2+‐ATPase, and Ca2+‐ATPase activities were measured in the gill, kidney, and muscle of O. niloticus. In vitro experiments were also performed to determine the direct effects of metal ions (0, 0.1, 0.5, 1.0, and 1.5 μg/mL) on ATPases. Except Ag+, none of the metals caused fish mortality within 30 days. Silver killed all the fishes within 16 days. Metal exposures generally decreased Na+/K+‐ATPase and Ca2+‐ATPase activities in the tissues of O. niloticus, although there were some fluctuations in Mg2+‐ATPase activity. Ag+ and Cd2+ were found to be more toxic to ATPase activities than Cr6+. It was also observed that metal efficiency was higher in the gill than in the other tissues. Results indicated that the response of ATPases varied depending on metals, exposure types, and tissues. Because ATPases are sensitive to metal toxicity, their activity can give valuable data about fish physiology. Therefore, they may be used as a sensitive biomarker in environmental monitoring in contaminated waters. © 2011 Wiley Periodicals, Inc. Environ Toxicol 28: 707–717, 2013. 相似文献