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1.
Nitrate-rich food can increase nitric oxide production and improve vascular and brain functions. This study examines the feasibility of a randomised controlled trial (RCT) testing the effects of prolonged consumption of different doses of dietary nitrate (NO3) in the form of beetroot juice (BJ) in overweight and obese older participants. A single-blind, four-arm parallel pilot RCT was conducted in 62 overweight and obese (30.4 ± 4 kg/m2) older participants (mean ± standard deviation (SD), 66 ± 4 years). Participants were randomized to: (1) high-NO3 (HN: 2 × 70 mL BJ/day) (2) medium-NO3 (MN: 70 mL BJ/day), (3) low-NO3 (LN: 70 mL BJ on alternate days) or (4) Placebo (PL: 70 mL of NO3-depleted BJ on alternate days), for 13 weeks. Compliance was checked by a daily log of consumed BJ, NO3 intake, and by measuring NO3 and NO2 concentrations in plasma, saliva, and urine samples. Fifty participants completed the study. Self-reported compliance to the interventions was >90%. There were significant positive linear relationships between NO3 dose and the increase in plasma and urinary NO3 concentration (R2 = 0.71, p < 0.001 and R2 = 0.46 p < 0.001, respectively), but relationships between NO3 dose and changes in salivary NO3 and NO2 were non-linear (R2 = 0.35, p = 0.002 and R2 = 0.23, p = 0.007, respectively). The results confirm the feasibility of prolonged BJ supplementation in older overweight and obese adults.  相似文献   
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This study was designed to investigate the possible protective effect of lycopene against the renal toxic effects of OTA. Male Sprague-Dawley rats (<200 g, n = 6) were treated with OTA (0.5 mg/kg/day) and/or lycopene (5 mg/kg/day) by gavage for 14 days. Histopathological examinations were performed and apoptotic cell death in both cortex and medulla was evaluated by TUNEL assay. Besides, biochemical parameters and activities of renal antioxidant selenoenzymes [glutathione peroxidase 1 (GPx1), thioredoxin reductase (TrxR)], catalase (CAT), superoxide dismutase (SOD); concentrations of total glutathione (GSH), and malondialdehyde (MDA) levels were measured. OTA treatment was found to induce oxidative stress in rat kidney, as evidenced by marked decreases in CAT (35%) activity and GSH levels (44%) as well as increase in SOD activity (22%) vs control group. Furthermore, TUNEL analysis revealed a significant increase in the number of TUNEL-positive cells in cortex (49%) and medulla (75%) in OTA administrated group compared to control (p < 0.05). Lycopene supplementation with OTA increased GPx1 activity and GSH levels, and decreased apoptotic cell death in both cortex and medulla vs. control. The results of this study showed that at least one of the mechanisms underlying the renal toxicity of OTA is oxidative stress and apoptosis is the major form of cell death caused by OTA. Besides, our data indicate that the natural antioxidant lycopene might be partially protective against OTA-induced nephrotoxicity and oxidative stress in rat.  相似文献   
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Campylobacter spp. is a leading cause of diarrheal disease among US troops deployed to Thailand for exercise. We investigated the importance of immunological analysis and immune responses against Campylobacter infection in US troops deployed to Thailand. Blood and fecal samples were collected from volunteered soldiers with diarrhea and from healthy controls. Stool culture was performed to identify the pathogens. Campylobacter‐specific antibodies, antibody secreting cells and cytokines were measured. Several bacterial protein fragments in the outer membrane extract of Campylobacter spp., were identified by an immunoblot analysis with plasma and fecal antibodies. Among all of the diarrheal cases, 35% were Campylobacter‐positive. Based on antibody titers in plasma and in fecal extract and antibody secreting cells: 6% of healthy controls, 32% of the Campylobacter culture‐negative diarrheal cases, and 85% of the Campylobacter culture‐positive diarrheal cases were positive for Campylobacter. Our results indicate that the measurement of Campylobacter‐specific antibodies in plasma and fecal extract samples is a good marker of exposure to Campylobacter, and this test may be a useful diagnostic tool for seroepidemiological studies. Elicited antibodies against several bacterial outer membrane protein fragments suggest that these protein fragments are vital in providing protective immunity against Campylobacter.  相似文献   
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The nationwide seroprevalence of hepatitis E IgG was determined among young men in Thailand. Overall seroprevalence was 14% (95% CI 13%–15%); range by province was 3%–26%. Seroprevalence was lowest in the south, an area predominantly occupied by persons of the Islam religion, whose dietary laws proscribe pork.  相似文献   
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European Journal of Clinical Microbiology & Infectious Diseases - Since its emergence in December 2019, SARS-CoV-2 is causing one of the most devastating pandemics in human history. Currently,...  相似文献   
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Shigellosis is a worldwide disease, characterized by abdominal pain, fever, vomiting, and the passage of blood‐ and mucus‐streaked stools. Rhesus monkeys and other primates are the only animals that are naturally susceptible to shigellosis. A suitable animal model is required for the pre‐clinical evaluation of vaccines candidates. In this study, the minimal dose of Shigella dysenteriae1 1617 strain required to produce dysentery in four of five (80% attack rate) monkeys using an escalating dose range for three groups [2 × 108, 2 × 109 and 2 × 1010 colony forming unit (CFU)] was determined. In addition, the monkeys were re‐infected. The identified optimal challenge dose was 2 × 109 CFU; this dose elicited 60% protection in monkeys when they were re‐challenged with a one log higher dose (2 × 1010 CFU). The challenge dose, 2 × 1010 CFU, produced severe dysentery in all monkeys, with one monkey dying within 24 h, elicited 100% protection when re‐challenged with the same dose. All monkeys exhibited immune responses. This study concludes that the rhesus monkey model closely mimics the disease and immune response seen in humans and is a suitable animal model for the pre‐clinical evaluation of Shigella vaccine candidates. Prior infection with the 1617 strain can protect monkeys against subsequent re‐challenges with homologous strains.  相似文献   
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Parambil JG  Savci CD  Tazelaar HD  Ryu JH 《Chest》2005,127(4):1178-1183
BACKGROUND: Although pulmonary infarction is usually associated with pulmonary thromboembolism, it can occur with other disorders such as vasculitis, angioinvasive infections, sickle-cell disease, tumor embolism, and pulmonary torsion. STUDY OBJECTIVE: To identify causes and presenting features of pulmonary infarctions diagnosed by surgical biopsy in a consecutive series of patients encountered at a single institution. DESIGN: Retrospective review. SETTING: Tertiary care, referral medical center. PATIENTS: Forty-three patients with pulmonary infarction identified on surgical lung biopsy over a period of 7 years, January 1996 through December 2002. RESULTS: The median age of these 43 patients was 55 years (range, 22 to 85 years); 17 patients (40%) were women, and 26 patients (60%) were men. Thirty-five patients (81%) had a smoking history. Twenty-eight patients (65%) presented with solitary or multiple lung nodules/masses of undetermined etiology. The underlying cause was identifiable in 31 cases (72%) based on a review of clinical, laboratory, radiologic, and histopathologic data. The two most common causes were pulmonary thromboembolism (18 cases, 42%) and pulmonary infections (5 cases, 12%). Thromboembolic pulmonary infarctions typically presented as solitary or multiple nodules located in the subpleural regions. Other causes included diffuse alveolar damage in two cases (5%), pulmonary torsion in two cases (5%), and one case each of lung cancer, amyloidosis, embolotherapy, and catheter embolism. In 12 cases (28%), the underlying cause was not directly identifiable but was probably due to previous pulmonary thromboembolism. CONCLUSION: We conclude that although pulmonary thromboembolism is the most common cause of pulmonary infarction identified by surgical lung biopsy, a variety of other causes are clinically encountered, including infections, inflammatory or infiltrative lung diseases, pulmonary torsion, malignancy, and nonthrombotic embolism. Pulmonary infarction should be considered in the differential diagnosis of peripheral lung nodules or masses.  相似文献   
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