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91.
AimTo investigate how age, sex, and comorbidities affect the survival of hospitalized coronavirus disease 2019 (COVID-19) patients.MethodsWe retrospectively analyzed the records of 4014 consecutive adults hospitalized for COVID-19 in a tertiary-level institution from March 2020 to March 2021.ResultsThe median age was 74 years. A total of 2256 (56.2%) patients were men. The median Charlson-comorbidity-index (CCI) was 4 points; 3359 (82.7%) patients had severe or critical COVID-19. A significant interaction between age, sex, and survival (P < 0.05) persisted after adjustment for CCI. In patients <57 years, male sex was related to a favorable (odds ration [OR] 0.50, 95% confidence interval [CI] 0.29-0.86), whereas in patients ≥57 years it was related to an unfavorable prognosis (OR 1.19, 95% CI 1.04-1.37). Comorbidities associated with inferior survival independently of age, sex, and severe/critical COVID-19 on admission were chronic heart failure, atrial fibrillation, acute myocardial infarction, acute cerebrovascular insult, history of venous thromboembolism, chronic kidney disease, major bleeding, liver cirrhosis, mental retardation, dementia, active malignant disease, metastatic malignant disease, autoimmune/rheumatic disease, bilateral pneumonia, and other infections on admission.ConclusionAmong younger patients, female sex might lead to an adverse prognosis due to undisclosed reasons (differences in fat tissue distribution, hormonal status, and other mechanisms). Patient subgroups with specific comorbidities require additional considerations during hospital stay for COVID-19. Future studies focusing on sex differences and potential interactions are warranted.

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a systemic disease presenting with predominantly respiratory symptoms. Up to 15%-20% of affected individuals develop high inflammatory state and severe intensity of symptoms requiring hospital admission in (1). Age and comorbidities were among the earliest recognized clinical risk factors for adverse disease course, and have consistently been shown to affect the severity of presentation and survival of COVID-19 patients. Unfavorable disease course has been especially associated with chronic metabolic comorbidities, such as arterial hypertension, diabetes mellitus, hyperlipoproteinemia, and obesity (2-7). Charlson comorbidity index (CCI), a summary measure of comorbidities validated as a prognostic tool in a number of chronic and malignant diseases (8,9), has also been associated with an adverse COVID-19 clinical course (10-15).Since elderly patients who are more frail and more prone to more severe COVID-19 are also more burdened with comorbidities, in some patients it is almost impossible to distinguish whether clinical deterioration and adverse clinical outcomes are attributable to COVID-19 or to prior comorbidities. Higher inflammatory state associated with COVID-19 might lead to clinical decompensation of chronic comorbidities, and vice versa, prior comorbidities and elevated baseline inflammatory state might predispose to more severe COVID-19. Due to this complex relationship and the need for better understanding how and to what extent particular comorbidities affect the survival of COVID-19 patients, we aimed to investigate the associations of age, sex, and comorbidities with survival in a large cohort of hospitalized COVID-19 patients treated in our institution. We hypothesized that older age, male sex, and higher comorbidity burden were associated with higher death rates.  相似文献   
92.
This study aims to examine in detail for the first time the cytotoxic profile of twelve choline chloride-based deep eutectic solvents (NADES) against HT-29, Caco-2, MCF-7, and MRC-5 cell lines. All NADES systems were synthesized by microwave synthesis using choline chloride as a hydrogen bond acceptor (HBA) and selected sugars, alcohols, organic acids, and urea as hydrogen bond donors (HBD) with the addition of 20% water (w/w) to all systems. It was observed that the cytotoxic effect predominantly depended on the structure of HBD. Acidic systems, where HBDs were organic acids showed the highest cytotoxic effects in all investigated cell lines. The cytotoxicity depended mostly on the concentration of the NADES system in the cell medium as well as on the chemical constitution of the investigated systems. The highest cytotoxic effects showed acidic systems, especially to the HT-29 cell line. The EC50 value for the citric acid-based system was 3.91 mg mL−1 for the HT-29 cell line which was the most vulnerable to acidic NADES systems.

Light microscopy of HT-29 cells without (control) and after 48 h of treatment with 1% acidic NADES system (ChCl : CitA(1:1)).  相似文献   
93.
Articular (medial femoral condyle) and auricular cartilage (anithelix) was compared as a cell source for the autologous joint repair. Cells isolated from five human cadaveric donors were cultured parallel in the monolayer cultures and in the 3D alginate hydrogel constructs for 1 week. Cell morphology was controlled by the fluorescent microscopy and gene expressions of type I collagen (COL1), type II collagen (COL2), aggrecan (AGR), versican (VER), and elastin (ELS) were analyzed by the real‐time polymerase chain reaction. COL1 and ELS, predominant in the phenotype of auricular biopsy, were statistically lower in the articular biopsies. Even though COL2 and AGR decreased in monolayers of both cell sources, the dedifferentiation process affected auricular cells intensely. Cells embedded in the alginate hydrogel directly after the isolation did not exhibit the dedifferentiated phenotype. Additionally, COL1, COL2, AGR, and VER were comparable between the two sources. ELS however, remained higher in the auricular cells regardless of the culture type. The study indicates that auricular chondrocytes cultured in a 3D environment immediately after the isolation have a neo‐cartilage potential for the articular surface reconstruction. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 943–948, 2009  相似文献   
94.
95.
OBJECTIVE: The goal of the study was to evaluate differences in heart rate variability (HRV) among post-myocardial infarction (MI) patients, depending on their participation in the Croatian war and on established diagnoses of post-traumatic stress disorder (PTSD). METHODS: The study included 34 male war veterans with diagnosed PTSD who had suffered a first MI and 34 age-matched post-MI patients without PTSD. Cardiac autonomic balance was evaluated through HRV analysis. RESULTS: There were no differences in the mean R-R interval or overall HRV between the analyzed groups. Post-MI patients with PTSD had lower values for the square root of the mean of squared successive differences in R-R intervals (p = 0.02), the percentage of R-R intervals that were > or =50 milliseconds different from the previous interval (p = 0.03), and the high-frequency component (p = 0.03) but had higher values for the low-frequency component (p = 0.01) and the low-frequency/high-frequency ratio (p = 0.02), compared with post-MI patients without PTSD. CONCLUSION: Post-MI patients with PTSD have higher sympathetic and lower parasympathetic heart rate modulation activity, compared with patients with MI and no PTSD.  相似文献   
96.
Toxic effects of the antineoplastic drug irinotecan on human blood cells at concentrations of 9.0 microg/ml and 4.6 microg/ml were evaluated in vitro. Using the alkaline and neutral comet assay significantly increased levels of primary DNA damage in lymphocytes were detected. The induction of apoptosis/necrosis, as determined by a fluorescent assay, was also notably increased. Cytogenetic outcomes of the treatment were assessed by the analysis of structural chromosome aberrations and fluorescence in situ hybridization. A significantly higher incidence of chromatid breaks and complex quadriradials was observed. Painted chromosomes 1, 2 and 4 were equally involved in translocations, but only the chromosome 1 was involved in the formation of quadriradials. Sister chromatid exchange analysis was performed in parallel with the analysis of lymphocyte proliferation kinetics. The higher concentration of irinotecan caused almost seven-time increase, while the lower one caused a five-time increase of the basal sister chromatid exchange frequency, accompanied with significant lowering of the lymphocyte proliferation index. Using the cytokinesis-block micronucleus assay, a dose-dependent increase in micronucleus frequency along with the formation of nuclear buds and nucleoplasmic bridges was noticed. Inhibitory effects of irinotecan on enzyme acetylcholinesterase (AChE) were studied in erythrocytes. An IC(50) value of 5.0 x 10(-7) was established. Irinotecan was found to be strong inhibitor of the acetylcholine hydrolysis and to cause a continuous decrease of catalytic activity of AChE. The results obtained on a single donor may contribute to the understanding of irinotecan toxicity, but further in vitro and in vivo studies are essential in order to clarify remaining issues, especially on possible inter-individual variability in genotoxic responses to the drug.  相似文献   
97.
98.
Glycoprotein (GP) Ib-IX-V complex plays an important role in formation of platelet-fibrin clot at the area of damaged vessel wall. One polymorphism of GP Ibalpha, the main component of GP Ib-IX-V complex, is due to variable numbers of tandem repeats (VNTRs) in the macroglycopeptide region of this molecule. We studied the association between the presence of different VNTR alleles of GP Ibalpha and the frequency of coronary heart disease (CHD) among individuals recruited to a large community-based case-cohort study (Atherosclerosis Risk in Communities [ARIC] study). We found that the distribution of VNTR alleles of GP Ibalpha is different among whites and African Americans. The B allele (with 3 repeats) of GP Ibalpha is relatively more common among African Americans compared with whites. In African Americans, the CC genotype (homozygous with 2 repeats) is associated with a lower risk of CHD events than all other genotypes.  相似文献   
99.
K048 is a member of K‐oximes, a new oxime class that has recently been confirmed effective against poisoning by the nerve agent tabun and several pesticides. The toxicity profile of the K048 oxime has not been fully characterized and its optimal therapeutic dose has not yet been established. Earlier studies report excellent results with K048 in reactivating tabun‐phosphorylated AChE and in the therapy of tabun‐poisoned mice. It possesses a low acute toxicity and exerts an acceptable toxicity profile on isolated human peripheral blood lymphocytes in vitro. Intraperitoneal administration of K048 in rats resulted in an LD50 of 238.3 mg/kg. In this in vivo study, we investigated cholinesterase (ChE) activity and oxidative stress marker levels (lipid peroxidation and superoxide dismutase activity) in the plasma of exposed rats after administering the compound at 25% of its LD50. Lymphocyte viability was evaluated using an acridine orange/ethidium bromide in situ fluorescent assay. The levels of primary DNA damage in rat white blood cells were measured using the alkaline comet assay. The compound applied at 25% of its LD50 did not significantly affect ChE activity and lipid peroxidation and did not cause significant changes in the SOD activity in plasma. The cytotoxicity profile of K048 in the tested dose was also acceptable, and it did not possess significant DNA‐damaging potential. The obtained results are promising for further evaluations of the K048 oxime, which should include tests on a broader concentration range and longer incubation times.  相似文献   
100.
The differences in metal exposure (As, Cd, Cu, Pb and Hg) in the muscle, liver and kidney tissues of brown bears (Ursus arctos), grey wolfs (Canis lupus), Eurasian lynxs (Lynx lynx), Eurasian badgers (Meles meles) and pine martens (Martes martes) from Croatia were observed. The highest mean Cd levels were found in kidney and liver of Eurasian badger (3.05 and 0.537 mg/kg). The highest Cu concentrations (mg/kg) measured in liver tissue were obtained in order: Eurasian badger (15.2) > brown bear (12.1) > pine marten (10.3) > Eurasian lynx (8.43) > grey wolf (6.44). Result presented that Eurasian badger accumulated the highest levels of elements: As, Cu and Pb in muscle; As, Cd, Cu and Pb in liver; Cd and Pb in kidney. Kidney of pine marten accumulated the highest concentrations of As, Cu and Hg. Omnivorous species observed present an important bioindicator for the accumulation of toxic elements indicating an enhanced vulnerability for response to ecological changes in forested terrain. Generally, element concentrations found in five species observed were lower in comparison to levels reported in previous studies and below levels related to toxicosis in mammals.  相似文献   
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