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961.
Uveal melanoma (UM) exhibits recurring chromosomal abnormalities and gene driver mutations, which are related to tumor evolution/progression. Almost half of the patients with UM develop distant metastases, predominantly to the liver, and so far there are no effective adjuvant therapies. An accurate UM genetic profile could assess the individual patient's metastatic risk, and provide the basis to determine an individualized targeted therapeutic strategy for each UM patient. To investigate the presence of specific chromosomal and gene alterations, BAP1 protein expression, and their relationship with distant progression free survival (DPFS), we analyzed tumor samples from 63 UM patients (40 men and 23 women, with a median age of 64 years), who underwent eye enucleation by a single cancer ophthalmologist from December 2005 to June 2016. UM samples were screened for the presence of losses/gains in chromosomes 1p, 3, 6p, and 8q, and for mutations in GNAQ, GNA11, BAP1, SF3B1, and EIF1AX. BAP1 protein expression was detected by immunohistochemistry (IHC). Multivariate analysis showed that the presence of monosomy 3, 8q gain, and loss of BAP1 protein were significantly associated to DPFS, while BAP1 gene mutation was not, mainly due to the presence of metastatic UM cases with negative BAP1 IHC and no BAP1 mutation detected by Sanger sequencing. Loss of BAP1 protein expression and monosomy 3 represent the strongest predictors of metastases, and may have important implications for implementation of patient surveillance, properly designed clinical trials enrollment, and adjuvant therapy.  相似文献   
962.
Oncolytic adenoviral immunotherapy activates the innate immune system with subsequent induction of adaptive tumor‐specific immune responses to fight cancer. Hence, oncolytic viruses do not only eradicate cancer cells by direct lysis, but also generate antitumor immune response, allowing for long‐lasting cancer control and tumor reduction. Their therapeutic effect can be further enhanced by arming the oncolytic adenovirus with costimulatory transgenes and/or coadministration with other antitumor therapies. ONCOS‐102 has already been found to be well tolerated and efficacious against some types of treatment‐refractory tumors, including mesothelin‐positive ovarian cancer (NCT01598129). It induced local and systemic CD8+ T‐cell immunity and upregulated programmed death ligand 1. These results strongly advocate the use of ONCOS‐102 in combination with other therapeutic strategies in advanced and refractory tumors, especially those expressing the mesothelin antigen. The in vivo work presented herein describes the ability of the oncolytic adenovirus ONCOS‐102 to induce mesothelin‐specific T‐cells after the administration of the virus in bagg albino (BALB/c) mice with mesothelin‐positive tumors. We also demonstrate the effectiveness of the interferon‐γ the enzyme‐linked immunospot (ELISPOT) assay to detect the induction of T‐cells recognizing mesothelin, hexon, and E1A antigens in ONCOS‐102‐treated mesothelioma‐bearing BALB/c mice. Thus, the ELISPOT assay could be useful to monitor the progress of therapy with ONCOS‐102.  相似文献   
963.
We previously demonstrated a high susceptibility of neonatal red blood cells (RBC) to oxidative stress at birth. The aim of this study was to compare the RBC antioxidant capacity and redox cycle enzyme activities as well as glutathione (GSH) recycling in full-term and preterm infants at birth and in normal adults. GSH and GSH disulfide (GSSG) concentrations, GSH/GSSG ratio, and the activities of glucose-6-phosphate dehydrogenase (G-6-PDH), GSH peroxidase, GSH reductase (GR), catalase (CAT), superoxide dismutase (SOD), and hexokinase (HK) were measured in RBC of 25 healthy adults and 56 newborns (23 term, 33 preterm) at birth. The GSH recycling was measured in adult and newborn RBC exposed to oxidative stress (1 mM tert-butylhydroperoxide). The RBC of term and preterm babies showed higher GSH, GSSG, G-6-PDH, GR, and HK levels/activities and lower GSH/GSSG ratios and higher GSH-recycling rates than those of adults. In preterm babies significant correlations were found between G-6-PDH and CAT, GSH, GSH/GSSG ratio, and GSSG (r = -0.67, r = 0.71, r = -0.66, p < 0.01; r = 0.71, p < 0.05, respectively). In term newborns, statistically significant correlations were observed between G-6-PDH and CAT, SOD, and GSH (r = -0.65, r = -0.65, r = -0.69, p < 0.01, respectively). The results indicate the central role of the G-6-PDH activity in antioxidant defenses. We speculate that preterm babies have prompter involvement of antioxidant defenses than term babies.  相似文献   
964.
OBJECTIVES: To assess the risk of fetal loss attributable to second trimester amniocentesis in singleton pregnancies through a cross-sectional study. METHODS: Records of 5043 consecutive second trimester amniocentesis, performed by a single operator between 1997 and 2003, were analyzed. Fetal loss post amniocentesis was calculated by grouping pregnant women in age classes and assessing observed/expected (O/E) rate. RESULTS: Total fetal losses were 40 (0.81%): 33 cases (0.67%) occurred before the 24th week, 37 cases (0.76%) before the 28th gestational week, and 3 cases (0.06%) after the 28th week of pregnancy. An age-dependent increase of the rate of fetal loss, not statistically significant (Chi-Square = 0.349, p = 0.505) was observed. The total O/E ratio values did not show any statistically significant risk (O/E ratio = 1.25, CI = 0.86-1.64). The analysis of the single age classes did not detect any statistical significance. The excess fetal loss rate associated with amniocentesis was 0.16%. CONCLUSIONS: No effect of the 2nd trimester amniocentesis was noted on fetal loss.  相似文献   
965.
BACKGROUND: CXCL8/IL-8 is the most significant chemokine for neutrophils, and CXC chemokine receptor (CXCR) 1 and 2 are its 2 receptors, which are downmodulated by CXCL8/IL-8 and endotoxin on activated neutrophils. OBJECTIVE: We sought to evaluate the expression of the CXCL8/IL-8 receptors and the activation marker CD11b on neutrophils in peripheral blood and in the site of airway inflammation. METHODS: The flow cytometric expression of CXCR1, CXCR2, and CD11b was evaluated on peripheral blood and induced sputum neutrophils in patients with nonsevere asthma with greater than 60% sputum neutrophils, in patients with chronic obstructive pulmonary disease (COPD), and in healthy control subjects. RESULTS: Asthmatic patients and patients with COPD had comparable expressions of CXCR1, CXCR2, and CD11b on peripheral blood and sputum neutrophils. Compared with control subjects, the peripheral neutrophil expression of CXCR2 was lower in patients with COPD ( P = .03) and that of CD11b was higher in asthmatic patients and patients with COPD ( P < .02 and P < .002). The expression of the CXCL8/IL-8 receptors on sputum neutrophils was markedly lower than on peripheral blood neutrophils ( P < .0001). The downmodulation of CXCL8/IL-8 receptors was also present in healthy control subjects but less than that seen in asthmatic patients. The difference between peripheral blood and sputum expression of CXCL8/IL-8 receptors correlated with serum CXCL8/IL-8 levels. In asthmatic patients the expression of CXCR1 and CXCR2 on sputum neutrophils negatively correlated with sputum neutrophils. CONCLUSION: In neutrophilic asthma the expression of CXCL8/IL-8 receptors on peripheral and sputum neutrophils is similar to COPD and negatively correlated with the inflammatory infiltrate in the airways. The downmodulation of CXCL8/IL-8 receptors detected in the airways should be taken into account for an eventual therapeutic inhibition of these receptors.  相似文献   
966.
967.
Cultured HeLa cells were irradiated with a single acute dose of either gamma rays (40 Gy) or low‐energy proton beams (20 Gy). 1H magnetic resonance spectra of intact cells harvested at different times after irradiation and of the correspondent perchloric acid (PCA) extracts prepared at different times after irradiation were run. Selected signals from glutathione and lactate were examined with the aim of investigating effects of irradiation on antioxidative stores and on mitochondrial activity. An increase of signal intensity of glutathione (GSH) takes place at 15 and 24 hr after irradiation, while a decrease of its signal intensity, accompanied by an increase of that of free glutamate, starts appearing 48 hr after irradiation. Lactate signal increases 48 hr after irradiation. Signals from lipid catabolites were also examined to explore their sensitivity in predicting the response to radiotherapy. Intensity ratios of signals of glycerophosphorylcholine and choline to that of phosphorylcholine increase with time after irradiation. Irradiating cells with gamma rays or proton beams at half a dose produces effects comparable to the metabolic variations presented here. The present experiments allow more insight into the complex pattern of the changes of GSH by irradiation and indicate that magnetic resonance spectroscopy signals from GSH, glutamate, lactate, and lipid catabolites are affected by irradiation. Finally, these data represent a first indication that the relative biological efficiency for some metabolic damage of low‐energy proton beams with respect to gamma rays can reach a value of 2. © 2002 Wiley‐Liss, Inc.  相似文献   
968.
969.
OBJECTIVE: Congenital optic nerve head coloboma represents an important cause of childhood visual impairment and blindness; it can be isolated or, more often, it can be associated with several syndromes. Ultrasound has limitations in depicting the posterior aspect of the fetal eye globe, so prenatal information about ocular coloboma are very scarce. The purpose of this paper was to report prenatal magnetic resonance (MR) imaging features of optic nerve head coloboma. METHODS: MR imaging at 1.5 Tesla was based on multiplanar single-shot fast spin-echo T2-weighted 3-4 mm thick contiguous sections. RESULTS: Three fetal cases with optic nerve head coloboma and one with microphthalmos and colobomatous cyst are reported. Coloboma appeared as a focal bulging of ocular globe profile at the insertion of optic nerve. CONCLUSION: Prenatal MR imaging allowed an accurate diagnosis to be obtained.  相似文献   
970.
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