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101.
102.
目的探讨在职腹膜透析患者的主要心理压力源,帮助护理人员为患者提供个体化护理干预。方法采用现象学研究方法,选择2016年3—4月于海军军医大学附属长征医院行腹膜透析的在职患者20例,以半结构式的深入访谈收集资料,运用Nvivo 7.0定性资料辅助分析软件及Colaizzi现象分析法对访谈资料进行整理和分析。结果在职腹膜透析患者的压力源主要包括疾病对回归工作的影响;个人角色冲突与失衡;职业发展与现实存在矛盾;期盼社会支持和心理认同感。结论在职腹膜透析患者在多方面承受着巨大的精神压力,存在生理、心理双重的不良体验。护士应根据患者的压力来源,采取有效措施缓解其压力。  相似文献   
103.
Abstract

Recent reports support the possible role of PI3K in sperm capacitation and acrosome reaction, although studies regarding PI3K identity in human sperm, under certain disease states such as varicocele, are still lacking. The authors, therefore, examined the expression profile and ultrastructural localization of PI3K in human semen samples, comparing healthy donors and patients with varicocele. The results obtained performing western blotting assay showed decreased PI3K expression in varicocele with respect to the “healthy” sperm. Immunogold labeling revealed human sperm cellular compartments containing PI3K, evidencing it in the head at both the membrane and nucleus and the entire tail, from the middle to the end piece of normal sperm. In varicocele PI3K label was confined to the head, with a strong reduction of specific reaction in the neck, middle piece, and tail. In conclusion, the data suggest that PI3K may play a role in the maintenance of male factor infertility associated with varicocele, and it may be further exploited as an additional molecular marker for the diagnosis of male infertility disorders.  相似文献   
104.
Pain arises from the integration of sensory and cognitive processes in the brain, resulting in specific patterns of neural oscillations that can be characterized by measuring electrical brain activity. Current source density (CSD) estimation from low‐resolution brain electromagnetic tomography (LORETA) and its standardized (sLORETA) and exact (eLORETA) variants, is a common approach to identify the spatiotemporal dynamics of the brain sources in physiological and pathological pain‐related conditions. However, there is no consensus on the magnitude and variability of clinically or experimentally relevant effects for CSD estimations. Here, we systematically examined reports of sample size calculations and effect size estimations in all studies that included the keywords pain, and LORETA, sLORETA, or eLORETA in Scopus and PubMed. We also assessed the reliability of LORETA CSD estimations during non‐painful and painful conditions to estimate hypothetical sample sizes for future experiments using CSD estimations. We found that none of the studies included in the systematic review reported sample size calculations, and less than 20% reported measures of central tendency and dispersion, which are necessary to estimate effect sizes. Based on these data and our experimental results, we determined that sample sizes commonly used in pain studies using CSD estimations are suitable to detect medium and large effect sizes in crossover designs and only large effects in parallel designs. These results provide a comprehensive summary of the effect sizes observed using LORETA in pain research, and this information can be used by clinicians and researchers to improve settings and designs of future pain studies.  相似文献   
105.
106.
《Clinical neurophysiology》2021,132(2):568-580
ObjectiveFast Oscillations (FO) >40 Hz are a promising biomarker of the epileptogenic zone (EZ). Evidence using scalp electroencephalography (EEG) remains scarce. We assessed if electrical source imaging of FO using 256-channel high-density EEG (HD-EEG) is useful for EZ identification.MethodsWe analyzed HD-EEG recordings of 10 focal drug-resistant epilepsy patients with seizure-free postsurgical outcome. We marked FO candidate events at the time of epileptic spikes and verified them by screening for an isolated peak in the time-frequency plot. We performed electrical source imaging of spikes and FO within the Maximum Entropy of the Mean framework. Source localization maps were validated against the surgical cavity.ResultsWe identified FO in five out of 10 patients who had a superficial or intermediate deep generator. The maximum of the FO maps was localized inside the cavity in all patients (100%). Analysis with a reduced electrode coverage using the 10–10 and 10–20 system showed a decreased localization accuracy of 60% and 40% respectively.ConclusionsFO recorded with HD-EEG localize the EZ. HD-EEG is better suited to detect and localize FO than conventional EEG approaches.SignificanceThis study acts as proof-of-concept that FO localization using 256-channel HD-EEG is a viable marker of the EZ.  相似文献   
107.
108.
There is an interest in the nuclear degraded sperm subpopulation because, although it is present in a low percentage in all semen samples, patient groups such as varicocele and rearranged genome carriers show high levels of these degraded spermatozoa. This study is designed with two objectives in mind: first, incubations of H2O2 and nuclease on DTT‐treated and untreated samples to show the aetiology of this subpopulation and second, assessment of the correlation between the protamine ratio and nuclear degraded spermatozoa. A very high increase in the nuclear degraded subpopulation has been found with nuclease incubation, and it is even higher when it has been merged with nuclear decompaction using DTT. Alternatively, incubation with H2O2 with and without DTT did not show such a significant increase in nuclear degraded spermatozoa. The protamine ratio correlated with this subpopulation, showing, in patients, that poor nuclear compaction would turn the sperm susceptible to degradation. Then, the assessment of nuclear degraded spermatozoa might not be only a measure of DNA degradation but also an indicator of chromatin compaction in the spermatozoa. Different patient groups would fit this model for sperm nuclear degradation, such as varicocele patients, who show a high percentage of immature spermatozoa and nuclear degraded spermatozoa, and reorganised genome carriers, where reorganisation might also cause poor chromatin compaction on the sperm nucleus.  相似文献   
109.
C. Uguz  O. Varisli  C. Agca  T. Evans  Y. Agca 《Andrologia》2015,47(8):910-919
The objective of this study was to determine the effects of nonylphenol (NP) on viability of ram and boar sperm in vitro. Ram or boar spermatozoa were exposed to 1, 10, 100, 250 and 500 μg NP ml?1 for 1, 2, 3 or 4 h. Computer‐assisted sperm motility analysis (CASA) system was used to evaluate sperm motility characteristics. Flow cytometry was used to determine mitochondrial membrane potential (MMP) and chromatin integrity, while epifluorescent microscopy was used to determine sperm acrosomal status. Exposure of both species spermatozoa to 250 and 500 μg NP ml?1 was detrimental to progressive motility (P < 0.05), and its adverse effect was significant at lower (100 μg NP ml?1) concentration (P < 0.05). The percentages of ram and boar spermatozoa with high MMP declined drastically after exposures to ≥250 μg ml?1 NP (P < 0.05). Unlike chromatin integrity, which did not appear to be altered by NP exposure, there were dose‐dependent NP effects (P < 0.05) on acrosomal integrity of both species at as low as 1 μg ml?1 NP for boar spermatozoa and 10 μg ml?1 NP for ram spermatozoa. These data show adverse effects of NP on ram and boar spermatozoa and thus its potential harmful effects on male reproduction as NP is found in fruits, vegetables, human milk, fish and livestock products.  相似文献   
110.
This study was designed to find out Ruta graveolens L. functional components, which have immobilisation effect on human spermatozoa for contraceptive use. A five‐step fractionation method was used to derive different components from rue aqueous extract by using hexane, chloroform, ethanol, acetone and ultrapure water. Gas chromatography–mass spectrophotometery (GC–MS) of all fractions and the aqueous extract were performed to determine the chemical components. The immobilisation assay and membrane integrity test were also performed with four different coumarins, which were found in GC–MS in a concentration of 10 μm . Hexane, chloroform, acetone and ethanol fractions could significantly decrease motility of sperms within the first and the second hours. Hexane fraction had also significant immediate effect. The aqueous fraction had no effect on sperm motility. Meanwhile, GC–MS revealed that aqueous extract and effective fractions had similar coumarin compounds. We performed the immobilisation assay on four different coumarins, which were found in GC–MS in a concentration of 10 μm . Reduction of sperm motility was only significant for xanthotoxin. In the sperm viability and membrane integrity tests, hexane and ethanolic fractions could impair sperm vitality significantly, in contrast to coumarins. These results indicated that a part of immobilising effect of rue could be due to its coumarins. The possible mechanism could be blocking of spermatozoa potassium channels.  相似文献   
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