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31.
目的:探讨双眼单视功能训练屈光性调节性内斜视(refractiveaccom-modativeesotropia,RAET)的效果。方法:收集70例屈光性调节性内斜视病例进行临床回顾性分析,评定疗效。主要在眼位变化,屈光状态变化、视力改变、双眼单视功能的变化方面进行分析,采用合理配戴眼镜6个月以上,治疗弱视或手术矫正眼位方法。结果:所有病例恢复正常眼位,70例中,有68例恢复双眼单视功能。结论:RAET经双眼单视功能训练能恢复眼位及双眼单视功能。 相似文献
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33.
BackgroundThe abnormal alcohol consumption could cause toxicity and could alter the human brain’s structure and function, termed as alcohol used disorder (AUD). Unfortunately, the conventional screening methods for AUD patients are subjective and manual. Hence, to perform automatic screening of AUD patients, objective methods are needed. The electroencephalographic (EEG) data have been utilized to study the differences of brain signals between alcoholics and healthy controls that could further developed as an automatic screening tool for alcoholics.MethodIn this work, resting-state EEG-derived features were utilized as input data to the proposed feature selection and classification method. The aim was to perform automatic classification of AUD patients and healthy controls. The validation of the proposed method involved real-EEG data acquired from 30 AUD patients and 30 age-matched healthy controls. The resting-state EEG-derived features such as synchronization likelihood (SL) were computed involving 19 scalp locations resulted into 513 features. Furthermore, the features were rank-ordered to select the most discriminant features involving a rank-based feature selection method according to a criterion, i.e., receiver operating characteristics (ROC). Consequently, a reduced set of most discriminant features was identified and utilized further during classification of AUD patients and healthy controls. In this study, three different classification models such as Support Vector Machine (SVM), Naïve Bayesian (NB), and Logistic Regression (LR) were used.ResultsThe study resulted into SVM classification accuracy = 98%, sensitivity = 99.9%, specificity = 95%, and f-measure = 0.97; LR classification accuracy = 91.7%, sensitivity = 86.66%, specificity = 96.6%, and f-measure = 0.90; NB classification accuracy = 93.6%, sensitivity = 100%, specificity = 87.9%, and f-measure = 0.95.ConclusionThe SL features could be utilized as objective markers to screen the AUD patients and healthy controls. 相似文献
34.
Concordance between 99mTc‐ECD SPECT and 18F‐FDG PET interpretations in patients with cognitive disorders diagnosed according to NIA‐AA criteria 下载免费PDF全文
35.
Marmol F 《Progress in neuro-psychopharmacology & biological psychiatry》2008,32(8):1761-1771
Bipolar illness is a major psychiatric disorder that affects 1-3% of the worldwide population. Epidemiological studies have demonstrated that this illness is substantially heritable. However, the genetic characteristics remain unknown and a clear personality has not been identified for these patients. The clinical history of lithium began in mid-19th century when it was used to treat gout. In 1940, it was used as a substitute for sodium chloride in hypertensive patients. However, it was then banned, as it had major side effects. In 1949, Cade reported that lithium could be used as an effective treatment for bipolar disorder and subsequent studies confirmed this effect. Over the years, different authors have proposed many biochemical and biological effects of lithium in the brain. In this review, the main mechanisms of lithium action are summarised, including ion dysregulation; effects on neurotransmitter signalling; the interaction of lithium with the adenylyl cyclase system; inositol phosphate and protein kinase C signalling; and possible effects on arachidonic acid metabolism. However, none of the above mechanisms are definitive, and sometimes results have been contradictory. Recent advances in cellular and molecular biology have reported that lithium may represent an effective therapeutic strategy for treating neurodegenerative disorders like Alzheimer's disease, due to its effects on neuroprotective proteins like Bcl-2 and its actions on regulators of apoptosis and cellular resilience, such as GSK-3. However, results are contradictory and more specific studies into the use of lithium in therapeutic approaches for neurodegenerative diseases are required. 相似文献
36.
The present study was carried out to investigate the effects of catechin on adjuvant arthritis (AA) in the rat and its possible
mechanisms of action. AA was induced by metatarsal footpad injection with complete Freund’s adjuvant in male Sprague-Dawley
rats. The secondary inflammatory reaction was evaluated through assessment of hind paw swelling, polyarthritis index, and
pain response. Proliferation of synoviocytes and the activity of interleukin-1 were examined by 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium
bromide assay. Tumor necrosis factor-α, prostaglandin E2 (PGE2), and cyclic adenosine monophosphate levels in synoviocytes were measured by radioimmunoassay. The PGE2 receptor, EP2, was analyzed by Western blot analysis. Intragastric administration of catechin (60 and 120 mg/kg) significantly suppressed
secondary inflammatory paw swelling, pain response, and polyarthritis index. It also inhibited production of interleukin-1,
tumor necrosis factor-α, and PGE2 and increased cyclic adenosine monophosphate levels in rats with AA. In the immunoblot analysis, catechin could upregulate
expression of EP2 in the synoviocytes of rats with AA. The results showed that catechin reduced secondary inflammation in rats with AA; this
outcome reflects its ability to mediate cAMP levels, upregulate expression of EP2, and inhibit secretion of proinflammatory cytokines in rats with AA. 相似文献
37.
《Placenta》2017
Preeclampsia (PE) was shown to affect the placental content and the transfer of polyunsaturated fatty acids (PUFA) to the fetus. Plasmalogens, a type of phospholipids with a vinyl-ether link at the sn-1 position, play an antioxidant role and are specifically enriched in PUFA at the sn-2 position. In this study, we characterized plasmalogen-derived dimethyl acetal (DMA) fatty acid derivatives, 16:0 DMA, 18:0 DMA, 9c-/11c-18:1 DMA and PUFA in the placenta of normotensive (n = 20) and PE (n = 20) pregnancies, according to the sampling site: peri-insertion or periphery. Phospholipid fatty acids from the placenta and maternal erythrocytes were identified by gas chromatography mass spectrometry and quantified by flame ionization detection. We found elevated total DMA in the PE placenta by 18% when compared to normotensive controls (p = 0.026). Moreover, the 16:0 DMA account for more than 55% of DMA fatty acids measured in the placenta, and its level is significantly higher in PE than controls (p = 0.018). Also, we found elevated placental PUFA, 20:5(n-3), 22:5(n-3) and a low level of 20:4(n-3) in PE compared to controls. Placental DMA was highly correlated with n-6 and n-3 PUFA in both, normotensive and PE pregnancies. In sum, elevated DMA fatty acids in the PE placenta could be an indirect defensive mechanism against oxidative stress and poor placental fatty acid transfer in PE. 相似文献
38.
Martinez-Marcos A 《Progress in neurobiology》2009,87(1):21-30
Classically, the olfactory and vomeronasal pathways are thought to run in parallel non-overlapping axes in the forebrain subserving different functions. The olfactory and vomeronasal epithelia project to the main and accessory olfactory bulbs (primary projections), which in turn project to different areas of the telencephalon in a non-topographic fashion (secondary projections) and so on (tertiary projections). New data indicate that projections arising from the main and accessory olfactory bulbs converge widely in the rostral basal telencephalon. In contrast, in the vomeronasal system, cloning two classes of vomeronasal receptors (V1R and V2R) has led to the distinction of two anatomically and functionally independent pathways that reach some common, but also some different, targets in the amygdala. Tertiary projections from the olfactory and vomeronasal amygdalae are directed to the ventral striatum, which thus becomes a site for processing and potential convergence of chemosensory stimuli. Functional data indicate that the olfactory and vomeronasal systems are able to detect and process volatiles (presumptive olfactory cues) as well as pheromones in both epithelia and bulbs. Collectively, these data indicate that the anatomical and functional distinction between the olfactory and vomeronasal systems should be re-evaluated. Specifically, the recipient cortex should be reorganized to include olfactory, vomeronasal (convergent and V1R and V2R specific areas) and mixed (olfactory and vomeronasal) chemosensory cortices. This new perspective could help to unravel olfactory and vomeronasal interactions in behavioral paradigms. 相似文献
39.
Eighteen renal biopsy specimens obtained from patients with AA-type renal amyloidosis (AA) and 11 from patients with AL-type renal amyloidosis (AL), for whom both light and electron microscopy as well as immunofluorescence microscopy and full clinical data were available, were examined quantitatively. The cases were selected on the basis of immunohistochemical studies. As a control, we used 10 biopsy specimens from the kidneys removed because of trauma. Morphometric investigations were carried out by a computer image analysis system to find an answer to the question of whether mast cells can correlate with tubulointerstitial fibrosis in AA and AL renal amyloidosis, and to examine the relationship between mast cells and interstitial alpha-smooth muscle actin (alpha-SMA) expression and interstitial infiltrates. The morphometric study revealed that the mean values of the interstitial tryptase-positive cells, expression of alpha-SMA, interstitial volume, CD68+, CD45RB+, CD43+ and CD20+ cells were increased in AA as compared with the AL group, most of them significantly. Most of these parameters were also significantly increased in both AA and AL patients as compared with the control group. In both the AA group and the AL group, there existed some significant positive correlations between interstitial tryptase-positive cells and interstitial expression of alpha-SMA, interstitial volume and CD68+ cells. Interestingly, in AA cases, but not in AL cases, we noted a significant relationship between interstitial tryptase-positive cells and CD43+ cells. Our findings demonstrate that mast cells belong to the constitutive cell types in the interstitium in renal amyloidosis, in particular in amyloid type A. In addition, in both the AA group and the AL group, the significant positive correlations between interstitial mast cell count and relative interstitial volume and interstitial expression of alpha-SMA suggest that these cells play a role in the development of interstitial fibrosis. 相似文献
40.
Szwergold BS 《Medical hypotheses》2007,68(1):37-45
Nonenzymatic glycation of proteins and some phospholipids by glucose and other reducing sugars (a.k.a Maillard reaction) is an unavoidable result of the coexistence of these sugars and the affected macromolecules in living systems. The consequences of this process are deleterious both in the intracellular and extracellular environments as evidenced by the close association between increased nonenzymatic glycation and complications of diabetes. Because of these considerations, we have proposed that the intrinsic toxicity of glucose and other sugars is counteracted in vivo by active deglycation mechanisms including transglycation of Schiff's bases and FN3K-dependent breakdown of fructosamines. While this modified hypothesis is receiving increasing experimental support, several issues regarding glycation/deglycation remain unresolved. Two such important questions are In this paper we propose a resolution of both these quandaries by proposing that fructosamine-6-phosphates are deglycated by phosphorylation to fructosamine-3,6-bisphosphates catalyzed by FN3KRP and/or possibly FN3K. We provide some preliminary evidence in support of this hypothesis and outline experimental approaches for definitive tests of this hypothesis. The potential medical implications of this finding are not clear yet but, if correct, this observation is likely to have a major impact on our understanding of the very basic and hitherto unexplored aspect of glucose metabolism and chemistry in vivo. One can imagine that, at some point in the future, measurement of FN3K/FN3KRP activity may be of diagnostic value in assessing an individual's susceptibility to diabetic complications. Further down the road, one can also envision a gene therapeutic intervention to bolster FN3K/FN3KRP-based antiglycation defenses. 相似文献