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991.
Deb P Sharma MC Tripathi M Sarat Chandra P Gupta A Sarkar C 《Neuropathology and applied neurobiology》2006,32(5):461-468
The spectrum of glioneuronal lesions underlying intractable epilepsies includes malformative pathologies like focal cortical dysplasia (FCD); and neoplastic lesions like gangliogliomas (GG) and dysembryoplastic neuroepithelial tumours (DNT). These may occur either singly or as dual lesions, having simultaneous presence of both elements. Currently, the relationship between the malformative and neoplastic glioneuronal lesions is poorly understood. Recently, CD34, a stem cell marker transiently expressed during early neurulation, has been identified in these tumours. This study was undertaken to (i) evaluate the role of CD34 as a diagnostic marker for glioneuronal lesions of epilepsy, namely, GG, DNT and FCD, and (ii) attempt to define the relationship among these lesions, using CD34 as a marker. Tissues resected from 47 patients with intractable epilepsy due to glioneuronal lesions (GG, FCD, DNT) were studied. These were evaluated for CD34 expression, using immunohistochemistry. Dysplastic or atypically differentiated neural precursors which could not be identified on routine haematoxylin and eosin (H&E) staining were highlighted by CD34 immunostaining. The pattern of immunostaining was diffuse in GGs, unlike FCDs, wherein cells were present singly or in small clusters. However, cases of DNT and control tissue were largely CD34-immunonegative. Based on these findings, we propose a possible common origin of GG and FCD, from a bipotent precursor that undergoes abnormal glioneuronal development, while DNTs possibly have a different origin. The CD34-immunoreactive cells represent dysplastic or undifferentiated neural precursors, which may signify a valuable marker for the diagnostic evaluation of neoplastic and/or malformative pathologies in patients with intractable epilepsy. 相似文献
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Bettina Debû Clecio De Oliveira Godeiro Jarbas Correa Lino Elena Moro 《Current neurology and neuroscience reports》2018,18(5):23
Purpose of Review
Postural instability and gait difficulties inexorably worsen with Parkinson’s disease (PD) progression and become treatment resistant, with a severe impact on autonomy and quality of life. We review the main characteristics of balance instability, gait disabilities, and static postural alterations in advanced PD, and the available treatment strategies.Recent Findings
It remains very difficult to satisfactorily alleviate gait and postural disturbances in advanced PD. Medical and surgical interventions often fail to provide satisfactory or durable alleviation of these axial symptoms, that may actually call for differential treatments. Exercise and adapted physical activity programs can contribute to improving the patients’ condition.Summary
Gait, balance, and postural disabilities are often lumped together under the Postural Instability and Gait Difficulties umbrella term. This may lead to sub-optimal patients’ management as data suggest that postural, balance, and gait problems might depend on distinct underlying mechanisms. We advocate for a multidisciplinary approach from the day of diagnosis.996.
997.
Wiesemann E Deb M Hemmer B Radeke HH Windhagen A 《Clinical immunology (Orlando, Fla.)》2008,128(3):306-313
Interferon-beta (IFN-beta) is an effective treatment for a subgroup of patients with multiple sclerosis (MS). The mechanism of action as well as the pathophysiological basis of responsiveness to IFN-beta is not well understood. To improve treatment considerations in MS patients predictive markers for response to IFN-beta therapy at early timepoints are needed. Here we correlated changes in serum cytokine levels (IL-13, IL-10, IL-5, IL-4, IFN-gamma) with the clinical response to IFN-beta treatment. Serum cytokine levels of 77 untreated and 43 IFN-beta treated relapsing-remitting MS patients (RRMS) were measured by ELISA, including longitudinal measurements in 17 patients. We found a significant upregulation of IL-10 and IL-5 serum cytokine levels during IFN-beta therapy. However, clinical response was only associated with IL-10 serum levels (p=0.038; positive predictive value 0.95, negative predictive value 0.43) but not with IL-5. The predictive power was increased by a combined testing of IL-10 with expression of co-signaling molecules on monocytes, that were previously shown to change during IFN-beta therapy. In a subgroup of 17 patients testing of 4 markers had a positive and negative predictive value of 1.0 for at least 2 of these markers being positive in treatment responders. The results suggest that serum IL-10 is useful to predict treatment response to IFN-beta particularly in combination with a panel of other IFN-beta dependent parameters. 相似文献
998.
Micro-Raman analysis and AFM imaging of Acidithiobacillus ferrooxidans biofilm grown on uranium ore 总被引:1,自引:0,他引:1
Pradhan N Pradhan SK Nayak BB Mukherjee PS Sukla LB Mishra BK 《Research in microbiology》2008,159(7-8):557-561
Acidithiobacillus ferrooxidans biofilm grown on uranium ore substrate was analyzed by a micro-Raman spectrometer and an atomic force microscope (AFM). The bacterium employed for this study, A. ferrooxidans BM1, was isolated from a uranium mine (Jaduguda, India). Micro-Raman analysis revealed the different constituents of molecular fragments present in microbial cells and in secreted extracellular polymeric substances (EPSs). AFM images clearly revealed bacterial cells surrounded by EPS. From Raman spectral data, the composition of EPS from A. ferrooxidans BM1 appeared to be similar to that of EPS secreted in a different Pseudomonas bacterium. 相似文献
999.
The rat chorioallantoic placenta is comprised of two morphologically distinct regions: the junctional zone and the labyrinth zone. The purpose of this investigation was to determine the relative contributions of trophoblast cells in each of these regions to the expression of placental lactogen-II (PL-II) and PRL-like protein-A (PLP-A) during development, mRNA expression was estimated by Northern blot analysis, whereas, protein expression was estimated by electrophoresis, immunoblotting, and immunocytochemical analyses. The immunochemical analyses used antipeptide antisera directed to amino acids 56-70 of PL-II and amino acids 152-164 of PLP-A. Northern and immunoblotting analyses indicated that both PL-II mRNA and protein expression were maximal in the junctional zone on day 13 of gestation and declined as gestation proceeded. In contrast, PL-II mRNA and protein expression in the labyrinth zone were low on day 13 and increased as gestation advanced. PL-II was specifically localized to giant cells. At midgestation, PL-II-positive giant cells were identified bordering the uterine decidua in the junctional zone and choriovitelline placenta. As gestation advanced. PL-II-positive cells were also localized to the labyrinth zone. Immunoreactivity was restricted to the cytoplasm of PL-II-positive cells. PLP-A mRNA and protein were predominantly expressed in the junctional zone of the chorioallantoic placenta. Expression of PLP-A increased as gestation advanced. PLP-A was specifically localized to giant and spongiotrophoblast cells of the junctional zone. Immunoreactivity was found in both cytoplasmic and nuclear compartments of PLP-A-positive cells. In summary, PL-II expression shifts from the junctional to the labyrinth zone during pregnancy, whereas PLP-A is predominantly expressed in the junctional zone during the latter third of pregnancy. Both hormones are produced by giant cells of the junctional zone, but only PL-II is expressed by choriovitelline and labyrinthine trophoblast cells. PLP-A is also expressed by spongiotrophoblast cells of the junctional zone. These findings provide insights into the process of placental morphogenesis. 相似文献
1000.
An out break of acute bacillary dysentery in a village called Dhamasin in Hooghly district of West Bengal was investigated during March 1984. Forty seven percent of families were affected. A total of 91 cases and 2 deaths occurred amongst 937 people giving an over all attack rate of 9.7% and a case fatality rate of 2.2 percent. Highest attack rate (22.7%) was observed in below one year age group. Multiple drug resistant Shigella dysentery type 1 strains were isolated for the first time from 6 out of 22 cases sampled at the domiciliary level. The organism was never isolated earlier during last ten years of surveillance in the infectious Diseases Hospital, Calcutta. Identification of nature of this outbreak and it's causative agent helped to realise the potentiality of extensive spread and paved the way for further investigations. Public health authorities were buffled as the rapid spread of the disease throughout the entire state of West Bengal could not be contained in spite of instituting all probable control measures on war footing. 相似文献