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61.
do Lago Eliel Scarpioni Ferreira Sabrina Garcia Idelmo Rangel Okamoto Roberta Mariano Ronaldo Clio 《Clinical oral investigations》2020,24(5):1637-1650
Clinical Oral Investigations - The effect of leucocyte- and platelet-rich fibrin (L-PRF), associated with DBBM (deproteinized bovine bone mineral; Bio-Oss®) was investigated and compared with... 相似文献
62.
Expression of angiopoietin‐like protein 4 at the fracture site: Regulation by hypoxia and osteoblastic differentiation 下载免费PDF全文
Sabrina S. Wilson Alice Wong Chrisoula A. Toupadakis Clare E. Yellowley 《Journal of orthopaedic research》2015,33(9):1364-1373
Vascular disruption that occurs as a consequence of bone fracture, leads to hypoxia at the site of damage. Hypoxia regulates the expression of a number of genes that can modulate energy conservation, cell survival, tissue regeneration and angiogenesis. In this study we investigated the expression of Angiopoietin‐like 4, an adipocytokine that has additional roles in angiogenesis, at the fracture site. We demonstrate that Angptl4 mRNA expression increased early during fracture healing (day 3) returning close to baseline at day14. In the callus, Angptl4 mRNA was visualized in areas of condensing mesenchymal cells, callus cartilage and was especially high in mineralizing osteoblasts located in areas of new bone formation. In vitro, Angptl4 mRNA expression in osteoblasts increased under hypoxic conditions and in cells treated with the hypoxia mimetic desferrioxamine. Angptl4 levels were strongly induced at day 14 in differentiating MC3T3‐E1 osteoblastic cells. Exogenous ANGPTL4 increased expression of Runx2, Spp1, vegfa, and Alp mRNA in differentiating osteoblasts. We suggest that the distribution of Angptl4 in the callus may be driven by hypoxia and that Angptl4 may play a role in osteoblastic differentiation, and possibly angiogenesis via regulation of VEGF. Further studies could reveal a dual role for Angptl4 in angiogenesis and osteogenesis. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1364–1373, 2015. 相似文献
63.
Chiara Bozzacchi Donatella Spinelli Sabrina Pitzalis Maria Assunta Giusti Francesco Di Russo 《Social cognitive and affective neuroscience》2015,10(6):783-789
Literature on mirror neurons has shown that seeing someone preparing to move generates in the motor areas of the observers a brain activity similar to that generated when the subject prepares his own actions. Thus, the ‘mirroring’ of action would not be limited to the execution phase but also involves the preparation process. Here we confirm and extend this notion showing that, just as different brain activities prepare different voluntary actions, also different brain activities prepare to observe different predictable actions. Videos of two different actions from egocentric point of view were presented in separate blocks: (i) grasping of a cup and (ii) impossible grasping of a cup. Subjects had to passively observe the videos showing object-directed hand movements. Through the use of the event-related potentials, we found a cortical activity before observing the actions, which was very similar to the one recorded prior to the actual execution of that same action, in terms of both topography and latency. This anticipatory activity does not represent a general preparation state but an action-specific state, because being dependent on the specific meaning of the forthcoming action. These results reinforce our knowledge about the correspondence between action, perception and cognition. 相似文献
64.
Amplified C lambda and c-abl genes are on the same marker chromosome in K562 leukemia cells. 总被引:16,自引:6,他引:16 下载免费PDF全文
J R Selden B S Emanuel E Wang L Cannizzaro A Palumbo J Erikson P C Nowell G Rovera C M Croce 《Proceedings of the National Academy of Sciences of the United States of America》1983,80(23):7289-7292
The human leukemia cell line K562, derived from a patient with Philadelphia chromosome-positive chronic myelogenous leukemia, contains amplified c-abl oncogenes and unrearranged C lambda genes. Using in situ hybridization techniques, we have determined that the amplified c-abl and C lambda DNA sequences of K562 cells are both located on the same abnormal acrocentric marker chromosome, which may represent an altered Philadelphia chromosome. 相似文献
65.
Reactivation of silent rRNA genes by simian virus 40 in human-mouse hybrid cells. 总被引:21,自引:4,他引:21 下载免费PDF全文
K J Soprano V G Dev C M Croce R Baserga 《Proceedings of the National Academy of Sciences of the United States of America》1979,76(8):3885-3889
Mouse-human hybrid cells were used to study the ability of simian virus 40 to regulate the expression of rRNA genes in vivo. In these hybrid cells, only the rRNA genes of the dominant species are expressed; the genes for the rRNA of the recessive species are silent. Simian virus 40 infection of these hybrids led to the production of two distinct 28S rRNA species as analyzed by agarose/2.4% polyacrylamide gel electrophoresis. These species were identified as human and mouse rRNAs. This result was confirmed by histochemical studies which indicated that the nucleolus organizer regions of both mouse and human chromosomes were actively synthesizing rRNA in the virus-infected hybrid cells. These results indicate that simian virus 40 infection can induce the expression of otherwise silent rRNA genes. 相似文献
66.
Gasco V Corneli G Rovere S Croce C Beccuti G Mainolfi A Grottoli S Aimaretti G Ghigo E 《Pituitary》2008,11(2):121-128
Based on previous consensus statements, it has been widely accepted that the diagnosis of adult growth hormone deficiency
(GHD) must be shown biochemically by provocative tests of GH secretion; in fact, the measurement of IGF-I as well as of other
markers was considered unable to distinguish between normal and GHD subjects. The Insulin Tolerance Test (ITT) was indicated
as that of choice and severe GHD defined by a GH peak lower than 3 μg/l. It is now recognized that, although normal IGF-I
levels do not rule out severe GHD, very low IGF-I levels in patients highly suspected for GHD (i.e. patients with childhood-onset
severe GHD or with multiple hypopituitarism acquired in adulthood) can be considered as definite evidence for severe GHD.
However, patients suspected for adult GHD with normal IGF-I levels must be investigated by provocative tests. ITT remains
a test of reference but it should be recognized that other tests are as reliable as ITT. Glucagon as classical test and, particularly,
new maximal tests such as GHRH in combination with arginine or GH secretagogues (GHS) (i.e. GHRP-6) have well defined cut-off
limits, are reproducible, able to distinguish between normal and GHD subjects. Overweight and obesity have confounding effect
on the interpretation of the GH response to provocative tests. In adults cut-off levels of GH response below which severe
GHD is demonstrated must be appropriate to lean, overweight and obese subjects to avoid false positive diagnosis in obese
adults and false negative diagnosis in lean GHD patients. 相似文献
67.
Anja K. Büscher Bodo B. Beck Anette Melk Julia Hoefele Birgitta Kranz Daniel Bamborschke Sabrina Baig B?rbel Lange-Sperandio Theresa Jungraithmayr Lutz T. Weber Markus J. Kemper Burkhard T?nshoff Peter F. Hoyer Martin Konrad Stefanie Weber 《Clinical journal of the American Society of Nephrology》2016,11(2):245-253
Background and objectives
Treatment of congenital nephrotic syndrome (CNS) and steroid–resistant nephrotic syndrome (SRNS) is demanding, and renal prognosis is poor. Numerous causative gene mutations have been identified in SRNS that affect the renal podocyte. In the era of high–throughput sequencing techniques, patients with nongenetic SRNS frequently escape the scientific interest. We here present the long-term data of the German CNS/SRNS Follow-Up Study, focusing on the response to cyclosporin A (CsA) in patients with nongenetic versus genetic disease.Design, setting, participants, & measurements
Cross–sectional and longitudinal clinical data were collected from 231 patients with CNS/SRNS treated at eight university pediatric nephrology units with a median observation time of 113 months (interquartile range, 50–178). Genotyping was performed systematically in all patients.Results
The overall mutation detection rate was high at 57% (97% in CNS and 41% in SRNS); 85% of all mutations were identified by the analysis of three single genes only (NPHS1, NPHS2, and WT1), accounting for 92% of all mutations in patients with CNS and 79% of all mutations in patients with SRNS. Remission of the disease in nongenetic SRNS was observed in 78% of patients after a median treatment period of 2.5 months; 82% of nongenetic patients responded within 6 months of therapy, and 98% of patients with nongenetic SRNS and CsA–induced complete remission (normalbuminemia and no proteinuria) maintained a normal renal function. Genetic SRNS, on the contrary, is associated with a high rate of ESRD in 66% of patients. Only 3% of patients with genetic SRNS experienced a complete remission and 16% of patients with genetic SRNS experienced a partial remission after CsA therapy.Conclusions
The efficacy of CsA is high in nonhereditary SRNS, with an excellent prognosis of renal function in the large majority of patients. CsA should be given for a minimum period of 6 months in these patients with nongenetic SRNS. In genetic SRNS, response to CsA was low and restricted to exceptional patients. 相似文献68.
69.
70.
Access of Elderly Adults to Potentially Inappropriate Medications in the Brazilian Health System 下载免费PDF全文