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981.
Goldman G Baldet P David S Khouri K Fertit HE Costes V Rigau V 《Annales de pathologie》2011,31(4):236-241
The authors expose the clinical, radiological and histological presentation of three cases of solitary fibrous tumors of the meninges, initially thought to be meningiomas. Actually, these three cases show typical anatomoclinical features. The authors also mention the differential diagnosis, and recall the essential contribution of immunohistochemistry. 相似文献
982.
Hamdy NM Al-Abbasi FA Alghamdi HA Tolba MF Esmat A Abdel-Naim AB 《Toxicology letters》2012,208(2):108-114
Acrylonitrile (ACN) is a widely used intermediate in the manufacture of plastics, acrylic ?bers, synthetic rubbers and resins that are used in a variety of products including food containers and medical devices. ACN is a possible human carcinogen and a documented animal carcinogen, with the stomach being an important target of its toxicity. ACN has been previously reported to require metabolic activation to reactive intermediates and finally to cyanide (CN−). The current study aimed at exploring the potential role of neutrophils in ACN-induced gastric damage in rats. Experimental neutropenia was attained by injecting rats with methotrexate. This significantly ameliorated gastric mucosal injury induced by ACN. This is evidenced by protection against the increase in gastric ulcer index, myeloperoxidase (MPO) activity and CN− level. Also, neutropenia guarded against the decrease in prostaglandin E2 (PGE2), induction of oxidative stress and reduction of total nitrites and alleviated histopathological alterations in rat stomachs. These data indicate that neutrophil infiltration is, at least partly, involved in ACN-induced gastric damage in rats. 相似文献
983.
984.
ABSTRACT: Investigation of the aerial parts of the Egyptian medicinal plant Ammi majus L. led to isolation of new coumarin, 6-hydroxy-7-methoxy-4 methyl coumarin (2) and 6-hydroxy-7-methoxy coumarin (3); this is the first time they have been isolated from this plant. The structures of the compounds (2 &3) were elucidated by spectroscopic data interpretation and showed anti-inflammatory and anti-viral activity. GRAPHICAL ABSTRACT: An efficient, one-new coumarin (2) was isolated from the aerial parts of the A. Majus L. was evaluated for their anti-viral and anti-inflammatory activities. 相似文献
985.
Using an anti-cue keypress task, we examined executive control in Parkinson's disease (PD) patients treated with deep brain stimulation (DBS) of the subthalamic nucleus (STN) and dopaminergic medication. Across sessions, we varied stimulation (on, off) and dopaminergic medication (on, off). Reaction time (RT) results of the PD patients and their age-matched controls showed a consistent pattern of RT costs and benefits generated by anti-cues with short and long preparation intervals, respectively. This pattern was evident in all sessions, except when DBS stimulation and medication were off. In this condition PD patients showed no RT benefits. These findings are discussed in terms of an executive control process that suppresses the automatic but inappropriate response activation generated by anti-cues. In PD this mechanism is severely compromised but it can be remediated by dopaminergic medication and DBS, suggesting an essential role of the basal ganglia in the selection and suppression of competing responses. 相似文献
986.
Amin I Ilyas M Qazi J Bashir R Yadav JS Mansoor S Fauquet CM Briddon RW 《Virus genes》2011,42(2):272-281
Five genes encoded by Banana bunchy top virus (BBTV) originating from Pakistan were expressed in Nicotiana benthamiana using a Potato virus X (PVX) vector. Expression of the master replication-associated protein (mRep) and movement protein
(MP) resulted in necrotic cell death of inoculated tissues, as well as leaf curling and necrosis along the veins in newly
emerging leaves. The systemic necrosis induced by the expression of MP was discolored (dark) in comparison to that induced
by mRep. Expression of the cell-cycle link protein (Clink), the coat protein (CP), and the nuclear shuttle protein from the
PVX vector induced somewhat milder symptoms, consisting of mild leaf curling and mosaic, although expression of the CP caused
a necrotic response in inoculated leaf. The accumulation of viral RNA was enhanced by MP, Clink, and CP. Of the five BBTV-encoded
gene products two, the MP and Clink, stabilized GFP-specific mRNA and reduced GFP-specific small interfering RNA in N. benthamiana line 16c when expressed under the control of the 35S promoter and co-inoculated with a construct for the expression of GFP
hairpin RNA construct. These results identified MP and Clink as suppressors of RNA silencing. Taken together the ability of
MP to induce severe symptoms in plants and suppress RNA silencing implicates this product as a major pathogenicity determinant
of BBTV. 相似文献
987.
Hassanpour G Mohebali M Raeisi A Abolghasemi H Zeraati H Alipour M Azizi E Keshavarz H 《Parasitology research》2011,108(6):1519-1523
The transmission of malaria by blood transfusion was one of the first transfusion-transmitted infections recorded in the world.
Transfusion-transmitted malaria may lead to serious problems because infection with Plasmodium falciparum may cause rapidly fatal death. This study aimed to compare real-time polymerase chain reaction (real-time PCR) with rapid
diagnostic test (RDT) and light microscopy for the detection of Plasmodium spp. in blood transfusion, both in endemic and non-endemic areas of malaria disease in Iran. Two sets of 50 blood samples
were randomly collected. One set was taken from blood samples donated in blood bank of Bandar Abbas, a city located in a malarious-endemic
area, and the other set from Tehran, a non-endemic one. Light microscopic examination on both thin and thick smears, RDTs,
and real-time PCR were performed on the blood samples and the results were compared. Thin and thick light microscopic examinations
of all samples as well as RDT results were negative for Plasmodium spp. Two blood samples from endemic area were positive only with real-time PCR. It seems that real-time PCR as a highly sensitive
method can be helpful for the confirmation of malaria infection in different units of blood transfusion organization especially
in malaria-endemic areas where the majority of donors may be potentially infected with malaria parasites. 相似文献
988.
This study was conducted to identify genetic characteristics of Besnoitia spp. isolated from goat in Iran. Molecular analysis of two portions of nuclear ribosomal DNA (ITS1 and ITS2) was used for
the genetic characterization of the Besnoitia species. Comparison of the sequencing data of the Iranian Besnoitia samples obtained in the present study (GenBank accession number HM008988) with those previously reported for other Besnoitia spp. in the GenBank database revealed a particularly close relationship between the present goat Besnoitia samples and the Besnoitia samples from the cattle, caribou, and equids (Besnoitia besnoiti, Besnoitia tarandi, and Besnoitia bennetti). This is the first use of a genetic approach to interrogate the identity of the species of Besnoitia infecting Iranian goats. Also, the results of the present study showed the occurrence of a similar sequence polymorphism
for ITS1 and ITS2 in all Iranian isolates, which exhibit 100% identity in these ribosomal sequences, to those of B. besnoiti previously reported from Israel. Although the ITS1 sequence of Iranian goat isolates is identical to European cow isolates,
the ITS2 sequences derived from present Besnoitia genotype differed in one nucleotide position compared with other European B. besnoiti. Further studies should be employed based on this molecular data to identify the natural definitive host in order to complete
the life cycle of this distinct genotype of parasite. 相似文献
989.
Rohbanfard H Proteau L 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2011,214(4):567-576
Observation promotes motor skill learning. However, little is known about the type of model and conditions of observation
that can optimize learning. In this study, we investigated the effects of the model’s handedness and the observer’s viewpoint
on the learning of a complex spatiotemporal task. Four groups of right-handed participants observed, from either a first-
or third-person viewpoint, right- or left-handed models performing the task. Observation resulted in significant learning.
More importantly, observation of same-handed models resulted in improved learning as compared with observation of opposite-handed
models, regardless of the observer’s viewpoint. This suggests that the action observation network (AON) is more sensitive
to the model’s handedness than to the observer’s viewpoint. Our results are consistent with recent studies that suggest that
the AON is linked to or involves sensorimotor regions of the brain that simulate motor programming as if the observed movement
was performed with one’s own dominant hand. 相似文献
990.
Trempe M Sabourin M Rohbanfard H Proteau L 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2011,209(2):181-192
Motor learning is a process that extends beyond training sessions. Specifically, physical practice triggers a series of physiological
changes in the CNS that are regrouped under the term “consolidation” (Stickgold and Walker 2007). These changes can result in between-session improvement or performance stabilization (Walker 2005). In a series of three experiments, we tested whether consolidation also occurs following observation. In Experiment 1, participants
observed an expert model perform a sequence of arm movements. Although we found evidence of observation learning, no significant
difference was revealed between participants asked to reproduce the observed sequence either 5 min or 24 h later (no between-session
improvement). In Experiment 2, two groups of participants observed an expert model perform two distinct movement sequences
(A and B) either 10 min or 8 h apart; participants then physically performed both sequences after a 24-h break. Participants
in the 8-h group performed Sequence B less accurately compared to participants in the 5-min group, suggesting that the memory
representation of the first sequence had been stabilized and that it interfered with the learning of the second sequence.
Finally, in Experiment 3, the initial observation phase was replaced by a physical practice phase. In contrast with the results
of Experiment 2, participants in the 8-h group performed Sequence B significantly more accurately compared to participants
in the 5-min group. Together, our results suggest that the memory representation of a skill learned through observation undergoes
consolidation. However, consolidation of an observed motor skill leads to distinct behavioural outcomes in comparison with
physical practice. 相似文献