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排序方式: 共有952条查询结果,搜索用时 15 毫秒
81.
Agenesis of the gallbladder is a rare anomaly that is usually asymptomatic, but sometimes the patients may have symptoms compatible with a biliary disorder like cholelithiasis. Its preoperative diagnosis is often difficult, especially if dysplastic cyst is associated and simulates the gallbladder. When the diagnosis is doubtful its confirmation and treatment of dysplastic cyst require open surgery, careful dissection of the common bile duct to avoid biliary lesions and intraoperative ultrasonography or cholangiography to be performed to exclude other associated anomalies. The Authors describe the case of agenesis of gallbladder and dysplastic cyst associated and comment on its clinical, diagnostic, and therapeutic aspects. 相似文献
82.
Onorati F Forte A Mastroroberto P Santè P Esposito S Pezzo F Agozzino L Cipollaro M Cascino A Renzulli A 《The Journal of surgical research》2007,143(2):300-310
BACKGROUND: Hypertension has been traditionally considered a risk factor for restenosis following carotid arteriotomy. Genetic and morphological response to carotid arteriotomy in normotensive Wystar-Kyoto (WKY), spontaneously hypertensive (SHR), and Milan hypertensive (MHS) rats were analyzed. MATERIAL AND METHODS: C-myc, angiotensin II receptor-1 (AT1), angiotensin II receptor-2 (AT2), endothelin-1 receptor A (ET(A)), endothelin-1 receptor B (ET(B)), Bcl-2 family-members (Bcl-2/Bax, Bcl-X(L/S)) were analyzed in surgically injured as well as uninjured carotids of WKY and hypertensive strains (HS). Thirty-day histology and morphometry were accomplished on injured and uninjured carotids. RESULTS: C-myc mRNA is activated earlier and/or to a greater extent in hypertensive strains than in WKY. AT1 mRNA increases in WKY after injury, while it decreases in SHR and MHS. AT2 shows the opposite, decreasing in WKY and increasing in hypertensive strains. ET(A) mRNA decreases in all strains although with different timing and levels, associated with a replacement by ET(B) mRNA. Bcl-2/Bax ratio gradually decreases in WKY, while it shows only a transient decrease in SHR and MHS 4 h after the injury. Negative remodeling is observed in all injured carotids, although neointima was detected in WKY only. Thirty days following arteriotomy, morphometry demonstrated a significant decrease of luminal area, with consistent gain in the medial area in WKY, whereas hypertensive strains showed significant increase of the luminal area, consistent with a contemporary decrease of the medial area. CONCLUSIONS: Vaso-relaxant AT2 and ET(B) induced limited vasoconstriction in HS. Less apoptosis in hypertensive rats reduced cell proliferation, contrasting c-myc. These responses favorably modulated media/lumen area ratio following arteriotomy in HS. 相似文献
83.
Giovanni Di Bernardo Stefania Del Gaudio Umberto Galderisi Antonino Cascino Marilena Cipollaro 《Annals of human genetics》2009,73(4):429-437
Archaeological, anthropological and pathological data suggest that thirteen skeletons found in a house at the Pompeii archaeological site, dated to 79 A.D., belong to one family. To verify this and to identify the relationships between these individuals, we analyzed DNA extracted from bone specimens. Specifically, hypervariable segment 1 (HVS1) of the human mitochondrial DNA (mtDNA) control region was amplified in two overlapping polymerase chain reactions and the sequences were compared to the revised Cambridge Reference Sequence. As independent controls, other polymorphic sites in HVS1, HVS2 and in the coding region were analyzed. We also amplified some short tandem repeats of the thirteen specimens. This study revealed that six of the thirteen individuals are indeed closely related. 相似文献
84.
Pia L Folegatti A Guagliardo M Genero R Gindri P 《Cortex; a journal devoted to the study of the nervous system and behavior》2009,45(3):293-299
Unilateral neglect patients typically omit to cancel contralesional targets. Moreover, they can repeatedly cancel ipsilesional stimuli exhibiting what is termed ‘perseverative behavior’. Two alternative accounts of this behavior have been proposed. According to one of them, it is considered as integral to neglect and due either to a perceptual (allochiria), or a premotor (directional hypokinesia) pathological mechanism leading to the ipsilesional displacement of contralesional responses. According to the other one, perseverations are interpreted as the consequence of motor-control-disinhibition co-occurring with, although independent of, spatial neglect. We compared some crucial predictions of these two hypotheses on a group of 10 right-brain-damaged patients, eight with neglect and two without neglect, showing a perseverative behavior in both conventional and experimental cancellation tasks. In our experiment, the spatial location and the numerosity of targets were manipulated to obtain different degrees of horizontal alignment between targets on the left and on the right of the central vertical axis of the sheet. We found that ipsilesional perseverations were not influenced by left neglected targets and were not correlated to neglect severity. Additionally, perseverative errors were associated with right basal ganglia lesions rather than with presence of neglect. These findings support the view that two different pathological mechanisms might be involved in left spatial neglect and ipsilesional perseverative behavior. 相似文献
85.
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87.
Dicuonzo F Palma M Fiume M Scarpello R Lefons V Maghenzani M Carella A 《Journal of child neurology》2008,23(11):1260-1266
Fetal stroke can occur between the 14th week of pregnancy and the beginning of labor. The incidence is approximately 17-35 of 100,000 live births. Risk factors are correlated to the mother, the pregnancy, or the factors associated with the fetus itself. Computerized tomography and magnetic resonance imaging are the most commonly used imaging techniques. The authors studied 3 cases with neurological symptoms by magnetic resonance imaging and magnetic resonance-angiography. In these cases, the authors found massive involvement of the left hemisphere that was presumptively correlated with the persistence of the oval foramen. Magnetic resonance-angiography showed a flow reduction in the left cerebral vessels, and in 1 case, there was also persistence of the fetal primitive trigeminal artery. The discrepancy between the extent of the cerebral lesions and the neurological symptoms is associated with cerebral plasticity, which is greater in damage occurring early in fetal life. 相似文献
88.
Aiello S Cassis P Cassis L Tomasoni S Benigni A Pezzotta A Cavinato RA Cugini D Azzollini N Mister M Longaretti L Thomson AW Remuzzi G Noris M 《Transplantation》2007,83(4):474-484
BACKGROUND: We previously documented that rat bone marrow-derived dendritic cells (DCs), transfected with an adenovirus encoding a dominant negative form of IKK2 (dnIKK2), have impaired allostimulatory capacity and generate CD4 T cells with regulatory function. Here we investigate the potency, the phenotype, and the mechanism of action of dnIKK2-DC-induced regulatory cells and we evaluated their tolerogenic properties in vivo. METHODS: Brown Norway (BN) transfected dnIKK2-DCs were cultured with Lewis (LW) lymphocytes in primary mixed lymphocyte reaction (MLR). CD4 T cells were purified from primary MLR and incubated in secondary coculture MLR with LW lymphocytes. Phenotypic characterization was performed by fluorescence-activated cell sorting and real-time polymerase chain reaction. The tolerogenic potential of CD4 T cells pre-exposed to dnIKK2-DCs was evaluated in vivo in a model of kidney allotransplantation. RESULTS: CD4 T cells pre-exposed to dnIKK2-DCs were CD4CD25 and expressed interleukin (IL)-10, transforming growth factor-beta, interferon-gamma, IL-2, and inducible nitric oxide synthase (iNOS). These cells (dnIKK2-Treg), cocultured (at up to 1:10 ratio) with a primary MLR, suppressed T-cell proliferation to alloantigens. The regulatory effect was cell-to-cell contact-independent since it was also observed in a transwell system. A nitric oxide synthase inhibitor significantly reverted dnIKK2-Treg-mediated suppression, whereas neutralizing antibodies to IL-10 and TGF-beta had no significant effect. DnIKK2-Treg given in vivo to LW rats prolonged the survival of a kidney allograft from BN rats (the donor rat strain used for generating DCs). CONCLUSIONS: DnIKK2-Treg is a unique population of CD4CD25 T cells expressing high levels of iNOS. These cells potently inhibit T-cell response in vitro and induce prolongation of kidney allograft survival in vivo. 相似文献
89.
90.
Liontos M Koutsami M Sideridou M Evangelou K Kletsas D Levy B Kotsinas A Nahum O Zoumpourlis V Kouloukoussa M Lygerou Z Taraviras S Kittas C Bartkova J Papavassiliou AG Bartek J Halazonetis TD Gorgoulis VG 《Cancer research》2007,67(22):10899-10909
The accurate execution of DNA replication requires a strict control of the replication licensing factors hCdt1 and hCdc6. The role of these key replication molecules in carcinogenesis has not been clarified. To examine how early during cancer development deregulation of these factors occurs, we investigated their status in epithelial lesions covering progressive stages of hyperplasia, dysplasia, and full malignancy, mostly from the same patients. Abnormal accumulation of both proteins occurred early from the stage of dysplasia. A frequent cause of unregulated hCdc6 and hCdt1 expression was gene amplification, suggesting that these components can play a role per se in cancer development. Overexpression of hCdt1 and hCdc6 promoted rereplication and generated a DNA damage response, which activated the antitumor barriers of senescence and apoptosis. Generating an inducible hCdt1 cellular system, we observed that continuous stimulus by deregulated hCdt1 led to abrogation of the antitumor barriers and resulted in the selection of clones with more aggressive properties. In addition, stable expression of hCdc6 and hCdt1 in premalignant papilloma cells led to transformation of the cells that produced tumors upon injection into nude mice depicting the oncogenic potential of their deregulation. 相似文献