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101.
de Brito Magalhães CL Drumond BP Novaes RF Quinan BR de Magalhães JC dos Santos JR Pinto Cdo A Assis MT Bonjardim CA Kroon EG Ferreira PC 《Archives of virology》2011,156(7):1173-1184
Apeu virus (APEUV) (family Bunyaviridae, genus Orthobunyavirus) was plaque purified and characterised by serological and molecular analysis. Neutralising assays confirmed cross-reactivity between purified APEUV clones and the Caraparu virus complex of group C orthobunyaviruses. Partial sequencing of the L, M and S segments of one APEUV clone (APEUV-CL5) was carried out. A phylogenetic tree constructed with the L amino acid sequences clustered APEUV-CL5 within the genus Orthobunyavirus, confirming its serological classification. Analysis of M segment sequences clustered APEUV-CL5 in the Caraparu virus complex (Group C), in agreement with serological tests and previous molecular characterisation. However, the sequence of the nucleocapsid gene (N) gave low identity values when compared to those of the group C viruses. The phylogenetic tree based on N nucleotide sequences clustered APEUV-CL5 next to the California and Bwamba groups. This remarkable S nucleotide variability suggests that APEUV-CL5 could be a genetic reassortant and that this evolutionary mechanism is present in the history of the group C viruses. 相似文献
102.
103.
Giuseppe M. V. Barbagallo Roberto Assietti Leonardo Corbino Giuseppe Olindo Pietro V. Foti Vittorio Russo Vincenzo Albanese 《European spine journal》2009,18(Z1):29-39
We report the clinical and radiological results on the safety and efficacy of an unusual surgical strategy coupling anterior
cervical discectomy and fusion and total disc replacement in a single-stage procedure, in patients with symptomatic, multilevel
cervical degenerative disc disease (DDD). The proposed hybrid, single-stage, fusion–nonfusion technique aims either at restoring or maintaining motion where appropriate or favouring bony fusion when indicated by degenerative
changes. Twenty-four patients (mean age 46.7 years) with symptomatic, multilevel DDD, either soft disc hernia or different
stage spondylosis per single level, with predominant anterior myeloradicular compression and absence of severe alterations
of cervical spine sagittal alignment, have been operated using such hybrid technique. Fifteen patients underwent a two-level
surgery, seven patients received a three-level surgery and two a four-level procedure, for a total of 59 implanted devices
(27 disc prostheses and 32 cages). Follow-up ranged between 12 and 40 months (mean 23.8 months). In all but one patient clinical
follow-up (neurological examination, Nurick scale, NDI, SF-36) demonstrated significant improvement; radiological evaluation
showed functioning disc prostheses (total range of motion 3–15°) and fusion through cages. None of the patients needed revision
surgery for persisting or recurring symptoms, procedure-related complications or devices dislocations. To the authors’ best
knowledge, this is the first study with the longest available follow-up describing a different concept in the management of
cervical multilevel DDD. Although larger series with longer follow-up are needed, in selected cases of symptomatic multilevel
DDD, the proposed surgical strategy appears to be a safe and reliable application of combined arthroplasty and arthrodesis
during a single surgical procedure. 相似文献
104.
P.T.G. Vianna Y.M.M. Castiglia J.R.C. Braz R.M. Viero S. Beier P.T.G. Vianna Filho A. Vitória G. Reinoldes Bizarria Guilherme M. de Assis Golim E. Deffune 《Transplantation proceedings》2009,41(10):4080-4082
Background
The purpose of this investigation was to examine the effect of isoflurane, remifentanil, and preconditioning in renal ischemia/reperfusion injury (IRI).Methods
All 52 male Wistar rats were anesthetized with isoflurane, intubated and mechanically ventilated. The animals were randomly divided into: S group (sham; n = 11) that underwent only right nephrectomy; as well as the I group of right nephrectomy and ischemia for 45 minutes by clamping of left renal artery. (n = 11); the IP (n = 9), the R (n = 10), and the RP (n = 11) groups. In addition, the R and RP animals received remifentanil (2 μg · kg−1 · min−1) during the entire experiment. The IP and RP group underwent ischemic preconditioning (IPC = three cycles of 5 minutes). Serum creatinine values were determined before and after IRI, as well as 24 hours later. In addition to an Histological study, cells from the left kidney were evaluated for apoptosis by flow cytometry (FCM).Results
The Creatinine value of 0.8 ± 0.2 mg/dl in the S group was significantly lower at 24 hours than the I 3.9 ± 1.5 mg/dl; IP 2.6 ± 1.7 mg/dl; R 3.3 ± 2.8 mg/dl; or RP 1.8 ± 0.5 mg/dl groups. The RP group value was significantly lower than those of the I, IP, and R groups (p < 0.05). The S group showed less proximal tubular cell damage than the I, IP, R, and RP groups (p < 0.05). The percentages of apoptotic cells (FITC+/PI−) were: S group = 11.6 ± 6.5; I = 16.7 ± 7.3; IP = 37.0 ± 28.4; R = 11.7 ± 6.6, and RP = 8.8 ± 1.5. The difference between the IP vs RP group was significant. Similar percentages of necrotic cells (FITC+/PI+) and intact cells (FITC−/PI−) were observed among the groups.Conclusions
Ischemic preconditioning showed no protective effect in the isoflurane group (IP) but when isoflurane was administered associated with remifentanil (RP), there was a beneficial effect on the kidney, as demonstrated by flow cytometry and serum creatinine values. 相似文献105.
P. Cabre A. Gonzalez-Quevedo A. Lannuzel M. Bonnan H. Merle S. Olindo N. Chausson R. Lara-Rodriguez D. Smadja J. Cabrera-Gomez 《Revue neurologique》2009,165(8-9):676-683
IntroductionData on epidemiology of neuromyelitis optica (NMO) remained scarce in the last century, but the recent development of diagnostic criteria now enables inclusion of both monophasic and relapsing NMO in epidemiologic studies. Given the rarity of NMO, multicentric studies are needed to confirm a presumed higher frequency in women and in populations of black/Asian ancestry. The Caribbean basin is a suitable area for collecting a large NMO cohort and to assess the prevalence, incidence, and mortality of this disorder.Patients and methodsThis population-based survey of the NMO spectrum in the French West Indies (FWI) and Cuba included 151 cases.ResultsNinety-eight patients (female/male ratio: 9.8) had NMO. Age of onset in NMO patients was 30.9 years. Mean annual incidence of NMO in the French West Indies for the period July 2002 to June 2007 was 0.20/100,000 inhabitants (IC 95% 0.05–0.35). Incidence rates were steady in the FWI during the 1992 to 2007 period. Decreasing mortality in the FWI during the 1992 to 2007 period explained the increasing prevalence which was 4.20/100,000 inhabitants (IC 95% 3.7–5.7) in June 2007. The prevalence of NMO in Cuba on November 30 2004 was 0.52/100,000 inhabitants. (IC 95% 0.39–0.67). Prevalence rates did not differ significantly by ethnic group in Cuba, however, black Cubans exhibited the highest prevalence.DiscussionEpidemiologic studies on NMO in each population are needed to determine whether aggressive therapies can reduce the mortality of this devastating disorder.ConclusionIn the Caribbean basin, NMO involves almost exclusively young women; the epidemiologic data confirm its predilection for populations of African ancestry. In the FWI, recent and aggressive therapy has lowered mortality but with an increase in the prevalence of NMO. 相似文献
106.
Danieli Valnes Magni Ana Flávia Furian Mauro Schneider Oliveira Mauren Assis Souza Fabiane Lunardi Juliano Ferreira Carlos Fernando Mello Luiz Fernando Freire Royes Michele Rechia Fighera 《International journal of developmental neuroscience》2009
Glutaric acidemia type I (GA-I) is an inherited metabolic disease characterized by accumulation of glutaric acid (GA) and striatal degeneration. Although growing evidence suggests that excitotoxicity and oxidative stress play central role in the neuropathogenesis of this disease, mechanism underlying striatal damage in this disorder is not well established. Thus, we decided to investigate the in vitro effects of GA 10 nM (a low concentration that can be present initial development this disorder) on l-[3H]glutamate uptake and reactive oxygen species (ROS) generation in synaptosomes from striatum of rats. GA reduced l-[3H]glutamate uptake in synaptosomes from 1 up to 30 min after its addition. Furthermore, we also provided some evidence that GA competes with the glutamate transporter inhibitor l-trans-pyrrolidine-2,4-dicarboxylate (PDC), suggesting a possible interaction of GA with glutamate transporters on synaptosomes. Moreover, GA produced a significant decrease in the VMAX of l-[3H]glutamate uptake, but did not affect the KD value. Although the GA did not show oxidant activity per se, it increased the ROS generation in striatal synaptosomes. To evaluate the involvement of reactive species generation in the GA-induced l-[3H]glutamate uptake inhibition, trolox (0.3, 0.6 and 6 μM) was added on the incubation medium. Statistical analysis showed that trolox did not decrease inhibition of GA-induced l-[3H]glutamate uptake, but decreased GA-induced reactive species formation in striatal synaptosomes (1, 3, 5, 10, 15 and 30 min), suggesting that ROS generation appears to occur secondarily to glutamatergic overstimulation in this model of organic acidemia. Since GA induced DCFH oxidation increase, we evaluate the involvement of glutamate receptor antagonists in oxidative stress, showing that CNQX, but not MK-801, decreased the DCFH oxidation increase in striatal synaptosomes. Furthermore, the results presented in this report suggest that excitotoxicity elicited by low concentration of GA, could be in part by maintaining this excitatory neurotransmitter in the synaptic cleft by non-competitive inhibition of glutamate uptake. Thus the present data may explain, at least partly, initial striatal damage at birth, as evidenced by acute bilateral destruction of caudate and putamen observed in children with GA-I. 相似文献
107.
María Amparo Assis Cristian Hansen Victoria Lux-Lantos Liliana Marina Cancela 《Brain, behavior, and immunity》2009,23(4):464-473
Administration of psychostimulants can elicit a sensitized response to the stimulating and reinforcing properties of the drugs, although there is scarce information regarding their effects at immune level. We previously demonstrated that an acute exposure to amphetamine (5 mg/kg, i.p.) induced an inhibitory effect on the splenic T-cell proliferative response, along with an increase in met-enkephalin at limbic and immune levels, 4 days following drug administration. In this study, we evaluated the amphetamine-induced effects at weeks one and three after the same single dose treatment (5 mg/kg, i.p.) on the lymphoproliferative response and on the met-enkephalin in the nucleus accumbens (NAc), prefrontal cortex (PfC), spleen and thymus. It was demonstrated that these effects disappeared completely after three weeks, although re-exposure to an amphetamine challenge induced the expression of sensitization to the effects of amphetamine on the lymphoproliferative response and on the met-enkephalin from NAc, spleen and thymus, but not in the PfC. Pre-treatment with MK-801 (0.1 mg/kg, i.p.), an N-methyl-d-aspartate (NMDA) glutamatergic receptor antagonist, blocked the effects of a single amphetamine exposure on the lymphoproliferative response and on met-enkephalin in the NAc and spleen. Furthermore, the NMDA receptor antagonist administered prior to amphetamine challenge also blocked the expression of sensitization in both parameters evaluated. These findings show a long-lasting amphetamine-induced sensitization phenomenon at the immune level in a parallel way to that occurring in the limbic and immune enkephalineric system. A glutamate mechanism is implied in the long-term amphetamine-induced effects at immune level and in the met-enkephalin from NAc and spleen. 相似文献
108.
Vieira LM Dusse LM Fernandes AP Martins-Filho OA de Bastos M Ferreira MF Cooper AJ Lwaleed BA Carvalho MG 《Thrombosis research》2007,119(2):157-165
INTRODUCTION: Tissue factor (TF) is the main physiological initiator of blood coagulation; it is membrane-bound on monocytes (mTF) and free in plasma (pTF). Abnormal expression of TF by monocytes has been implicated in various diseases. We therefore quantified monocytes expressing TF and pTF levels in patients with lower-limb deep venous thrombosis (DVT). MATERIALS AND METHODS: DVT was confirmed by Duplex Scan. Blood mTF levels under resting condition (baseline), after incubation without (unstimulated) and with (stimulated) lipopolysaccharide (LPS), and total mTF levels were determined by flow cytometry using two analytical methods (Histogram and Quadrant-Statistics). Plasma TF levels were measured using an enzyme-linked immunoabsorbent assay (ELISA). Results were compared with age-matched controls. RESULTS: Histogram analysis in patients with DVT showed significantly elevated mTF levels for baseline, unstimulated and total mTF over controls. For Quadrant-Statistics, DVT patients also showed significantly raised baseline, unstimulated, stimulated and total mTF. Similarly, pTF levels were significantly raised in subjects with DVT compared to controls. Baseline mTF levels correlated with pTF levels by Histogram and Quadrant-Statistics analysis. Using the relative operating characteristic (ROC) curve, baseline mTF and pTF assays displayed sensitivity and specificity in detecting DVT. Quadrant-Statistics baseline mTF and pTF gave the best discrimination. CONCLUSIONS: The TF assays used in this study showed acceptable sensitivity and specificity and are cost-effective and practical. Therefore, they should be considered in patients with, or at risk of, DVT. 相似文献
109.
110.
Guerra LL Teixeira-Carvalho A Giunchetti RC Martins-Filho OA Reis AB Corrêa-Oliveira R 《Parasitology research》2009,104(3):611-622
During Leishmania infection, tissue parasitism at different sites may differ and imply distinct immunopathological patterns during canine visceral
leishmaniasis (CVL). For this reason, we have assessed by flow cytometry the impact of spleen and skin parasite density on
the phenotypic profile of splenocytes and circulating leukocytes of 40 Brazilian dogs naturally infected by Leishmania chagasi categorized according to splenic and cutaneous parasite load. Our major statistically significant findings demonstrated that
dogs with splenic high parasitism presented a significant decrease in absolute counts of CD5+ T lymphocytes in comparison with dogs presenting splenic medium parasitism. Moreover, a decrease in the absolute number of
circulating monocytes was observed as a hallmark of high parasitism. The increased frequency of CD8+ T cells is associated with low splenic parasitism during CVL. Although we did not found any significant differences between
the immunophenotypic analysis performed in circulating lymphocytes according to cutaneous parasite load, there were negative
correlations between CD5+ and CD8+ T cells and cutaneous parasite density reemphasizes the role of T cell-mediated immune response in resistance mechanisms
during ongoing CVL. These results add new insights about the pathogenesis of CVL and may help in the establishment of additional
tools for future studies on drugs and vaccine approaches. 相似文献