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排序方式: 共有371条查询结果,搜索用时 15 毫秒
1.
Laura Tapella Teresa Soda Lisa Mapelli Valeria Bortolotto Heather Bondi Federico A. Ruffinatti Giulia Dematteis Alessio Stevano Marianna Dionisi Simone Ummarino Annalisa Di Ruscio Carla Distasi Mariagrazia Grilli Armando A. Genazzani Egidio D'Angelo Francesco Moccia Dmitry Lim 《Glia》2020,68(3):543-560
Astrocytes perform important housekeeping functions in the nervous system including maintenance of adequate neuronal excitability, although the regulatory mechanisms are currently poorly understood. The astrocytic Ca2+/calmodulin-activated phosphatase calcineurin (CaN) is implicated in the development of reactive gliosis and neuroinflammation, but its roles, including the control of neuronal excitability, in healthy brain is unknown. We have generated a mouse line with conditional knockout (KO) of CaN B1 (CaNB1) in glial fibrillary acidic protein-expressing astrocytes (a stroglial c alcin eurin KO [ACN-KO]). Here, we report that postnatal and astrocyte-specific ablation of CaNB1 did not alter normal growth and development as well as adult neurogenesis. Yet, we found that specific deletion of astrocytic CaN selectively impairs intrinsic neuronal excitability in hippocampal CA1 pyramidal neurons and cerebellar granule cells (CGCs). This impairment was associated with a decrease in after hyperpolarization in CGC, while passive properties were unchanged, suggesting impairment of K+ homeostasis. Indeed, blockade of Na+/K+-ATPase (NKA) with ouabain phenocopied the electrophysiological alterations observed in ACN-KO CGCs. In addition, NKA activity was significantly lower in cerebellar and hippocampal lysates and in pure astrocytic cultures from ACN-KO mice. While no changes were found in protein levels, NKA activity was inhibited by the specific CaN inhibitor FK506 in both cerebellar lysates and primary astroglia from control mice, suggesting that CaN directly modulates NKA activity and in this manner controls neuronal excitability. In summary, our data provide formal evidence for the notion that astroglia is fundamental for controlling basic neuronal functions and place CaN center-stage as an astrocytic Ca2+-sensitive switch. 相似文献
2.
Vignali L Saia F Manari A Santarelli A Rubboli A Varani E Piovaccari G Menozzi A Percoco G Benassi A Rusticali G Marzaroli P Guastaroba P Grilli R Maresta A Marzocchi A 《The American journal of cardiology》2008,101(7):947-952
Percutaneous revascularization of saphenous vein grafts (SVGs) remains a challenging task. Drug-eluting stents (DESs) have been shown to decrease the incidence of restenosis in de novo native coronary artery lesions. However, their clinical value in SVGs remains to be established. We compared long-term clinical outcomes of percutaneous coronary intervention with DESs and bare metal stents (BMSs) for de novo lesions in SVGs. In a large prospective, multicenter registry, 360 patients underwent stenting of a de novo lesion in SVGs using BMSs (288 patients) or DESs (72 patients). Incidence of major adverse cardiac events (MACEs), including all-cause mortality, reinfarction, and target vessel revascularization, was recorded at a 12-month follow-up. Compared with the DES group, patients receiving BMSs were more likely to be men, to have chronic renal insufficiency or higher Charlson scores, but less likely to have undergone previous percutaneous coronary intervention. Incidence of MACEs at 12-month follow-up was similar in the 2 groups (17.8% in DES group vs 20.3% in BMS group, respectively, p = 0.460). Cox regression analysis identified age, chronic renal failure, cardiogenic shock at presentation, and ostial location of stenosis as independent predictors of long-term MACEs. In conclusion, our data suggest that rates of 12-month MACEs associated with the use of DESs and BMSs are similar in patients undergoing treatment of de novo lesions in SVGs. 相似文献
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Marzocchi A Piovaccari G Manari A Aurier E Benassi A Saia F Casella G Varani E Santarelli A Guastaroba P Grilli R Maresta A 《The American journal of cardiology》2005,95(12):1409-1414
We evaluated the clinical effect of selective use of sirolimus-eluting stents (SESs) in real-world, high-risk patients. A total of 4,237 consecutive patients who underwent percutaneous coronary intervention (SES, n = 872, bare metal stents [BMSs], n = 3,365) was enrolled in a prospective regional survey. A prespecified high-risk subset of patients was selected on the basis of clinical and angiographic characteristics. A propensity score analysis was performed to compare patients who received SESs with those who received BMSs. Patients in the SES group more often had diabetes and more frequently had previous myocardial infarction or coronary revascularization, type C lesions, and multivessel procedures. Patients who presented with acute myocardial infarction were treated more often with BMSs. At 9 months, the use of SESs was associated with fewer major adverse cardiac events (death, myocardial infarction, or target lesion revascularization; hazard ratio 0.56, 95% confidence interval 0.37 to 0.85) and target lesion revascularizations (hazard ratio 0.43, 95% confidence interval 0.20 to 0.91). This decrease was more evident in a prespecified high-risk subgroup of patients (major adverse cardiac events, 8.0% SES vs 15.6% BMS, hazard ratio 0.45, 95% confidence interval 0.29 to 0.72). We conclude that selective SES use in real-world patients who have high-risk clinical and angiographic characteristics is associated with significant decreases in major adverse cardiac events and repeat revascularizations compared with BMS use. 相似文献
6.
Assaf Graif Christopher J. Grilli George Kimbiris Demetrios J. Agriantonis Omar Z. Chohan Charles R. Fedele Mandip S. Gakhal Ansar Z. Vance Daniel A. Leung 《Journal of vascular and interventional radiology : JVIR》2017,28(10):1339-1347
Purpose
To compare the technical and clinical effectiveness of ultrasound-accelerated endovascular thrombolysis (USAT) versus pigtail catheter–directed thrombolysis (PCDT) for the treatment of acute pulmonary embolism (PE).Materials and Methods
A single-center retrospective study of patients treated with USAT or PCDT for acute massive or submassive PE between January 2010 and December 2016 was performed by reviewing electronic medical records. Sixty treatments were reviewed (mean patient age, 56.7 y ± 14.6), including 52 cases of submassive PE (21 treated with USAT, 31 with PCDT) and 8 cases of massive PE (3 treated with USAT, 5 with PCDT). Endpoints included pulmonary artery pressure (PAP), Miller PE severity index, tissue plasminogen activator (TPA) dose, infusion duration, procedural variables, and complications.Results
Demographics, PE severity, and right:left ventricular diameter ratios were similar between groups. USAT and PCDT significantly reduced mean PAP (reductions of 7.4 mm Hg [P = .002] and 8.2 mm Hg [P < .001], respectively) and Miller index scores (reductions of 45.8% [P < .001] and 53% [P < .001], respectively) with similar effectiveness (P = .47 and P = .15, respectively). Procedure (P < .001) and fluoroscopy (P = .001) times were significantly longer in the USAT group. The USAT group underwent fewer sessions (2.2 ± 0.6 vs 2.4 ± 0.6; P = .17) with shorter infusion times (23.9 h ± 8.8 vs 30.4 h ± 12.6; P = .065) and a lower total dose of TPA (27.1 mg ± 11.3 vs 30.4 mg ± 12.6; P = .075) compared with the PCDT group, but the differences were not significant. Complications (P = .07) and 30-day mortality rates (P = .56) were not significantly different between groups.Conclusions
USAT and PCDT demonstrated comparable effectiveness and safety in the treatment of patients with acute PE. 相似文献7.
TGF‐β2 and TGF‐β3 from cultured β‐amyloid‐treated or 3xTg‐AD‐derived astrocytes may mediate astrocyte–neuron communication 下载免费PDF全文
Laura Tapella Matteo Cerruti Isabella Biocotino Alessio Stevano Francesca Rocchio Pier Luigi Canonico Mariagrazia Grilli Armando A. Genazzani Dmitry Lim 《The European journal of neuroscience》2018,47(3):211-221
Astrocytes participate in the development and resolution of neuroinflammation in numerous ways, including the release of cytokines and growth factors. Among many, astrocytes release transforming growth factors beta (TGF‐β) TGF‐β1, TGF‐β2 and TGF‐β3. TGF‐β1 is the most studied isoform, while production and release of TGF‐β2 and TGF‐β3 by astrocytes have been poorly characterized. Here, we report that purified cultures of hippocampal astrocytes produce mainly TGF‐β3 followed by TGF‐β2 and TGF‐β1. Furthermore, astrocytes release principally the active form of TGF‐β3 over the other two. Changes in release of TGF‐β were sensitive to the calcineurin (CaN) inhibitor FK506. Starvation had no effect on TGF‐β1 and TGF‐β3 while TGF‐β2 mRNA was significantly up‐regulated in a CaN‐dependent manner. We further investigated production and release of astroglial TGF‐β in Alzheimer's disease‐related conditions. Oligomeric β‐amyloid (Aβ) down‐regulated TGF‐β1, while up‐regulating TGF‐β2 and TGF‐β3, in a CaN‐dependent manner. In cultured hippocampal astrocytes from 3xTg‐AD mice, TGF‐β2 and TGF‐β3, but not TGF‐β1, were up‐regulated, and this was CaN‐independent. In hippocampal tissues from symptomatic 3xTg‐AD mice, TGF‐β2 was up‐regulated with respect to control mice. Finally, treatment with recombinant TGF‐βs showed that TGF‐β2 and TGF‐β3 significantly reduced PSD95 protein in cultured hippocampal neurons, and this effect was paralleled by conditioned media from Aβ‐treated astrocytes or from astrocytes from 3xTg‐AD mice. Taken together, our data suggest that TGF‐β2 and TGF‐β3 are produced by astrocytes in a CaN‐dependent manner and should be investigated further in the context of astrocyte‐mediated neurodegeneration. 相似文献
8.
In ventral mesencephalic neurons cultured for five days the K+-evoked 3H-dopamine release is mediated through activation of N-type Ca2+ channels, while L- or T-type channels appear to be inactive. In contrast, veratridine-elicited release of 3H-dopamine that was attenuated by tetrodotoxin was not altered by N-, L-, nor T-type Ca2+ channel blockers. 相似文献
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10.
Following its reintroduction in 1978 influenza A H1N1 spread widely in the child population. By the autumn of 1979, 75% of 11-year olds entering a boys' boarding school had detectable antibody. The protective effect of previous experience could be assessed during two outbreaks in the school. In the first outbreak in 1979, 90% of those known to have been infected in the previous year were protected against reinfection. In 1983 after strains of the H1N1 subtype had undergone antigenic drift a large outbreak occurred. It was estimated that past infection conferred protection against clinical influenza in 55%. Where past infection resulted in the presence of antibody which reacted with the outbreak strain the attack rate was further reduced. A large number of sub-clinical infections was detected in all groups. 相似文献