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排序方式: 共有2602条查询结果,搜索用时 140 毫秒
41.
Emanuele Angelucci Valeria Santini Anna Angela Di Tucci Giulia Quaresmini Carlo Finelli Antonio Volpe Giovanni Quarta Flavia Rivellini Grazia Sanpaolo Daniela Cilloni Flavia Salvi Giovanni Caocci Alfredo Molteni Daniele Vallisa Maria Teresa Voso Susanna Fenu Lorenza Borin Giancarlo Latte Giuliana Alimena Sergio Storti Alfonso Piciocchi Paola Fazi Marco Vignetti Sante Tura 《European journal of haematology》2014,92(6):527-536
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Rafael Bandeira Fabres Samir Khal de Souza Ana Lucia Cecconello Amanda Stapenhorst Azambuja Eduardo Farias Sanches Maria Flavia Marques Ribeiro Luciano Stürmer de Fraga 《Metabolic brain disease》2018,33(3):813-821
Progesterone displays a strong potential for the treatment of neonatal hypoxic-ischemic encephalopathy since it has been shown to be beneficial in the treatment of the central nervous system injuries in adult animals. Here, we evaluated the effects of the administration of progesterone (10 mg/kg) in seven-days-old male Wistar rats submitted to neonatal hypoxia-ischemia (HI). Progesterone was administered immediately before ischemia and/or 6 and 24 h after the onset of hypoxia. The body weight of the animals, the volume of brain lesion and the expression of p-Akt and procaspase-3 in the hippocampus were evaluated. All animals submitted to HI showed a reduction in the body weight. However, this reduction was more remarkable in those animals which received progesterone before surgery. Administration of progesterone was unable to reduce the volume of brain damage caused by HI. Moreover, no significant differences were observed in the expression of p-Akt and procaspase-3 in animals submitted to HI and treated with either progesterone or vehicle. In summary, progesterone did not show a neuroprotective effect on the volume of brain lesion in neonatal rats submitted to hypoxia-ischemia. Furthermore, progesterone was unable to modulate p-Akt and procaspase-3 signaling pathways, which may explain the absence of neuroprotection. On the other hand, it seems that administration of progesterone before ischemia exerts some systemic effect, leading to a remarkable reduction in the body weight. 相似文献
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Chen Zhao Anna-Claire Devlin Amit K. Chouhan Bhuvaneish T. Selvaraj Maria Stavrou Karen Burr Veronica Brivio Xin He Arpan R. Mehta David Story Christopher E. Shaw Owen Dando Giles E. Hardingham Gareth B. Miles Siddharthan Chandran 《Glia》2020,68(5):1046-1064
Mutations in C9orf72 are the most common genetic cause of amyotrophic lateral sclerosis (ALS). Accumulating evidence implicates astrocytes as important non-cell autonomous contributors to ALS pathogenesis, although the potential deleterious effects of astrocytes on the function of motor neurons remains to be determined in a completely humanized model of C9orf72-mediated ALS. Here, we use a human iPSC-based model to study the cell autonomous and non-autonomous consequences of mutant C9orf72 expression by astrocytes. We show that mutant astrocytes both recapitulate key aspects of C9orf72-related ALS pathology and, upon co-culture, cause motor neurons to undergo a progressive loss of action potential output due to decreases in the magnitude of voltage-activated Na+ and K+ currents. Importantly, CRISPR/Cas-9 mediated excision of the C9orf72 repeat expansion reverses these phenotypes, confirming that the C9orf72 mutation is responsible for both cell-autonomous astrocyte pathology and non-cell autonomous motor neuron pathophysiology. 相似文献
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Metalloproteinase Inhibition Protects against Reductions in Circulating Adrenomedullin during Lead‐induced Acute Hypertension 下载免费PDF全文
Regina A. Nascimento Gabryella Mendes Jose S. Possomato‐Vieira Victor Hugo Gonçalves‐Rizzi Hélio Kushima Flavia K. Delella Carlos A. Dias‐Junior 《Basic & clinical pharmacology & toxicology》2015,116(6):508-515
Intoxication with lead (Pb) results in increased blood pressure by mechanisms involving matrix metalloproteinases (MMPs). Recent findings have revealed that MMP type two (MMP‐2) seems to cleave vasoactive peptides. This study examined whether MMP‐2 and MMP‐9 levels/activities increase after acute intoxication with low lead concentrations and whether these changes were associated with increases in blood pressure and circulating endothelin‐1 or with reductions in circulating adrenomedullin and calcitonin gene‐related peptide (CGRP). Here, we expand previous findings and examine whether doxycycline (a MMPs inhibitor) affects these alterations. Wistar rats received intraperitoneally (i.p.) 1st dose 8 μg/100 g of lead (or sodium) acetate, a subsequent dose of 0.1 μg/100 g to cover daily loss and treatment with doxycycline (30 mg/kg/day) or water by gavage for 7 days. Similar whole‐blood lead levels (9 μg/dL) were found in lead‐exposed rats treated with either doxycycline or water. Lead‐induced increases in systolic blood pressure (from 143 ± 2 to 167 ± 3 mmHg) and gelatin zymography of plasma samples showed that lead increased MMP‐9 (but not MMP‐2) levels. Both lead‐induced increased MMP‐9 activity and hypertension were blunted by doxycycline. Doxycycline also prevented lead‐induced reductions in circulating adrenomedullin. No significant changes in plasma levels of endothelin‐1 or CGRP were found. Lead‐induced decreases in nitric oxide markers and antioxidant status were not prevented by doxycycline. In conclusion, acute lead exposure increases blood pressure and MMP‐9 activity, which were blunted by doxycycline. These findings suggest that MMP‐9 may contribute with lead‐induced hypertension by cleaving the vasodilatory peptide adrenomedullin, thereby inhibiting adrenomedullin‐dependent lowering of blood pressure. 相似文献
48.
Sandra M. Blois Flavia Piccioni Nancy Freitag Irene Tirado-González Petra Moschansky Rodrigo Lloyd Karin Hensel-Wiegel Matthias Rose Mariana G. Garcia Laura D. Alaniz Guillermo Mazzolini 《Angiogenesis》2014,17(1):119-128
During liver fibrogenesis the immune response and angiogenesis process are fine-tuned resulting in activation of hepatic stellate cells that produce an excess of extracellular matrix proteins. Dendritic cells (DC) play a central role modulating the liver immunity and have recently been implicated to favour fibrosis regression; although their ability to influence the development of fibrogenesis is unknown. Therefore, we explored whether the depletion of DC during early stages of liver injury has an impact in the development of fibrogenesis. Using the CD11c.DTR transgenic mice, DC were depleted in two experimental models of fibrosis in vivo. The effect of anti-angiogenic therapy was tested during early stages of liver fibrogenesis. DC depletion accelerates the development of fibrosis and as a consequence, the angiogenesis process is boosted. We observed up-regulation of pro-angiogenic factors together with an enhanced vascular endothelial growth factor (VEGF) bioavailability, mainly evidenced by the decrease of anti-angiogenic VEGF receptor 1 (also known as sFlt-1) levels. Interestingly, fibrogenesis process enhanced the expression of Flt-1 on hepatic DC and administration of sFlt-1 was sufficient to abrogate the acceleration of fibrogenesis upon DC depletion. Thus, DC emerge as novel players during the development of liver fibrosis regulating the angiogenesis process and thereby influencing fibrogenesis. 相似文献
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Mario Altamura Flavia A. Padalino Nicola Mammarella Beth Fairfield Angela Balzotti Alberto Di Domenico Elisa Frisullo Antonello Bellomo 《Psychiatry research》2013
In this study we investigated central and peripheral feature binding in a group of 24 high pre-morbid IQ patients with schizophrenia and 24 healthy controls. In particular, participants were asked to remember specific single (e.g., word, colour) or multiple features (e.g., coloured words) of experimental items with central (coloured word) vs. peripheral (a coloured frame) attributes in a working memory binding task. Performance of the patients was significantly inferior to that of controls, especially when required to remember the peripheral combination of multiple features. Results suggest that patients with schizophrenia may have difficulties in unitizing peripheral features in working memory. 相似文献
50.
Androgen and oestrogen receptors as potential prognostic markers for patients with ductal carcinoma in situ treated with surgery and radiotherapy 下载免费PDF全文
Sara Ravaioli Maria Maddalena Tumedei Flavia Foca Roberta Maltoni Andrea Rocca Ilaria Massa Elisabetta Pietri Sara Bravaccini 《International journal of experimental pathology》2017,98(5):289-295
Ductal carcinoma in situ (DCIS) is a heterogeneous disease that has been investigated less extensively than invasive breast cancer. Women with DCIS are mainly treated with conservative surgery almost exclusively followed by radiotherapy. However, as radiation treatment is not always effective, the search for biomarkers capable of identifying DCIS lesions that could progress to invasive cancer is ongoing. Although conventional biomarkers have been thoroughly studied in invasive tumours, little is known about the role played by androgen receptor (AR), widely expressed in DCIS. A series of 42 DCIS patients treated with quadrantectomy and radiotherapy were followed for a period of up to 95 months. Of these, 11 had recurrent DCIS or progressed to invasive cancer. All tumours were analysed for clinical pathological features. Conventional biomarkers and androgen receptor expression were determined by immunohistochemistry. Our results showed that AR was higher in tumours of relapsed patients than non‐relapsed patients (P value: 0.0005). Conversely, oestrogen receptor (ER) was higher, albeit not significantly, in non‐relapsed patients than in relapsed patients. AR/ER ratio was considerably different in the two subgroups (P value: 0.0033). Area under the curve (AUC) values were 0.85 for AR and 0.80 for the AR/ER ratio. These preliminary results highlight the potentially important role of both AR and the AR/ER ratio as prognostic markers in DCIS. 相似文献