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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
31.
Krishna S. Iyer 《Platelets》2020,31(4):474-482
Abstract Platelets are small, anucleated effector cells that play an important role in linking the hemostatic and inflammatory processes in the body. Platelet function is known to be altered under various inflammatory conditions including aging. A gain in platelet function during aging can increase the risk of thrombotic events, such as stroke and acute myocardial infarction. Anti-platelet therapy is designed to reduce risk of serious cerebrovascular and cardiovascular events, but the adverse consequences of therapy, such as risk for bleeding increases with aging as well. Age-associated comorbidities such as obesity, diabetes, and hyperlipidemia also contribute to increased platelet activity and thus can enhance the risk of thrombosis. Therefore, identification of unique mechanisms of platelet dysfunction in aging and in age-associated comorbidities is warranted to design novel antiplatelet drugs. This review outlines some of the current areas of research on aging-related mechanisms of platelet hyperactivity and addresses the clinical urgency for designing anti-platelet therapies toward novel molecular targets in the aging population. 相似文献
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Mohid S Khan Thomas Walter Amy Buchanan-Hughes Emma Worthington Lucie Keeber Marion Feuilly Enrique Grande 《World journal of gastroenterology : WJG》2020,26(30):4537-4556
BACKGROUND Approximately 20% of patients with neuroendocrine tumours(NETs) develop carcinoid syndrome(CS),characterised by flushing and diarrhoea.Somatostatin analogues or telotristat can be used to control symptoms of CS through inhibition of serotonin secretion.Although CS is often the cause of diarrhoea among patients with gastroenteropancreatic NETs(GEP-NETs),other causes to consider include pancreatic enzyme insufficiency(PEI),bile acid malabsorption and small intestinal bacterial overgrowth.If other causes of diarrhoea unrelated to serotonin secretion are mistaken for CS diarrhoea,these treatments may be ineffective against the diarrhoea,risking detrimental effects to patient quality of life.AIM To identify and synthesise qualitative and quantitative evidence relating to the differential diagnosis of diarrhoea in patients with GEP-NETs.METHODS Electronic databases(MEDLINE,Embase and the Cochrane Library) were searched from inception to September 12,2018 using terms for NETs and diarrhoea.Congresses,systematic literature review bibliographies and included articles were also hand-searched.Any study designs and publication types were eligible for inclusion if relevant data on a cause(s) of diarrhoea in patients with GEP-NETs were reported.Studies were screened by two independent reviewers at abstract and full-text stages.Framework synthesis was adapted to synthesise quantitative and qualitative data.The definition of qualitative data was expanded to include all textual data in any section of relevant publications.RESULTS Forty-seven publications(44 studies) were included,comprising a variety of publication types,including observational studies,reviews,guidelines,case reports,interventional studies,and opinion pieces.Most reported on PEI on/after treatment with somatostatin analogs;9.5%-84% of patients with GEP-NETs had experienced steatorrhoea or confirmed PEI.Where reported,14.3%–50.7% of patients received pancreatic enzyme replacement therapy.Other causes of diarrhoea reported in patients with GEP-NETs included bile acid malabsorption(80%),small intestinal bacterial overgrowth(23.6%-62%),colitis(20%) and infection(7.1%).Diagnostic approaches included faecal elastase,breath tests,tauroselcholic(selenium-75) acid(Se HCAT) scan and stool culture,although evidence on the effectiveness or diagnostic accuracy of these approaches was limited.Assessment of patient history or diarrhoea characteristics was also reported as initial approaches for investigation.From the identified evidence,if diarrhoea is assumed to be CS diarrhoea,consequences include uncontrolled diarrhoea,malnutrition,and perceived ineffectiveness of CS treatment.Approaches for facilitating differential diagnosis of diarrhoea include improving patient and clinician awareness of non-CS causes and involvement of a multidisciplinary clinical team,including gastroenterologists.CONCLUSION Diarrhoea in GEP-NETs can be multifactorial with misdiagnosis leading to delayed patient recovery and inefficient resource use.This systematic literature review highlights gaps for further research on prevalence of non-CS diarrhoea and suitability of diagnostic approaches,to determine an effective algorithm for differential diagnosis of GEP-NET diarrhoea. 相似文献
35.
Stepanova E. S. Makarenkova L. M. Chistyakov V. V. Rybakov Yu. L. Gukasov V. M. Fedotcheva T. A. Parshin V. A. Votyakov V. A. Shimanovskii N. L. 《Pharmaceutical Chemistry Journal》2019,52(12):1016-1020
Pharmaceutical Chemistry Journal - An HPLC-MS method for simultaneous quantitative determination of a novel gestagenic pharmaceutical and two of its metabolites in rat and rabbit blood sera was... 相似文献
36.
M.F. Werner A. López-Rueda F.X. Zarco J. Blasco L. San Román S. Amaro E. Carrero R. Valero L. Oleaga J.M. Macho N. Bargalló 《Radiologia》2019,61(2):143-152
Purpose
Endovascular treatment with mechanical thrombectomy devices demonstrated high recanalization rates but functional outcome did not correlate with high rates of recanalization obtained. Patient selection prior to the endovascular treatment is very important in the final outcome of the patient. The primary aim of our study was to evaluate the prognostic value of posterior circulation Alberta Stroke Program Early CT Score (pc-ASPECTS) and Pons-Midbrain Index (PMI) scores in patients with Basilar Artery Occlusion (BAO) treated with successful angiographic recanalization after mechanical thrombectomy.Methods
Retrospective single-center study including 18 patients between 2008 and 2013 who had acute basilar artery occlusion managed with endovascular treatment within 24 hours from symptoms onset and with successful angiographic recanalization. The patients were initially classified into two groups according to clinical outcome and mortality at 90 days. For analysis we also divided patients into groups based on pc-ASPECTS (≥8vs.< 8) and PMI (≥3vs.< 3) on non-contrast CT (NCCT) and CT Angiography Source Images (CTASI). Imaging data were correlated to clinical outcome and mortality rate.Results
CTASI pc-ASPECTS, dichotomized at < 8 versus≥8, was associated with a favorable outcome (RR: 2.6; 95% CI: 1.3-5.2) and a reduced risk of death (RR: 6.5: 95% CI: 7.8-23.3). All patients that survived and were functionally independent had pc-ASPECTS score≥8. None of the 5 patients with CTASI pc-ASPECTS score less than 8 survived.Conclusion
PC-ASPECTS on CTASI is helpful for predicting functional outcome after BAO recanalization with endovascular treatment. These results should be validated in a randomized controlled trial in order to decide whether or not to treat a patient with BAO. 相似文献37.
Jingjing He Lingyi Zhang Dan Guo Xingwen Han Hui Zhang Liang Wang Youcheng
Zhang 《Oncologie》2020,22(1):1-12
Hepatocellular carcinoma (HCC) ranks the sixth place of most common
cancers. Meanwhile, it is the tertiary mortality cause of cancer. There is no
effective therapeutic method to prevent and treat the liver cancer. Sinomenine is a
kind of Chinese traditional medicine herbal, it is reported that it can inhibit the
viability of several cancer cells. The study is to explore whether sinomenine is also
able to inhibit the cell viability of HCC and its potential mechanism. The IC50 of
sinomenine in BEL-7402 cells was 5.351 mmol/L, and the IC50 of sinomenine in
SMMC-7721 cells was 6.204 mmol/L. The gene expression results showed the
relative expression of FGF2, CCND2, DCN, F3, MMP7, NRG1, HMGB1,
TRIM29, HAS2, EHF, CTGF, PLK2 were down-regulated, and the relative
expression of VEGF A, CITED2, NUPR1, DDX58, IRF9, NAMPT, MMP1,
NDRG1, HMGA2, PPARGC1A, IFIT2, PARP9, HEY1, LOX, ETV1, ISG15,
BACH, CYLD were up-regulated. Moreover, the IPA analysis results suggested
that IFIT3, IFIT1, OAS1, MX1, IRF9, IFI6, IFITM1, ISG15 were up-regulated in
BEL-7402 cells treated with sinomenine by activating IFNA2. The findings
presented in this study may provide a promising method for the prevention and
treatment of liver cancer. 相似文献
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39.
Microglia, as the resident immune cells in the central nervous system, play important roles in regulating neuronal processes, such as neural excitability, synaptic activity, and apoptotic cell clearance. Growth factors can activate multiple signaling pathways in central nervous system microglia and can regulate their immune effects, but whether growth factors can affect the morphological characteristics and ultrastructure of microglia has not been reported. After microinjecting 300 nL of a growth factor cocktail, including 10 μg/mL epidermal growth factor, 10 μg/mL basic fibroblast growth factor, 10 μg/mL hepatocyte growth factor and 10 μg/mL insulin-like growth factor into adult rat cortex, we found that the number of IBA1-positive microglia around the injection area increased significantly, indicating local activation of microglia. All CD68-positive labeling co-localized with IBA1 in microglia. Cell bodies and protrusions of CD68-positive cells were strongly attached to or were engulfing neurons. Characteristic huge phagosomes were observed in activated phagocytes by electron microscopy. The phagosomes generally included non-degraded neuronal protrusions and mitochondria, yet they contained no myelin membrane or remnants, which might indicate selective phagocytosis by the phagocytes. The remnant myelin sheath after phagocytosis still had regenerative ability and formed "myelin-like" structures around phagocytes. These results show that microinjection of a growth factor cocktail into the cerebral cortex of rodents can locally activate microglia and induce selective phagocytosis of neural structures by phagocytes. The study was approved by the Institute of Laboratory Animal Science, Beijing Institute of Basic Medical Sciences(approval No. IACUC-AMMS-2014-501) on June 30, 2014. 相似文献
40.
Bo Cai Qiyun Sun Jianhui Qiao Changlin Yu Kaixun Hu Tieqiang Liu Bingxia Li Yajing Huang Yi Wang Hongli Zuo Zheng Dong Yaqing Lei Zhiqing Liu Bo Yao Caixia Li Huisheng Ai Mei Guo 《American journal of cancer research》2020,10(11):3852
Patients with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) have poor prognosis, and the efficacy of chemotherapy plus tyrosine kinase inhibitors (TKIs) followed by mismatched donor stem cell infusion (microtransplantation, MST) has not been determined. We retrospectively summarized 45 patients including 11 undergoing MST with TKIs, 17 receiving allogeneic transplant and 17 undergoing chemotherapy with TKIs. Improved 4-year overall survival rate was observed in the MST group (91%) compared with either transplant group (31%, P = .005) or chemotherapy group (36%, P = .013). The MST group also had higher 2-year and 4-year leukemia-free survival rates (91% and 72%, respectively) compared with either transplant group (33%, P = .005 and 33%, P = .021, respectively) or chemotherapy group (41%, P = .017 and 31%, P = .023, respectively). 2-year and 4-year cumulative incidences of hematologic relapse were lower in the MST group (9% and 28%, respectively) compared with those in the chemotherapy group (56%, P = .025 and 67%, P = .034, respectively). In patients undergoing MST, donor microchimerism was detected (1.07 × 10-5 to 6.6 × 10-4 copies from 9 to 1499 days) in 7 patients, and donor/patient-derived HLA*0201/2402+WT1+CD8+ T cells were found from 0.05% to 0.67% in 6 patients. MST may provide a favorable treatment for patients with Ph+ ALL. 相似文献