全文获取类型
收费全文 | 23665篇 |
免费 | 1796篇 |
国内免费 | 77篇 |
专业分类
耳鼻咽喉 | 394篇 |
儿科学 | 813篇 |
妇产科学 | 375篇 |
基础医学 | 2425篇 |
口腔科学 | 524篇 |
临床医学 | 2155篇 |
内科学 | 5213篇 |
皮肤病学 | 547篇 |
神经病学 | 1275篇 |
特种医学 | 1117篇 |
外国民族医学 | 1篇 |
外科学 | 4545篇 |
综合类 | 325篇 |
一般理论 | 15篇 |
预防医学 | 1153篇 |
眼科学 | 822篇 |
药学 | 2040篇 |
中国医学 | 38篇 |
肿瘤学 | 1761篇 |
出版年
2023年 | 223篇 |
2022年 | 401篇 |
2021年 | 985篇 |
2020年 | 473篇 |
2019年 | 814篇 |
2018年 | 947篇 |
2017年 | 610篇 |
2016年 | 646篇 |
2015年 | 672篇 |
2014年 | 1012篇 |
2013年 | 1180篇 |
2012年 | 1742篇 |
2011年 | 1710篇 |
2010年 | 869篇 |
2009年 | 812篇 |
2008年 | 1282篇 |
2007年 | 1210篇 |
2006年 | 1127篇 |
2005年 | 979篇 |
2004年 | 883篇 |
2003年 | 754篇 |
2002年 | 648篇 |
2001年 | 586篇 |
2000年 | 550篇 |
1999年 | 490篇 |
1998年 | 160篇 |
1997年 | 135篇 |
1996年 | 138篇 |
1995年 | 142篇 |
1994年 | 113篇 |
1993年 | 97篇 |
1992年 | 267篇 |
1991年 | 284篇 |
1990年 | 248篇 |
1989年 | 212篇 |
1988年 | 208篇 |
1987年 | 219篇 |
1986年 | 192篇 |
1985年 | 177篇 |
1984年 | 111篇 |
1983年 | 126篇 |
1982年 | 85篇 |
1981年 | 70篇 |
1979年 | 129篇 |
1978年 | 77篇 |
1977年 | 69篇 |
1975年 | 58篇 |
1974年 | 65篇 |
1973年 | 88篇 |
1970年 | 58篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
151.
152.
153.
Dipesh E. Patel Phillippa M. Cumberland Bronwen C. Walters Joseph Abbott John Brookes Beth Edmunds Peng Tee Khaw Ian Christopher Lloyd Maria Papadopoulos Velota Sung Mario Cortina-Borja Jugnoo S. Rahi For the OPTIC Study Group 《Eye (London, England)》2022,36(6):1281
BackgroundPerimetry is important in the management of children with glaucoma, but there is limited evidence-based guidance on its use. We report an expert consensus-based study to update guidance and identify areas requiring further research.MethodsExperts were invited to participate in a modified Delphi consensus process. Panel selection was based on clinical experience of managing children with glaucoma and UK-based training to minimise diversity of view due to healthcare setting. Questionnaires were delivered electronically, and analysed to establish ‘agreement’. Divergence of opinions was investigated and resolved where possible through further iterations.Results7/9 experts invited agreed to participate. Consensus (≥5/7 (71%) in agreement) was achieved for 21/26 (80.8%) items in 2 rounds, generating recommendations to start perimetry from approximately 7 years of age (IQR: 6.75–7.25), and use qualitative methods in conjunction with automated reliability indices to assess test quality. There was a lack of agreement about defining progressive visual field (VF) loss and methods for implementing perimetry longitudinally.Panel members highlighted the importance of informing decisions based upon individual circumstances—from gauging maturity/capability when selecting tests and interpreting outcomes, to accounting for specific clinical features (e.g. poor IOP control and/or suspected progressive VF loss) when making decisions about frequency of testing.ConclusionsThere is commonality of expert views in relation to implementing perimetry and interpreting test quality in the management of children with glaucoma. However, there remains a lack of agreement about defining progressive VF loss, and utilising perimetry over an individuals’ lifetime, highlighting the need for further research.Subject terms: Paediatrics, Glaucoma 相似文献
154.
Jennifer R. Brown John C. Byrd Paolo Ghia Jeff P. Sharman Peter Hillmen Deborah M. Stephens Clare Sun Wojciech Jurczak John M. Pagel Alessandra Ferrajoli Priti Patel Lin Tao Nataliya Kuptsova-Clarkson Javid Moslehi Richard R. Furman 《Haematologica》2022,107(6):1335
Cardiovascular (CV) toxicities of the Bruton tyrosine kinase (BTK) inhibitor ibrutinib may limit use of this effective therapy in patients with chronic lymphocytic leukemia (CLL). Acalabrutinib is a second-generation BTK inhibitor with greater BTK selectivity. This analysis characterizes pooled CV adverse events (AE) data in patients with CLL who received acalabrutinib monotherapy in clinical trials (clinicaltrials gov. Identifier: , NCT02029443, NCT02475681 and NCT02970318). Acalabrutinib was given orally at total daily doses of 100–400 mg, later switched to 100 mg twice daily, and continued until disease progression or toxicity. Data from 762 patients (median age: 67 years [range, 32–89]; median follow-up: 25.9 months [range, 0–58.5]) were analyzed. Cardiac AE of any grade were reported in 129 patients (17%; grade ≥3, n=37 [5%]) and led to treatment discontinuation in seven patients (1%). The most common any-grade cardiac AE were atrial fibrillation/flutter (5%), palpitations (3%), and tachycardia (2%). Overall, 91% of patients with cardiac AE had CV risk factors before acalabrutinib treatment. Among 38 patients with atrial fibrillation/flutter events, seven (18%) had prior history of arrhythmia or atrial fibrillation/flutter. Hypertension AE were reported in 67 patients (9%), 43 (64%) of whom had a preexisting history of hypertension; no patients discontinued treatment due to hypertension. No sudden cardiac deaths were reported. Overall, these data demonstrate a low incidence of new-onset cardiac AE with acalabrutinib in patients with CLL. Findings from the head-to-head, randomized trial of ibrutinib and acalabrutinib in patients with high-risk CLL (clinicaltrials gov. Identifier: NCT02337829) prospectively assess differences in CV toxicity between the two agents. NCT02477696相似文献
155.
156.
Payank Patel Amit Roy Navid Sharifi Pantcho Stoyanov Richard R. Chromik Christian Moreau 《Materials》2022,15(10)
Surface coatings that operate effectively at elevated temperatures provide compatibility with critical service conditions as well as improved tribological performance of the components. High-entropy coatings (HECs), including metallic, ceramics, and composites, have gained attention all over the world and developed rapidly over the past 18 years, due to their excellent mechanical and tribological properties. High-entropy alloys (HEAs) are defined as alloys containing five or more principal elements in equal or close to equal atomic percentage. Owing to the high configurational entropy compared to conventional alloys, HEAs are usually composed of a simple solid solution phase, such as the BCC and FCC phases, instead of complex, brittle intermetallic phases. Several researchers have investigated the mechanical, oxidation, corrosion and wear properties of high-entropy oxides, carbides, borides, and silicates using various coating and testing techniques. More recently, the friction and wear characteristics of high-entropy coatings (HECs) have gained interest within various industrial sectors, mainly due to their favourable mechanical and tribological properties at high temperatures. In this review article, the authors identified the research studies and developments in high-entropy coatings (HECs) fabricated on various substrate materials using different synthesis methods. In addition, the current understanding of the HECs characteristics is critically reviewed, including the fabrication routes of targets/feedstock, synthesis methods utilized in various research studies, microstructural and tribological behaviour from room temperature to high temperatures. 相似文献
157.
J M Patel 《Toxicology》1987,45(1):79-91
Cyclophosphamide (CP) causes lung toxicity in a wide variety of animals including humans. Recent reports suggest that CP increases lipid peroxide formation in the lung, and that oxygen (O2) potentiates CP-induced lung toxicity. We hypothesized that CP, or one of its toxic metabolites, acrolein, stimulates lung lipid peroxide formation in the presence of high O2 tensions. To test this, rat lung microsomes were treated in vitro with CP or acrolein in the presence of NADPH and 0-100% O2 with and without superoxide dismutase (SOD), glutathione (GSH), dithiothreitol (DTT), and EDTA (agents which scavenge reactive O2 species and/or detoxify reactive metabolites). Lipid peroxide formation in untreated microsomes was increased 40, 39, and 37% in 60, 80 and 100% O2 respectively (P less than 0.02 vs. 21% O2 air). Lipid peroxide formation in microsomes treated with CP increased 2-3-fold under 21% O2 (P less than 0.05 vs. untreated under 21% O2). However, increases in lipid peroxide formation were 3-4 fold in CP treated microsomes under 40-100% O2 (P less than 0.001 vs. untreated at same % O2). CP and acrolein-stimulated lipid peroxidation with and without O2 exposure was significantly (P less than 0.05) reduced by prior addition of SOD, GSH, DTT, or EDTA to the lung microsomal suspension. These results indicate that lipid peroxide formation increases in CP and acrolein-treated lung microsomes, and high O2 tensions stimulate CP-induced lipid peroxidation. Stimulation of CP-induced microsomal lipid peroxidation appears to be mediated by reactive O2 species or metabolites. 相似文献
158.
Rahul V. Patel Premlata Kumari Dhanji P. Rajani Kishor H. Chikhalia 《Medicinal chemistry research》2012,21(12):4177-4192
A series of 2-(4-cyano-3-trifluoromethylphenyl amino)-4-(4-quinazolinyloxy)-6-piperazinyl(piperidinyl)-s-triazines have been synthesized in this study by a simple and efficient synthetic protocol. The synthetic route to final piperazinyl s-triazines involved two nucleophilic substitution reactions of 4-amino-2-trifluoromethyl-benzonitrile and 4-hydroxyquinazoline with 2,4,6-trichloro-1,3,5-triazine resulting in 2,4-disubstituted-6-chloro-1,3,5-triazine derivative to introduce the piperazinyl or piperidinyl functionality. The structures of the compounds were elucidated with the aid of IR, 1H NMR, 13C NMR, 19F NMR spectroscopy, and elemental analysis. The antimicrobial activity of the compounds was tested against eight bacteria (Staphylococcus aureus MTCC 96, Bacillus cereus MTCC 619, Escherichia coli MTCC 739, Pseudomonas aeruginosa MTCC 741, Klebsiella pneumoniae MTCC 109, Salmonella typhi MTCC 733, Proteus vulgaris MTCC 1771, Shigella Flexneria MTCC 1457) and four fungi (Aspergillus niger MTCC 282, Aspergillus fumigatus MTCC 343, Aspergillus clavatus MTCC 1323, and Candida albicans MTCC 183). The title compounds were also investigated for their antituberculosis activity against MTB H37 RV strain using BACTEC MGIT and L. J. agar dilution method. The bioassay results showed that compounds 5d, 5n, 5p, 5s, and 5t demonstrated 99% inhibition at the MIC of 6.25?μg/ml, equivalent to standard drug pyrazinamide. 相似文献
159.
Bhakti Gajjar Sanjay Sharma Erum Khan Pranita Sharma Pawan Jain Vikas Goel Arvind Neral Jyotish Patel Mamta Parmar Kanika Sharma Vijay K. Sharma Arvind K. Sharma 《Medicine》2022,101(27)
India has the second highest number of cases of sickle cell disease (SCD) and affects the most socioeconomically disadvantaged communities living in a horizontal belt from Gujarat to Odisha state. Despite high prevalence, information about cerebral hemodynamics among children with SCD in India remains scarcely described.We performed transcranial Doppler (TCD) to assess cerebral hemodynamics among Indian children with SCD and evaluated their association with clinical and hematological parameters.Children aged 3-18years, diagnosed with SCD living in Raipur in Chhattisgarh and Ahmedabad in Gujarat state were recruited. TCD was performed to obtain flow velocities from middle cerebral (MCA), intracranial internal carotid (ICA) and basilar artery. Associations were evaluated between timed-average-mean-maximum velocities (TAMMV) and various clinical and hematological parameters.Our prospective study included 62 consecutive children with known SCD. Mean ± SD age of the study population was 9.8 ± 3.9 years and 31 (50%) were male. Mean ± SD hemoglobin was 8.64 ± 1.34 Gm/dL while the mean HbSS ± SD was 70.25 ± 15.27%. While 6 (9.6%) children had suffered from stroke during previous 2 years, 7 (11%) demonstrated abnormal TAMMV. Higher HbSS level along with history of iron chelation therapy, blood transfusion and/or stroke showed a trend towards having higher TAMMV.Stroke and cerebral hemodynamic alterations are common among Indian children with SCD. Larger studies with detailed neuroimaging and genetic evaluations are needed for better understanding, characterization, risk stratification as well as optimization of the timing of blood transfusion to reduce physical disabilities among Indian children with SCD. 相似文献
160.
Sreeneeranj Kasichayanula Sandhya Mandlekar Vittal Shivva Maulik Patel Sandhya Girish 《CTS Clinical and Translational Science》2022,15(8):1818
Cancer immunotherapy has significantly advanced the treatment paradigm in oncology, with approvals of immuno‐oncology agents for over 16 indications, many of them first line. Checkpoint inhibitors (CPIs) are recognized as an essential backbone for a successful anticancer therapy regimen. This review focuses on the US Food and Drug Administration (FDA) regulatory approvals of major CPIs and the evolution of translational advances since their first approval close to a decade ago. In addition, critical preclinical and clinical pharmacology considerations, an overview of the pharmacokinetic and dose/regimen aspects, and a discussion of the future of CPI translational and clinical pharmacology as combination therapy becomes a mainstay of industrial immunotherapy development and in clinical practice are also discussed. 相似文献