全文获取类型
收费全文 | 3920篇 |
免费 | 224篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 33篇 |
儿科学 | 191篇 |
妇产科学 | 85篇 |
基础医学 | 524篇 |
口腔科学 | 31篇 |
临床医学 | 270篇 |
内科学 | 783篇 |
皮肤病学 | 64篇 |
神经病学 | 247篇 |
特种医学 | 102篇 |
外科学 | 413篇 |
综合类 | 234篇 |
一般理论 | 5篇 |
预防医学 | 333篇 |
眼科学 | 89篇 |
药学 | 323篇 |
中国医学 | 72篇 |
肿瘤学 | 354篇 |
出版年
2023年 | 27篇 |
2022年 | 61篇 |
2021年 | 120篇 |
2020年 | 56篇 |
2019年 | 71篇 |
2018年 | 79篇 |
2017年 | 74篇 |
2016年 | 89篇 |
2015年 | 99篇 |
2014年 | 126篇 |
2013年 | 172篇 |
2012年 | 260篇 |
2011年 | 244篇 |
2010年 | 155篇 |
2009年 | 126篇 |
2008年 | 181篇 |
2007年 | 196篇 |
2006年 | 176篇 |
2005年 | 171篇 |
2004年 | 156篇 |
2003年 | 162篇 |
2002年 | 117篇 |
2001年 | 100篇 |
2000年 | 94篇 |
1999年 | 76篇 |
1998年 | 32篇 |
1997年 | 25篇 |
1996年 | 26篇 |
1994年 | 22篇 |
1993年 | 22篇 |
1992年 | 64篇 |
1991年 | 57篇 |
1990年 | 49篇 |
1989年 | 46篇 |
1988年 | 45篇 |
1987年 | 31篇 |
1986年 | 44篇 |
1985年 | 41篇 |
1984年 | 23篇 |
1983年 | 25篇 |
1979年 | 29篇 |
1977年 | 20篇 |
1976年 | 19篇 |
1975年 | 22篇 |
1974年 | 20篇 |
1973年 | 31篇 |
1972年 | 36篇 |
1971年 | 23篇 |
1970年 | 27篇 |
1968年 | 26篇 |
排序方式: 共有4153条查询结果,搜索用时 15 毫秒
961.
The MinC component of the division site selection system in Escherichia coli interacts with FtsZ to prevent polymerization
下载免费PDF全文
![点击此处可从《Proceedings of the National Academy of Sciences of the United States of America》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Hu Z Mukherjee A Pichoff S Lutkenhaus J 《Proceedings of the National Academy of Sciences of the United States of America》1999,96(26):14819-14824
Positioning of the Z ring at the midcell site in Escherichia coli is assured by the min system, which masks polar sites through topological regulation of MinC, an inhibitor of division. To study how MinC inhibits division, we have generated a MalE-MinC fusion that retains full biological activity. We find that MalE-MinC interacts with FtsZ and prevents polymerization without inhibiting FtsZ's GTPase activity. MalE-MinC19 has reduced ability to inhibit division, reduced affinity for FtsZ, and reduced ability to inhibit FtsZ polymerization. These results, along with MinC localization, suggest that MinC rapidly oscillates between the poles of the cell to destabilize FtsZ filaments that have formed before they mature into polar Z rings. 相似文献
962.
963.
Dopamine D3 receptor binding of 18F‐fallypride: Evaluation using in vitro and in vivo PET imaging studies
下载免费PDF全文
![点击此处可从《Synapse (New York, N.Y.)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Jogeshwar Mukherjee Cristian C. Constantinescu Angela T. Hoang Taleen Jerjian Divya Majji Min‐Liang Pan 《Synapse (New York, N.Y.)》2015,69(12):577-591
Identification of dopamine D3 receptors (D3R) in vivo is important to understand several brain functions related to addiction. The goal of this work was to identify D3R binding of the dopamine D2 receptor (D2R)/D3R imaging agent, 18F‐fallypride. Brain slices from male Sprague‐Dawley rats (n = 6) and New Zealand White rabbits (n = 6) were incubated with 18F‐fallypride and D3R selective agonist (R)‐7‐OH‐DPAT (98‐fold D3R selective). Rat slices were also treated with BP 897 (68‐fold D3R selective partial agonist) and NGB 2904 (56‐fold D3R selective antagonist). In vivo rat studies (n = 6) were done on Inveon PET using 18‐37 MBq 18F‐fallypride and drug‐induced displacement by (R)‐7‐OH‐DPAT, BP 897 and NGB 2904. PET/CT imaging of wild type (WT, n = 2) and D2R knock‐out (KO, n = 2) mice were carried out with 18F‐fallypride. (R)‐7‐OH‐DPAT displaced binding of 18F‐fallypride, both in vitro and in vivo. In vitro, at 10 nM (R)‐7‐OH‐DPAT, 18F‐fallypride binding in the rat ventral striatum (VST) and dorsal striatum (DST) and rabbit nucleus accumbens were reduced by ~10–15%. At 10 μM (R)‐7‐OH‐DPAT all regions in rat and rabbit were reduced by ≥85%. In vivo reductions for DST and VST before and after (R)‐7‐OH‐DPAT were: low‐dose (0.015 mg kg?1) DST ?22%, VST ?29%; high‐dose (1.88 mg kg?1) DST ?58%, VST ?77%, suggesting D3R/D2R displacement. BP 897 and NGB 2904 competed with 18F‐fallypride in vitro, but unlike BP 897, NGB 2904 did not displace 18F‐fallypride in vivo. The D2R KO mice lacked 18F‐fallypride binding in the DST. In summary, our findings suggest that up to 20% of 18F‐fallypride may be bound to D3R sites in vivo. Synapse 69:577–591, 2015 . © 2015 Wiley Periodicals, Inc. 相似文献
964.
SCAI/AATS/ACC/STS operator and institutional requirements for transcatheter valve repair and replacement,Part III: Pulmonic valve
下载免费PDF全文
![点击此处可从《Catheterization and cardiovascular interventions》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Ziyad M. Hijazi MD MPH Carlos E. Ruiz MD PhD Evan Zahn MD Richard Ringel MD Gabriel S. Aldea MD Emile A. Bacha MD Joseph Bavaria MD R. Morton Bolman MD III Duke E. Cameron MD Larry S. Dean MD Ted Feldman MD David Fullerton MD Eric Horlick MDCM Michael J. Mack MD D. Craig Miller MD Marc R. Moon MD Debabrata Mukherjee MD Alfredo Trento MD Carl L. Tommaso MD 《Catheterization and cardiovascular interventions》2015,86(1):85-93
With the evolution of transcatheter valve replacement, an important opportunity has arisen for cardiologists and surgeons to collaborate in identifying the criteria for performing these procedures. Therefore, The Society for Cardiovascular Angiography and Interventions (SCAI), American Association for Thoracic Surgery (AATS), American College of Cardiology (ACC), and The Society of Thoracic Surgeons (STS) have partnered to provide recommendations for institutions to assess their potential for instituting and/or maintaining a transcatheter valve program. This article concerns transcatheter pulmonic valve replacement (tPVR). tPVR procedures are in their infancy with few reports available on which to base an expert consensus statement. Therefore, many of these recommendations are based on expert consensus and the few reports available. As the procedures evolve, technology advances, experience grows, and more data accumulate, there will certainly be a need to update this consensus statement. The writing committee and participating societies believe that the recommendations in this report serve as appropriate requisites. In some ways, these recommendations apply to institutions more than to individuals. There is a strong consensus that these new valve therapies are best performed using a Heart Team approach; thus, these credentialing criteria should be applied at the institutional level. Partnering societies used the ACC's policy on relationships with industry (RWI) and other entities to author this document ( http://www.acc.org/guidelines/about-guidelines-and-clinical-documents ). To avoid actual, potential, or perceived conflicts of interest due to industry relationships or personal interests, all members of the writing committee, as well as peer reviewers of the document, were asked to disclose all current healthcare‐related relationships including those existing 12 months before the initiation of the writing effort. A committee of interventional cardiologists and surgeons was formed to include a majority of members with no relevant RWI and to be led by an interventional cardiology cochair and a surgical cochair with no relevant RWI. Authors with relevant RWI were not permitted to draft or vote on text or recommendations pertaining to their RWI. RWI were reviewed on all conference calls and updated as changes occurred. Author and peer reviewer RWI pertinent to this document are disclosed in the Appendices. In addition, to ensure complete transparency, authors' comprehensive disclosure information (including RWI not pertinent to this document) is available in Appendix AII. The work of the writing committee was supported exclusively by the partnering societies without commercial support. SCAI, AATS, ACC, and STS believe that adherence to these recommendations will maximize the chances that these therapies will become a successful part of the armamentarium for treating valvular heart disease in the United States. In addition, these recommendations will hopefully facilitate optimum quality during the delivery of this therapy, which will be important to the development and successful implementation of future, less invasive approaches to structural heart disease. 相似文献
965.
S. Datta S. Mitra P. Chattopadhyay T. Som S. Mukherjee S. Basu 《European journal of clinical microbiology & infectious diseases》2017,36(2):255-265
To investigate the mobilizable elements associated with bla NDM-1 in Enterobacteriaceae isolated from septicaemic neonates at a NICU in India, during December, 2008–2011. An attempt was also made to understand whether there was a pattern in the temporal acquisition of bla NDM-1 within the unit. Transferability of carbapenem resistance was tested by conjugation and transformation. Plasmid types and addiction systems were analysed. The genetic background of bla NDM-1 and association with class 1 integron were evaluated by PCR mapping. RFLP was carried out to discriminate plasmids of same incompatibility group. Transfer of carbapenem resistance was successful in 13/15 cases. bla NDM-1 was associated with different plasmid scaffolds (IncFII, IncL/M, IncN, IncR, IncHIB-M/FIB-M), IncF type being the prevalent one. Addiction systems ccdAB and hok/sok were associated with transferable plasmids. Genetic structures surrounding bla NDM-1 showed its association with at least a remnant of ISAba125 at its 5′-end. The spread of NDM-1 was not related to class 1 integron which possessed resistance determinants against trimethoprim (dfrA12, dfrA1, dfrA5), streptomycin (aadA2, aacA4), and rifampicin (arr-3). RFLP showed that three isolates possessed the same FII/FIIs plasmid; two of these three isolates were from a single neonate, implying interspecies transfer of bla NDM-1. The predominance of FII plasmids and ISAba125 along with bla NDM-1 was noted, but no specific pattern in the temporal acquisition of mobile genetic elements could be identified. To the best of our knowledge, this report is the first to inform the in-vivo interspecies plasmid transfer event of bla NDM-1 in a neonate. 相似文献
966.
Joshua D. Dowell Sugoto Mukherjee Prashant Raghavan Patrice K. Rehm 《Journal of neuroimaging》2015,25(6):1047-1049
Granulomatous amebic encephalitis (GAE) is a rare and oftentimes fatal disease in immune compromised patients caused by free living amebae Acanthamoeba and Balamuthia. We report a patient in whom GAE secondary to Acanthamoeba was the initial presentation of acquired immunodeficiency syndrome in a 41‐year‐old male, and discuss the FDG positron emission tomography (PET) and magnetic resonance imaging findings that preceded the pathological diagnosis. The PET results provided complementary information when coupled with the MR brain findings. Improved understanding of the clinical and imaging findings of this deadly disease is the best hope for early diagnosis and treatment of this uncommon but deadly disease. 相似文献
967.
968.
Sukhendu Sarkhel Sailendra Bhattacharyya Somnath Mukherjee 《Indian Journal of Orthopaedics》2015,49(5):523-528
Background:
The condyles of the distal humerus have characteristic orientation in reference to the diaphysis. Anatomical reduction of the articular surface in intraarticular fractures of adult distal humerus does not always restore preinjury functional status. The purpose of this study was to determine the outcome of treating these fractures with technique of condylar orientation precontoured plating. The principle of the technique is to primarily restore the anatomical orientation of the reconstructed distal humeral condyle with the diaphysis of the humerus apart from anatomical reduction of fracture.Materials and Methods:
Seventy one consecutive patients with comminuted intraarticular adult distal humerus fractures were treated with the condylar orientation plates, which were specifically designed between 1999 and 2009. 43 fractures were Association for osteosynthesis (AO) type C3, 24 were C2 and 4 were C1. Six were open cases and two were of nonunion distal end humerus. On medial and posterolateral side of the distal humerus, precontoured Sherman plates were applied. Patients were followed up for a mean of 3 years. They were assessed clinically (using mayo elbow performance score [MEPS]) and radio-graphically.Results:
Sixty (84.5%) patients regained MEPS of 90 or more that is an excellent result (range of movement and functional status). One patient had nonunion with implant failure, and two patients developed heterotopic ossification. The mean MEPS was 95. Average extension and flexion was 15° and 133°. The result was graded as excellent in 60, good in 7, fair in 3 and poor in 1. At the time of most recent followup, 63 elbows were painless, and eight had mild pain.Conclusion:
Excellent pain free range of motion with a high rate of union can be achieved in comminuted intraarticular distal humerus fractures in adults with the use of condylar orientation precontoured plating technique. Condylar orientation is very important with perfect articular congruity in elbow motion. 相似文献969.
Madhumita?MukhopadhyayEmail author Sankar?Das?Chattopadhyay Nisith?Chandra?Karmakar Rina?Mukherjee Partha?Sarathi?Ghosh Krishna?Pada?Rakshit Sanjay?Kumar?Mondal Soumya?Ghoshal 《Hellēnikē cheirourgikē. Acta chirurgica Hellenica》2015,87(4):342-344
Aim
To report the rare case of a primary peritoneal hydatid cyst in a 65-year-old lady.Case Report
A 65-year-old female presented with a 3-month history of a painless progressive swelling in the right lower abdomen. The lump was 10 cm × 8 cm in size, non-tender, cystic in consistency, and was located in the right iliac fossa and part of the right lumbar region; mobility was restricted in all directions. CECT showed a large septated cystic lesion 14 × 9 × 8 cm in size with enhancement, and sharp regular outline in the right lower abdomen along the anterior aspect of the right psoas muscle. The liver and spleen were not affected.Result
During surgery, a cystic swelling was exposed. Aspiration revealed a clear fluid with some floating material. The cyst wall was incised and fluid along with daughter cysts were removed keeping the pericyst in situ. Histopathological examination confirmed hydatid disease.Conclusion
Primary peritoneal hydatid cysts, though very rare, should be kept in mind in the differential diagnosis of a right iliac fossa lump in areas where hydatid disease is endemic.970.
Anand Ajmera Ankit Verma Mukul Agrawal Saurabh Jain Arunangshu Mukherjee 《Indian Journal of Orthopaedics》2015,49(4):429-435
Background:Management of open tibial diaphyseal fractures with bone loss is a matter of debate. The treatment options range from external fixators, nailing, ring fixators or grafting with or without plastic reconstruction. All the procedures have their own set of complications, like acute docking problems, shortening, difficulty in soft tissue management, chronic infection, increased morbidity, multiple surgeries, longer hospital stay, mal union, nonunion and higher patient dissatisfaction. We evaluated the outcome of the limb reconstruction system (LRS) in the treatment of open fractures of tibial diaphysis with bone loss as a definative mode of treatment to achieve union, as well as limb lengthening, simultaneously.Results:Mean followup period was 15 months. The mean bone loss was 5.5 cm (range 4-9 cm). The mean duration of bone transport was 13 weeks (range 8-30 weeks) with a mean time for LRS in place was 44 weeks (range 24-51 weeks). The mean implant index was 56.4 days/cm. Mean union time was 52 weeks (range 31-60 weeks) with mean union index of 74.5 days/cm. Bony results as per the ASAMI scoring were excellent in 76% (19/25), good in 12% (3/25) and fair in 4% (1/25) with union in all except 2 patients, which showed poor results (8%) with only 2 patients having leg length discrepancy more than 2.5 cm. Functional results were excellent in 84% (21/25), good in 8% (2/25), fair in 8% (2/25). Pin tract infection was seen in 5 cases, out of which 4 being superficial, which healed to dressings and antibiotics. One patient had a deep infection which required frame removal.Conclusion:Limb reconstruction system proved to be an effective modality of treatment in cases of open fractures of the tibia with bone loss as definite modality of treatment for damage control as well as for achieving union and lengthening, simultaneously, with the advantage of early union with attainment of limb length, simple surgical technique, minimal invasive, high patient compliance, easy wound management, lesser hospitalization and the lower rate of complications like infection, deformity or shortening. 相似文献