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David M. Hurst Matthew E. Oster Sherry Smith Martha L. Clabby 《Pediatric cardiology》2015,36(7):1382-1385
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Brittany O. Dulmage Lisa Akintilo Leah J. Welty Matthew M. Davis Maria Colavincenzo Shuai Xu 《The American journal of medicine》2018,131(9):1130-1134.e6
IMPORTANCE
Residency applicants often use social media to discuss the positive and negative features of prospective training programs. An examination of the content discussed by applicants could provide guidance for how a medical education faculty can better engage with prospective trainees and adapt to meet the educational expectations of a new generation of digital-native physicians.OBJECTIVE
The objective was to identify unstructured social media data submitted by residency applicants and categorize positive and negative statements to determine key themes.DESIGN
The study design was qualitative analysis of a retrospective cohort.SETTING
Publicly available datasets were used.PARTICIPANTS
The participants were anonymized medical trainees applying to residency training positions in 9 specialties—dermatology, general surgery, internal medicine, obstetrics/gynecology, plastic surgery, otolaryngology, physical medicine and rehabilitation, pediatrics, and radiology—from 2007 to 2017.MAIN OUTCOMES AND MEASURES
After we developed a standardized coding scheme that broke comments down into major features, themes, and subthemes, all unstructured comments were coded by two independent researchers. Positive and negative comments were coded separately. Frequency counts and percentages were recorded for each identified feature, theme, and subtheme. The percent positive and negative comments by specialty were also calculated.RESULTS
: Of the 6314 comments identified, 4541 were positive and 1773 were negative. Institution was the most commonly cited major feature in both the positive (n?=?767 [17%]) and negative (n?=?827 [47%]) comments. Geography was the most cited theme, and City, Cost of Living, and Commute were commonly cited subthemes. Training was the next most cited major feature in both positive (n?=?1005 [22%]) and negative (n?=?291 [16%]) comments, with Clinical Training being more commonly cited compared to Research Opportunities. Overall, 72% of comments from all were positive; however, the percent of comments that were positive comments varied significantly across the 9 specialties. Pediatrics (65%), dermatology (66%), and internal medicine (68%) applicants were more likely to express negative comments compared with the global average, but physical medicine and rehabilitation (85%), radiology (82%), otolaryngology (81%), and plastic surgery (80%) applicants were more likely to express positive comments.CONCLUSIONS AND RELEVANCE
This qualitative analysis of positive and negative themes as posted by applicants in recent matching years is the first and provides new detailed insights into the motivations and desires of trainees. 相似文献997.
George E. A. Swann Virginia N. Panizzo Sebastiano Piccolroaz Vanessa Pashley Matthew S. A. Horstwood Sarah Roberts Elena Vologina Natalia Piotrowska Michael Sturm Andre Zhdanov Nikolay Granin Charlotte Norman Suzanne McGowan Anson W. Mackay 《Proceedings of the National Academy of Sciences of the United States of America》2020,117(44):27211
Lake Baikal, lying in a rift zone in southeastern Siberia, is the world''s oldest, deepest, and most voluminous lake that began to form over 30 million years ago. Cited as the “most outstanding example of a freshwater ecosystem” and designated a World Heritage Site in 1996 due to its high level of endemicity, the lake and its ecosystem have become increasingly threatened by both climate change and anthropogenic disturbance. Here, we present a record of nutrient cycling in the lake, derived from the silicon isotope composition of diatoms, which dominate aquatic primary productivity. Using historical records from the region, we assess the extent to which natural and anthropogenic factors have altered biogeochemical cycling in the lake over the last 2,000 y. We show that rates of nutrient supply from deep waters to the photic zone have dramatically increased since the mid-19th century in response to changing wind dynamics, reduced ice cover, and their associated impact on limnological processes in the lake. With stressors linked to untreated sewage and catchment development also now impacting the near-shore region of Lake Baikal, the resilience of the lake’s highly endemic ecosystem to ongoing and future disturbance is increasingly uncertain.Ancient lakes have long been associated with both high levels of biodiversity and endemicity. However, they are also being threatened by anthropogenic forcings that have led to impacts ranging from the warming of lake waters (1), hydrological modifications (2), increases in aquatic toxicity (3), and declining endemic populations due to introductions of nonnative species (4). With global populations increasingly reliant on large and ancient lakes for ecosystem services, the biodiversity (5) and value of aquatic systems to society (6), particularly in ancient lake systems (7), are at risk. Lake Baikal (Russia) is an exceptional example of an ancient lake (Fig. 1). In addition to containing ∼20% of global surface freshwater, the lake is characterized by its high degree of biodiversity with over 2,500 flora and fauna, the majority of which are endemic (8). This has been attributed to the lake’s age and fully oxygenated water column, driven by seasonal overturning and deep water renewal (9, 10) that sustains an almost completely endemic deep water fauna (8).Open in a separate windowFig. 1.Location of Lake Baikal and its catchment (gray) together with the location of World Meteorological Organization station in Irkutsk, major catchment rivers (brown), coring sites (BAIK13-1, BAIK13-4), and sites providing additional data used in this study (BAIK13-7).Concerns exist over the future health of this unique ecosystem, amid evidence of extensive shoreline eutrophication (11, 12) and climate-induced shifts in primary productivity (13, 14). Together, these changes have impacted organisms ranging from sponges and gastropods to ciliates, flagellates, and algal communities (15). Given the likelihood of future anthropogenic disturbance on Lake Baikal, further disrupting productivity exchanges through the lake’s food web, there is a need to place these contemporary observations into their historical setting. In Lake Baikal, we have evidence that algal communities have undergone rapid multidecadal to multicentennial timescale changes over the last 2,000 y (16). However, there is a need to also gain a clearer insight into how biogeochemical and nutrient cycling has altered over the same timescale, both to contextualize natural and anthropogenic drivers of change and to understand the susceptibility of the lake’s ecosystem to further alteration under different climate states (17). Annual primary productivity in Lake Baikal is ultimately regulated by photic zone nutrient availability, in addition to ice/snow cover, which regulates light availability for photosynthesis (10, 18). Here, by analyzing the silicon isotope composition of diatom silica (δ30Sidiatom), we show that nutrient supply to the surface waters of Lake Baikal has rapidly increased through the 20th and 21st centuries coincident with increased wind-driven Ekman transport and reduced ice cover. These changes in photic zone nutrient availability have the potential to alter resource competition and prey–predator interactions across the lake (15, 19). 相似文献
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Matthew E. Wand Kate S. Baker Gabriel Benthall Hannah McGregor James W. I. McCowen Ana Deheer-Graham J. Mark Sutton 《Antimicrobial agents and chemotherapy》2015,59(7):3966-3972
The EGD Murray collection consists of approximately 500 clinical bacterial isolates, mainly Enterobacteriaceae, isolated from around the world between 1917 and 1949. A number of these “Murray” isolates have subsequently been identified as Klebsiella pneumoniae. Antimicrobial susceptibility testing of these isolates showed that over 30% were resistant to penicillins due to the presence of diverse blaSHV β-lactamase genes. Analysis of susceptibility to skin antiseptics and triclosan showed that while the Murray isolates displayed a range of MIC/minimal bactericidal concentration (MBC) values, the mean MIC value was lower than that for more modern K. pneumoniae isolates tested. All Murray isolates contained the cation efflux gene cepA, which is involved in disinfectant resistance, but those that were more susceptible to chlorhexidine were found to have a 9- or 18-bp insertion in this gene. Susceptibility to other disinfectants, e.g., H2O2, in the Murray isolates was comparable to that in modern K. pneumoniae isolates. The Murray isolates were also less virulent in Galleria and had a different complement of putative virulence factors than the modern isolates, with the exception of an isolate related to the modern lineage CC23. More of the modern isolates (41% compared to 8%) are classified as good/very good biofilm formers, but there was overlap in the two populations. This study demonstrated that a significant proportion of the Murray Klebsiella isolates were resistant to penicillins before their routine use. This collection of pre-antibiotic era isolates may provide significant insights into adaptation in K. pneumoniae in relation to biocide susceptibility. 相似文献