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81.
Mohana Krishna Reddy Mudiam Rajeev Jain Anshuman Singh Haider A. Khan Devendra Parmar 《Forensic Toxicology》2014,32(1):19-29
3-Phenoxybenzoic acid (3-PBA) and 4-hydroxy-3-phenoxybenzoic acid (OH-PBA) are the two common metabolites for most pyrethroid insecticides. A rapid, sensitive, and eco-friendly method has been developed based on ultrasound-assisted dispersive liquid–liquid microextraction (DLLME) coupled to large volume injection–gas chromatography–tandem mass spectrometry for the simultaneous determination of pyrethroid metabolites in rat brain treated with cypermethrin (CYP). Brain samples were homogenized in methanol (disperser solvent) followed by derivatization with methyl chloroformate (MCF) and extraction using DLLME. Factors that influence the extraction and derivatization efficiency such as type and volume of extraction and disperser solvent, sonication time, pH, ionic strength, and volumes of MCF and pyridine were optimized. Under optimized conditions, the limits of detection were 1 and 4 ng/g for 3-PBA and OH-PBA, respectively. Mean recoveries of pyrethroid metabolites in rat brain were in the range of 83–95 %. The developed method was successfully applied for determination of 3-PBA and OH-PBA in brain samples of CYP-treated rats. The developed method can be adopted for rapid and sensitive analysis of pyrethroid metabolites in toxicological and forensic laboratories. 相似文献
82.
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84.
Christopher C. Parker Sarah Pascoe Aleš Chodacki Joe M. O'Sullivan Josep R. Germá Charles Gillies O’Bryan-Tear Trond Haider Peter Hoskin 《European urology》2013
Background
Patients with castration-resistant prostate cancer (CRPC) and bone metastases have an unmet clinical need for effective treatments that improve quality of life and survival with a favorable safety profile.Objective
To prospectively evaluate the efficacy and safety of three different doses of radium chloride (Ra 223) in patients with CRPC and bone metastases.Design, setting, and participants
In this phase 2 double-blind multicenter study, 122 patients were randomized to receive three injections of Ra 223 at 6-wk intervals, at doses of 25 kBq/kg (n = 41), 50 kBq/kg (n = 39), or 80 kBq/kg (n = 42). The study compared the proportion of patients in each dose group who had a confirmed decrease of ≥50% in baseline prostate-specific antigen (PSA) levels.Outcome measurements and statistical analysis
Efficacy was evaluated using blood samples to measure PSA and other tumor markers, recorded skeletal-related events, and pain assessments. Safety was evaluated using adverse events (AEs), physical examination, and clinical laboratory tests. The Jonckheere-Terpstra test assessed trends between groups.Results and limitations
The study met its primary end point with a statistically significant dose–response relationship in confirmed ≥50% PSA declines for no patients (0%) in the 25-kBq/kg dose group, two patients (6%) in the 50-kBq/kg dose group, and five patients (13%) in the 80-kBq/kg dose group (p = 0.0297). A ≥50% decrease in bone alkaline phosphatase levels was identified in six patients (16%), 24 patients (67%), and 25 patients (66%) in the 25-, 50-, and 80-kBq/kg dose groups, respectively (p < 0.0001). The most common treatment-related AEs (≥10%) occurring up to week 24 across all dose groups were diarrhea (21%), nausea (16%), and anemia (14%). No difference in incidence of hematologic events was seen among dose groups. Potential limitations include small patient numbers and differences among dose groups at baseline.Conclusions
Ra 223 had a dose-dependent effect on serum markers of CRPC activity, suggesting that control of bone disease with Ra 223 may affect cancer-related outcomes. Ra 223 was well tolerated at all doses.Trial registration
ClinicalTrials.gov: NCT00337155. 相似文献85.
PD Dr. D. Stengel MSc A. Ekkernkamp E. Haider M. Frank J. Seifert 《Trauma und Berufskrankheit》2013,15(3):148-153
Clinical research—characteristics
Clinical research is a key component of developed health care systems, a major driving force of medical innovation, and, of course, an integral part of the German Federal Statutory Accident Insurance System. Specific institutions and well-trained experts are needed to cope with the rapidly emerging methodological, ethical, and administrative mandates of clinical research.Quality assurance and independence
Similar to other areas of health care, clinical research must demonstrate and maintain a high degree of structural and process quality. Yet, it can be shown that this increases the internal and external validity of research findings, as well as their likelihood of publication in renowned scientific journals. Apart from content validity, the relationship between individual investigators, their institutions, as well as public and commercial sponsors must be disclosed to maintain the integrity of research. 相似文献86.
Kothari N Keshari RS Bogra J Kohli M Abbas H Malik A Dikshit M Barthwal MK 《Journal of critical care》2011,26(4):435-435.e7
Introduction
Circulating lipopolysaccharides released from bacteria may activate both neutrophils and monocytes. The activated neutrophils release myeloperoxidase (MPO), a specific enzyme with strong oxidative activity. The aim of this study was to evaluate MPO enzyme activity in plasma of critically ill patients and to check the hypothesis that these concentrations in plasma would be higher in sepsis and systemic inflammatory conditions, as neutrophils release their contents before proliferating in response to stress.Material and Methods
Blood samples were collected from 105 critically ill patients admitted to the intensive care unit, consisting of those with systemic inflammatory response syndrome (n = 42), sepsis (n = 37), and septic shock (n = 26). Plasma MPO enzyme activity was determined by o-dianisidine-H2O2 method, modified for 96-well plates.Results
The plasma MPO enzyme activity in sepsis patients was significantly higher than that in the control group (mean, 2.4 ± 1.8 in sepsis and 1.86 ± 1.2 nmol per milligram protein per 10 minutes in systemic inflammatory response syndrome vs 0.32 ± 0.11 nmol per milligram protein per 10 minutes in healthy controls). Mean plasma lactate levels in sepsis (7.8 ± 1.2 mmol/L) and shock patients (9.5 ± 1.2 mmol/L) and cytokines like tumor necrosis factor–α, interleukin-8, and interleukin-1β were simultaneously evaluated to establish onset of inflammation and sepsis. These results show that neutrophil activation occurring during inflammation and sepsis could be detected by plasma MPO concentration.Conclusion
The plasma MPO concentrations may be a marker of the neutrophil proliferation and severity of inflammation. 相似文献87.
Wiegand PN Nathwani D Wilcox MH Stephens J Shelbaya A Haider S 《The Journal of hospital infection》2012,81(1):1-14
PubMed, EMBASE and conference abstracts were reviewed systematically to determine the clinical and economic burden associated with Clostridium difficile infection (CDI) acquired and treated in European healthcare facilities. Inclusion criteria were: published in the English language between 2000 and 2010, and study population of at least 20 patients with documented CDI acquired/treated in European healthcare facilities. Data collection was completed by three unblinded reviewers using the Cochrane Handbook and PRISMA statement. The primary outcomes were mortality, recurrence, length of hospital stay (LOS) and cost related to CDI. In total, 1138 primary articles and conference abstracts were identified, and this was narrowed to 39 and 30 studies, respectively. Data were available from 14 countries, with 47% of studies from UK institutions. CDI mortality at 30 days ranged from 2% (France) to 42% (UK). Mortality rates more than doubled from 1999 to 2004, and continued to rise until 2007 when reductions were noted in the UK. Recurrent CDI varied from 1% (France) to 36% (Ireland); however, recurrence definitions varied between studies. Median LOS ranged from eight days (Belgium) to 27 days (UK). The incremental cost of CDI was £4577 in Ireland and £8843 in Germany, after standardization to 2010 prices. Country-specific estimates, weighted by sample size, ranged from 2.8% to 29.8% for 30-day mortality and from 16 to 37 days for LOS. CDI burden in Europe was most commonly described using 30-day mortality, recurrence, LOS and cost data. The continued spread of CDI and resultant healthcare burden underscores the need for judicious use of antibiotics. 相似文献
88.
EB Schneider SA Hirani HL Hambridge ER Haut AR Carlini RC Castillo DT Efron AH Haider 《The Journal of surgical research》2012,177(2):295-300
BackgroundWeekend admission is associated with mortality in cardiovascular emergencies and stroke but the effect of weekend admission for trauma is not well defined. We sought to determine whether differences in mortality outcomes existed for older adults with substantial head trauma admitted on a weekday versus over the weekend.MethodsData from the 2006, 2007, and 2008 Nationwide Inpatient Sample were combined and head trauma admissions were isolated. Abbreviated injury scale (AIS) scores were calculated using ICDMAP-90 Software. Individuals aged 65 to 89 y with head AIS equal to 3 or 4 and no other region score <3 were included. Individual Charlson comorbidity scores were calculated and individuals with missing mortality, sex, or insurance data were excluded. Wilcoxon rank sum and Student t-tests compared demographics, length of stay, and total charges for weekday versus weekend admissions. The χ2 tests compared sex and head injury severity. Logistic regression modeled mortality adjusting for age, sex, injury severity, comorbidity, and insurance status.ResultsOf the 38,675 patients meeting criteria, 9937 (25.6%) were admitted on weekends. Mean age was similar (78.4 versus 78.4, P = 0.796) but more weekend admissions were female (51.6% versus 50.2%, P = 0.022). Weekend patients demonstrated slightly lower comorbidity (mean Charlson = 1.07 versus 1.14, P < 0.001) and head injury severity (58.3% versus 60.8% AIS = 4, P < 0.001). Median weekend length of stay was shorter (4 versus 5 d, P < 0.001). Weekend and weekday median total charges did not differ ($27,128 versus $27,703, respectively, P = 0.667). Proportional mortality was higher among weekend patients (9.3% versus 8.4%, P = 0.008). After adjustment, weekend patients demonstrated 14% increased odds of mortality (OR 1.14, 95% CI 1.05–1.23).ConclusionOlder adults with substantial head trauma admitted on weekends are less severely injured, carry less comorbidity, and generate similar total charges compared with those admitted on weekdays. However, after accounting for known risk confounders, weekend patients demonstrated 14% greater odds of mortality. Mechanisms behind this disparity must be determined and eliminated. 相似文献
89.
JG Crompton TA Oyetunji KM Pollack K Stevens EE Cornwell DT Efron ER Haut AH Haider 《Archives of surgery (Chicago, Ill. : 1960)》2012,147(7):674-676
Motorcycle collisions are increasing at a precipitous rate, and reliable and valid data regarding all aspects of helmet safety are needed to better inform ongoing debates on mandatory helmet laws. The objective of this study was to determine the effect of motorcycle helmets on the likelihood of a facial injury after motorcycle collisions, using data from the National Trauma Data Bank, version 7.0, on 46 362 patients from January 1, 2002, through December 31, 2006. Multiple logistic regression was used to analyze the independent association between helmets and facial injury with adjustment for potential confounders. Helmeted motorcyclists were less likely to suffer facial injuries after a motorcycle collision, with a lower adjusted odds ratio of facial injury (0.40; 95% CI, 0.37-0.43) and a lower prevalence of specific types of facial injury compared with their nonhelmeted counterparts. 相似文献
90.
Mentha species are used in every day life in various food items. These species produce valuable secondary metabolites that scavenge toxic free radicals. Toxic free radicals can cause different diseases in the human body. In the present study free radical scavenging potential (1,1-diphenyl-2-picrylhydrazyl scavenging activity) in nine Mentha species were investigated to evaluate and explore new potential sources for natural antioxidants. The activity was performed after different time intervals with incubation period of 30 minutes. The methanolic extracts revealed that significantly higher activity (82%) was observed in Mentha suaveolens, followed by Mentha longifolia (79%), Mentha officinalis (76%) and Mentha piperita, Mentha pulegium, Mentha royleana (75%), respectively. Significantly same activity was observed in Mentha arvensis and Mentha spicata. Lower activity was observed in Mentha citrata (64%). The present study revealed that these species can be used as natural antioxidants. 相似文献