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951.
Feedforward responses of transversus abdominis are directionally specific and act asymmetrically: implications for core stability theories 总被引:1,自引:0,他引:1
Allison GT Morris SL Lay B 《The Journal of orthopaedic and sports physical therapy》2008,38(5):228-237
STUDY DESIGN: Experimental laboratory study supplemented with a repeated case study. OBJECTIVE: To examine bilateral muscle activity of the deep abdominals in response to rapid arm raising, specifically to examine the laterality and directional specificity of feedforward responses of the transversus abdominis (TrA). BACKGROUND: Based on the feedforward responses of trunk muscles during rapid arm movements, authors have concluded that the deep trunk muscles have different control mechanisms compared to the more superficial muscles. It has been proposed that deep trunk muscles such as TrA contribute substantially to the stability of the lumbar spine and that this is achieved through simultaneous bilateral feedforward activation. These inferences are based on unilateral fine-wire electromyographic (EMG) data and there are limited investigations of bilateral responses of the TrA during unilateral arm raising. METHODS AND MEASURES: Bilateral fine-wire and surface EMG data from the anterior deltoid, TrA, obliquus internus (OI), obliquus externus, biceps femoris, erector spinae, and rectus abdominis during repeated arm raises were recorded at 2 kHz. EMG signal linear envelopes were synchronized to the onset of the anterior deltoid. A feedforward window was defined as the period up to 50 ms after the onset of the anterior deltoid, and paired onsets for bilateral muscles were plotted for both left and right arm movements. RESULTS: Trunk muscles from the group data demonstrated differences between sides (laterality), which were systematically altered when alternate arms were raised (directional specificity). This was clearly evident for the TrA but less obvious for the erector spinae. The ipsilateral biceps femoris and obliquus externus, and contralateral OI and TrA, were activated earlier than the alternate side for both right and left arm movements. This was a consistent pattern over a 7-year period for the case study. Data for the rectus abdominis derived from the case study demonstrated little laterality or directionally specific response. CONCLUSION: This is the first study to show that the feedforward activity of the TrA is specific to the direction of arm movement and not bilaterally symmetrical. The asymmetry of TrA activity during arm raising suggests that the interpretation of the role of TrA as a bilateral stabilizer during anticipatory postural adjustments needs to be revised. Future research needs to examine muscle synergies associated with the asymmetrical function of the TrA and the underlying mechanism associated with low-load stability training. LEVEL OF EVIDENCE: Therapy, level 5. 相似文献
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954.
Weng X Liu L Barcellos LF Allison JE Herrinton LJ 《The American journal of gastroenterology》2007,102(7):1429-1435
BACKGROUND AND AIMS: Previous studies provide evidence that some immune-mediated diseases occur at greater frequency among inflammatory bowel disease (IBD) patients than in the general population. The present study examined the co-occurrence of IBD with common immune-mediated disorders including asthma, psoriasis, type 1 diabetes, rheumatoid arthritis, multiple sclerosis, systemic lupus erythematosus, vitiligo, autoimmune thyroiditis (Grave's and Hashimoto's), and chronic glomerulonephritis. METHODS: We conducted a cross-sectional study among members of the Kaiser Permanente Medical Care Program for the period 1996-2005. A total of 12,601 patients with at least two IBD diagnoses in computerized visit data were ascertained. Four persons without IBD were matched to each IBD patient on age, gender, and length of enrollment. Information on co-occurring diseases was obtained from computerized visit data for 1996-2005. Conditional logistic regression was used to estimate the odds ratio and 95% confidence interval for the association of IBD with immune-mediated disorders after adjusting for smoking. RESULTS: Seventeen percent of the IBD patients and 10% of the persons without IBD had a diagnosis for at least one immune-mediated disease. IBD patients were more likely to have asthma (1.5, 95% CI 1.4-1.6), psoriasis (1.7, 95% CI 1.5-2.0), rheumatoid arthritis (1.9, 95% CI 1.5-2.3), and multiple sclerosis (2.3, 95% CI 1.6-3.3). CONCLUSIONS: Among the immune-mediated diseases we studied, most were more common in IBD patients than in persons without IBD, suggesting that IBD shares common etiologic factors with other immune-mediated diseases. 相似文献
955.
BACKGROUND: Approximately one-third of organ donors in the United States are trauma victims. In general, kidneys with large subcapsular hematomas are not used for transplant because of the possibility of significant parenchymal injury. A large subcapsular renal hematoma may cause scarring resulting in renal parenchymal compression and development of the Page syndrome. OBJECTIVE: To elucidate a successful method of evaluating kidneys subject to trauma, while also possibly preventing further damage and improving their function. DESIGN: Data were collected from the donor kidney pool of the New York Organ Donor Network from January 2006 through July 2007. Four kidneys during that period were determined to have significant subcapsular hematomas. Surgical intervention was undertaken and outcomes after transplantation were reviewed. MAIN OUTCOME MEASURES: Four of the kidneys underwent a surgical procedure to drain the subcapsular hematoma allowing assessment of the underlying renal parenchyma. All 4 of these kidneys were deemed transplantable. After transplantation, 3 of the 4 kidneys had immediate function and did not require dialysis. The remaining kidney was removed as a result of primary nonfunction. CONCLUSION: The described surgical intervention allows the transplant surgeon to accurately assess the extent of damage to a traumatized kidney while possibly preventing further damage to the kidney. 相似文献
956.
Background In the United States, post-mastectomy breast reconstruction is a state (all 51 jurisdictions) and federally mandated benefit.
Outpatient mastectomy, which could lower use of breast reconstruction, may raise concerns about whether patients receive adequate
post-mastectomy care.
Methods Using linked surveillance, epidemiology, and end results (SEER)–Medicare data, we identified Medicare fee-for-service women
aged 65–69 years, diagnosed with early-stage breast cancer, and receiving unilateral mastectomy from 1998–2002. The corresponding
surgery delivery settings were determined from claims data. The outcome of interest was reconstruction within 4 months of
diagnosis. We used multivariable logistic regression models to examine the association of outpatient mastectomy with the likelihood
of post-mastectomy reconstruction, controlling for patient’s characteristics.
Results Among the 3,419 patients in the sample, 717 (21%) patients received outpatient mastectomy. The proportions of patients receiving
reconstruction were 13% for inpatient mastectomy patients and 4% for outpatient mastectomy patients. Outpatient mastectomy
patients were younger and had less comorbidities than inpatient mastectomy patients. Multivariable regression analysis suggested
that outpatient mastectomy patients were less likely to receive reconstruction (odds ratio = 0.247; 95% confidence interval
(CI): 0.166–0.368). Additional analysis suggests that African American patients were less likely than white patients to undergo
reconstruction (odds ratio = 0.515; 95% CI: 0.293–0.906) and that this ethnic difference was more manifest among patients
undergoing inpatient mastectomies.
Conclusions This study shows that outpatient mastectomy was associated with lower use of breast reconstruction. A better understanding
of choice of delivery setting of mastectomy with a focus on younger and minority breast cancer patients should be explored
in future research. 相似文献
957.
Waters AM Mogg K Bradley BP Pine DS 《Journal of the American Academy of Child and Adolescent Psychiatry》2008,47(4):435-442
ObjectiveTo examine attentional bias for angry and happy faces in 7- to 12-year-old children with generalized anxiety disorder (GAD; n = 23) and nonanxious controls (n = 25).MethodChildren completed a visual probe task in which pairs of face stimuli were displayed for 500 milliseconds and were replaced by a visual probe in the spatial location of one of the faces.ResultsSeverely anxious children with GAD showed an attentional bias toward both angry and happy faces. Children with GAD with a milder level of anxiety and nonanxious controls did not show an attentional bias toward emotional faces. Moreover, within the GAD group, attentional bias for angry faces was associated with increased anxiety severity and the presence of social phobia.ConclusionsBiased attention toward threat as a function of increased severity in pediatric GAD may reflect differing threat appraisal processes or emotion regulation strategies. 相似文献
958.
Some of the most complex auditory neurons known are found in the songbird forebrain, throughout the 'song system', including its basal ganglia nucleus Area X. These cells are selective for the temporal order of the bird's own song (BOS): they typically respond strongly to BOS, but more weakly when the syllable sequence of BOS is played in reverse order (roBOS), indicating that they integrate auditory information over more than single syllables. Here, studying the zebra finch Area X, we found that order selectivity strongly depends on the mean syllable duration of individual songs, decreasing markedly as this duration approaches 150–200 ms. Simply segmenting the same songs differently, creating an increase in average syllable length towards 150 ms, caused a similar decrease in order selectivity. This suggests that song neurons integrate acoustic information over a relatively limited time window, predominantly less than 150 ms. We provided further support for this by showing that a significant fraction of Area X order selectivity was accounted for by the acoustic similarity between each BOS and roBOS, measured using cross-correlation with fixed window sizes, but only when the correlation windows were at least 50 ms and no more than 200 ms long. All the same findings were evident in birds raised without tutor exposure, indicating that tutor learning has little effect on neural mechanisms underlying song temporal selectivity. Our results suggest that song-selective neurons encode much of the temporal context of song using a short, constant time window that is conserved across differences in songs, birds and learning. 相似文献
959.
Choledochojejunostomy is commonly performed for biliary bypass for benign and malignant disease. Anastomotic stricture is a known complication of enteric surgery. We report the use of the laparoscopic linear cutter at laparotomy to revise a choledochojejunostomy created 12 years previously for benign disease. 相似文献
960.
A patient admitted repetitively for vomiting was found to have a radiologic abnormality in the lesser sac, initially interpreted as a pancreatic mass. At exploration, intestinal obstruction due to transmesocolonic herniation of the jejunum explained both the symptoms and the radiologic finding. 相似文献