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31.
Alexander J. Pappas Kyle E. Haffner Samuel S. Mendicino 《The Journal of foot and ankle surgery》2013,52(4):470-474
The posterior tibial tendon transfer through the interosseous membrane, as popularized by Watkins in 1954, is a procedure for treating reducible eversion and dorsiflexory paresis used by lower extremity foot and ankle surgeons. The posterior tibial tendon has been transferred to various locations on the midfoot for equinus and equinovarus deformities. Dorsiflexory paresis is a common symptom in equinovarus deformity, clubfoot deformity, Charcot-Marie-Tooth disease, leprosy, mononeuropathy, trauma to the common peroneal nerve, cerebrovascular accident, and Duchenne's muscular dystrophy. The main difficulty with this procedure, often discussed by surgeons, is inadequate tendon length, making anchoring to the cuneiforms or cuboid difficult. The goal of our cadaveric study was threefold. First, we sought to determine whether the tendon length is sufficient when transferring the posterior tibial tendon to the dorsum of the foot through the interosseous membrane for a dynamic or a static transfer. Second, we wished to describe the surgical technique designed to obtain the maximal length. Finally, we sought to discuss the strategies used when the tendon length for transfer is insufficient. 相似文献
32.
Unique white matter microstructural patterns in ADHD presentations—a diffusion tensor imaging study 下载免费PDF全文
Alena Svatkova Igor Nestrasil Kyle Rudser Jodene Goldenring Fine Jesse Bledsoe Margaret Semrud‐Clikeman 《Human brain mapping》2016,37(9):3323-3336
Attention‐deficit/hyperactivity disorder predominantly inattentive (ADHD‐PI) and combined (ADHD‐C) presentations are likely distinct disorders that differ neuroanatomically, neurochemically, and neuropsychologically. However, to date, little is known about specific white matter (WM) regions differentiating ADHD presentations. This study examined differences in WM microstructure using diffusion tensor imaging (DTI) data from 20 ADHD‐PI, 18 ADHD‐C, and 27 typically developed children. Voxel‐wise analysis of DTI measurements in major fiber bundles was carried out using tract‐based spatial statistics (TBSS). Clusters showing diffusivity abnormalities were used as regions of interest for regression analysis between fractional anisotropy (FA) and neuropsychological outcomes. Compared to neurotypicals, ADHD‐PI children showed higher FA in the anterior thalamic radiations (ATR), bilateral inferior longitudinal fasciculus (ILF), and in the left corticospinal tract (CST). In contrast, the ADHD‐C group exhibited higher FA in the bilateral cingulum bundle (CB). In the ADHD‐PI group, differences in FA in the left ILF and ATR were accompanied by axial diffusivity (AD) abnormalities. In addition, the ADHD‐PI group exhibited atypical mean diffusivity in the forceps minor (FMi) and left ATR and AD differences in right CB compared to healthy subjects. Direct comparison between ADHD presentations demonstrated radial diffusivity differences in FMi. WM clusters with FA irregularities in ADHD were associated with neurobehavioral performance across groups. In conclusion, differences in WM microstructure in ADHD presentations strengthen the theory that ADHD‐PI and ADHD‐C are two distinct disorders. Regions with WM irregularity seen in both ADHD presentations might serve as predictors of executive and behavioral functioning across groups. Hum Brain Mapp 37:3323–3336, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
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34.
Kenneth David Illingworth Youssef El Bitar Kyle Siewert Steven L. Scaife Saadiq El-Amin Khaled J. Saleh 《Knee surgery, sports traumatology, arthroscopy》2014,22(7):1649-1658
Purpose
The purpose of this study was to determine the correlation between the Western Ontario and McMasters Universities Osteoarthritis Index (WOMAC) and Knee Injury Osteoarthritis Outcomes scores (KOOS) and the degree of tibiofemoral cartilage loss on plain radiography and 3T magnetic resonance imaging (MRI). We hypothesize that these subjective outcome scores will have a significant correlation to quantitative joint space loss.Methods
Data used in the preparation of this article were obtained from the osteoarthritis initiative (OAI) database (OAI public use data sets kMRI_QCart_Eckstein18 and kXR_QJSW_Duryea16). Four hundred and forty-five patients had WOMAC/KOOS scores, quantitative tibiofemoral joints space width on plain radiographs and quantitative tibiofemoral cartilage thickness and per cent full thickness cartilage loss on 3T MRI. Joint space width on plain radiographs was correlated to cartilage thickness on MRI, and WOMAC/KOOS scores were correlated to the degree of cartilage loss using Pearson correlation coefficients.Results
There was a statistically significant correlation between medial and lateral compartment cartilage thickness on MRI and medial and lateral joint space width on plain radiography (r = 0.86, r = 0.80) (p < 0.001). KOOS knee pain score was significantly correlated to increasing per cent full thickness cartilage loss in the medial femoral compartment (r = 0.34) (p < 0.001). KOOS symptom score was significantly correlated to decreasing joint space width in the medial (r = 0.16) and lateral (r = 0.15) compartment and increasing per cent full thickness cartilage loss in the medial femoral compartment (r = 0.36) (p < 0.001). No WOMAC score was correlated to degree of joint space width, cartilage thickness or per cent full thickness cartilage loss (n.s).Conclusion
The WOMAC and KOOS scores are poor indicators of tibiofemoral cartilage loss, with only the KOOS symptom and knee pain score being weakly correlated. Osteoarthritis is a multifactorial process and the need to treat patients based off their symptoms and rely on radiographs as confirmatory modalities, and not diagnostic modalities, when talking about OA and medical intervention.Level of evidence
Level 2. 相似文献35.
Daniel Rios Kyle S. Jansson Frank Martetschläger Robert E. Boykin Peter J. Millett Coen A. Wijdicks 《Knee surgery, sports traumatology, arthroscopy》2014,22(2):442-447
Purpose
The purpose of this study was to quantitatively measure the morphology of the glenoid and to assess feasibility of using the medial tibial plateau surface as a donor for osteoarticular allograft reconstruction of the glenoid.Methods
Using computed tomography (CT), 10 tibias and 10 scapular models from our database (5 males and 5 females in each group) were randomly selected. Commercial software (Mimics, Materialize, Inc., Plymouth, MI) was used to extract the bone contours from the CT images and to reconstruct the 3-dimensional (3D) geometry of the scapula and tibia. By utilizing the software Creo Elements/Pro 5.0 (Parametric Technology Corp., Needham, MA), mean length and width of both the glenoid and medial tibial plateau were calculated. Radius of curvature was then measured in each 3D CT model at three intermediate segment points that were established within the length line at 25, 50, and 75 percent from superior to inferior in the glenoid and from posterior to anterior in the medial tibial plateau. Statistical analysis was performed and determined to be significant for P < 0.05.Results
The mean (±SD) radius of curvature values at the established 25, 50, and 75 percent segments of the glenoid were 47.4 ± 17.5 mm, 51.2 ± 12.4 mm, and 45.9 ± 17.0 mm, respectively. For the medial tibial plateau, the radius of curvature at 25, 50, and 75 percent were 43.5 ± 9.7 mm, 37.4 ± 14.3 mm and 52.3 ± 21.5 mm, respectively. Values of the glenoid length were 34.0 ± 2.9 mm, and width values were 24.4 ± 2.3 mm. For the medial tibial plateau, the length was 42.6 ± 2.7 mm, and the width was 23.3 ± 4.3 mm. There was no statistical difference in the radius of curvature and dimensional surface area between the glenoid and medial tibial plateau surfaces.Conclusion
The 3D CT-based anatomic study found that there is a statistically similar relationship in the radius of curvature of the glenoid and the medial tibial plateau surface. This concept may allow the medial tibial plateau to be used as a donor for osteoarticular allograft reconstruction of the glenoid, especially in young patients where previous studies have demonstrated that the success rate in shoulder replacements is not as good as in older patients. 相似文献36.
Sean D. Smith Coen A. Wijdicks Kyle S. Jansson Robert E. Boykin Frank Martetschlaeger Peter-Paul de Meijer Peter J. Millett Tom R. Hackett 《Knee surgery, sports traumatology, arthroscopy》2014,22(2):448-455
Purpose
Operative treatment for middle-third clavicle fractures has been increasing as recent data has demonstrated growing patient dissatisfaction and functional deficits after non-operative management. A controlled biomechanical comparison of the characteristics of locked intramedullary (IM) fixation versus superior pre-contoured plating for fracture repair and hardware removal is warranted. Therefore, the purpose of the present study was to investigate potential differences between these devices in a biomechanical model.Methods
Thirty fourth-generation composite clavicles were randomized to one of five groups with 6 specimens each and tested in a random order. The groups tested were intact, repair with plate, repair with IM device, plate removal, and IM device removal. The lateral end of the clavicles was loaded to failure at a rate of 60 mm/min in a cantilever bending setup. Failure mechanism, energy (J), and torque (Nm) at the site of failure were recorded.Results
Failure torque of the intact clavicle (mean ± standard deviation) was 36.5 ± 7.3 Nm. Failure torques of the IM repair (21.5 ± 9.0 Nm) and plate repair (18.2 ± 1.6 Nm) were not significantly different (n.s.) but were significantly less than the intact group (P < 0.05). Failure torque following IM device removal (30.2 ± 6.5 Nm) was significantly greater than plate removal (12.9 ± 2.0 Nm) (P < 0.05). No significant differences were observed between the intact and IM device removal groups (n.s.).Conclusion
The results of the current study demonstrate that IM and plate devices provide similar repair strength for middle-third clavicle fractures. However, testing of the hardware removal groups found the IM device removal group to be significantly stronger than the plate removal group. 相似文献37.
Watts LM Manchem VP Leedom TA Rivard AL McKay RA Bao D Neroladakis T Monia BP Bodenmiller DM Cao JX Zhang HY Cox AL Jacobs SJ Michael MD Sloop KW Bhanot S 《Diabetes》2005,54(6):1846-1853
Glucocorticoids (GCs) increase hepatic gluconeogenesis and play an important role in the regulation of hepatic glucose output. Whereas systemic GC inhibition can alleviate hyperglycemia in rodents and humans, it results in adrenal insufficiency and stimulation of the hypothalamic-pituitary-adrenal axis. In the present study, we used optimized antisense oligonucleotides (ASOs) to cause selective reduction of the glucocorticoid receptor (GCCR) in liver and white adipose tissue (WAT) and evaluated the resultant changes in glucose and lipid metabolism in several rodent models of diabetes. Treatment of ob/ob mice with GCCR ASOs for 4 weeks resulted in approximately 75 and approximately 40% reduction in GCCR mRNA expression in liver and WAT, respectively. This was accompanied by approximately 65% decrease in fed and approximately 30% decrease in fasted glucose levels, a 60% decrease in plasma insulin concentration, and approximately 20 and 35% decrease in plasma resistin and tumor necrosis factor-alpha levels, respectively. Furthermore, GCCR ASO reduced hepatic glucose production and inhibited hepatic gluconeogenesis in liver slices from basal and dexamethasone-treated animals. In db/db mice, a similar reduction in GCCR expression caused approximately 40% decrease in fed and fasted glucose levels and approximately 50% reduction in plasma triglycerides. In ZDF and high-fat diet-fed streptozotocin-treated (HFD-STZ) rats, GCCR ASO treatment caused approximately 60% reduction in GCCR expression in the liver and WAT, which was accompanied by a 40-70% decrease in fasted glucose levels and a robust reduction in plasma triglyceride, cholesterol, and free fatty acids. No change in circulating corticosterone levels was seen in any model after GCCR ASO treatment. To further demonstrate that GCCR ASO does not cause systemic GC antagonism, normal Sprague-Dawley rats were challenged with dexamethasone after treating with GCCR ASO. Dexamethasone increased the expression of GC-responsive genes such as PEPCK in the liver and decreased circulating lymphocytes. GCCR ASO treatment completely inhibited the increase in dexamethasone-induced PEPCK expression in the liver without causing any change in the dexamethasone-induced lymphopenia. These studies demonstrate that tissue-selective GCCR antagonism with ASOs may be a viable therapeutic strategy for the treatment of the metabolic syndrome. 相似文献
38.
Walsh DS Thavichaigarn P Pattanapanyasat K Siritongtaworn P Kongcharoen P Tongtawe P Yongvanitchit K Jiarakul N Dheeradhada C Pearce FJ Wiesmann WP Webster HK 《The Journal of surgical research》2005,129(2):221-230
BACKGROUND: Severe injury is associated with changes in monocytes that may contribute to poor outcomes. Longitudinal characterization of monocyte response patterns after trauma may provide added insight into these immunological alterations. METHODS: Venous blood obtained seven times during post-injury days 1 through 13 from 61 patients with an injury severity score >20 was assessed by flow cytometry for monocytes (CD14+) expressing HLA-DR or CD71 (transferrin receptor) and for circulating levels of interleukin (IL) 1alpha, IL-1beta, IL-6, soluble CD14 (sCD14), tumor necrosis factor-alpha (TNF-alpha), prostaglandin E(2) (PGE(2)), thromboxane B(2) (TXB(2)), and endotoxin. Urine neopterin was measured by high-pressure liquid chromatography, expressed as a neopterin-creatinine ratio. RESULTS: Trauma patients had leucocytosis days 1 through 13, monocytosis days 5 through 13, reduced proportions of CD14+HLA-DR+ cells days 2 through 5, and elevated proportions of CD14+CD71+ cells days 1 through 13. Neopterin was elevated all days, peaking on day 10. sCD14 was elevated days 2 through 13, and there were sporadic elevations of IL-1alpha, IL-1beta, IL-6, TNF-alpha, PGE(2), TXB(2), and endotoxin. Sepsis syndrome patients (n = 6) had larger and more prolonged reductions in CD14+HLA-DR+ cells and higher neopterin values, in comparison with uneventful patient outcomes. CONCLUSIONS: Altered proportions of monocytes expressing HLA-DR and CD71 and elevated sCD14 and urine neopterin levels, for up to 2 weeks after severe injury, underscores an extended period of profound immunological effects. Additional studies to more fully assess temporal monocyte response patterns after severe injury, including activation, may be warranted. 相似文献
39.
John C. Morrison Kyle Steffen Blake Pantoja Asha Nagaiya Jacek Kobus & Thomas Ericsson 《Communications In Computational Physics》2016,19(3):632-647
In order to solve the partial differential equations that arise in the Hartree-Fock
theory for diatomic molecules and in molecular theories that include electron correlation,
one needs efficient methods for solving partial differential equations. In this
article, we present numerical results for a two-variable model problem of the kind that
arises when one solves the Hartree-Fock equations for a diatomic molecule. We compare
results obtained using the spline collocation and domain decomposition methods
with third-order Hermite splines to results obtained using the more-established finite
difference approximation and the successive over-relaxation method. The theory of
domain decomposition presented earlier is extended to treat regions that are divided
into an arbitrary number of subregions by families of lines parallel to the two coordinate
axes. While the domain decomposition method and the finite difference approach
both yield results at the micro-Hartree level, the finite difference approach with a 9-point difference formula produces the same level of accuracy with fewer points. The
domain decomposition method has the strength that it can be applied to problems with
a large number of grid points. The time required to solve a partial differential equation
for a fine grid with a large number of points goes down as the number of partitions
increases. The reason for this is that the length of time necessary for solving a set of
linear equations in each subregion is very much dependent upon the number of equations.
Even though a finer partition of the region has more subregions, the time for
solving the set of linear equations in each subregion is very much smaller. This feature
of the theory may well prove to be a decisive factor for solving the two-electron pair
equation, which – for a diatomic molecule – involves solving partial differential equations
with five independent variables. The domain decomposition theory also makes
it possible to study complex molecules by dividing them into smaller fragments thatare calculated independently. Since the domain decomposition approach makes it possible
to decompose the variable space into separate regions in which the equations are
solved independently, this approach is well-suited to parallel computing. 相似文献
40.
Kyle P. Harvey M.D. James D. Adair M.D. Mayyas Isho M.D. Robert Robinson M.D. F.A.C.S. 《American journal of surgery》2009,198(2):231-236