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11.
In this paper, we develop and study numerical methods for the two-mode shallow water equations recently proposed in [S. STECHMANN, A. MAJDA, and B. KHOUIDER, Theor. Comput. Fluid Dynamics, 22 (2008), pp. 407–432]. Designing a reliable numerical method for this system is a challenging task due to its conditional hyperbolicity and the presence of nonconservative terms. We present several numerical approaches–two operator splitting methods (based on either Roe-type upwind or central-upwind scheme), a central-upwind scheme and a path-conservative central-upwind scheme– and test their performance in a number of numerical experiments. The obtained results demonstrate that a careful numerical treatment of nonconservative terms is crucial for designing a robust and highly accurate numerical method.  相似文献   
12.
A FRAX® model for Romania calibrated to the total Romanian population was released June 1, 2011. This article describes the data used to develop the Romanian FRAX model and illustrates its features compared to models for other countries. Age- and sex-stratified hip fracture incidence rates and mortality rates for 2010 were extracted from nationwide databases from the age of 40 years. For other major fractures, Romanian incidence rates were imputed, using Swedish ratios for hip to other major osteoporotic fracture (humerus, forearm, and clinically symptomatic vertebral fractures). Fracture incidence rates increased with increasing age: for hip fracture, incidence rates were higher among younger men than women but with a female preponderance from the age of 65 years. The 10-year probability of hip or major fracture was increased in patients with a clinical risk factor (CRF), lower BMI, female gender, higher age, and decreased BMD T score. Of the CRFs, a parental hip fracture accounted for the greatest increase in 10-year fracture probability. The Romanian FRAX tool is the first country-specific fracture prediction model. It is based on the original FRAX methodology, which has been externally validated in several independent cohorts. Despite some limitations, the strengths make the Romanian FRAX tool a good candidate for implementation into clinical practice.  相似文献   
13.
Fibroblast growth factor‐23 (FGF23) is a bone‐derived hormone regulating vitamin D hormone production and renal handling of minerals by signaling through an FGF receptor/αKlotho (Klotho) receptor complex. Whether Klotho has FGF23‐independent effects on mineral homeostasis is a controversial issue. Here, we aimed to shed more light on this controversy by comparing male and female triple knockout mice with simultaneous deficiency in Fgf23 and Klotho and a nonfunctioning vitamin D receptor (VDR) (Fgf23/Klotho/VDR) with double (Fgf23/VDR, Klotho/VDR, and Fgf23/Klotho) and single Fgf23, Klotho, and VDR mutants. As expected, 4‐week‐old Fgf23, Klotho, and Fgf23/Klotho knockout mice were hypercalcemic and hyperphosphatemic, whereas VDR, Fgf23/VDR, and Klotho/VDR mice on rescue diet were normocalcemic and normophosphatemic. Serum levels of calcium, phosphate, and sodium did not differ between 4‐week‐old triple Fgf23/Klotho/VDR and double Fgf23/VDR or Klotho/VDR knockout mice. Notably, 3‐month‐old Fgf23/Klotho/VDR triple knockout mice were indistinguishable from double Fgf23/VDR and Klotho/VDR compound mutants in terms of serum calcium, serum phosphate, serum sodium, and serum PTH, as well as urinary calcium and sodium excretion. Protein expression analysis revealed increased membrane abundance of sodium‐phosphate co‐transporter 2a (NaPi‐2a), and decreased expression of sodium‐chloride co‐transporter (NCC) and transient receptor potential cation channel subfamily V member 5 (TRPV5) in Fgf23/Klotho/VDR, Fgf23/VDR, and Klotho/VDR mice, relative to wild‐type and VDR mice, but no differences between triple and double knockouts. Further, ex vivo treatment of live kidney slices isolated from wild‐type and Klotho/VDR mice with soluble Klotho did not induce changes in intracellular phosphate, calcium or sodium accumulation assessed by two‐photon microscopy. In conclusion, our data suggest that the main physiological function of Klotho for mineral homeostasis in vivo is its role as co‐receptor mediating Fgf23 action. © 2017 American Society for Bone and Mineral Research.  相似文献   
14.

Aims

Central venous catheters are essential for the management of pediatric cardiac surgery patients. Recently, an ultrasound-guided access via a supraclavicular approach to the brachiocephalic vein has been described. Central venous catheters are associated with a relevant number of complications in pediatric patients. In this study, we evaluated the frequency of complications of left brachiocephalic vein access compared with right internal jugular vein standard access in children undergoing cardiac surgery.

Methods

Retrospective analysis of all pediatric cases at our tertiary care university hospital over a two-year period receiving central venous catheters for cardiac surgery. Primary endpoint: Frequency of complications associated with central venous catheters inserted via the left brachiocephalic vein vs. right internal jugular vein. Complications were defined as: chylothorax, deep vein thrombosis, sepsis, or delayed chest closure. Secondary endpoints: Evaluation of the insertion depth of the catheter using a height-based formula without adjustment for side used.

Results

Initially, 504 placed catheters were identified. Following inclusion and exclusion criteria, 480 placed catheters remained for final analysis. Overall complications were reported in 68/480 (14.2%) cases. There was no difference in the frequency of all complications in the left brachiocephalic vein vs. the right internal jugular vein group (15.49% vs. 13.65%; OR = 1.16 [0.64; 2.07]), nor was there any difference considering the most relevant complications chylothorax (7.7% vs. 8.6%; OR = 0.89 [0.39; 1.91]) and thrombosis (5.6% vs. 4.5%; OR = 1.28 [0.46; 3.31]). The mean deviation from the optimal insertion depth was left brachiocephalic vein vs. right internal jugular vein 5.38 ± 13.6 mm and 4.94 ± 15.1 mm, respectively.

Conclusions

Among children undergoing cardiac surgery, there is no significant difference between the supraclavicular approach to the left brachiocephalic vein and the right internal jugular vein regarding complications. For both approaches, a universal formula can be used to determine the correct insertion depth.  相似文献   
15.
PURPOSE: Assessment of TTT results in patients with exudative age-related macular degeneration. MATERIAL AND METHODS: The study comprised of 65 patients (73 eyes), in age 50-84 years (average age-75 yrs). The diagnosis of exudative AMD was established on the basis of fundus examination and fluorescein angiography (FA) and in some cases on indocyanine green angiography. The baseline visual acuity (VA) ranged from counting fingers at 50 cm to 0.8. In 31 (42.5%) eyes occult CNV, in 11 (15%) minimally classic CNV and in 31 (42.5%) eyes predominantly classic CNV were observed. Subfoveal CNV was present in 70 (95.9%) eyes and perifoveal in 3 (4.1%). TTT was delivered using a diode laser at 810 nm wavelength, a spot size of 1.2 to 4.5 mm and a duration of 60 seconds for each spot with power settings between 320-800 mW. Follow-up examinations were carried out every 10-12 weeks. In cases with persistent leakage from CNV in late frames of FA a retreatment was performed. The follow-up period ranged from 6 to 28 months (average - 9.8 months). RESULTS: Visual acuity improved in 22 (30.1%) eyes, stabilized in 34 (46.6%) and deteriorated in 17 (23.3%). Fluorescein angiography showed no CNV leakage in 58 (79.5%) eyes. In 56 (71.8%) with regression of leakage in fluorescein angiography improvement or stabilization of visual acuity was detected. Subretinal haemorrhages after TTT were observed in 4 eyes (5.5%). At the end of the follow-up period fibrosis of CNV was detected in 12 eyes (16.4%). CONCLUSIONS: TTT is effective and safe method of treatment of occult and classic CNV in a course of wet AMD. In a majority of cases TTT results in total or partial regression of CNV and stabilization of visual acuity.  相似文献   
16.
17.
OBJECTIVE: To compare maximum oxygen uptake and anaerobic threshold in patients with fibromyalgia (FM) and healthy sedentary controls matched by sex, age, weight, and body mass index. METHODS: Fifty women with FM aged 18-60 years and 50 healthy sedentary controls were studied. All were submitted to a maximum treadmill incremental test. Expired gas, ventilatory anaerobic threshold, and maximum oxygen uptake (VO2max) were evaluated. The influence of FM on quality of life was evaluated by questionnaires: the Fibromyalgia Impact Questionnaire and the Medical Outcomes Study Short-Form (SF-36). RESULTS: In patients with FM, the anaerobic threshold and peak oxygen uptake were significantly reduced. Maximum heartbeat rate was significantly lower in FM, indicating submaximum effort. Linear regression data showed a correlation between peak VO2 and the "Role-physical" domain of the SF-36. No such correlations were noted with anaerobic threshold. CONCLUSION: These results confirm the hypothesis of lower physical fitness in patients with FM. Considering that patients with FM do not achieve a maximum effort, ventilatory anaerobic threshold should be considered as a better fitness index than VO2max.  相似文献   
18.
The improvement in sickle cell disease (SCD) children receiving cromolyn sodium therapy prompted us to investigate its antisickling activity in vitro . The number of sickle cells was determined in deoxygenated blood samples from 15 children with severe SCD. At the eight concentrations tested, cromolyn sodium exhibited a significantly higher activity than pentoxifylline, the standard compound. Therefore cromolyn sodium would appear to be an interesting candidate for SCD therapy and deserves further in vivo investigations.  相似文献   
19.
Inflammation Research - Despite the long belief that the role of the adipose tissue was restricted to that of a passive store of triglycerides and a rich source of fatty acids, accumulating data...  相似文献   
20.
Better understanding of the effects of growth on children’s bones and cartilage is necessary for clinical and biomechanical purposes. The aim of this study is to define the 3D geometry of children’s rib cages: including sternum, ribs and costal cartilage. Three-dimensional reconstructions of 960 ribs, 518 costal cartilages and 113 sternebrae were performed on thoracic CT scans of 48 children, aged 4 months to 15 years. The geometry of the sternum was detailed and nine parameters were used to describe the ribs and rib cages. A “costal index” was defined as the ratio between cartilage length and whole rib length to evaluate the cartilage ratio for each rib level. For all children, the costal index decreased from rib level 1 to 3 and increased from level 3 to 7. For all levels, the cartilage accounted for 45–60 % of the rib length, and was longer for the first years of life. The mean costal index decreased by 21 % for subjects over 3-year old compared to those under three (p < 10?4). The volume of the sternebrae was found to be highly age dependent. Such data could be useful to define the standard geometry of the pediatric thorax and help to detect clinical abnormalities.  相似文献   
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