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91.
92.
BACKGROUND: The coexistence of peripheral artery disease (PAD) and multilevel atherosclerosis increases death and stroke rates in patients with coronary artery disease (CAD). Due to many comorbidities these patients are often treated conservatively without revascularisation. AIM: To investigate whether complex percutaneous cardiovascular interventions for CAD and PAD may improve prognosis and long-term outcome in this group of patients. METHODS: We studied consecutive patients treated for symptomatic CAD who also had chronic PAD. The primary cause of hospital admission for all our patients was non-ST elevation acute coronary syndrome (NSTE ACS). All percutaneous peripheral interventions were performed during one hospital stay (index hospitalisation). Major adverse cardio- and cerebrovascular events (MACCE) during follow-up were defined as follows: death (cardiac and non-cardiac), myocardial infarction (MI), urgent revascularisation (surgical or repeat PCI, peripheral percutaneous intervention), stroke/TIA or amputation. RESULTS: We performed 109 interventions in 78 consecutive patients with chronic peripheral artery stenoses and occlusions. The average age was 61.5+/-8.6 years and the majority were males (80%). Preinterventional angiography showed occlusions that involved the common iliac artery in 28 (36%) patients, the external iliac artery in 16 (21%) patients, internal iliac artery in 2 (3%) patients, and superficial femoral artery in 63 (81%) patients. Stenting was performed in half of the patients with a mean stent length of 69.6+/-50.3 mm. An average number of 1.24+/-0.55 stents was used for each lesion. During a mean follow-up of 18 months (range 4 to 42), there were 4 deaths, 3 MIs, 13 repeated percutaneous peripheral interventions due to restenosis in previously treated peripheral lesions, two urgent coronary interventions, two ischaemic strokes, two TIAs and one amputation. The combined follow--up MACCE end-point occurred in 32% of patients. CONCLUSIONS: Patients with concomitant CAD and PAD could safely undergo percutaneous cardiovascular and peripheral interventions. Multilevel intervention is associated with a promising long-term follow-up.  相似文献   
93.
94.

Introduction

Statin use might be associated with an increased risk of sleep disturbances including insomnia, but the evidence regarding sleep changes following statin therapy has not been conclusive. Therefore we assessed the impact of statin therapy on sleep changes through a systematic review and meta-analysis of available randomized controlled trials (RCTs).

Material and methods

We searched MEDLINE and SCOPUS up to October 1, 2014 to identify placebo-controlled RCTs investigating the effect of statin therapy on sleep changes. A meta-analysis was performed using either a fixed-effects or a random-effect model according to the I2 statistic. Effect size was expressed as weighted mean difference (WMD) and 95% confidence interval (CI).

Results

Overall, the impact of statin therapy on polysomnography (PSG) indices of sleep was reported in 5 trials comprising 9 treatment arms. Overall, statin therapy had no significant effect on total sleep duration (WMD: –7.75 min, 95% CI: –18.98, 3.48, p = 0.176), sleep efficiency (WMD: 0.09%, 95% CI: –2.27, 2.46, p = 0.940), entries to stage I (WMD: 0.36, 95% CI: –0.91, 1.63, p = 0.580), or latency to stage I (WMD: –1.92 min, 95% CI: –4.74, 0.89, p = 0.181). In contrast, statin therapy significantly reduced wake time (WMD: –4.43 min, 95% CI: –7.77, –0.88, p = 0.014) and number of awakenings (WMD: –0.40, 95% CI: –0.46, –0.33, p < 0.001). Meta-regression did not suggest any correlation between changes in wake time and awakening episodes with duration of treatment and LDL-lowering effect of statins.

Conclusions

The results indicated that statins have no significant adverse effect on sleep duration and efficiency, entry to stage I, or latency to stage I sleep, but significantly reduce wake time and number of awakenings.  相似文献   
95.

Introduction

Correct restoration of the joint line is generally considered as crucial when performing total knee arthroplasty (TKA). During revision knee arthroplasty however, elevation of the joint line occurs frequently. The general belief is that this negatively affects the clinical outcome, but the reasons are still not well understood.

Material and methods

In this cadaveric in vitro study the biomechanical consequences of joint line elevation were investigated using a previously validated cadaver model simulating active deep knee squats and passive flexion-extension cycles. Knee specimens were sequentially tested after total knee arthroplasty with joint line restoration and after 4 mm joint line elevation.

Results

The tibia rotated internally with increasing knee flexion during both passive and squatting motion (range: 17° and 7° respectively). Joint line elevation of 4 mm did not make a statistically significant difference. During passive motion, the tibia tended to become slightly more adducted with increasing knee flexion (range: 2°), while it went into slighlty less adduction during squatting (range: –2°). Neither of both trends was influenced by joint line elevation. Also anteroposterior translation of the femoral condyle centres was not affected by joint line elevation, although there was a tendency for a small posterior shift (of about 3 mm) during squatting after joint line elevation. In terms of kinetics, ligaments lengths and length changes, tibiofemoral contact pressures and quadriceps forces all showed the same patterns before and joint line elevation. No statistically significant changes could be detected.

Conclusions

Our study suggests that joint line elevation by 4 mm in revision total knee arthroplasty does not cause significant kinematic and kinetic differences during passive flexion/extension movement and squatting in the tibio-femoral joint, nor does it affect the elongation patterns of collateral ligaments. Therefore, clinical problems after joint line elevation are probably situated in the patello-femoral joint or caused by joint line elevation of more than 4 mm.  相似文献   
96.
[Purpose] The objective of this study was to evaluate the usefulness of pedometry and accelerometry in the measurement of the energy expenditures in Nordic walking and conventional walking as diagnostic parameters. [Subjects and Methods] The study included 20 female students (age, 24 ± 2.3 years). The study used three types of measuring devices, namely a heart rate monitor (Polar S610i), a Caltrac accelerometer, and a pedometer (Yamax SW-800). The walking pace at the level of 110 steps/min was determined by using a metronome. [Results] The students who walked with poles covered a distance of 1,000 m at a speed 36.3 sec faster and with 65.5 fewer steps than in conventional walking. Correlation analysis revealed a moderate interrelationship between the results obtained with a pedometer and those obtained with an accelerometer during Nordic walking (r = 0.55) and a high correlation during conventional walking (r = 0.85). [Conclusion] A pedometer and Caltrac accelerometer should not be used as alternative measurement instruments in the comparison of energy expenditure in Nordic walking.Key words: Nordic walking, Accelerometer, Energy expenditure  相似文献   
97.
Infections that are triggered by the accompanying immunosuppression in patients with burn wounds are very common regardless of age. Among burn patients, the most frequently diagnosed infections include the bacterial ones primarily caused by Pseudomonas aeruginosa or Klebsiella pneumonia, as well as fungal infections with the etiology of Candida spp. or Aspergillus spp. Besides, burn wounds are highly susceptible to viral infections mainly due to the impaired immune responses and defective functions of the immune cells within the wound microenvironment. The most prevalent viruses that invade burn wounds include herpes simplex virus (HSV), cytomegalovirus (CMV), human papilloma virus (HPV), and varicella zoster virus (VZV). Likewise, less prevalent infections such as those caused by the orf virus or Epstein–Barr Virus (EBV) might also occur in immunosuppressed burn patients. Viral infections result in increased morbidity and mortality rates in severely burned patients. Additionally, a positive correlation between the hospitalization duration and the severity of the viral infection has been demonstrated. Viral infections trigger the occurrence of various complications, ranging from mild symptoms to even fatal incidents. Accurate detection of viral infection is of great clinical importance because of the possibility for a quicker introduction of proper treatment therapy and shortening of hospitalization time. The aim of this paper is to provide a comprehensive review of the literature and summarize the findings regarding the most common viral infections in immunosuppressed burn patients.  相似文献   
98.
The aim of the study was to determine the prevalence of Echinococcus multilocularis in red foxes (Vulpes vulpes) in Poland. Overall, 1,546 intestinal samples from 15 of the 16 provinces in Poland were examined by the sedimentation and counting technique (SCT). The mean prevalence of E. multilocularis in Poland was 16.5 % and was found in 14 of the 15 examined provinces. The mean intensity of infection was 2,807 tapeworms per intestine. Distinct differences in prevalence were observed between regions. In some provinces of eastern and southern Poland, the level of prevalence was 50.0 % (Warmińsko-Mazurskie), 47.2 % (Podkarpackie), 30.4 % (Podlaskie) and 28.6 % (Ma?opolskie), while in other provinces (west and south-west), only a few percent was found: 2.0 % (Dolno?l?skie), 2.5 % (Wielkopolskie) and 0.0 % (in Opolskie). The border between areas with higher and lower prevalence seems to coincide with a north–south line running through the middle of Poland, with prevalence from 17.5 to 50.0 % in the eastern half and from 0.0 to 11.8 % in the western half. The dynamic situation observed in the prevalence of this tapeworm indicated the necessity of continuing to monitor the situation concerning E. multilocularis in red foxes in Poland.  相似文献   
99.
Whether the fraction of total forest biomass distributed in roots, stems, or leaves varies systematically across geographic gradients remains unknown despite its importance for understanding forest ecology and modeling global carbon cycles. It has been hypothesized that plants should maintain proportionally more biomass in the organ that acquires the most limiting resource. Accordingly, we hypothesize greater biomass distribution in roots and less in stems and foliage in increasingly arid climates and in colder environments at high latitudes. Such a strategy would increase uptake of soil water in dry conditions and of soil nutrients in cold soils, where they are at low supply and are less mobile. We use a large global biomass dataset (>6,200 forests from 61 countries, across a 40 °C gradient in mean annual temperature) to address these questions. Climate metrics involving temperature were better predictors of biomass partitioning than those involving moisture availability, because, surprisingly, fractional distribution of biomass to roots or foliage was unrelated to aridity. In contrast, in increasingly cold climates, the proportion of total forest biomass in roots was greater and in foliage was smaller for both angiosperm and gymnosperm forests. These findings support hypotheses about adaptive strategies of forest trees to temperature and provide biogeographically explicit relationships to improve ecosystem and earth system models. They also will allow, for the first time to our knowledge, representations of root carbon pools that consider biogeographic differences, which are useful for quantifying whole-ecosystem carbon stocks and cycles and for assessing the impact of climate change on forest carbon dynamics.After acquisition via photosynthesis (gross primary production), new plant carbon (C) is respired, transferred to mycorrhizal symbionts, exuded, or converted into new biomass (net primary production). The new biomass can be foliage, stems (including boles, branches, and bark), roots, or reproductive parts. The proportional allocation of new C to these four plant biomass pools, when combined with their turnover rates, results in the proportional distribution of standing biomass among these pools. Such processes can be influenced by plant size, resource supply, and/or climate (110). Although simple in concept, our understanding of these processes and our ability to quantify and predict them remain surprisingly rudimentary (313).The general lack of knowledge about C partitioning is important for a number of reasons, including its implications for the accuracy of global C cycle modeling and accounting. A recent study (11) concluded
different carbon partitioning schemes resulted in large variations in estimates of global woody carbon flux and storage, indicating that stand-level controls on carbon partitioning are not yet accurately represented in ecosystem models.
Uncertainty about C partitioning in relation to biogeography and environmental effects is a particularly critical knowledge gap, because the direct and indirect influence of temperature or moisture availability on biomass partitioning could be important to growth, nutrient cycling, productivity, ecosystem fluxes, and other key plant and ecosystem processes (5, 710, 12). Additionally, uncertainty about belowground C allocation and biomass dynamics represents a major information gap that hampers efforts to estimate belowground C pools at continental to global scales (cf. 13 and 14).Some of the limited evidence available supports the hypothesis that under low temperatures both selection and phenotypic plasticity should promote a relatively greater fraction of forest biomass in roots (5, 7, 8, 12, 1518), as a result of adaptation to low nutrient supply (7, 1922) driven by low nutrient cycling rates and limited soil solution movement. Cold environments also are often periodically dry and exhibit low plant production (1926). Belowground resource limitations obviously also rise with increasing shortage of rainfall relative to evaporative demand, which can influence biomass distribution as well (4, 5, 17). Uncertainties include whether there are differences across climate gradients in the fraction of gross primary production respired vs. converted into new biomass; how new biomass is partitioned to foliage, stems, and roots; what the turnover rates are for these different tissues; and what are the consequences of the biomass distribution in foliage, stem, and root. In this study we focus on the last uncertainty—biomass distributions in standing pools—which is a direct consequence of new biomass allocation and subsequent turnover rate. Following optimal partitioning theory (14), we posit that the fraction of total forest biomass in roots should increase and in foliage should decrease when belowground resources are scarce.We use a large dataset based on more than 6,200 observations of forest stands in 61 countries (Tables S1–S3 and Fig. 1) to test the following hypotheses: (i) with increasing temperature, proportional biomass distribution (i.e., fraction of total biomass) should decrease in roots and increase in foliage; (ii) with increasing water shortage (estimated by an index of rainfall to evaporative demand), proportional biomass distribution should increase in roots and decrease in foliage; and (iii) gymnosperm and angiosperm forests should follow similar patterns. The dataset comprises data entries for individual stands including total foliage mass per hectare (Mfol), total stem mass per hectare (Mstem), total root mass per hectare (Mroot), and, where available, total mass per hectare (Mtot = Mfol + Mstem + Mroot). Forests were either naturally regenerated or plantations. Stands were classified as gymnosperm or angiosperm based on whichever represented a greater fraction of basal area or biomass; almost all native forests were of mixed species.Open in a separate windowFig. 1.Map showing location of all stands in the assembled database (see Tables S1 and S2 for additional information specific to those with root, foliage, and stem biomass data or with foliage and stem biomass data) across color-coded ranges of MAT.The sampled forests varied widely in age (from 3–400 y) and size (with Mtot ranging from near zero to 300 Mg/ha). Differences in biomass (which we refer to as size) reflect differences in productivity, density, and especially the range of ages of sampled stands. Because tree-size scaling is allometric (3, 4, 7, 9), we use an allometric approach to account for size-related changes in biomass partitioning in examining broad biogeographic patterns. Forests with high biomass have larger trees on average than forests with low biomass (given that tree density typically is lower in the former), so the forest size allometry characterized herein likely has its roots at the individual tree scale, but our analyses use stand Mtot, not individual tree biomass. We also examine biogeographic differences in the fraction of Mtot in foliage (Ffol), stem (Fstem), and root (Froot).The term “allocation” has been used historically to describe both the onward distribution, or flux, of newly acquired substances (usually C or biomass) to different plant functions and differences in how those pools are distributed at any point in time. To minimize confusion about these different measures. we hereafter use the term “allocation” along with “new biomass” or “new C” only to indicate the former and discuss either the proportion of biomass or the fraction of biomass distributed in foliage, stems, or roots to indicate the latter.The sampled forests varied widely geographically and in mean annual temperature (MAT) (from −13 to 29 °C) and mean annual precipitation (MAP) (from 20–420 cm) (Tables S1 and S2 and Fig. 1). Because a number of seasonal and annual climatic factors covary, it is difficult to ascertain which are responsible for the observed patterns (Materials and Methods and SI Materials and Methods). Because MAP is strongly correlated with MAT and is not a good global measure of water availability, we used an aridity index, the ratio of MAP to annual potential evapotranspiration (MAP/PET) (27) as a measure of relative water availability. MAP/PET ranged from <0.5 in cold, high-latitude zones to >3 in temperate and tropical rainforests. The forests ranged from sea level to >4,000 m elevation, with the large majority at <1,000 m elevation. More sampled forests were from Asia and Europe than other continents, and more were boreal and temperate than tropical. Thus, inferences from these data are likely to be most reliable across the gradient from subtropical to cold boreal forests.  相似文献   
100.
Polychlorinated biphenyls (PCBs) are toxic environmental pollutants. Humans are exposed to PCB mixtures via contaminated food or water. PCB exposure causes adverse effects in adults and after exposure in utero. PCB toxicity depends on the congener mixture and CYP1A2 gene activity. For coplanar PCBs, toxicity depends on ligand affinity for the aryl hydrocarbon receptor (AHR). Previously, we found that perinatal exposure of mice to a three‐coplanar/five‐noncoplanar PCB mixture induced deficits in novel object recognition and trial failures in the Morris water maze in Cyp1a2?/?::Ahrb1 C57BL6/J mice compared with wild‐type mice (Ahrb1 = high AHR affinity). Here we exposed gravid Cyp1a2?/?::Ahrb1 mice to a PCB mixture on embryonic day 10.5 by gavage and examined the F1 and F3 offspring (not F2). PCB‐exposed F1 mice exhibited increased open‐field central time, reduced acoustic startle, greater conditioned contextual freezing and reduced CA1 hippocampal long‐term potentiation with no change in spatial learning or memory. F1 mice also had inhibited growth, decreased heart rate and cardiac output, and impaired fertility. F3 mice showed few effects. Gene expression changes were primarily in F1 PCB males compared with wild‐type males. There were minimal RNA and DNA methylation changes in the hippocampus from F1 to F3 with no clear relevance to the functional effects. F0 PCB exposure during a period of rapid DNA de‐/remethylation in a susceptible genotype produced clear F1 effects with little evidence of transgenerational effects in the F3 generation. While PCBs show clear developmental neurotoxicity, their effects do not persist across generations for effects assessed herein.  相似文献   
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