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1.
Three experiments were conducted in hens to determine the effects of high levels of dietary phosphorus (P, 1-1.5%), chloride (Cl, 0.8%) or both on acid-base balance and eggshell quality and to consider whether any adverse effects on eggshell quality can be attributed to alteration of blood acid-base balance. Eggshell quality and values for a blood indicator of acid-base balance were reduced by high levels of dietary P or Cl in all of the experiments. Eggshell quality and values for the blood acid-base indicator were further reduced by high dietary levels of the combination of minerals. The adverse effects associated with high levels of the combination were greater than the sum of adverse effects associated with high levels of each mineral. The effects of P and Cl on plasma levels of these minerals were inconsistent and varied among experiments. The use of pair-fed controls revealed that the adverse effects of combined P and Cl on eggshell quality and acid-base balance were independent of their effects on feed and calcium intake. Calcium excretion was increased by consumption of the high P, high Cl diet. The information obtained from these experiments suggests that the adverse effects of high levels of dietary P and/or Cl on eggshell quality may be due, at least in part, to increased Ca excretion. This, in turn, may be mediated by acidemia resulting from the dietary manipulations, although the present data were insufficient to provide a direct link between acidemia and Ca excretion.  相似文献   
2.
Summary: Lymphatic filarial infection, from an immunologic point of view, is one of the most complex parasite infections. Not only are there different clinical manifestations that reflect differing immune responses, but the parasite's multiple stages, each with distinct anatomic tropism, add a compartmental layer of complexity to an already complicated process. Moreover, these parasites have finely tuned immune evasion strategies that enable escape from the innate immune system. As different stages of the parasite interact with different types of antigen‐presenting cells that, in turn, may play a significant role in shaping the subsequent adaptive immune response, the focus of this review is to provide insight into the interaction between filarial parasites and antigen‐presenting cells with an eye toward understanding how they influence parasite antigen‐driven T‐cell responses.  相似文献   
3.
Plasmonic metamaterials are artificial materials typically composed of noble metals in which the features of photonics and electronics are linked by coupling photons to conduction electrons of metal (known as surface _lasmon). These rationally designed structures have spurred interest noticeably since they demonstrate some fascinating properties which are unattainable with naturally occurring materials. Complete absorption of light is one of the recent exotic properties of plasmonic metamaterials which has broadened its application area considerably. This is realized by designing a medium whose impedance matches that of free space while being opaque. If such a medium is filled with some lossy medium, the resulting structure can absorb light totally in a sharp or broad frequency range. Although several types of metamaterials perfect absorber have been demonstrated so far, in the current paper we overview (and focus on) perfect absorbers based on nanocomposites where the total thickness is a few tens of nanometer and the absorption band is broad, tunable and insensitive to the angle of incidence. The nanocomposites consist of metal nanoparticles embedded in a dielectric matrix with a high filling factor close to the percolation threshold. The filling factor can be tailored by the vapor phase co-deposition of the metallic and dielectric components. In addition, novel wet chemical approaches are discussed which are bio-inspired or involve synthesis within levitating Leidenfrost drops, for instance. Moreover, theoretical considerations, optical properties, and potential application of perfect absorbers will be presented.  相似文献   
4.
Vection is the illusion of self-motion in the absence of real physical movement. The aim of the present study was to analyze how multisensory inputs (visual and auditory) contribute to the perception of vection. Participants were seated in a stationary position in front of a large, curved projection display and were exposed to a virtual scene that constantly rotated around the yaw-axis, simulating a 360° rotation. The virtual scene contained either only visual, only auditory, or a combination of visual and auditory cues. Additionally, simulated rotation speed (90°/s vs. 60°/s) and the number of sound sources (1 vs. 3) were varied for all three stimulus conditions. All participants were exposed to every condition in a randomized order. Data specific to vection latency, vection strength, the severity of motion sickness (MS), and postural steadiness were collected. Results revealed reduced vection onset latencies and increased vection strength when auditory cues were added to the visual stimuli, whereas MS and postural steadiness were not affected by the presence of auditory cues. Half of the participants reported experiencing auditorily induced vection, although the sensation was rather weak and less robust than visually induced vection. Results demonstrate that the combination of visual and auditory cues can enhance the sensation of vection.  相似文献   
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Objective

Emergency department (ED) patients with psychiatric chief complaints undergo medical screening to rule out underlying or comorbid medical illnesses prior to transfer to a psychiatric facility. This systematic review attempts to determine the clinical utility of protocolized laboratory screening for the streamlined medical clearance of ED psychiatric patients by determining the clinical significance of individual laboratory results.

Methods

We searched PubMed, Embase, and Scopus using the search terms “emergency department, psychiatry, diagnostic tests, laboratories, studies, testing, screening, and clearance” up to June 2017 for studies on adult psychiatric patients. This systematic review follows the recommendations of Meta‐analysis of Observational Studies in Epidemiology (MOOSE) statement. The quality of each study was rated according to the Newcastle‐Ottawa quality assessment scale.

Results

Four independent reviewers identified 2,847 publications. We extracted data from three studies (n = 629 patients). Included studies defined an abnormal test result as any laboratory result that falls out of the normal range. A laboratory test result was deemed as “clinically significant” only when patient disposition or treatment plan was changed because of that test result. Across the three studies the prevalence of clinically significant results were low (0.0%–0.4%).

Conclusions

The prevalence of clinically significant laboratory test results were low, suggesting that according to the available literature, routine laboratory testing does not significantly change patient disposition. Due to the paucity of available research on this subject, we could not determine the clinical utility of protocolized laboratory screening tests for medical clearance of psychiatric patients in the ED. Future research on the utility of routine laboratory testing is important in a move toward shared decision making and patient‐centered health care.
  相似文献   
7.
Methimazole is the most widely prescribed antithyroid medication in humans. However, hepatotoxicity is a deleterious adverse effect associated with methimazole administration. No specific protective agent has been developed against this complication yet. This study was designed to investigate the role of taurine as a hepatoprotective agent against methimazole-induced liver injury in mice. Different reactive metabolites were proposed to be responsible for methimazole hepatotoxicity. Hence, methimazole-induced liver injury was investigated in intact and/or enzyme-induced animals in the current investigation. Animals were treated with methimazole (200 mg/kg, by gavage), and hepatic injury induced by this drug was investigated in intact and/or enzyme-induced groups. Markers such as lipid peroxidation, hepatic glutathione content, alanine aminotransferase (ALT) and alkaline phosphatase (ALP) in plasma, and histopathological changes in the liver of animals were monitored after drug administration. Methimazole caused liver injury as revealed by increased plasma ALT. Furthermore, a significant amount of lipid peroxidation was detected in the drug-treated animals, and hepatic glutathione reservoirs were depleted. Methimazole-induced hepatotoxicity was more severe in enzyme-induced mice. The above-mentioned alterations in hepatotoxicity markers were endorsed by significant histopathological changes in the liver. Taurine administration (1 g/kg, i.p.) effectively alleviated methimazole-induced liver injury in both intact and/or enzyme-induced animals.  相似文献   
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9.
PurposeRenal Resistive Index (RRI) is a newly introduced sonographic index in predicting contrast-induced nephropathy (CIN) development. It has been suggested that RRI > 0.69 should be considered as a risk factor for CIN development. The present study aimed to calculate the predictive value of RRI using a cutoff point of 0.69.MethodsA total of 90 patients who were a candidate for coronary vessels angiography were enrolled in this study. Color Doppler ultrasonography was performed and RRI was measured. Patients were followed up for 48 hours after contrast media exposure for the CIN development. The diagnosis of CIN was based on a 25% relative rise or 0.5 mg/dL absolute rise in creatinine level. The predictive values of RRI were measured using 0.69 as a cutoff point.ResultsOut of 90 patients, CIN developed in 3 patients and 17 patients had preprocedural RRI > 0.69. Of 3 patients with CIN, 1 had RRI > 0.69. Using 0.69 as the cutoff point, the measured sensitivity and specificity of RRI were 33.3% and 83.9%, respectively.ConclusionsRRI > 0.69 is not a sensitive index in predicting the CIN development and cannot be used as an independent factor.  相似文献   
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