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71.
72.
Borah BJ  Burns ME  Shah ND 《Health economics》2011,20(9):1025-1042
High deductible health plans (HDHPs) have become an increasingly common form of benefit design used by employers to manage health-care costs. Numerous studies have evaluated the uptake and impact of HDHPs on health-care utilization. Most studies have employed the standard difference-in-differences (DID) methodology. In this paper, we employ three alternative methodologies to evaluate a natural experiment in which a traditional health plan was fully replaced by a HDHP. We implement the standard DID and the quantile difference-in-differences (QDID) estimators to evaluate the impact of the HDHP on following six outcomes: overall cost, medical cost, pharmacy cost, outpatient visit count, inpatient visit count and emergency room visit count. We compare these results to a changes-in-changes (CIC) estimator, a generalized version of the standard (DID) estimator. We find that both the DID and CIC models yielded similar results, while the QDID model provided additional insights on the HDHP impact across different parts of the outcome distributions. Overall, introduction of HDHP had no impact on health-care costs, positive impact on the number of outpatient visits and mixed impacts on the inpatient and emergency room visit counts. The QDID estimates suggest HDHP introduction generally impacted subjects in upper percentiles (50th, 75th and 90th).  相似文献   
73.
74.
Multicolor labeling of biological samples with large volume is required for omic-level of study such as the construction of nervous system connectome. Among the various imaging method, two photon microscope has multiple advantages over traditional single photon microscope for higher resolution and could image large 3D volumes of tissue samples with superior imaging depth. However, the growing number of fluorophores for labeling underlines the urgent need for an ultrafast laser source with the capability of providing simultaneous plural excitation wavelengths for multiple fluorophores. Here, we propose and demonstrate a single-laser-based four-wavelength excitation source for two-photon fluorescence microscopy. Using a sub-100 fs 1,070-nm Yb:fiber laser to pump an ultrashort nonlinear photonic crystal fiber in the low negative dispersion region, we introduced efficient self-phase modulation and acquired a blue-shifted spectrum dual-peaked at 812 and 960 nm with 28.5% wavelength conversion efficiency. By compressing the blue-shift near-IR spectrum to 33 fs to ensure the temporal overlap of the 812 and 960 nm peaks, the so-called sum frequency effect created the third virtual excitation wavelength effectively at 886 nm. Combined with the 1,070 nm laser source as the fourth excitation wavelength, the all-fiber-format four-wavelength excitation source enabled simultaneous four-color two-photon imaging in Brainbow AAV-labeled (TagBFP, mTFP, EYFP, and mCherry) brain samples. With an increased number of excitation wavelengths and improved excitation efficiency than typical commercial femtosecond lasers, our compact four-wavelength excitation approach can provide a versatile, efficient, and easily accessible solution for multiple-color two-photon fluorescence imaging in the field of neuroscience, biomolecular probing, and clinical applications with at least four spectrally-distinct fluorophores.  相似文献   
75.
A simple and modified top-down approach to synthesize molybdenum oxide (MoOx: x = 2, 3) quantum dots (QDs) is proposed in this study. This modified approach involves the conversion of a bulk powder material into thin films followed by a sonication induced chemical etching process for synthesising QDs. X-Ray Diffraction (XRD) is used for crystal structural characterization of MoOx thin films. The crystal structure properties of the MoOx QDs are analysed by High Resolution Transmission Electron Microscopy (HRTEM) images and corresponding Selected Area Electron Diffraction (SAED) patterns. The optical band gap is estimated by Tauc''s plot from UV-Vis-NIR absorption spectra. The excitation dependent photoluminescence (PL) emission of MoOx QDs as a function of acid concentration is investigated. The growth mechanism of QDs in different crystalline phases as a function of acid concentration is also exemplified in this work. The micro-Raman and Fourier Transform of Infrared (FTIR) spectra are recorded to analyse the vibrational spectrum of the molybdenum–oxygen (Mo–O) bonds in the MoOx QDs.

A simple and modified top-down approach to synthesize molybdenum oxide (MoOx: x = 2, 3) quantum dots (QDs) is proposed in this study.  相似文献   
76.
Risedronate reduces the risk of vertebral fractures by up to 70% within the first year of treatment. Increases in bone mineral density or decreases in bone turnover markers explain only a portion of the anti-fracture effect, suggesting that other factors, such as changes in trabecular bone architecture, also play a role. Our objective was to determine the effects of risedronate on bone architecture by analyzing iliac crest bone biopsy specimens using three-dimensional microcomputed tomography (3-D µCT). Biopsy specimens were obtained at baseline and after 1 year of treatment from women enrolled in a double-blind, placebo-controlled study of risedronate 5 mg daily for the prevention of early postmenopausal bone loss. Trabecular architecture deteriorated in the placebo group (n = 12), as indicated by a 20.3% decrease in bone volume (25.1% vs. 20.0%, P = 0.034), a 13.5% decrease in trabecular number (1.649 vs. 1.426 mm–1, P = 0.052), a 13.1% increase in trabecular separation (605 vs. 684 µm, P = 0.056), and an 86.2% increase in marrow star volume (3.251 vs. 6.053 mm3, P = 0.040) compared with baseline values. These changes in architectural parameters occurred in the presence of a concomitant decrease from baseline in lumbar spine bone mineral density (–3.3%, P = 0.002), as measured by dual energy x-ray absorptiometry. There was no statistically significant (P < 0.05) deterioration in the risedronate-treated group (n = 14) over the 1-year treatment period. Comparing the actual changes between the two groups, the placebo group experienced decreases in bone volume (placebo, –5.1%; risedronate, +3.5%; P = 0.011), trabecular thickness (placebo, –20 µm; risedronate, +23 µm; P = 0.032), and trabecular number (placebo, –0.223 mm–1; risedronate, +0.099 mm–1; P = 0.010), and increases in percent plate (placebo, +2.79%; risedronate, –3.23%; P = 0.018), trabecular separation (placebo, +79 µm; risedronate, –46 µm; P = 0.010) and marrow star volume (placebo, +2.80 mm3 ; risedronate, –2.08mm3; P = 0.036), compared with the risedronate group. These data demonstrate that trabecular architecture deteriorated significantly in this cohort of early postmenopausal women, and that this deterioration was prevented by risedronate. Although there is no direct link in this study between fracture and preservation of architecture, it is reasonable to infer that the preservation of bone architecture may play a role in risedronates anti-fracture efficacy.  相似文献   
77.
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - The present investigation deals with the morphological, physical and spectroscopic characteristics of the...  相似文献   
78.
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - The study aimed at possible bioremediation of textile mill effluent (TE) and simultaneous production of...  相似文献   
79.
Tympanoplasty     
The study comprises of 164 ears of modified radical mastoidectomy with tympanoplasty performed as one stage operation in our hospital. The ears were followed up for 5 years. Out of these 164 ears, postaural approach was performed in 90 ears and endaural with removal of bone from inside out in 74 ears. Tympanoplasty was performed in all the cases as one stage operation with incus transposition in 42 cases, autogenous cortical bone columella between malleus handle and stapes head in 80 cases, between stapes footplate and graft material in 30 cases and preserved homograft ossicles between stapes footplate and graft in 12 cases. Dry ears with graft take up occurred in 92% cases within 6 to 10 weeks. No recurrence of cholesteatoma was seen. Ossiculoplasty using autogenous cortical bone columellas resulted in somewhat greater improvement in the post operative airbone gap than ossiculoplasty with auto or homograft ossicles. Similarly the post operative gap improved more with an intact stapes superstructure than in ears where the stapes superstructure was absent. The use of a cortical bone can be recommended in cases where the patient’s own ossicles are affected by disease and cannot be used.  相似文献   
80.
Short-latency somato sensory evoked potentials (SEPs) were recorded in 45 freshly diagnosed cases of epilepsy before starting treatment. Follow-up recordings were made 6 weeks and 3 months after diphenylhydantoin, carbamazipine and phenobarbitone monotherapy were started. Serum drug levels were monitored. Both amplitude and latency of the initial component (N20) remained unchanged and were identical to a group of 30 age- and sex-matched normal individuals in whom SEPs were recorded during the period of study.  相似文献   
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