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891.
Aim: To analyze the autonomic control of heart rate variability (HRV) in subjects with peripheral hypothroidism undergoing hormone replacement therapy with L-thyroxine (L-T4) for 5-10 years. Methods: Thyroid profile, lipid profile, lipid-risk factors, parameters of oxidative stress [malondialdehyde (MDA)], inflammation [high-sensitive C-reactive protein (CRP)] and Heart rate variability (HRV) was analyzed in thirty-eight hypothyroid patients on treatment for more than five years and compared with healthy euthyroid volunteers of similar age, gender, and body composition. The link of oxidative stress with HRV parameters was assessed by Spearman-Rho correlation and regression analyses. Results: Hypothyroid patients on L-T4 treatment, had higher TSH (p<0.01), lipid profile (p<0.05) and lipid risk factors (p<0.05), high-sensitive C-reactive-protein (hsCRP) (3.31 versus 4.95 mg/L; p<0.05) and MDA (2.66 versus 6.87 mm/L; p <0.001) in serum. There was gross reduction in HRV parameters [reduced standard deviation of NN interval (SDNN), root mean square of successive differences between normal heartbeats (RMSSD), total power (TP) and elevated ratio of low to high frequency power (LF/HF ratio)] in patients. Elevated MDA was correlated with vagal withdrawal (decreased SDNN, RMSSD and TP) and TSH. In multiple regression analysis TSH and TP contributed to the rise in MDA. Conclusion: Hormone replacement therapy with L-T4 for hypothyroidism alone does not resolve persistent hyperlipidemia, oxidative stress and inflammation in primary hypothyroid patients even after five years of treatment. Association of oxidative stress with reduced cardiovagal modulation in these patients suggests persistence of cardiovascular risk despite standard treatment which warrants further investigation. 相似文献
892.
Sanjeeb K Sahoo Jayanth Panyam Swayam Prabha Vinod Labhasetwar 《Journal of controlled release》2002,82(1):105-114
Polyvinyl alcohol (PVA) is the most commonly used emulsifier in the formulation of poly lactide and poly (D,L-lactide-co-glycolide) (PLGA) polymeric nanoparticles. A fraction of PVA remains associated with the nanoparticles despite repeated washing because PVA forms an interconnected network with the polymer at the interface. The objective of this study was to determine the parameters that influence the amount of residual PVA associated with PLGA nanoparticles and its effect on the physical properties and cellular uptake of nanoparticles. Nanoparticles were formulated by a multiple emulsion-solvent evaporation technique using bovine serum albumin (BSA) as a model protein. The parameters that affected the amount of residual PVA include the concentration of PVA and the type of organic solvent used in the emulsion. The residual PVA, in turn, influenced different pharmaceutical properties of nanoparticles such as particle size, zeta potential, polydispersity index, surface hydrophobicity, protein loading and also slightly influenced the in vitro release of the encapsulated protein. Importantly, nanoparticles with higher amount of residual PVA had relatively lower cellular uptake despite their smaller particle size. It is proposed that the lower intracellular uptake of nanoparticles with higher amount of residual PVA could be related to the higher hydrophilicity of the nanoparticle surface. In conclusion, the residual PVA associated with nanoparticles is an important formulation parameter that can be used to modulate the pharmaceutical properties of PLGA nanoparticles. 相似文献
893.
There is much interest in utilizing the intrinsic properties of magnetic nanoparticles (MNPs) for the theranostic approaches in medicine. With an aim to develop a potential therapeutics for glioma treatment, efficacy of aqueous dispersible paclitaxel loaded MNPs (Pac-MNPs) were studied in glioblastoma cell line (U-87). The identified potential receptor, glycoprotein non-metastatic melanoma protein B (GPNMB) overexpressed by glioblastoma cells, was actively targeted using GPNMB conjugated Pac-MNPs in U-87 cells. As blood brain barrier (BBB) is the primary impediment in the treatment of glioblastoma, therefore, an attempt was taken to evaluate the biodistribution and brain uptake of Pac-MNPs in rats. The bioavailability of Pac-MNPs illustrated a prolonged blood circulation in vivo, which demonstrated the presence of significant amounts of drug in rat brain tissues as compared to native paclitaxel. Further, the transmission electron microscopy (TEM) study revealed significant accumulation of the Pac-MNPs in the brain tissues. Being an effective contrast enhancement agent for magnetic resonance imaging (MRI) at tissue levels, the MNPs devoid of any surfactant demonstrated enhanced contrast effect in liver and brain imaging. Hence, the significant prevalence of drugs in the rat brain tissues, in vitro targeting potentiality as well as the augmented contrast effect elicit the non-invasive assessment and theranostic applications of MNPs for brain tumor therapy. 相似文献
894.
895.
Deepali Singhal Ashok Nanda Sanghamitra Kanungo Kalyani Sahoo Santosh Mohapatra 《Indian journal of ophthalmology》2022,70(2):425
Purpose:To compare the efficacy of topical nonsteroidal anti-inflammatory drugs (NSAIDs) and prednisolone acetate in controlling inflammation and preventing cystoid macular edema (CME) after uneventful phacoemulsification.Methods:All patients who underwent uneventful phacoemulsification from December 2020 to Feb 2021 were included in the study. These were randomly assigned to receive any one anti-inflammatory agent among topical nepafenac (0.1%) [96 eyes], bromfenac (0.07%) [93 eyes], preservative-free ketorolac (0.4%) [94 eyes], nepafenac (0.3%) [96 eyes], or prednisolone acetate (1%) [91 eyes]. The efficacy of the drugs was evaluated by comparing the grade of anterior chamber (AC) cells, conjunctival hyperemia, pain score, visual acuity, intraocular pressure (IOP), and central macular thickness (CMT) at 1 and 6 weeks after surgery.Results:At 1 and 6 weeks, there was no significant difference in pain score, conjunctival hyperemia, AC cells, change in IOP, and visual acuity between the prednisolone and the NSAIDs groups, though nepafenac 0.3% was most effective. At 6 weeks, there was no significant difference in the number of patients developing subclinical CME in the prednisolone versus NSAID group. The mean increase in CMT was significantly lower in nepafenac 0.3% than prednisolone at 1 and 6 weeks (P = 0.003 and 0.004, respectively).Conclusion:NSAIDs used in isolation are comparable to prednisolone in preventing inflammation and pain after uneventful phacoemulsification. However, nepafenac 0.3% is most comparable to prednisolone and more efficacious in reducing the incidence of CME. We recommend that nepafenac 0.3% can be used as a sole anti-inflammatory agent in patients with uneventful phacoemulsification. 相似文献
896.
Triad of columnar cell alteration, lobular carcinoma in situ, and tubular carcinoma of the breast 总被引:1,自引:0,他引:1
Columnar cell alteration in the breast encompasses a spectrum of pathologic changes ranging from simple columnar cell change to more complex columnar cell hyperplasia with and without atypia to in situ carcinoma, often with a micropapillary architecture. For reasons that remain unclear, the columnar cell lesions are associated with tubular carcinomas and lobular carcinoma in situ. Therefore it is important to be familiar with the spectrum of changes and the associated lesions, especially in breast core biopsies for further management. 相似文献
897.
John R. Zullo Rajat J. Kudchadker X. Ronald Zhu Narayan Sahoo Michael T. Gillin 《Medical Dosimetry》2010,35(1):63-66
In the region of high-dose gradients at the end of the proton range, the stopping power ratio of the protons undergoes significant changes, allowing for a broad spectrum of proton energies to be deposited within a relatively small volume. Because of the potential linear energy transfer dependence of LiF TLD-100 (thermolumescent dosimeter), dose measurements made in the distal fall-off region of a proton beam may be less accurate than those made in regions of low-dose gradients. The purpose of this study is to determine the accuracy and precision of dose measured using TLD-100 for a pristine Bragg peak, particularly in the distal fall-off region. All measurements were made along the central axis of an unmodulated 200-MeV proton beam from a Probeat passive beam-scattering proton accelerator (Hitachi, Ltd., Tokyo, Japan) at varying depths along the Bragg peak. Measurements were made using TLD-100 powder flat packs, placed in a virtual water slab phantom. The measurements were repeated using a parallel plate ionization chamber. The dose measurements using TLD-100 in a proton beam were accurate to within ±5.0% of the expected dose, previously seen in our past photon and electron measurements. The ionization chamber and the TLD relative dose measurements agreed well with each other. Absolute dose measurements using TLD agreed with ionization chamber measurements to within ± 3.0 cGy, for an exposure of 100 cGy. In our study, the differences in the dose measured by the ionization chamber and those measured by TLD-100 were minimal, indicating that the accuracy and precision of measurements made in the distal fall-off region of a pristine Bragg peak is within the expected range. Thus, the rapid change in stopping power ratios at the end of the range should not affect such measurements, and TLD-100 may be used with confidence as an in vivo dosimeter for proton beam therapy. 相似文献
898.
899.
Neurofibromatosis type 1 (NF1), affecting primarily the growth of neural crest-derived tissues, is one of the most common autosomal dominant genetic disorders with an unusually high spontaneous mutation rate. In four cases of sporadic NF1, demonstrated by hemizygosity to have a deletion involving the NF1 gene, we were able to assign the deletion event to the maternally derived chromosome. One of these individuals was determined to be a somatic mosaic for NF1, as a trace of the maternally derived haplotype was detected at the NF1 locus. This indicated a postzygotic, as opposed to gametic, deletion event. It may be that somatic mosaicism is more common in NF1 than has hitherto been appreciated and may responsible in part for the high mutation rate in this disorder. In addition, it is suggested that the mechanism(s) of gene deletion is subject to a parent of origin effect, being more frequent on the maternally derived chromosome. This is in contrast to the other types of mutations which, in sporadic NF1, have been found to occur preferentially on the paternally derived chromosome. Hum Mutat 9:452–457, 1997 © 1997 Wiley-Liss, Inc. 相似文献
900.
D. Sahoo P. Priyadarshini R. Dandela D. Alagarasan R. Ganesan S. Varadharajaperumal R. Naik 《RSC advances》2021,11(26):16015
The photosensitivity of amorphous chalcogenide thin films brings out light-induced changes in the nonlinear and linear optical parameters upon sub-bandgap and bandgap laser irradiation. The present work reports the in situ laser irradiated changes in the optical properties of As50Se40Sb10 thin films. The thermally evaporated film showed an exponential decrease in optical bandgap and increase in Urbach energy. The decay rate of the bandgap was 6.24 min and growth rate of Urbach energy was 6.67 min respectively. The dynamics of photo-induced changes were observed from the changes in linear refractive index and its dependent parameters such as 3rd order nonlinear susceptibility, nonlinear refractive index, dispersion and dielectric parameters. The conversion of heteropolar to homopolar bonds induced the photodarkening mechanism that changed the dispersion parameters. The decrease in Ed and Eo reduced the oscillator strength along with the zero-frequency dielectric constant. The optical and electrical conductivity changed significantly with time. The changes were saturated with time which brings stability in the film properties that is useful for various optical applications. However, no structural and compositional changes upon laser irradiation were noticed from the X-ray diffraction and EDX studies respectively. The surface homogeneity was checked from the FESEM picture.The photosensitivity of amorphous chalcogenide thin films brings out light-induced changes in the nonlinear and linear optical parameters upon sub-bandgap and bandgap laser irradiation. 相似文献