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Objective  

To quantify myocardial iron stores by Cardiac Magnetic Resonance (CMR).  相似文献   
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Rapidly growing soft- tissue lesions in the oral and maxillofacial region can represent a variety of diagnoses involving radically different treatment modalities. Accurate diagnosis is important to avoid unnecessary and often mutilating surgery. Nodular fascitis is a rapidly proliferating fibroblastic lesion that presents as a tumour- like mass. Up to 20% of cases occur in the head and neck region.  相似文献   
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Introduction  The classic intact canal wall (ICW) mastoidectomy with tympanoplasty (combined approach tympanoplasty) [1, 2] has anatomic constraints for clearance of disease from the anterior attic and sinus tympani leading to high recidivism. Farrior [3, 4] described the modification of this technique and senior author (AM) has been using it with further modifications since 1973. Materials and methods  We report our long-term experience in hearing and healing in 126 cases with special reference to the age (pediatric versus adults), ossicle status (presence or absence of stapes suprastructure) and type of cholesteatoma (Attic versus posterior-superior versus secondary acquired cholesteatoma). Results  All the patients had unsafe CSOM and underwent Modified ICW mastoidectomy with primary ossiculoplasty except five where the procedure was staged. Conclusion  Modified ICW technique is a one-stage procedure with the lowest recidivism rate when compared to various other ICW techniques. There is no significant difference in relation to age of the patient or type of cholesteatoma if the operative cases are selected judicially.  相似文献   
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rDEN2/4Delta30(ME) is an attenuated chimeric dengue virus in which the prM and E structural proteins of the DEN4 candidate vaccine rDEN4Delta30 have been replaced by those of the prototypic DEN2 NGC virus. rDEN2/4Delta30(ME) was evaluated at a dose of 1,000 PFU in 20 healthy dengue-na?ve adult volunteers. Eight volunteers received placebo. Volunteers were monitored closely for adverse events and serum was collected for determination of the level and duration of viremia and neutralizing antibody response. The vaccine was well tolerated by all volunteers. The most common adverse events observed were a transient asymptomatic rash and mild neutropenia. All vaccines seroconverted to DEN2 and maintained significant antibody titers throughout the six-month trial duration. Eleven vaccinees had vaccine virus recovered from the blood during the study. RNA derived from virus isolates obtained from viremic volunteers was sequenced for confirmation of retention of the Delta30 mutation in the 3' UTR. The Delta30 mutation remained unchanged in each isolate, confirming the stability of the Delta30 mutation. Further evaluation of this vaccine in a tetravalent formulation is warranted.  相似文献   
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In this work, we found that bone mineral formation proceeded very rapidly in mice by 1 day of age, where the degree of mineralization, the tissue mineral density, and the mineral crystallinity reached 36%, 51%, and 87% of the adult values, respectively. However, even though significant mineralization had occurred, the elastic modulus of 1-day-old bone was only 14% of its adult value, indicating that the intrinsic stiffening of the bone lags considerably behind the initial mineral formation. INTRODUCTION: To meet the mechanical challenges during early development, the skeleton requires the rapid accretion of bone quality and bone quantity. Here, we describe early bone development in the mouse skeleton and test the hypothesis that specific compositional properties determine the stiffness of the tissue. MATERIALS AND METHODS: Tibias of female BALB mice were harvested at eight time-points (n = 4 each) distributed between 1 and 40 days of age and subjected to morphometric (muCT), chemical (Fourier transform infrared microspectroscopy), and mechanical (nanoindentation) analyses. Tibias of 450-day-old mice served as fully mineralized control specimens. RESULTS: Bone growth proceeded very rapidly; at 1 day of age, the degree of mineralization (phosphate/protein ratio), the density of mineralized bone (TMD), and mineral crystallinity had reached 36%, 51%, and 87% of the adult (450 days) values, respectively. Spatially, the variability in mineralization across the mid-diaphysis was very high for the early time-points and declined over time. In contrast to the notable changes in mineralization, carbonate substitution into the mineral lattice (carbonate/phosphate ratio) and collagen cross-linking did not show any significant changes over this time period. Even though significant mineralization had occurred, the elastic modulus of 1-day-old bone was only 14% of the adult value and increased to 89% (of its adult value) after 40 days. Between samples of different time-points, significant positive correlations were observed between the elastic modulus and TMD (r(2) = 0.84), phosphate/protein ratio (r(2) = 0.59), and crystallinity (r(2) = 0.23), whereas collagen cross-linking showed a small but significant negative correlation (r(2) = 0.15). CONCLUSIONS: These data indicate that specific chemical and morphometric properties modulate bone's stiffness during early growth. The intrinsic stiffening of the bone, however, lags considerably behind the initial mineral formation, emphasizing the importance of bone mineral quality for optimizing matrix integrity.  相似文献   
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During 1980 to 2004, 1602 Canal Wall Down (CWD) procedures was performed of which 978 had primary surgery and 624 were revision cases. We have highlighted various methods for total clearance of disease process from the tympanomastoid area, making of a smooth cavity, augmentation of middle ear space for better functional results, inlay temporalis fascia grafting, ossiculoplasty with live tissue grafts, natural obliteration of the cavity and meatoplasty. Healing of cavity and tympanic membrane (TM) graft was achieved in 1548 (94.2%) of cases. Revision surgery was performed in 32 cases for recurrence or residual cholesteatoma, mostly in the attic and middle ear. Persisting discharge was present in 12 cases. Serviceable hearing (airbone (A–B) gap closure up to 20 dB) was achieved in 1017 (63.5%) cases. Hearing was worse than pre-operative level in 154 (9.6%) cases. There was no improvement in hearing in 397 (24.8%) cases. Serviceable hearing was obtained after second stage ossiculoplasty in 34 (2%) cases.  相似文献   
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