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91.

Objective

This work aimed for using multislice computed tomography (MSCT) to map the bronchial tree and assess the exact site, direction, airway findings and bronchial measurements to guide trans-bronchial lung biopsy from an inaccessible lung lesion.

Patients and methods

This study was carried on 26 patients. It was conducted in the Radiology Department, in collaboration with Chest Department, in the period from January 2015 to April 2016. All patients were subjected to Virtual Bronchographic (VB) examination and Trans-Bronchial lung biopsy (in selected cases guided by the VB results).

Results

In this study, MSCT-VB maps guided the fiber-optic bronchoscopy in 30 bronchial lesions in 26 patients to the proper sampling site for different lung lesions with success rate 100% and CT maps were done, reaching 3rd to 7th order bronchial generation with mean distance from central bronchi was 21.3?mm and mean target bronchial diameter was 1.9?mm. Right sided lesions encountered in 57.7% and left sided lesions in 42.3% with the most common segmental affection was the right upper lobe in 36.7% of bronchial lesions and the apico-posterior subsegment of left upper lobe in 23.3% of lesions, then planning according to the site of the lesion in relation to the bronchial tree in the VB was done. Histopathological assessment was done with 61.5% neoplastic lesions and 38.5% inflammatory lesions.

Conclusion

Multiplanar reconstruction images together with virtual bronchographic images were accurate in the detection of lesion’s site, depiction of degree of narrowing, and distal visualization of airways. This CT map should be used to guide bronchoscopy or to direct trans-bronchial needle biopsy to guarantee positive histopathological results.  相似文献   
92.
Ras protein signaling pathways are important in controlling the plight of different types of cancer.Here we discussed the paper entitled "Small molecule stabilization of the KSR inactive state antagonizes oncogenic Ras signalling" published in Nature journal on inactivating the kinase suppressor of Ras (KSR) protein using a small molecule as an inhibitor by Dhawan et al.A biphenyl ether analogue of a quinazoline binds in one of the binding pockets of KSR and results in stabilization of its inactive state.In this inactive state,KSR is unable to take part in the cascade of protein association to perform the signalling process.  相似文献   
93.
There is a need for better understanding of the biocompatibility of alginate-polycation microcapsules based on their physicochemical characteristics. Microcapsules composed of alginate with 44% (IntG) or 71% (HiG) guluronate, gelled with calcium (Ca) or barium (Ba) and coated with poly-L-lysine (PLL) or poly-l-ornithine (PLO), followed by IntG alginate were compared. For microcapsules with an IntG(Ca) gel core, using PLO instead of PLL resulted in less immune cell adhesion after 2 days in C57BL/6J mice. The PLO microcapsules were also characterized by greater hydrophilicity and superior resistance to swelling and damage under osmotic stress. For microcapsules with a PLL membrane, replacing the IntG(Ca) gel core with IntG(Ba) or HiG(Ca) gel resulted in stronger immune responses (p<0.05). This was explained by poor penetration of PLL into the gel, as demonstrated by Fourier transform infrared spectroscopy analyses and membrane rupturing during osmotic swelling. X-ray photoelectron spectroscopy analyses show that all microcapsules had the same amount of polycation at their surface. Moreover, alginate coatings had non-significant effects on the biocompatibility and physicochemical properties of the microcapsules. Thus, alginate-polycation interactions for membrane formation are more important for biocompatibility than either the quantity of polycation at the surface or the alginate coating.  相似文献   
94.
95.
Arrode G  Hegde R  Jin Y  Singh DK  Narayan O  Chebloune Y 《Vaccine》2008,26(31):3795-3804
Gag-CD8+ T cell responses are associated with immune control of HIV infection. Since during HIV infection Nef impairs T cell responses, we evaluated whether deletion of nef from a non-infectious HIV DNA vaccine (Delta4 Nef+), creating Delta5 Nef(-), would affect its immunogenicity. When compared with Delta4, mice injected with Delta5 developed significantly lower CD8+ T cell responses to Gag, but no significant change in the responses to Env was observed. In vitro, deletion of Nef abrogated the induced cell death, production of virus-like particles and release of Gag from transfected cells. Thus, the effect of Nef in causing extrusion of Gag might adjuvant the CD8+ T cell responses to Gag in DNA vaccine.  相似文献   
96.
Dental implant screw fracture involves attempting to retrieve the screw fragment or, as an alternative, attempting to salvage the dental implant. Circumstances that do not allow for screw retrieval require a solution in which the internal configuration of the dental implant can provide for a custom direct dowel fabrication. The proposed technique is to retrofit the fabrication of a custom cast dowel-core and provisional use of a direct procedure, which provides accuracy of fit, retention, and ease of production.  相似文献   
97.
STATEMENT OF PROBLEM: Little is known about how craniofacial bones that are distant from dental implants are loaded. Whether bone experiences different strain when implants of different diameters are loaded is unknown. PURPOSE: This study was designed to (1) characterize bone strain both adjacent to and distant from dental implants and (2) compare bone strain in response to the same loads on small-diameter and large-diameter implants. MATERIAL AND METHODS: On 4 edentulous, dry adult human skulls, the buccopalatal midpoint of the edentulous occlusal surface was marked unilaterally in the maxillary first molar area with a round bur. A hole for implant placement was prepared, and 2 self-tapping titanium implants (3.75 x 7 mm and 4 x 7 mm) were placed in the same location and at the same orientation, one after the other. A 4-mm-long titanium abutment was connected to the implant. Each implant was loaded 10 degrees lateral to its longitudinal axis, simulating a lateral occlusal force in 3 of the skulls. In skull 2, loading was along the longitudinal axis of the implant and simulated a vertical occlusal force. The magnitude of the ramp forces was 0 to 100 N. Uniaxial strain gages and/or 3-element strain rosettes were implanted in the supramolar cortical bone, the supraincisor cortical bone, the zygomaticomaxillary suture, and the zygomaticotemporal suture. All strain gages/rosettes were excited with 500 mV DC, and the output signals were recorded with a strain conditioner. Tensile strain was expressed as positive values and compressive strain as negative values. Student t tests were used to test for normal distribution of bone strain within each skull; Wilcoxon tests were applied for skewed distribution between small- and large-diameter implants and between 50-N and 100-N loads (P相似文献   
98.

Introduction  

More than 200 mutations have been found in patients with Gaucher disease (GD) and some mutations usually have a high frequency in certain populations. Genotype/phenotype correlation in patients with GD has not been established. This study was designed to determine underlying mutations in Egyptian children with GD and to assess their relation to disease phenotypes.  相似文献   
99.
100.
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