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901.
902.
903.
JF Meneses-Echávez PA Alba-Ramírez JE Correa-Bautista 《Journal of cancer education》2018,33(6):1294-1300
This study aims to determine the effects of an educational intervention, based on the Colombian guidelines for educational communication in the framework of cancer control, for raising lung cancer prevention-related awareness, and improving healthy lifestyles in female scholars from a low-income area in Bogota, Colombia. Uncontrolled trial conducted in 243 female scholars (mean age 14 years ± 1.5 SD). Two 90 min educational sessions were carried out in March 2015 according to the Colombian guidelines for educational communication in the framework of cancer control. Posters and other educational materials were created by scholars after the intervention. All participants completed a self-reported questionnaire—The Cancer Awareness Measure—at pre and post-intervention, as well as 1, 3, and 6 months after the intervention. Smoking prevalence (8.2% at baseline) was reduced by 3.7% at 6 months follow-up (p < 0.005). The scholars exhibited low to moderate awareness of both warning signs and risk factors for lung cancer at baseline. These variables showed statistically significant improvements at 6 months follow-up (p < 0.005). Similar improvements were also found for physical activity, high-fat diet, and fruits and vegetable intake. This evaluation of the Colombian guidelines for educational communication in the framework of cancer control raised awareness towards lung cancer prevention, reduced smoking, and improved other healthy-lifestyle-related factors in a group of female scholars from a low-income area in Bogota, Colombia. Further randomized controlled studies are needed. 相似文献
904.
The practitioner placing dental implants has many options with respect to pre-implant radiographic assessment of the jaws. The advantages and disadvantages of the imaging modalities currently available for pre-implant imaging are discussed in some detail. Intra-oral and extra-oral radiographs are generally low dose but the information provided is limited as the images are not three-dimensional. Tomography is three-dimensional, but the image quality is highly variable. Computed tomography (CT) has been the gold standard for many years as the information provided is three-dimensional and generally very accurate. However, CT examinations are expensive and deliver a relatively high radiation dose to the patient. The latest imaging modality introduced is cone beam volumetric tomography (CBVT) and this technology is very promising with regard to pre-implant imaging. CBVT generally delivers a lower dose to the patient than CT and provides reasonably sharp images with three-dimensional information. A comparison between CT and CBVT is provided. Magnetic resonance imaging is showing some promise, but the examinations are not readily available, generally expensive and bone is not well imaged. Magnetic resonance imaging is excellent for demonstrating soft tissues and therefore may be of great use in identifying the inferior dental nerve and vessels. All of the above technology is of little value if the information required is not obtained and so information is also provided on imaging of some of the vital structures. Of particular interest is the inferior dental canal, incisive canals of the mandible, genial foramina and canals, maxillary sinus and the incisive canal and foramen of the maxilla. 相似文献
905.
P. Romagnoli N. Pimpinelli M. Mori PA Reichart LR Eversole G. Ficarra 《Oral diseases》1997,3(2):99-105
OBJECTIVE: The purpose of this study was to elucidate the pathogenesis of oral candidiasis, a common cause of discomfort and social impairment among HIV-infected individuals.
STUDY DESIGN, MATERIALS AND METHODS: The oral mucosal immune system cells were analysed by immunohistochemistry and electron microscopy in biopsies from five erythematous and four pseudomem-branous candidiasis cases and were compared with those from seven HIV-positive and 10 HIV-negative controls without candidiasis.
RESULTS: The superficial lamina propria and basal epithelial layer was populated by CD1a+ Langerhans cells with infiltration of CD8+ lymphocyteS. Within the submu-cosa are CD36+ dendritic macrophages and lymphocytes, although CD4+ subsets were absent from the infiltrate. The expression of human leukocyte antigen system, DR locus (HLA-DR) and leukocyte specific adhesion molecules was low in erythematous, yet more marked in pseudomembranous candidiasiS. In the pseudomembra-nous form, CD14+ leukocytes were found in the basal epithelial layer. Langerhans cells were significantly more numerous and were richer in dendrites and Birbeck granules in erythematous than in pseudomembranous can-didiasis.
CONCLUSIONS: Candidiasis is associated with alterations in the number and differentiation of lymphocytes and dendritic cells, being more severe in the pseudo-membranous than erythematous form. We propose that these alterations play a role in the pathogenesis and evolution of the disease. 相似文献
STUDY DESIGN, MATERIALS AND METHODS: The oral mucosal immune system cells were analysed by immunohistochemistry and electron microscopy in biopsies from five erythematous and four pseudomem-branous candidiasis cases and were compared with those from seven HIV-positive and 10 HIV-negative controls without candidiasis.
RESULTS: The superficial lamina propria and basal epithelial layer was populated by CD1a
CONCLUSIONS: Candidiasis is associated with alterations in the number and differentiation of lymphocytes and dendritic cells, being more severe in the pseudo-membranous than erythematous form. We propose that these alterations play a role in the pathogenesis and evolution of the disease. 相似文献
906.
OBJECTIVES: The aim of this study was to identify the principle clinical features of the peripheral giant cell granuloma (PGCG), and to recognise clinical features of PGCG that are poorly defined.
DESIGN: We reviewed retrospectivety 77 cases of PGCG from 62 patients, from our files with respect to incidence, sex, patient age, race, clinical symptoms and signs, radio-graphic features and recurrence following excision.
RESULTS AND CONCLUSIONS: Our results were largety in agreement with previous reports, although there is wide variation in the results published between series. In addition, some clinical features of PGCG are poorly defined. Little is known about the retative incidences of PGCG and central giant cell granuloma. An association between PGCG and tooth loss may exist, but is poorly defined, and not all PGCG that involve edentulous areas follow recent tooth loss. Information about PGCG recurrence after excision is limited, and does not necessarily follow incomplete excision. Despite the large number of reported cases of PGCG, clarification of some clinical features is required, and may hetp formulation and interpretation of future laboratory-based research into this poorly understood lesion. 相似文献
DESIGN: We reviewed retrospectivety 77 cases of PGCG from 62 patients, from our files with respect to incidence, sex, patient age, race, clinical symptoms and signs, radio-graphic features and recurrence following excision.
RESULTS AND CONCLUSIONS: Our results were largety in agreement with previous reports, although there is wide variation in the results published between series. In addition, some clinical features of PGCG are poorly defined. Little is known about the retative incidences of PGCG and central giant cell granuloma. An association between PGCG and tooth loss may exist, but is poorly defined, and not all PGCG that involve edentulous areas follow recent tooth loss. Information about PGCG recurrence after excision is limited, and does not necessarily follow incomplete excision. Despite the large number of reported cases of PGCG, clarification of some clinical features is required, and may hetp formulation and interpretation of future laboratory-based research into this poorly understood lesion. 相似文献
907.
PA Reichart 《Oral diseases》1997,3(Z1):S180-S182
Oral ulceration in HIV infection may be due to: (1) mycotic; (2) bacterial, protozoan; (3) and viral infections; (4) oral neoplasia; (5) aphthous ulceration/ulceration not otherwise specified (NOS); or (6) ulceration of iatrogenic origin. Of particular significance are oral ulcerations caused by viruses of the herpes virus group (HSV 1/2, CMV, VZV) and ulcerations of the aphthous type. It was shown recently that coinfection of viral ulcers occurs. The aetiopathogenesis of the aphthous type of ulcerations including the still debated ulceration NOS is not clear. Further basic and clinical research is necessary in order to better understand ulceration particularly in relation to immunoregulation, tissue breakdown and repair. 相似文献
908.
909.
Ohno K; Quiram PA; Milone M; Wang HL; Harper MC; Pruitt JN nd; Brengman JM; Pao L; Fischbeck KH; Crawford TO; Sine SM; Engel AG 《Human molecular genetics》1997,6(5):753-766
We describe and functionally characterize six mutations of the
acetylcholine receptor (AChR) epsilon subunit gene in three congenital
myasthenic syndrome patients. Endplate studies demonstrated severe endplate
AChR deficiency, dispersed endplate regions and well preserved junctional
folds in all three patients. Electrophysiologic studies were consistent
with expression of the fetal gamma-AChR at the endplates in one patient,
prolongation of some channel events in another and gamma- AChR expression
as well as some shorter than normal channel events in still another.
Genetic analysis revealed two recessive and heteroallelic epsilon subunit
gene mutations in each patient. One mutation in each (epsilonC190T [epsilon
R64X], epsilon 127ins5 and epsilon 553del 7) generates a nonsense codon
that predicts truncation of the epsilon subunit in its N-terminal,
extracellular domain; and one mutation in each generates a missense codon
(epsilon R147L, epsilon P245L and epsilon R311W). None of the mutations was
detected in 100 controls. Expression studies in HEK cells indicate that the
three nonsense mutations are null mutations and that surface expression of
AChRs harboring the missense mutations is significantly reduced. Kinetic
analysis of AChRs harboring the missense mutations show that epsilon R147L
is kinetically benign, epsilon P245L prolongs burst open duration 2-fold by
slowing the rate of channel closing and epsilon R311W shortens burst
duration 2-fold by slowing the rate of channel opening and speeding the
rate of ACh dissociation. The modest changes in activation kinetics are
probably overshadowed by reduced expression of the missense mutations. The
consequences of the endplate AChR deficiency are mitigated by persistent
expression of gamma-AChR, changes in the release of transmitter quanta and
appearance of multiple endplate regions on the muscle fiber.
相似文献
910.
Merriman TR; Eaves IA; Twells RC; Merriman ME; Danoy PA; Muxworthy CE; Hunter KM; Cox RD; Cucca F; McKinney PA; Shield JP; Baum JD; Tuomilehto J; Tuomilehto- Wolf E; Ionesco-Tirgoviste C; Joner G; Thorsby E; Undlien DE; Pociot F; Nerup J; Ronningen KS; Bain SC; Todd JA 《Human molecular genetics》1998,7(3):517-524
Allelic association methods based on increased transmission of marker
alleles will have to be employed for the mapping of complex disease
susceptibility genes. However, because the extent of association of single
marker alleles with disease is a function of the relative frequency of the
allele on disease-associated chromosomes versus non disease-predisposing
chromosomes, the most associated marker allele in a region will not
necessarily be closest to the disease locus. To overcome this problem we
describe a haplotype-based approach developed for mapping of the putative
type 1 diabetes susceptibility gene IDDM6. Ten microsatellite markers
spanning a 550 kb segment of chromosome 18q21 in the putative IDDM6 region
were genotyped in 1708 type 1 diabetic Caucasian families from seven
countries. The most likely ancestral diabetogenic chromosome was
reconstructed in a stepwise fashion by analysing linkage disequilibrium
between a previously defined haplotype of three adjacent markers and the
next marker along the chromosome. A plot of transmission from heterozygous
parents to affected offspring of single marker alleles present on the
ancestral chromosome versus the physical distance between them, was
compared with a plot of transmission of haplotypes of groups of three
adjacent markers. Analysing transmission of haplotypes largely negated
apparent decreases in transmission of single marker alleles. Peak support
for association of the D18S487 region with IDDM6 is P = 0.0002 (corrected P
= 0.01). The results also demonstrate the utility of polymorphic
microsatellite markers to trace and delineate extended and presumably
ancient haplotypes in the analysis of common disease and in the search for
identical-by-descent chromosome regions that carry an aetiological variant.
相似文献