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141.
Radiation caries. A review and SEM study 总被引:1,自引:0,他引:1
142.
It has been reported that little diagnostic information concerning periodontal conditions is entered in patient records of general practitioners, but actual rates for such chart entries are unknown. Records of regular patients, seen at least annually, were randomly selected from the offices of 36 general practitioners in two North Carolina counties. In each office 80 records were selected for audit. After adjustment, the final sample consisted of 2488 audited records. Entries noting the presence or absence of 14 diagnostic conditions were identified for the five previous years and for the patient's most recent examination. The presence of a periodontal diagnosis or periodontal treatment plan was noted. The number of radiographic sets exposed in the previous five years and the age of the most recent set were determined for complete series/panoramic films and for bitewings. Across practices, the most frequent notations (20.5% within the past five years) concerned the presence of probing depths and calculus. Gingival bleeding (13%) and plaque (12%) were noted less frequently. A periodontal diagnosis was recorded in only 16.3% of the records. Annualized rates for radiographic sets were 0.09 for complete series/panoramic films and 0.50 for bitewings. These data suggest that, except for radiographs, the majority of patient records do not contain sufficient diagnostic information to describe patients' periodontal health. 相似文献
143.
J. B. Payne G. K. Johnson R. A. Reinhardt J. K. Dyer C. A. Maze D. G. Dunning 《Journal of periodontal research》1996,31(2):99-104
Cigarette smoking is a major risk factor in the development and further progression of periodontitis. However, little is known regarding the pathogenesis of smoking-related periodontal diseases. The purpose of this study was to examine the effects of nicotine, alone and in combination with lipopolysaccharide (LPS), on monocyte secretion of bone-resorbing factors, PGE2 and IL-1β. Peripheral blood monocytes (PBM) were isolated by counterflow centrifugal elutriation from 15 healthy, non-smoking donors. PBM were incubated for 24 h in RPMI 1640 containing nicotine (0, 50 μg/ml, I μg/ml, 10 μg/ml and 100 μg/ml) with or without 10 μg/ml Porphyromonas gingivalis LPS or Escherichia coli LPS. Culture supernatants were assayed for PGE2 and IL-1β by ELISA. None of the nicotine preparations resulted in significant PBM secretion of PGE2 and IL-1β above that of unstimulated cultures. However, PGE2 release was potentiated 1.7-fold by the combination of P. gingivalis LPS and 10 μg/ml nicotine relative to P. gingivalis LPS alone (p<0.05, one-way ANOVA). Prostaglandin E3 release also was potentiated 3.5-fold by P. gingivalis LPS and 100 μg/ml nicotine relative to P. gingivalis LPS alone (p<0.00001, one-way ANOVA) and 3.1-fold by E. coli LPS and 100 μg/ml nicotine relative to E. coli LPS alone (p<0.00001, I. one-way ANOVA). IL-1β secretion was lower for either LPS plus 100 μg/ml nicotine relative to LPS alone, although not significantly. These data demonstrate upregulation of LPS-mediated monocyte secretion of PGE2 by nicotine and suggest a potential role for nicotine in periodontal disease pathogenesis. 相似文献
144.
Although a wide range of bacterial species has been isolated from infected dental root canals it remains necessary to determine whether any particular group of such bacteria is associated with specific endodontic symptoms and clinical signs. In this study 30 root canals were examined microbiologically; of these, 14 were associated with pain, 20 with tenderness to percussion, 23 presented with wet root canals, seven with swelling, five with purulent exudate and four with a sinus. Clinical and microbiological correlation was observed particularly with regard to pain where anaerobes were isolated from 93% of painful canals and only from 53% of painfree canals. The former yielded means of 2.5 anaerobic species and 1.6 facultative species per canal, compared with 1.5 and 2.4 in painfree canals. Prevotella spp. were isolated from 64.2% of painful canals and 12.5% of painless canals (P<0.01) similarly, peptostreptococci were isolated from 71.4% of painful and 31.3% of painless canals (P<0.05). It was concluded that a significant association exists between pain and the presence of Prevotella and Peptostreptococcus spp. in dental root canals. 相似文献
145.
The number of teeth needed to maintain adequate dental function in older adults is unknown. The purpose of this study was to examine the relationship between oral function and the number of opposing pairs of posterior teeth. We identified 338 subjects with complete anterior dentitions from an interview and examination survey of Ontario adults aged 50 and over; 261 had no partial denture and 77 had removable partial dentures (RPD). Oral function was measured using questions assessing chewing ability, mandibular function and socio-psychological impact.
Subjects with no partial dentures were further allocated to five groups, based on their dental status: complete dental arch ( n = 69); 5–7 functional units-pairs of opposing posterior teeth ( n = 109); 3 or 4 functional units ( n = 48) and 0–2 functional units ( n = 35). Oral function problems increased with decreasing functional units being markedly more prevalent among the groups with 0–2 functional units. 34% of subjects in the 0–2 group reported one or more problems with chewing ability compared to 6–17% in the other groups (χ2 P = 0.001 d.f. = 3).
The 77 subjects who wore removable partial dentures, reported social and dental function at levels comparable to those with no dentures.
From these results, there appears to be little socio-functional need to replace lost posterior teeth with a partial denture until the person has fewer than, 3 posterior functional units. The low number of partial denture wearers limited our ability to detect a lasting benefit from RPD treatment. 相似文献
Subjects with no partial dentures were further allocated to five groups, based on their dental status: complete dental arch ( n = 69); 5–7 functional units-pairs of opposing posterior teeth ( n = 109); 3 or 4 functional units ( n = 48) and 0–2 functional units ( n = 35). Oral function problems increased with decreasing functional units being markedly more prevalent among the groups with 0–2 functional units. 34% of subjects in the 0–2 group reported one or more problems with chewing ability compared to 6–17% in the other groups (χ
The 77 subjects who wore removable partial dentures, reported social and dental function at levels comparable to those with no dentures.
From these results, there appears to be little socio-functional need to replace lost posterior teeth with a partial denture until the person has fewer than, 3 posterior functional units. The low number of partial denture wearers limited our ability to detect a lasting benefit from RPD treatment. 相似文献
146.
F G Oppenheim D I Hay D J Smith G D Offner R F Troxler 《Journal of dental research》1987,66(2):462-466
Acidic proline-rich phosphoproteins and phosphopeptides are abundant components of parotid and submandibular salivary secretions in man and in the subhuman primate, Macaca fascicularis. The major acidic proline-rich proteins and the proline-rich phosphopeptide, statherin, of man and macaques have been shown to be potent inhibitors of calcium phosphate precipitation and are thought to function in the oral environment by maintaining saliva supersaturated with respect to calcium phosphate salts. Little is known about the biosynthesis of these proline-rich phosphoproteins and peptides, and the aim of the present work was to determine the structural relationship between statherin precursors and native human and macaque statherin. RNA was isolated from human submandibular gland, and poly(A+) mRNA was selected by affinity chromatography on oligo(dT) cellulose and translated in a reticulocyte lysate. Electrophoretic analysis of the translation products revealed that this mRNA directed the synthesis of a large number of polypeptides with Mrs ranging from 5000 to 70,000. Immunoprecipitates, prepared with an antiserum directed against human statherin, contained a single component with a Mr of 7800, approximately 2000 daltons larger than native statherin. Radiosequencing of the in vitro precursor of statherin in immunoprecipitates demonstrated the presence of a 19-residue signal peptide. These results suggest that statherin is derived from a unique structural gene, and does not result from proteolytic processing of a large polyprotein precursor. 相似文献
147.
Tongues from young, old and senescent Swiss-Webster white mice were compared. Sections and tissues were taken from the anterior, posterior, and ventral regions. The epithelium became atrophic and hyperkeratotic in the senescent animals. The filiform papillae were blunted, atrophic and disorganized across the entire dorsal surface in the older animals. The ventral aspect in the senescent animals had thinning epithelium, a hyperchromatic germinal layer, and a roughened, disorganized surface. 相似文献
148.
Keratin proteins in human oral mucosa 总被引:2,自引:0,他引:2
We have examined the keratin proteins in normal human oral mucosa from 6 different regions including hard palate, buccal mucosa, tongue, gingiva and floor of the mouth. Urea-dithiothreitol extracts of EDTA separated epithelia were analysed by SDS-PAGE and immunoblotting. Eight samples from each region were investigated and showed very little individual variation in the keratin profile on Coomasie Blue-stained gels. The keratinizing hard palate and gingiva expressed identical patterns and resembled the pattern of epidermis from the flank region. The normally non-keratinizing buccal mucosa and the mucosa of the floor of the mouth expressed polypeptides distinctly different from those of the keratinizing epithelia and lacked the high molecular weight keratins. The dorsal surface of the tongue and the commissure region showed a pattern intermediate between keratinizing and non-keratinizing epithelia. The greater sensitivity of the immunoblotting technique revealed that the non-keratinizing epithelia synthesized one of the high molecular polypeptides and that the tongue produced all the bands found in keratinizing epithelia, but in very small quantities. There are, thus, distinct differences in the keratin expression of oral epithelia which are related to the pattern of keratinization assessed histologically. 相似文献
149.
D J Rosenberg A L Koch S Cretin M H Schoen M Marcus 《Journal of dental education》1986,50(11):665-672
Increased time to treat the special patient is often cited as a barrier to dental care. The purpose of this study was to analyze the separate and combined effects of differences in dental services planned, services actually performed, and differences in treatment time requirements between special and nonspecial patients in a hospital ambulatory clinical setting. Data for this study were obtained from the UCLA evaluators of the RWJ-funded Hospital-Sponsored Ambulatory Dental Services Program (HSADSP). The results show that special patients require more dental treatment than nonspecial patients for advanced dental disease (i.e., periodontics, surgery, and removable prosthetics) and that they receive more of such services. The study also found that special patients should not be viewed as a homogeneous group when evaluating dental needs and required time resources for treatment. Three subgroups of special patients were identified: developmentally disabled, severely compromised, and moderately compromised. The developmentally disabled as compared to the nonspecial patients required significantly more (20 percent) provider time in completing a "representative" treatment plan. 相似文献
150.
An in vivo comparison was made of three different types of restorative resins: a conventional composite resin, a chemically cured microfilled resin, and a small-particle, glass-filled, visible light-cured composite resin. Twenty-eight sets of three restorations were placed 20 patients and examined using the Ryge rating system. All resins performed well and were not significantly different from one another at 1 year. After 3 years, all materials were considered satisfactory, but the conventional composite resins had significantly more surface roughness than did the other resins. Each of the resin materials also declined in color match after 3 years. 相似文献