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151.
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Although arthrocentesis is not a panacea, it has been widely used for a variety of temporomandibular joint (TMJ) disorders. Uncritical acceptance of the procedure has been cautioned against, as further analysis and clarification of published studies was required. The aim of this article was to review the efficacy of arthrocentesis in the treatment of patients with TMJ closed lock. The rationale behind this approach was based on the notion that TMJ surgical results should be reported by the specific category of TMJ disorder. After a Medline search of the international literature, 14 articles were found fulfilling the criteria set forth by this article. Another five articles were added after an additional hand search based on the available references of the papers found. The majority of the reviewed publications were prospective case series with flawed methodology and, despite the impression that arthrocentesis may be beneficial for patients with TMJ closed lock, there have been no good prospective randomized clinical trials that confirm the efficacy of this procedure.  相似文献   
154.
The symptoms of most endocrine system diseases are usually clearly recognizable and most of the times are accompanied by a rich medical history. Many general practitioners are reluctant to treat such cases and prefer to refer these patients to specialists who are trained in management of the medically compromised thus increasing the chances of dental treatment without complications. However, sometimes endocrinal diseases develop slowly and their clinical manifestations are hidden or subclinical in nature. In these cases, neither the patient nor the dentist are aware of the condition and there is the potential of life threatening, emergency situations in what at first seem as simple, straightforward dental procedures. Therefore, the dentist must be able to recognize the clinical problem, differentiate between the different symptoms and initiate the proper management protocol. The most unstable endocrinal disorders that should be treated with great care are diabetes mellitus, mainly hypoglycemia, hyperthyroidism and adrenal insufficiency. The general practitioner dentist can treat patients suffering from these disorders providing the disease is well controlled and balanced and that the dental treatment is not very traumatic.  相似文献   
155.
BACKGROUND AND AIMS: A limited amount of data using flat trim multitufted toothbrushes shows that abrasion of substrate surfaces by a standard toothpaste varies dependent on filament stiffness and configuration; soft brushes producing the most abrasion. The aims of these studies in vitro were to assess toothpaste abrasion of acrylic and stain removal by 5 proprietary medium toothbrushes with different head filament arrangements, and a prototype brush with rectangular filaments. The prototype brush had a medium texture in the long axis and soft texture at right angles to the long axis. MATERIAL AND METHOD: Optically clear acrylic was used as the substrate for abrasion by a standard toothpaste. Loss of substrate was determined by profilometry after 5000, 10000, 15000 and 20000 linear or rotary brushing actions. Stain removal was determined spectrophotometrically from optically clear acrylic specimens stained by chlorhexidine tea soaking sequences. Stained specimens were brushed with water using linear or rotary actions and measurements taken every 10 s to 60 s. RESULTS: Abrasion was progressive with increasing strokes and the pattern for each brush and brush action was to a first approximation linear. Overall, abrasion was significantly greater with linear compared to rotary action. Also overall brushes differed in the abrasion produced with both actions and particularly at greater exposure times. Within brush differences for the two motions were all significant by 20000 strokes except for the prototype brush. Stain removal was progressive over time with each brush but the pattern was non-linear. For the proprietary brushes the rotary motion removed less stain. For the prototype brush more stain was removed with the rotary action. Overall brushes differed significantly in stain removal within each motion and for each motion most differences between the proprietary and prototype brushes reached significance. CONCLUSIONS: The differences between brushes for both abrasion and stain removal must in large part relate to the filament contact area with the substrate surface. Whilst the model may not be predictive of clinical differences, it could find use to establish minimum criteria for toothbrush action.  相似文献   
156.
An intraindividual comparative study of proximal tibial marrow defects in nine adult Goettinger miniature pigs (GMPs) was undertaken. The left side of the defect was filled with granular beta-tricalcium phosphate (TCP) ceramic ad modum Cerasorb, and the right side was filled with granular alpha-TCP ceramic ad modum Biobase alpha pore. Simultaneously, dental screw implants were inserted in each ceramic and fixed within the orthotopically replanted corticalis lids. Control defects were made in two other animals. The survival period ranged from 4 to 86 weeks (control study, 16 and 20 weeks). The reorganization and degree of bone regeneration, dynamics of ceramic degradation, and remodeling characteristics of the bone regenerate referring to osseo-integration of the dental implants were examined histomorphologically in nondecalcified specimens. The results reveal that both ceramic types were osteoconductive exclusively. Centripetally oriented angiogene bone regeneration occurred at the margins of the circular defects. Ceramic degradation was performed hydrolytically and within cells. Furthermore, it was demonstrated that decomposition of the intratrabecularly integrated ceramic residues underlies a dynamic process of degradation. Within 86 weeks, nearly 80% to 90% of the larger alpha-TCP granules, and nearly 90% to 95% of the beta-TCP granules were degraded. At this time, especially for the alpha-TCP modification, ceramic microparticles were found in the marrow, either unbound or within polynuclear macrophages. The predictable degradation of both ceramic types provides an early functional adaptation of bone regenerates and facilitates a biofunctional, anisotropic orientation of the neotrabeculae without delay. It is concluded that because of the initially pronounced accumulation of macrophages, dental implants should not be inserted simultaneously with ceramic, but after further progress of ceramic degradation (5 to 6 months after TCP implantation).  相似文献   
157.
The applicability of endosseous implants is directly related to the topography and quality of the patient's residual bone. Several techniques have tried to expand the applicability through implant design alterations and surgical techniques for bone augmentation. This article describes an implant-induced bone expansion procedure that facilitates the placement of implants in atrophic alveolar ridges. This procedure expands the cortical plates of the alveolar ridges with or without fracture using wedge-shaped implants and the principles of guided tissue regeneration. The use of implants of larger diameters and the remodeling of the ridge external contour can be achieved with this procedure.  相似文献   
158.
This paper presents a retrospective study carried out on a sample of 100 patients affected by pleomorphic adenoma of the parotid gland and treated at the Department of Maxillofacial Surgery at the University of Rome "La Sapienza" between January 1, 1989 and December 31, 1997. For the diagnosis of this neoformation, cytological tests were performed on material taken from the neoformation using fine needle aspiration and ultrasound scan. In some selected cases, a CT examination of the head and neck with medium contrast or Nuclear Magnetic Resonance (NMR) was carried out. This study sets out to examine the most suitable treatment to be followed for the removal of the pleomorphic adenoma of the parotid gland. In 56 cases the patients underwent a superficial, conservative parotidectomy. Forty one patients had a total parotidectomy with the facial nerve left intact and one patient had a total parotidectomy where the marginal mandibular nerve of the facial nerve was damaged. The remaining two patients involved in the study were suffering from a recurrent pleomorphic adenoma and in these two cases a total parotidectomy was performed where the facial nerve was killed. The removal of the cranial nerve VII in these patients proved necessary because the nerve fibers had adhered to the surrounding scar tissue of the tumor, either after previous surgery or due to repeated chronic phlogosis of the gland.  相似文献   
159.
Age-associated changes in decorin in rat mandibular condylar cartilage   总被引:3,自引:0,他引:3  
The small proteoglycan decorin strongly binds the fibrils of collagen types I and II; this interaction is thought to play a part in the maintenance of tissue integrity and biomechanical properties. In limb articular cartilage, there is evidence that decorin synthesis increases with age and that it is elevated in response to increased loading or in osteoarthritic cartilage. The aim here was to characterize the presence and relative amount of decorin in the condylar cartilage of the temporomandibular joint (TMJ) with maturation by Western blotting, and to assess its tissue localization by immunohistochemistry. Comparative data were obtained from tibial articular cartilage, which has been extensively studied. Cartilage from the mandibular condyle and tibial plateau was harvested from 24-day-old (growing) and 161-day-old (young adult) female Sprague-Dawley rats. In growing animals, decorin appeared slightly more abundant in the mandibular condylar cartilage than in articular cartilage, whereas in young adult animals the decorin content in the TMJ cartilage was noticeably less than in limb articular cartilage. Although there was an increase in decorin abundance with age at the TMJ, the increase in decorin with age in limb articular cartilage was considerably more pronounced. These data indicate that, although decorin is present in mandibular condylar cartilage, its abundance in adults is less than in limb articular cartilage; thus, maturation-associated changes may be dissimilar in magnitude from those documented for limb articular cartilage.  相似文献   
160.
A 14-year-old girl was referred to our clinic with a problem of a painless slow growing lesion for approximately three years. MR imaging findings of lesion was "retention cyst of the salivary gland". Controversially, the histological examination of the total excised specimen was "neurinoma" and that was inconsistent with MR findings. Neural tissue tumors of the oral cavity are rare, however, this diagnosis was confirmed by surgical excision and histopathological examination. There was a rare location of the lesion as well.  相似文献   
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