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Bolontrade MF; Stern MC; Binder RL; Zenklusen JC; Gimenez-Conti IB; Conti CJ 《Carcinogenesis》1998,19(12):2107-2113
In this study we have analyzed the vascular response induced in the two-
stage carcinogenesis model in SENCAR mice. The role of angiogenesis has not
been explored in this model, which is the paradigm of multistage
carcinogenesis and a model for neoplastic lesions derived from exophytic
premalignant lesions (e.g. colon carcinoma, bladder papilloma). We
investigated if angiogenesis is involved in the formation of papillomas and
in the progression from papilloma to carcinoma. To this end we analyzed the
vasculature of normal and hyperplastic skin, focal epidermal hyperplasias
that are precursors of papillomas, papillomas at different stages and
squamous cell carcinomas. We also analyzed the vascularization of
papillomas induced in two strains of mice that differ in their
susceptibility to malignant progression. We show here that angiogenesis is
turned on in the earliest stages of papilloma formation. In late stages,
regardless of state of progression, the predominant response is an increase
in the size of blood vessels. Thus, in the SENCAR mouse model,
representative of exophytic tumors, the angiogenesis switch is a very early
event, probably mechanistically related to the development of the primarily
exophytic lesions. Therefore, the density of blood vessels cannot be used
as a predictor of malignant progression in this model.
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Northridge ME Chakraborty B Kunzel C Metcalf S Marshall S Lamster IB 《Journal of public health dentistry》2012,72(3):235-245
Objectives: As part of ongoing efforts by the Columbia University College of Dental Medicine to devise community‐based models of health promotion and care for local residents, we sought to answer the following query: “What contributes to self‐rated oral health among community‐dwelling older adults?” Methods: The present study is cross sectional in design and centrally concerned with baseline data collected during community‐based screenings of adults aged 50 years and older who agreed to participate in the ElderSmile program in northern Manhattan, New York City. The primary outcome measure of interest is self‐rated oral health, which was assessed as follows: “Overall, how would you rate the health of your teeth and gums – excellent, good, fair, or poor?” Results: More than a quarter (28.5 percent) of ElderSmile participants aged 50 years and older reported that their oral health was poor. After adjustment for age (in years), place of birth, educational level, and dental insurance status in a logistic regression model, recent visits to the dentist (within the past year versus more than a year ago) contributed to better self‐rated oral health and non‐Hispanic Black race/ethnicity, dentate (versus edentulous) status, tooth decay as measured by decayed missing filled teeth, and severe periodontal inflammation contributed to worse self‐rated oral health in this population. Conclusions: Recent dental care contributed to better self‐rated oral health among community‐dwelling older adults living in northern Manhattan. Significant gradients were evident in the caries experience and periodontal inflammation of dentate adults by self‐rated oral health, suggesting that untreated oral disease contributes to poor self‐rated oral health. 相似文献
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The polyamines putrescine, spermidine and spermine in human gingival crevicular fluid 总被引:1,自引:0,他引:1
In human periodontal disease, there may be periods of exacerbation and remission. Definition of the homeostatic mechanisms in the periodontium may therefore be important in understanding the natural history of this disorder. The polyamines are biologically active amines involved in the regulation of cell growth, regeneration of tissue and modulation of inflammation. Their occurrence was examined in gingival crevicular fluid (GCF). Fifteen sites were evaluated in four patients with moderately advanced periodontitis before and after root planing and scaling, and 15 sites were evaluated in four patients with mild inflammatory gingivitis and no attachment loss. Polyamine analysis was by high-performance liquid chromatography. GCF from untreated sites in periodontitis patients contained the highest concentration of putrescine (10(4) greater than serum). This polyamine was detected in all periodontitis samples and 12 of 15 gingivitis samples. Significant differences were seen when the amount of putrescine/30 s sample was compared: periodontitis sites before treatment 1005.7 +/- 106.1 pmol; periodontitis sites after treatment 504.7 +/- 89.2 pmol; gingivitis sites 186.7 +/- 40.1 pmol. In contrast, spermidine and spermine were detected only occasionally. Thus putrescine may play an important homeostatic role in the periodontium. 相似文献
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Periodontitis is a common disorder affecting >40% of adults in the United States. Globally, the severe form of the disease has a prevalence of 11%. In advanced cases, periodontitis leads to tooth loss and reduced quality of life. The aetiology of periodontitis is multifactorial. Subgingival dental biofilm elicits a host inflammatory and immune response, ultimately leading to irreversible destruction of the periodontium (i.e. alveolar bone and periodontal ligament) in a susceptible host. In order to successfully manage periodontitis, dental professionals must understand the pathogenesis, primary aetiology, risk factors, contributing factors and treatment protocols. Careful diagnosis, elimination of the causes and reduction of modifiable risk factors are paramount for successful prevention and treatment of periodontitis. Initial non-surgical periodontal therapy primarily consists of home care review and scaling and root planing. For residual sites with active periodontitis at periodontal re-evaluation, a contemporary regenerative or traditional resective surgical therapy can be utilised. Thereafter, periodontal maintenance therapy at a regular interval and long-term follow-ups are also crucial to the success of the treatment and long-term retention of teeth. The aim of this review is to provide current concepts of diagnosis, prevention and treatment of periodontitis. Both clinical and biological rationales will be discussed. 相似文献
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A case of infantile agranulocytosis with survival into adolescence is presented. The polymorphonuclear leukocyte is considered an important source of lysosomal enzymes in gingival crevicular fluid, and evaluation of connective tissue-degrading enzymes in the fluid was performed. The activity of beta-glucuronidase, a ground substance-degrading enzyme that may serve as a marker for polymorphonuclear leukocytes, was markedly reduced in the fluid compared to samples from systemically healthy adults with periodontitis. The activities of the ground substance-degrading enzyme arylsulfatase, and collagenase, were in the low-normal range. The plaque microbiology, as characterized by dark-field microscopy and selective culturing, was consistent with advanced periodontitis. A review of the medical history revealed a series of bacterial infections since infancy. Improvement in the systemic health of the patient occurred at about the age of 15, and the intake of antibiotics to control infections was correspondingly reduced after this time. An exacerbation of the patient's periodontal disease, as evaluated by loss of alveolar bone on radiographs, occurred 1 to 2 years later. The progression of periodontal disease observed in this patient was apparently associated with the withdrawal of antibiotics administered for control of systemic (nonoral) infections. 相似文献