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排序方式: 共有762条查询结果,搜索用时 15 毫秒
81.
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Gradient-echo MR imaging: techniques and acronyms 总被引:3,自引:0,他引:3
83.
AC Katoulis† NG Stavrianeas† S Georgala‡ E Bozi† D Kalogeromitros† E Koumantaki‡ AD Katsambas‡ 《Journal of the European Academy of Dermatology and Venereology》2005,19(4):444-448
BACKGROUND: Although a common dermatosis, idiopathic poikiloderma of the face and neck has not been studied in depth for decades. OBJECTIVES: To reassess the clinical and epidemiological characteristics of poikiloderma of Civatte (PC). MATERIAL AND METHODS: Fifty consecutive patients with PC. Evaluation included history taking and physical examination. Epidemiological and clinical parameters were recorded and analysed. The literature from 1923 until today, was reviewed thoroughly. RESULTS: The frequency of PC among dermatologic patients was estimated to be 1.4%. There were 34 females (68%) and 16 males in the present study. The mean age at diagnosis was 47.8 years for females and 61.7 years for males. The majority (88%) had skin phototype II or III. Among females, 26 were at their peri-menopausal stage, including three cases of iatrogenic menopause. Four patients reported that other blood-related family members also had PC. The v and the sides of the neck and the upper chest were most often affected in a symmetric distribution. The face (preauricular and parotid region) was involved in 19 patients (38%). The erythemato-telangiectatic clinical type predominated (58%), followed by the mixed (22%) and the pigmented type (20%). Almost half of the patients (46%) were symptomatic (itching, burning and 'flushing'). The mean duration from onset to diagnosis was 6.2 years according to the patients' report. The course was usually slowly progressive (82%) and irreversible. CONCLUSIONS: PC shows characteristic features, supporting the theory that it represents a distinct entity. It is rather common in Greece. Although menopausal women predominated in our cohort, men were not uncommonly affected and were diagnosed at an older age. Based on the predominating clinical feature, PC can be classified into three clinical forms. Symmetry and sparing of the anatomically shaded areas of the neck are highly characteristic for PC. Face involvement was not as common and as severe as it had been considered in the past. Recognition of clinical type is important for the selection of the most appropriate treatment, which, despite the advent of novel modalities, remains problematic. 相似文献
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Daniel T. McDevitt MD Joann M. Lohr MD Kevin D. Martin MD Richard E. Welling MD Michael G. Sampson AD 《Annals of vascular surgery》1993,7(3):282-286
An 82-year-old man was admitted with a left hip fracture sustained in a fall. The fracture was surgically repaired. Ipsilateral leg swelling developed over the following 2 weeks. A lower extremity venous duplex scan demonstrated isolated dilatation of the popliteal veins in both lower extremities. Chronic thrombosis was noted in both popliteal veins at the level of this dilatation. Initial duplex scanning also revealed acute thrombus in the left popliteal, posterior tibial, and peroneal veins. A repeat scan 1 week later identified propagation of thrombus into the superficial femoral vein. Popliteal vein aneurysms, although rare, can cause significant morbidity and mortality. The literature is also reviewed.Presented at the Second Annual Winter Meeting of the Peripheral Vascular Surgery Society, Breckenridge, Colo., January 25–27, 1992. 相似文献
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Objective: The study aimed to determine if multiple displacement amplification could be used to provide abundant target DNA and DNA probes for checkerboard DNA–DNA hybridization. Methods: Multiple displacement amplification was used to amplify 1 and 10 ng DNA from 16 individual bacterial species, DNA from single colonies, from a mixture of 20 bacterial species and oral biofilm samples, such as supragingival plaque, subgingival plaque, buccal swab and root canal samples. Samples in reaction buffer were heat‐denatured at 95°C for 3 min and cooled to 4°C. Φ29 DNA polymerase was added and the mixture was incubated at 30°C for 16–18 h. The quantity of the product was evaluated by the Picogreen assay. The amplified material was labeled with digoxigenin. The probes were compared with probes obtained from unamplified DNA using checkerboard DNA–DNA hybridization. Both amplified DNA and unamplified DNA were used as targets on the membrane. Amplified oral biofilm samples were compared to unamplified samples using checkerboard DNA–DNA hybridization. Results: The DNA yield ranged from 4 to 11 μg. DNA–DNA hybridization showed that the amplified genome of each species used either as target or as probe provided signals equivalent to controls and that amplification of a mixture of species provided signals comparable to those provided by the unamplified source mixture. Amplified oral biofilm samples exhibited comparable proportions of bacterial DNA when compared to the original unamplified samples. Conclusions: The multiple displacement amplification technique is a simple and reliable method to uniformly amplify DNA for use in checkerboard DNA–DNA hybridization. It is also a useful tool in the amplification of clinical samples. 相似文献
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T. Yoneyama H. Okamoto J. Lindhe S. S. Socransky A. D. Haffajee 《Journal of clinical periodontology》1988,15(9):581-591
The present investigation describes probing pocket depth, probing attachment level and recession data from 319 randomly selected subjects, aged 20-79 years, from Ushiku, Japan. The findings are reported as mean values, frequency distributions and percentile plots of the 3 parameters at buccal, interproximal and lingual surfaces of single rooted (incisors, canines, premolars) and molar teeth. Inter-as well as intra-examiner errors for probing pocket depth and probing attachment levels were assessed and found to be small. The data reported revealed that practically all subjects studied had one or more sites in the dentition affected by destructive periodontal disease and that the severity of disease increased with age. It was further observed that in each age group, molars had suffered more attachment loss than single rooted teeth and that the interproximal surfaces as a rule had lost more periodontal tissue support than corresponding buccal and lingual surfaces. The attachment loss difference observed between different surfaces of a given tooth or a group of teeth, however, was comparatively small. In the age groups between 20-59 years, advanced destructive periodontal disease was found in a small subgroup of the subject sample, while after the age of 60 years, widespread destructive periodontitis was common. An attempt was made to examine the progression of destructive disease with age by comparing the frequency distributions of sites with attachment loss of greater than or equal to 3 mm in subjects of different age groups. The data suggested that in younger subject groups, progression was confined to a subset of individuals, while in older age groups, more subjects and sites became involved. A major feature of destructive periodontal disease in older individuals was the accompaniment of attachment loss with recession at the gingival margin. Deep pockets were relatively infrequently detected, while advanced loss of attachment (with recession) occurred at many sites. 相似文献