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11.
Carlotta Castagnoli Claudia Trombotto Sabzima Ondei Maurizio Stella Maurizio Calcagni Gilberto Magliacani Simone Teich Alasia 《Burns : journal of the International Society for Burn Injuries》1997,23(7-8):565-572
In this study, skin-infiltrating cells were characterized in both the active and remission phases of post-burn hypertrophic scar biopstes. Immunohistochemistry examination of active phase samples showed an abundant presence of Langerhans cells, T cells, macrophages, a low presence of natural killer cells and the lack of B lymphocytes. In active hypertrophic scars T lymphocytes infiltrate deep into the superficial dermis and are also observed in the epidermis: CD3+ cells were present at about 222±107 per 0.25 mm2. In particular the analysis of lymphocyte subpopulations showed that CD4+ T cells predominate in the dermis as well as in the epidermis of active hypertrophic scars whereas CD8+ cells were less well represented (CD4/CD8 ratio is 2.06). This distribution was also shown in remission phase samples and in normotrophic scar specimens, although the lymphocyte number was significantly lower. Approximately 70 per cent of T lymphocytes present in the tissue involved in active phase hypertrophic scar samples were activated (positive with anti-HLA-DR and IL-2 receptor antibodies) which is significantly higher than remission phase hypertrophic and normotrophic scars, in which positivity was 40 and 38 per cent, respectively. Upon activation, the lesional lymphocytes release several cytokines, locally and transiently, that interact with specific receptors in response to different stimulation. Central to the immune hypothesis of hypertrophic scars is that some of the T-cell lymphokines act on keratinocytes, fibroblasts and other cell types to induce changes characteristic of these scars. The presence and close proximity of activated T lymphocytes and antigen-presenting cells of various phenotypes in both the epidermis and dermis of hypertrophic tissues provides strong circumstantial evidence of a local immune response. However, the manner in which T cells achieve and maintain their activated state in hypertrophic tissues in not yet known, and both antigen-dependent and independent mechanisms may contribute. 相似文献
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During aging there are several structural, functional and biochemical alterations, including changes in macromolecular composition and turnover. Regulation of gene expression, DNA and RNA synthesis, total poly(A)+ and poly(A)- RNA contents, qualitative and quantitative changes of synaptosomal plasma membrane proteins, diminished plasticity, loss of synapses, lower rate of axoplasmic transport, impairment of antioxidant and bioenergetic systems seem to be involved in the aging process of nervous system. 相似文献
14.
Reducing the Occupational Risk of Infections for the Surgeon: Multicentric National Survey on More Than 15,000 Surgical Procedures 总被引:2,自引:0,他引:2
Andrea Pietrabissa Stefano Merigliano Marco Montorsi Gilberto Poggioli Marco Stella Domenico Borzomati Enrico Ciferri Giuseppe Rossi Gianbattista Doglietto 《World journal of surgery》1997,21(6):573-578
The objective of this study was to find the incidence of accidental exposures to blood and body fluids among surgeons during operations and to describe their dynamics. A probabilistic model was also used to predict the cumulative 30-year risk to the surgeon of contracting hepatitis B and C viruses (HBV, HCV) or human immunodeficiency virus (HIV) infection and estimate the effect of preventive strategies in reducing this risk. A multicentric prospective survey, based on self-administered questionnaires, was conducted during a period of 6 months in 39 Italian hospitals. An accidental exposure to blood or body fluids occurred in 9.2% of 15,375 operations. In about 2% of procedures a parenteral-type injury, such as actual skin puncture or eye contamination, was suffered by the operating surgeon. A needle-stick injury was the commonest accident, and its occurrence was found to vary with the phase of the procedure and its length. The current lifetime risk of acquiring HBV, HCV, and HIV infection in our regions was estimated to be as high as 42.7%, 34.8%, and 0.54%, respectively. The adoption of preventive strategies is expected to reduce this risk to 21% for HBV, 16.6% for HCV, and 0.23% for HIV infection. Active immunization of surgeons against HBV is strongly recommended. The case is also made for the use of a face-shield combined with a permanent change in our surgical practice capable of reducing the current high rate of parenteral injuries. 相似文献
15.
M Longobardi A Bargagna E Mariani P Schenone S Vitagliano L Stella A Di Sarno E Marmo 《Il Farmaco; edizione pratica》1990,45(4):399-404
The synthesis of some N,N-disubstituted 4-amino-5,6-dihydro-3-phenyl-2H-[1]benzothiepino [5,4-b]pyran-2-ones by reaction of phenylchloroketene with a series of N,N-disubstituted (E)-4-aminomethylene-3,4-dihydro-1-benzothiepin-5(2H)-ones, followed by dehydrochlorination of the primary adducts with DBN, is described. The 4-methylphenylamino derivative showed a local anesthetic activity in mice superior to that of lidocaine and the 4-morpholino derivative showed an antiarrhythmic activity in rats comparable to that of quinidine. 相似文献
16.
Alexandros Kolokotronis Evanda Avramidou Thomas Zaraboukas Kalliopi Mandraveli Stella Alexiou Demetrios Antoniades 《Journal of oral pathology & medicine》2006,35(2):123-125
BACKGROUND: The use of immunosuppressive medication is a dominant risk factor for infection in patients with rheumatoid arthritis (RA). Methotrexate (MTX) is one of the traditional disease-modifying antirheumatic drugs. Adalimumab [a human anti-tumor necrosis factor-alpha (anti-TNF-alpha) monoclonal antibody] represent an important advance in the treatment of RA and has been recently come in use. TNF-alpha plays a role in the host defense against Mycobacterium tuberculosis and notably in granuloma formation. Infections occur at a high rate among those who use one or the combination of the two medications. METHOD: We examined a female patient that was referred to our department for evaluation and treatment of a granular lesion on the soft palate and uvula, complaining of mild dysphagia. The patient was treated for 4 months with MTX and adalimumab for RA before the oral lesion appeared. RESULTS: The histopathological examination of a specimen of the oral lesion, taken by biopsy, showed a chronic inflammation characterized by tuberculous granulomas. Polymerase chain reaction test and culture of a new specimen was positive for M. tuberculosis. CONCLUSIONS: The therapeutic use of MTX or/and adalimumab for the treatment of RA or few others diseases, can cause oral tuberculosis. 相似文献
17.
The objective of this work was to investigate the chemistry and the structure-stability relationship of enaminones (a class of enamines formed between a primary amine and a 1,3-dicarbonyl compound) and to evaluate their potential usefulness as prodrugs of primary amines. The acid-catalyzed degradation of the enaminones was found to be very sensitive to minor differences in the structure of the 1,3-dicarbonyl compound used to form the enaminone, but relatively insensitive to changes in the amine portion of the enaminones. A correlation was found between the rate of enaminone hydrolysis and the pKa of the 1,3-dicarbonyl compound, suggesting that the rate-controlling step in the hydrolysis of the enaminones was the proton addition to the vinyl carbon of the enaminone. Enaminones formed with cyclic 1,3-dicarbonyl compounds were significantly more stable than those formed with structurally similar acyclic compounds. Based on chemical stability considerations alone, enaminones do not appear to be good candidates as prodrugs of primary amines. Evidence is presented, however, that enaminones formed between amines and 1,3-ketoesters or lactones may be subject to enzyme-catalyzed degradation. Further research on the design of enaminones destabilized by a triggering enzymatic event that results in the loss of conjugation (e.g., ester or lactone hydrolysis or an oxidation/reduction event) may prove worth pursuing. 相似文献
18.
Success rate and duration of orthodontic treatment for adult patients with palatally impacted maxillary canines. 总被引:2,自引:0,他引:2
Adrian Becker Stella Chaushu 《American journal of orthodontics and dentofacial orthopedics》2003,124(5):509-514
This study was undertaken to examine the success rate and the length of orthodontic treatment of impacted maxillary canines in adult patients. A sample of 19 adults (mean age, 28.8 +/- 8.6 years; range, 20-47 years), who had been treated for a total of 23 impacted maxillary canines, was compared with a younger control group (mean age, 13.7 +/- 1.3 years; range, 12-16 years). The control subjects were chosen for a similar degree of impaction difficulty by carefully matching the positions of the impacted canines in the 3 planes of space. The success rate among the adults was 69.5% compared with 100% among the younger controls. The lower success rate was due to 5 canines that had failed to erupt and 2 canines that had been partially extruded but could not be aligned in the arch. The duration of treating the overall malocclusion of the adults and young subjects did not materially differ. However, the adults showed significant increases in the duration and number of treatment visits required for resolving the canine impaction, in both the simpler and the more difficult cases. When further divided by age, all the failed canines were found in the older (over 30) adult subgroup. It was concluded that the prognosis for successful orthodontic resolution of an impacted canine in an adult is lower than that in a younger patient and that the prognosis worsens with age. Furthermore, when such treatment is undertaken, its successful completion should be expected to take considerably longer. 相似文献
19.
Agenesis of common carotid artery is rare and no report of stenting procedures (carotid artery stenting) for associated stenosis of the internal carotid have been published. We report a case of internal carotid stenosis associated with this anomaly. A 73-year-old male with left internal carotid artery originating from the arch, with significant stenosis, was referred to us. Wallstent was deployed with success. Carotid artery stenting should be reserved to uncomplicated arch anatomy and plaques with low fragmentation risk. 相似文献
20.