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61.
Remote intrapulmonary spread of recurrent respiratory papillomatosis with malignant transformation 总被引:4,自引:0,他引:4
Katz SL Das P Ngan BY Manson D Pappo AS Sweezey NB Solomon MP 《Pediatric pulmonology》2005,39(2):185-188
Recurrent respiratory papillomatosis is the most common neoplasm of the larynx in childhood. Extension into lung parenchyma occurs in less than 1% of patients and has a low risk of malignant transformation. Treatment options for intrapulmonary spread have shown limited success. We describe a case of recurrent respiratory papillomatosis with extensive parenchymal involvement and adenosquamous carcinoma in a 14-year-old girl. 相似文献
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Describing the relationship between magnitude of response, probability of response, dose and time is difficult using traditional two‐dimensional dose–response curves. We devised a novel way of presentation in four dimensions. Data from a previous study of epidural bupivacaine and ropivacaine given for labour analgesia were re‐analysed. For a range of response magnitudes (5–95% reduction in pain score), estimates of doses associated with probabilities of response 0.05–0.95 were calculated using probit analysis. Three dimensional surface plots were constructed with axes x = magnitude of response, y = probability of response and z = log(dose) at intervals for 30 min. Arithmetic interpolation was used to assemble an animation depicting temporal changes in relationship between variables (fourth dimension). Response–probability–dose curves in three and four dimensions were constructed and presented for both drugs. We believe that this model is more aligned with the logic of clinical dose selection compared with traditional two‐dimensional curves. 相似文献
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Monika Janda Val Gebski Alison Brand Russel Hogg Thomas W Jobling Russel Land Tom Manolitsas Anthony McCartney Marcelo Nascimento Deborah Neesham James L Nicklin Martin K Oehler Geoff Otton Lewis Perrin Stuart Salfinger Ian Hammond Yee Leung Tom Walsh Peter Sykes Hextan Ngan Andreas Obermair 《The lancet oncology》2010,11(8):772-780
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H.Y.S. Ngan G.T.S. Cheng D. Cheng L.C. Wong & H.K. Ma 《International journal of gynecological cancer》1996,6(2):115-119
Serum squamous cell carcinoma antigen (SCC) was raised in 62% of 308 patients with squamous cell carcinoma of the cervix before treatment. Post-treatment SCC levels were raised in 69 patients (22.4%). Retrospective review showed that persistently raised SCC level after treatment was significantly associated with persistent or recurrent disease in squamous cell carcinoma of the cervix. The specificity of persistently raised SCC level in association with recurrent disease was 98.2%. The sensitivity in association with recurrent disease was 74.7%. The positive predictive values was 94.2%. The median lead time for recurrence was 4 months. SCC was raised in 38% of patients with clinical evidence of disease in the vagina. One patient had raised SCC one month prior to clinical detection of vaginal metastasis and was salvaged by an exenterative procedure. SCC was raised in 71–91% of patients with metastatic disease in the lung, lymph nodes or other distant sites. Thus, persistently raised SCC level after treatment of squamous cell carcinoma should alert the clinician to look for recurrent disease especially in distant metastatic sites. Post-treatment raised SCC level was associated with less than 5% 5-year survival rate whereas in patients with normal SCC level, the 5-year survival rate was 87%. 相似文献
66.
Ahmed M. Mahmoud Peter Ngan Richard Crout Osama M. Mukdadi 《Annals of biomedical engineering》2010,38(11):3409-3422
Although medical specialties have recognized the importance of using ultrasonic imaging, dentistry is only beginning to discover its benefit. This has particularly been important in the field of periodontics which studies infections in the gum and bone tissues that surround the teeth. This study investigates the feasibility of using a custom-designed high-frequency ultrasound imaging system to reconstruct high-resolution (<50 μm) three-dimensional (3D) surface images of periodontal defects in human jawbone. The system employs single-element focused ultrasound transducers with center frequencies ranging from 30 to 60 MHz. Continuous acquisition using a 1 GHz data acquisition card is synchronized with a high-precision two-dimensional (2D) positioning system of ±1 μm resolution for acquiring accurate measurements of the mandible, in vitro. Signal and image processing algorithms are applied to reconstruct high-resolution ultrasound images and extract the jawbone surface in each frame. Then, all edges are combined and smoothed in order to render a 3D surface image of the jawbone. In vitro experiments were performed to assess the system performance using mandibles with teeth (dentate) or without (nondentate). The system was able to reconstruct 3D images for the mandible’s outer surface with superior spatial resolution down to 24 μm, and to perform the whole scanning in <30 s. Major anatomical landmarks on the images were confirmed with the anatomical structures on the mandibles. All the anatomical landmarks were detected and fully described as 3D images using this novel ultrasound imaging technique, whereas the 2D X-ray radiographic images suffered from poor contrast. These results indicate the great potential of utilizing high-resolution ultrasound as a noninvasive, nonionizing imaging technique for the early diagnosis of the more severe form of periodontal disease. 相似文献
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ABSTRACT: BACKGROUND: AMP-activated protein kinase (AMPK) has recently been considered as a potential target for cancer therapy. However, the expression status of various subunits of the heterotrimeric AMPK in human cancers is rarely reported. We decided to determine their expressions in ovarian carcinomas and their relationships with the disease. METHODS: Expressions and locations of the AMPK-alpha1, -alpha2, -beta1, -beta2, -gamma1 and -gamma2 were detected by quantitative PCR (Q-PCR) and immunohistochemical staining (IHC). Their expression levels in ovarian tumors were compared with normal controls and also correlated with clinicopathological parameters. RESULTS: Except AMPK-alpha1, expressions of the other five AMPK subunits are significantly higher in ovarian carcinomas as determined by Q-PCR. Although IHC detection of AMPK-gamma1 and -gamma2 were not successful, over-expressions of AMPK-alpha2, -beta1, and -beta2 were further confirmed by IHC. Over-expressions of various AMPK subunits occurred independently and were mainly detected in the cytoplasm. Interestingly, AMPK-alpha2 and -beta1 were also detected in the nucleus and cell membrane, respectively. Clinical correlation analyses indicate that expressions of different AMPK subunits are associated with different subtypes of carcinoma. High expression of AMPK-alpha2 is significantly associated with endometrioid carcinomas. On the other hand, high expressions of AMPK-beta and -gamma subunits are associated with mucinous and serous carcinomas, respectively. Furthermore, high expressions of AMPK-beta1 and -gamma2 are also associated with early and late stages of disease, respectively. Finally, patients with high expression of AMPK-alpha2 had better prognosis. CONCLUSIONS: Aberrant expressions of AMPK subunits may play important roles in ovarian carcinogenesis. Each AMPK subunit may have its own function other than just a component of the AMPK molecule. Correlations with clinical parameters suggest that expressions of AMPK subunits have different clinical implications in ovarian cancer development. 相似文献
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