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991.
We analyzed the data for 53 patients with histologically proven primary squamous cell carcinoma of the head and neck treated with radiotherapy between February 2006 and August 2009. All patients underwent contrast-enhanced (CE)-CT and 18F-fluorodeoxyglucose (FDG)-PET before radiation therapy planning (RTP) to define the gross tumor volume (GTV). The PET-based GTV (PET-GTV) for RTP was defined using both CE-CT images and FDG-PET images. The CE-CT tumor volume corresponding to a FDG-PET image was regarded as the PET-GTV. The CE-CT-based GTV (CT-GTV) for RTP was defined using CE-CT images alone. Additionally, CT-GTV delineation and PET-GTV delineation were performed by four radiation oncologists independently in 19 cases. All four oncologists did both methods. Of these, PET-GTV delineation was successfully performed in all 19 cases, but CT-GTV delineation was not performed in 4 cases. In the other 15 cases, the mean CT-GTV was larger than the PET-GTV in 10 cases, and the standard deviation of the CT-GTV was larger than that of the PET-GTV in 10 cases. Sensitivity of PET-GTV for identifying the primary tumor was 96%, but that of CT-GTV was 81% (P < 0.01). In patients with oropharyngeal cancer and tongue cancer, the sensitivity of CT-GTV was 63% and 71%, respectively. When both the primary lesions and the lymph nodes were evaluated for RTP, PET-GTV differed from CT-GTV in 19 cases (36%). These results suggested that FDG-PET is effective for defining GTV in RTP for squamous cell carcinoma of the head and neck, and PET-GTV evaluated by both CE-CT and FDG-PET images is preferable to CT-GTV by CE-CT alone.  相似文献   
992.
CHOP (cyclophosphamide, adriamycin, vincristine, and prednisolone) plus rituximab is a standard chemotherapy used to treat patients with aggressive B-cell non-Hodgkin lymphoma (B-NHL). However, among elderly patients, this regimen has not been completely satisfactory in its efficacy and safety. We report our clinical experience in 8 collaborative institutions to determine if the VNCOP-B (etoposide, mitoxantrone, cyclophosphamide, vincristine, prednisolone, and bleomycin) combination therapy plus rituximab was effective and safe to treat elderly patients with aggressive B-NHL. Between September 2004 and December 2007, 23 previously untreated patients, median age 73 years, 50.0% classified as high-intermediate/high-risk on the standard International Prognostic Index (IPI) entered this trial. Complete remission rate was 90.5%, with a 100% overall response rate (RR) at the end of induction therapy; overall survival (OS) rate at 3 years was 76.4% (median follow-up 744 days), with an 82.6% 3-year progression-free survival (PFS) rate (median follow-up 744 days). The most common grade 3/4 toxicities were hematologic, including neutropenia in 75.0% of the patients despite prophylactic administration of granulocyte colony-stimulating factor (G-CSF), febrile neutropenia in 30.0%, respectively. There was no treatment-related mortality (TRM). Rituximab not only combined with chemotherapy but also given sequentially improved survival. R-VNCOP-B could be another option for elderly patients who are not considered to tolerate in receiving R-CHOP.  相似文献   
993.
The use of surrogate endpoints is expected to play an important role in the development of new drugs, as they can be used to reduce the sample size and/or duration of randomized clinical trials. Biostatistical researchers and practitioners have proposed various surrogacy measures; however, (i) most of these surrogacy measures often fall outside the range [0,1] without any assumptions, (ii) these surrogacy measures do not provide a cut‐off value for judging a surrogacy level of candidate surrogate endpoints, and (iii) most surrogacy measures are highly variable; thus, the confidence intervals are often unacceptably wide. In order to solve problems (i) and (ii), we propose a new surrogacy measure, a proportion of the treatment effect captured by candidate surrogate endpoints (PCS), on the basis of the decomposition of the treatment effect into parts captured and non‐captured by the candidate surrogate endpoints. In order to solve problem (iii), we propose an estimation method based on the half‐range mode method with the bootstrap distribution of the estimated surrogacy measures. Finally, through numerical experiments and two empirical examples, we show that the PCS with the proposed estimation method overcomes these difficulties. The results of this paper contribute to the reliable evaluation of how much of the treatment effect is captured by candidate surrogate endpoints. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
994.
To investigate the relationship between ischemic time and rejection against allotransplants, vascularized cutaneous flaps from the groin of Brown Norway rats were transplanted to Lewis rats. The ischemic time was set at 1 hour and 6 hours for comparison. Cycrosporine A was used as the immunosuppressant. The results showed more severe rejection in the 6 hours ischemic time group in vivo, and in vitro examination using mixed lymphocyte reaction assay also demonstrated a greater antidonor response in 6 hours‐ischemic group than that in 1 hour‐group. Immunohistochemical study demonstrated more MHC class II antigen expression in 6 hours‐ischemic group than in 1 hour‐group. These results suggest that longer ischemic time induces more severe rejection against allo‐transplanted tissue compared with the shorter one through an upregulation of MHC class II antigen. It is expected that these findings contribute to the studies for investigating the mechanism of rejection against the allo‐transplants. © 2010 Wiley‐Liss, Inc. Microsurgery 2010.  相似文献   
995.

Background  

Laparoscopic antireflux surgery is the gold standard for surgical treatment of gastroesophageal reflux disease (GERD), and a well-defined learning curve for the procedure has been described. This study aimed to assess whether the surgeon’s experience has an effect on 1-year symptom scores and patient satisfaction.  相似文献   
996.
MicroRNAs (miRNAs) are small non-coding ribonucleic acids (RNAs) of approximately 22 bp that induce RNA interference with a complementary messenger RNA (mRNA) and act in silencing of mRNA. miRNAs are strongly associated with cancer development and those involved in carcinogenesis are classified into oncogenic miRNAs and tumor suppressor miRNAs (tumor suppressor miRs). Specific miRNAs are expressed in various tissues and changes in regulation of gene expression are thought to cause carcinogenesis. Thus, tissue-specific miRNAs may be biomarkers for cancer diagnosis and prognosis. Approaches to application of miRNAs as cancer therapy are also ongoing, based on the involvement of miRNAs in carcinogenesis. In endometrial cancer, miRNAs are associated with regulation of gene expression, epigenetic dysfunction and carcinogenesis. Thus, miRNAs are likely to have key roles in diagnosis, prognostic prediction, and therapy in endometrial cancer.  相似文献   
997.
998.
We report a case of hemorrhagic cytomegalovirus (CMV) colitis, occurring in a postoperative patient due to a weakened immune system. An 85-year-old woman with a medical history, including chronic renal failure treated with oral administration of prednisolone, underwent colectomy due to an ascending colon cancer. While the postoperative course was favorable, she exhibited acute severe abdominal pain and massive bloody discharge after 11 days of surgery. Her colonoscopic examination showed multiple longitudinal ulcers on the anastomosis. In addition to these endoscopic findings, her past medical history helped suggest CMV colitis. Because serological testing revealed positive CMV antigen, she was finally given a diagnosis of CMV colitis and received intravenous ganciclovir for the initial treatment. Hemorrhagic CMV colitis after colectomy is an important postoperative complication; we therefore present our case with diagnosis and treatment experience.Key words: Cytomegalovirus, Immunocompromised host, Hemorrhagic colitis  相似文献   
999.
Carotid duplex ultrasonography (CDU) is one of the most well-known imaging methods for arteriosclerosis and ischemic stroke. For neurosurgeons, it is very important for the details of carotid plaque to be thoroughly investigated by CDU. Symptomatic carotid plaque is very fragile and easily changes morphologically, and so requires frequent CDU examination. Furthermore, after carotid endarterectomy (CEA) and carotid artery stenting (CAS), restenosis is evaluated with CDU. CDU facilitates not only morphological imaging in the B mode, but also allows a flow study with color Doppler and duplex imaging. So, CDU can help assess the presence of proximal and intracranial artery lesions in spite of only having a cervical view, and the patency of the extracranial artery to intracranial artery bypass is revealed with CDU, which shows a rich velocity and low pulsatility index (PI) in duplex imaging. For the examiner, it is necessary to ponder on what duplex imaging means in examinations, and to summarize all imaging finding.  相似文献   
1000.
This paper compared the specificity of recollections of autobiographical memories where musical cues for events were varied. We used music which was popular in the past as cues which were related to a larger number of past individual events (frequent events cues) and music which was typically only sung at graduation ceremonies as cues which were related to a smaller number of events (rare events cues). In the instructed retrieval condition, participants were told to listen to the music and to recall past events, whereas in incidental retrieval condition, the instruction was only to listen to the music. Then participants were asked to describe what they recalled while hearing the music. When frequent events musical cues were played, the specificities of the recalled events were higher in the instructed retrieval condition than in the incidental retrieval condition. In contrast, when rare events musical cues were played, there were no differences in the specificities of the recalled events.  相似文献   
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