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81.
82.
PURPOSE: Early identification of esophageal cancer patients who are responding or resistant to combined chemoradiotherapy may lead to individualized therapeutic approaches and improved clinical outcomes. We assessed the ability of 3'-deoxy-3'-(18)F-fluorothymidine positron emission tomography (FLT-PET) to detect early changes in tumor proliferation after chemoradiotherapy in experimental models of esophageal carcinoma. EXPERIMENTAL DESIGN: The in vitro and ex vivo tumor uptake of [(3)H]FLT in SEG-1 human esophageal adenocarcinoma cells were studied at various early time points after docetaxel plus irradiation and validated with conventional assessments of cellular proliferation [thymidine (Thd) and Ki-67] and [(18)F]FLT micro-PET imaging. Imaging-histologic correlation was determined by comparing spatial Ki-67 and [(18)F]FLT distribution in autoradiographs. Comparison with fluorodeoxyglucose (FDG) was done in all experiments. RESULTS: In vitro [(3)H]FLT and [(3)H]Thd uptake rapidly decreased in SEG-1 cells 24 hours after docetaxel with a maximal reduction of over 5-fold (P = 0.005). The [(3)H]FLT tumor-to-muscle uptake ratio in xenografts declined by 75% compared with baseline (P < 0.005) by 2 days after chemoradiotherapy, despite the lack of change in tumor size. In contrast, the decline of [(3)H]FDG uptake was gradual and less pronounced. Tumor uptake of [(3)H]FLT was more closely correlated with Ki-67 expression (r = 0.89, P < 0.001) than was [(3)H]FDG (r = 0.39, P = 0.08). Micro-PET images depicted similar trends in reduction of [(18)F]FLT and [(18)F]FDG tumor uptake. Autoradiographs displayed spatial correlations between [(18)F]FLT uptake and histologic Ki-67 distribution in preliminary studies. CONCLUSIONS: FLT-PET is suitable and more specific than FDG-PET for depicting early reductions in tumor proliferation that precede tumor size changes after chemoradiotherapy.  相似文献   
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84.
This is a comparative study of conventional surgery (knife/electric knife) and CO2 laser surgery and their effect on the outcome of stage III (including muscle) and stage IV (including bone) decubitus ulcers with an average area of 400 cm2. It is a prospective clinical study done with two groups of patients of similar age, economic and social background, as well with similar types of decubitus ulcers. Thirty patients were studied in each group. The study demonstrated a statistically significant difference in favor of the patients treated with CO2 laser with regard to operative blood loss, 0.5 cc/cm2 or 20% (P less than .01), infection rate (chi 2 test, P less than .01), and difference (60%) in recovery time (P less than .01). This translated into an average saving of 23 hospitalization days per patient. It also showed a difference, though not statistically significant, favoring the group treated with laser with respect to survival and full recovery. This probably is attributable to the lowered blood loss and infection rate as well as improved operative time and analgesia.  相似文献   
85.
Noninvasive imaging in lung metastatic tumor models is used infrequently because of technical limitations in detecting metastases. We have previously used 2'-fluoro-2'-deoxy-5-iodo-1-beta-d-arabinofuranosyluracil labeled with (131)I ((131)I-FIAU) and demonstrated the applicability of noninvasive imaging for monitoring cancer gene therapy in an experimental animal model of herpes simplex virus type 1 thymidine kinase (HSV1-tk)-expressing tumor xenografts. We have now used the same animal model to effectively and noninvasively monitor the location, magnitude, and duration of therapeutic gene expression over time for the lung metastases model. METHODS: To improve the detectability of lung metastases, an experimental blood-borne lung metastases model in mice was established using intravenously administered HSV1-tk-expressing NG4TL4 fibrosarcoma cells (NG4TL4-TK) and simulated the clinical application of HSV1-tk plus ganciclovir (GCV) prodrug activation gene therapy. The efficacy of noninvasively monitoring the sites of development of lung metastatic lesions and their GCV-induced regression were assessed by SPECT with (131)I-FIAU. RESULTS: The results of this study showed that the lung metastases model of NG4TL4-TK cells could be successfully detected as early as 24 h after intravenous injection of tumor cells radiolabeled with (131)I-FIAU and also subsequently detected by extended monitoring with the intravenous injection of (131)I-FIAU on day 10. In mice treated with GCV, gamma-camera imaging demonstrated a significant growth inhibition of NG4TL4-TK cells of primary tumors and lung metastases on day 7 after initiating treatment. CONCLUSION: We conclude that this in vivo imaging approach will be useful for future studies of the lung metastases model and for the assessment of novel anticancer and antimetastatic therapies.  相似文献   
86.
Leiomyosarcoma of the rectum: diagnostic criteria and surgical approach   总被引:1,自引:0,他引:1  
A case of leiomyosarcoma of the rectum is reported. There was difficulty in establishing the correct histologic diagnosis. Diagnostic criteria, including electron microscopy examination, are reviewed. Abdominoperineal resection of the rectosigmoid is the common therapeutic procedure recommended.  相似文献   
87.
Summary Dogs serve as the vectors of serious parasitic diseases with a zoonotic character. In a one-year-study, we collected and examined 752 faeces of dogs. In these faecal samples, 11 different species of intestinal endoparasites were detected, as follows: Toxocara spp. eggs (21.9 %), eggs from the family Ancylostomatidae (18.4 %), coccidia oocysts (10.4 %), eggs of Trichuris spp. (10.0 %), Toxascaris leonina (7.3 %), Capillaria spp. (5.9 %), Taenia type eggs (3.2 %) and Giardia spp. cysts (1.6 %). Echinococcus multilocularis was detected in one sample. Toxocara spp. eggs were dominant in all dog categories, but in hunting dogs they occurred at the highest rate (45.1 %). Faecal samples of dogs from rural ecosystems showed 66.0 % prevalence of intestinal helminths. Presence of Toxocara spp. eggs was found in 25.0 % of sand samples.  相似文献   
88.
89.
A 45-year-old male was admitted to the hospital because of polyuria and polydipsia. After admission, proteinuria and hematuria were found. The kidney function deteriorated and necessitated the initiation of chronic hemodialysis. Examination of the bone marrow revealed multiple myeloma and kappa light chains were found in the urine. The kidney biopsy showed membranoproliferative glomerulonephritis with dense deposits in the glomerular basement membrane.  相似文献   
90.
BACKGROUND: Nuclear medicine imaging is increasingly used in the evaluation of tumors of the head and neck. In the current study, we assess the value of single-photon emission tomography (SPECT) using the amino acid tracer L-3-[123I]iodine-alpha-methyl-tyrosine (IMT) for the detection of recurrent head and neck cancer. PATIENTS AND METHODS: 45 consecutive patients with suspected recurrence of previously treated head and neck cancer were examined by IMT-SPECT using a dual head system with integrated low-dose computed tomography (CT). The accuracy of the IMT-SPECT was evaluated by correlating the findings with results of histology or clinical and CT/MRI (magnetic resonance imaging) follow-up examinations. RESULTS: The sensitivity, specificity and accuracy of IMT-SPECT in the detection of recurrent/persistent tumors were 83, 89 and 84.5%, respectively. The positive and negative predictive value amounted to 96.5 and 60%, respectively. CONCLUSION: IMT-SPECT using integrated low-dose CT appears to be a helpful complementary imaging tool for the detection of local recurrences and lymph node metastases of head and neck cancer and their differentiation from treatment-induced changes. The advantage of the method is the high positive predictive value in the diagnosis of relapsed tumors. However, a negative IMT-SPECT result does not exclude a recurrence.  相似文献   
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