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41.
The "High-Riding" superior pericardial recess: CT findings   总被引:3,自引:0,他引:3  
OBJECTIVE. We recently observed patients in whom the superior pericardial recess extended cephalad ("high-riding") into the right paratracheal region. In these patients, differentiation from mediastinal lymphadenopathy or mass was difficult. The purpose of this study was to assess the prevalence and CT features of the high-riding superior pericardial recess. CONCLUSION. Narrow-collimation CT with multiplanar reformations was useful for confidently diagnosing a high-riding superior pericardial recess and for distinguishing it from pathologic lesions.  相似文献   
42.
Spinal intradural capillary hemangioma: MR findings   总被引:6,自引:0,他引:6  
We report a case of a spinal intradural capillary hemangioma. On MR images, a well-circumscribed intradural mass was detected at the T8-T9 level. The signal intensity of the mass relative to the spinal cord was isointense on T1-weighted images, hyperintense on T2-weighted images, and showed homogeneous, strong enhancement on contrast-enhanced T1-weighted images. The mass had both extramedullary and intramedullary components.  相似文献   
43.
BACKGROUND: The time for femoral lengthening is shortened if external fixation is combined with intramedullary nailing. However, several complications have been reported with this procedure. PATIENTS AND METHODS: We retrospectively reviewed the outcome of femoral lengthening performed over an intramedullary nail using external fixation in 22 patients. These patients were followed for a mean of 3.2 (2-5.2) years. The mean age was 22 (13-35) years at the time of the index procedure. The mean lengthening was 5 (2.7-8.1) cm and the external fixator was removed after median 20 (8-30) weeks. The mean external fixation index was 24 (11-35) days/cm and the mean consolidation index was 43 (26-55) days/cm of lengthening. RESULTS: 3 patients who had a past history of infection or open trauma developed osteomyelitis which required removal of the nail. There were 4 knee joint complications when the lengthening was over 20%, including posterior knee subluxation and patella subluxation. In 1 patient, the lengthened segment collapsed with breakage of locking screws. INTERPRETATION: Although lengthening over a nail can reduce the duration of external fixation, caution is required to prevent major complications.  相似文献   
44.
Korean ginseng and mountain ginseng (Panax ginseng CA Meyer) are important traditional herbal plants whose ginsenosides are generally accepted as serving to improve sexual functions, such as penile erection. We investigated the effects of tissue-cultured mountain ginseng extract (TMGE) on male patients with erectile dysfunction (ED). A double-blind, placebo-controlled study was conducted with 143 patients experiencing ED. Over the course of 8 weeks, one group took 1 000 mg of TMGE twice a day, and the other group took 1 000 mg of placebo twice a day. The effects of the TMGE and the placebo were analyzed using the Korean version of the International Index of Erectile Function (IIEF) questionnaire. A total of 86 patients completed 8 weeks of treatment. The scores on the five domains of the IIEF after medication were significantly higher than the baseline scores in the group treated with TMGE (P 〈 0.05), whereas no significant improvement was observed in the placebo group (P 〉 0.05). Erectile function and overall satisfaction scores after medication were significantly higher in the TMGE group than in the placebo group (P 〈 0.05). Erectile function of patients in the TMGE-treated group significantly improved, suggesting that TMGE could be utilized for improving erectile function in male patients.  相似文献   
45.
PurposeTo evaluate the effectiveness, safety, and complications of uterine artery embolization (UAE) in women with large fibroid tumors.Materials and MethodsFrom January 2005 to February 2011, 323 patients underwent UAE for symptomatic uterine leiomyomas without adenomyosis and were included in this study. Patients were divided into two groups: those with a large tumor burden (group 1; n = 63), defined as a dominant tumor with a longest axis of at least 10 cm or a uterine volume of at least 700 cm3; and the control group (group 2; n = 260). Tumor infarction and volume reduction were calculated based on magnetic resonance imaging findings. Symptom status was assessed with a visual analog scale. Postprocedure complications and repeat interventions were recorded. The data were analyzed with appropriate statistical tests.ResultsNo significant differences were seen between the two groups in volume reduction of dominant tumors (46.5% in group 1 vs 52.0% in group 2; P = .082) or percentage volume reduction of the uterus (40.7% in group 1 vs 36.3% in group 2; P = .114). Also, no significant differences were seen between the two groups regarding satisfaction scores at immediate or midterm follow-up (P = .524 and P = .497) or in the presence of procedure-related complications (P = .193).ConclusionsUAE outcomes in large fibroid tumors were comparable to those in smaller tumors, without an increased risk of significant complications. Tumor size may not be a key factor in predicting successful outcomes of UAE.  相似文献   
46.
Background We assessed whether new parameter that considers both tumor volume change and necrosis rate predicts metastasis-free survival of localized osteosarcoma patients. We also evaluated relationship between tumor volume change and necrosis rate or metastasis-free survival. Methods We retrospectively reviewed 151 patients with stage II osteosarcoma who were treated with surgery and neoadjuvant chemotherapy. The tumor volume change was measured and calculated based on pre- and postchemotherapy magnetic resonance images. The mean metastasis-free interval was 83.1 months. We calculated adjusted tumor necrosis rate as following formula: 100–(100–necrosis rate) × postchemotherapy/prechemotherapy tumor volume. Survival and logistic regression analyses were used to evaluate the correlation among size parameters, tumor necrosis rate and survival. Results The 5-year metastasis-free survival rate of 151 patients was 71.4% (95% CI, 67.7–75.1%). American Joint Committee on Cancer (AJCC) stage IIB (RR 2.27; 95% CI, 1.11–4.62; P = 0.025) and poor adjusted tumor necrosis rate (RR 2.02; 95% CI, 1.05–3.89; P = 0.035) independently correlated with metastasis-free survival period. Further, tumor volume change independently correlated with necrosis rate. Decreased tumor volume could predict good response, with sensitivity of 80.2%, specificity of 68.6%, and positive predictive value (PPV) of 74.7%. Increased or stable tumor volume could predict poor response, with sensitivity of 68.6%, specificity of 80.2%, and PPV of 75.0 %. Conclusion The necrosis rate adjusted by the tumor volume change is an independent prognostic factor in osteosarcoma. This adjusted tumor necrosis rate may serve as a basis for risk-adapted therapy in combination with other prognostic factors.  相似文献   
47.
SUMMARY: Peritonitis and exit‐site infections remain the most important limitations to the delivery of continuous ambulatory peritoneal dialysis (CAPD). Contamination of the peritoneum, from endogenous or exogenous sources, is responsible for most peritonitis episodes. Patients usually present with a cloudy bag, although other causes should be distinguished. Clinical suspicion of peritonitis should be followed rapidly by microbiological examination and empirical treatment. Microbiological confirmation allows for subsequent treatment based on sensitivities. Other interventions such as catheter removal may be appropriate in some patients. Exit‐site infections should also be identified and treated early. Peritonitis may be further prevented by adequate exit‐site care, hygienic methods, and techniques to minimise early contamination of the exit site. Mupirocin may also have a role in preventing infections caused by Staphylococcus aureus.  相似文献   
48.
SUMMARY: The continuous replacement of renal function must facilitate fluid and solute homeostasis, nutrition and vital organ function, and, where possible, hasten the recovery of renal function. Difficulties with anticoagulation, biocompatibility, mobility and cost remain obstacles to be overcome. the use of continuous renal replacement therapy (CRRT) to remove systemic inflammatory mediators is yet to be confirmed. Although survival benefits of CRRT over intermittent dialysis remain controversial, the slow continuous removal of fluid, acid and solute has a number of advantages, especially where patients are haemodynamically unstable.  相似文献   
49.
BACKGROUND AND OBJECTIVES: This study examined the effect of lumbar flexion on the extent of the epidural block during lumbar epidural anesthesia. METHODS: The epidural catheter was introduced at the L3-4 interspace with the patient in the lateral decubitus position with the surgical side down. After administering a test drug (3 mL of 2% lidocaine and 15 mug of epinephrine), the patients were randomly allocated to 1 of 2 groups: Group F (n = 16, lumbar spine flexed) and Group N (n = 17, lumbar spine in the neutral position). In both groups, 2% lidocaine (16 mL) mixed with sodium bicarbonate (2 mL) was administered through the epidural catheter while the patient maintained the lateral decubitus position with the lumbar spine either flexed or in the neutral position. All the patients maintained their respective positions for 5 minutes and were subsequently turned to the supine position. The pinprick block level and the degree of motor blockade were assessed every 10 minutes for 60 minutes after administering the local anesthetics. A 2-dermatomal difference in uppermost block between groups was determined to be clinically significant. RESULTS: The median difference between groups in the uppermost pinprick block level was only 1.5 dermatomes and it did not satisfy our criteria for clinical significance. There were no significant differences between the 2 groups in the lowermost pinprick block level and the degree of motor block. CONCLUSIONS: Lumbar flexion has no clinically relevant effect on sensory spread during epidural anesthesia.  相似文献   
50.
Jeon DH  Oh K  Oh BC  Nam DH  Kim CH  Park HB  Cho J  Lee JR  Lee DS  Lee G 《Xenotransplantation》2007,14(3):236-242
BACKGROUND: Effective intervention achieved by manipulating cell-mediated xenogeneic immune responses would critically increase the clinical feasibility of xenotransplantation as immediate hyperacute rejections become controllable through genetic modulations of donor organs. Endogenous negative regulatory signals like the programmed death 1 (PD-1)-programmed death ligand 1 (PD-L1) system are candidate targets for the control of cell-mediated xenogeneic immune response. METHODS: A porcine PD-L1 molecule was cloned using RACE (rapid amplification of cDNA ends) technology based on the human PD-L1 sequence. The functional effects of cloned porcine PD-L1 were tested on human CD4(+) T cell activation using porcine PD-L1-transfected bystander cells. Cellular proliferation was monitored by [3H] thymidine incorporation, and human T cell apoptosis was measured by flow cytometry. RESULTS: Porcine PD-L1 (GenBank accession number AY837780) was found to have 73.8% sequence homology with human PD-L1 and to contain two immunoglobulin domains in its extracellular region. Moreover, porcine PD-L1 expressed on Chinese hamster ovary (CHO) cells inhibited human CD4(+) T cell proliferation stimulated with anti-CD3 only or anti-CD3 plus anti-CD28. Percentages of apoptotic activated human T cells increased by over 30% in the presence of porcine PD-L1/CHO cells, and the addition of recombinant human PD-1-Fc fusion proteins during human T cell activation reversed the inhibitory effects of porcine PD-L1. CONCLUSIONS: Cloned porcine PD-L1 showed high sequence homology with human PD-L1 and a similar molecular structure. Moreover, porcine PD-L1 inhibited human CD4(+) T cell activation in human PD-1-dependent manner, and this involved activated T cell apoptosis. The authors suggest that PD-1-PD-L1 might play an important endogenous immune regulatory role during xenogeneic transplantation, and that the effective application of this system would improve transplanted xenogeneic organ survival.  相似文献   
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