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51.
Microbial keratitis following lamellar keratoplasty   总被引:2,自引:0,他引:2  
OBJECTIVE: To determine the predisposing factors, etiologic agents, and clinical and visual outcomes in infectious keratitis following lamellar keratoplasty (LK). METHODS: One hundred thirty-five eyes (135 patients) that had undergone LK were retrospectively analyzed for the occurrence of infectious keratitis following LK. The parameters evaluated were predisposing factors, seasonal variation, indications and type of LK, time interval between LK and infection, site and depth of infection, etiologic organisms, type of treatment, outcome in terms of graft status, secondary surgery, visual acuity, and the donor tissue profile. RESULTS: The incidence of infectious keratitis following LK was 11.11%. The most significant predisposing factor was persistent epithelial defect (3 eyes) and suture abscesses (3 eyes). Most cases occurred between May and August (9/15). Twelve cases developed infection within 2 weeks of surgery (80%). Seven cases (7/15) occurred with onlay grafts, 6 with inlay grafts, and 2 with large-diameter LK. Cultures of corneal scrapings were positive in 11 eyes (73.3%), and the most common isolated organism was coagulase-negative Staphylococcus (CNS). Only 2 eyes responded to medical therapy, and graft sloughing occurred in 9 cases. Six eyes underwent penetrating keratoplasty to either salvage the integrity of globe or for visual rehabilitation of cases where infection resulted in corneal opacity. CONCLUSIONS: Infections after LK may not be amenable to antimicrobial therapy and may necessitate the removal of the graft or a therapeutic penetrating keratoplasty.  相似文献   
52.
A case of thymic carcinoma with rhabdoid differentiation is presented. A 67-year-old man who presented with chest pain and hemoptysis was referred to The University of Texas M. D. Anderson Cancer Center (Houston, TX). Radiologic studies revealed a large anterior mediastinal mass. After the initial biopsy and preoperative chemotherapy, a radical thymectomy revealed a stage III thymic carcinoma with a rhabdoid component. The rhabdoid component was characterized by large cells with an eccentric nucleus, prominent nucleolus, and typical paranuclear cytoplasmic inclusions. Immunohistochemical and electron microscopic studies confirmed the presence of rhabdoid cells with the paranuclear cytoplasmic inclusions staining for both pancytokeratin and vimentin. The patient was given postoperative chemotherapy and radiation. He has since developed metastases to the pelvis and is alive with disease at 20 months of follow-up. To our knowledge, this is the first reported case of thymic carcinoma with rhabdoid features.  相似文献   
53.
Purpose:To quantitatively correlate the loss of stereopsis by induced anisometropia with its effect on tasks that require binocular vision and stereopsis, such as ophthalmic surgery in a simulated environment.Methods:Thirty-nine ophthalmic residents with best-corrected visual acuity of 20/20 or better OU, with normal binocular vision and stereopsis, were recruited for the study. Anisometropia was induced using spherical and cylindrical trial lenses from +1D to +5D in a trial frame. The residents performed an anterior chamber navigation exercise on the EYESi simulator and the surgical score at baseline and for each level of induced anisometropia was noted. Near stereopsis was assessed by the Randot test and TNO test at baseline and for each level of induced anisometropia.Results:Stereoacuity on the Randot test and TNO test were 30 (95% CI, 25.9–34.1) and 44.4 (95% CI, 28.5–60.3) arcseconds, respectively which reduced to 65.5 (95% CI, 48.7–82.3) and 75.9 (95% CI, 15.5–136.3) arcseconds at anisometropia of +1D Sph (P < 0.001) and 380 (95% CI, 309.9–450.1) and 1922.1 (95% CI, 1582.5–2261.7) arcseconds for +5D Sph, respectively for the two tests, (P < 0.001). The corresponding surgical score reduced from 93.8 (95% CI, 91.1–96.7) to 87.5 (95% CI, 79.2–95.8, P < 0.001) for 1 DSph and 55.97 (95% CI, 38.3–73.7, P < 0.001) for 5DSph. There was a strong negative correlation between stereopsis scores and surgical task scores (Spearman''s rho -0.86, P value <0.001) Similar changes were seen for anisometropia induced with cylindrical powers.Conclusion:Induced anisometropia is associated with a significant diminution in surgical task scores in a simulated environment and this is correlated with the deterioration in stereoacuity. Assessment of stereopsis may be included as a regular part of the screening procedure for ophthalmic trainee residents.  相似文献   
54.
To determine utility of luteinizing hormone (LH) estimation, post intramuscular (IM) depot leuprolide in comparison with subcutaneous leuprolide stimulation test. Test for monitoring therapy in patients with gonadotropin dependent precocious puberty (GDPP). In seven patients of GDPP, who were treated with 11.25 mg depot leuprolide, the LH peak after subcutaneous (sc) test was compared with LH at hourly interval for 4 h after IM depot leuprolide for 13 tests and 3rd hour value for next ten tests. These two values were compared both before and after therapy. Before therapy, the mean ± SD LH peak after subcutaneous leuprolide stimulation test was 20.6 ± 7.85 IU/l (range 9.64–30.4 IU/l), and it was 27.3 ± 12.21 IU/l 3 h after the first depot leuprolide injection (range 10.5–45.4 IU/l). During therapy, the mean ± SD of LH peak after sc stimulation test was 1.96 ± 0.75 IU/l (range 1.1–3.1 IU/l), and it was 2.58 ± 0.54 IU/l (range 1.4–3.4 IU/l) 3 h after depot leuprolide injection. Three-hour LH value following IM depot leuprolide injection (11.25 mg) can be used for monitoring therapy in patients with GDPP because of its convenience and cost effectiveness.  相似文献   
55.
Spontaneous left atrial intramural haematoma is rare. We got one such case which gave rise to cardiac tamponade. This presentation is to increase awareness about its evaluation and management.  相似文献   
56.

Background

Conventional bright blood late gadolinium enhancement (bright blood LGE) imaging is a routine cardiovascular magnetic resonance (CMR) technique offering excellent contrast between areas of LGE and normal myocardium. However, contrast between LGE and blood is frequently poor. Dark blood LGE (DB LGE) employs an inversion recovery T2 preparation to suppress the blood pool, thereby increasing the contrast between the endocardium and blood. The objective of this study is to compare the diagnostic utility of a novel DB phase sensitive inversion recovery (PSIR) LGE CMR sequence to standard bright blood PSIR LGE.

Methods

One hundred seventy-two patients referred for clinical CMR were scanned. A full left ventricle short axis stack was performed using both techniques, varying which was performed first in a 1:1 ratio. Two experienced observers analyzed all bright blood LGE and DB LGE stacks, which were randomized and anonymized. A scoring system was devised to quantify the presence and extent of gadolinium enhancement and the confidence with which the diagnosis could be made.

Results

A total of 2752 LV segments were analyzed. There was very good inter-observer correlation for quantifying LGE. DB LGE analysis found 41.5% more segments that exhibited hyperenhancement in comparison to bright blood LGE (248/2752 segments (9.0%) positive for LGE with bright blood; 351/2752 segments (12.8%) positive for LGE with DB; p?<?0.05). DB LGE also allowed observers to be more confident when diagnosing LGE (bright blood LGE high confidence in 154/248 regions (62.1%); DB LGE in 275/324 (84.9%) regions (p?<?0.05)). Eighteen patients with no bright blood LGE were found to have had DB LGE, 15 of whom had no known history of myocardial infarction.

Conclusions

DB LGE significantly increases LGE detection compared to standard bright blood LGE. It also increases observer confidence, particularly for subendocardial LGE, which may have important clinical implications.
  相似文献   
57.
Biomedical Microdevices - Electrocorticography signals, the intracranial recording of electrical signatures of the brain, are recorded by non-penetrating planar electrode arrays placed on the...  相似文献   
58.
59.
ObjectiveTo investigate the clinical and procedural characteristics in patients with a history of renal transplant (RT) and compare the outcomes with patients without RT in 2 national cohorts of patients undergoing percutaneous coronary intervention (PCI).Patients and MethodsData from the National Inpatient Sample (NIS) and British Cardiovascular Intervention Society (BCIS) were used to compare the clinical and procedural characteristics and outcomes of patients undergoing PCI who had RT with those who did not have RT. The primary outcome of interest was in-hospital mortality.ResultsOf the PCI procedures performed in 2004-2014 (NIS) and 2007-2014 (BCIS), 12,529 of 6,601,526 (0.2%) and 1521 of 512,356 (0.3%), respectively, were undertaken in patients with a history of RT. Patients with RT were younger and had a higher prevalence of congestive cardiac failure, hypertension, and diabetes but similar use of drug-eluting stents, intracoronary imaging, and pressure wire studies compared with patients who did not have RT. In the adjusted analysis, patients with RT had increased odds of in-hospital mortality (NIS: odds ratio [OR], 1.90; 95% CI, 1.41-2.57; BCIS: OR, 1.60; 95% CI, 1.05-2.46) compared with patients who did not have RT but no difference in vascular or bleeding events. Meta-analysis of the 2 data sets suggested an increase in in-hospital mortality (OR, 1.79; 95% CI, 1.40-2.29) but no difference in vascular (OR, 1.24; 95% CI, 0.77-2.00) or bleeding (OR, 1.21; 95% CI, 0.86-1.68) events.ConclusionThis large collaborative analysis of 2 national databases revealed that patients with RT undergoing PCI are younger, have more comorbidities, and have increased mortality risk compared with the general population undergoing PCI.  相似文献   
60.
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