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91.
PURPOSE: To compare the 24-h microtensile bond strength of a microfilled hybrid composite to the same material after mechanical and/or chemical treatment and assess the effect of oxygen inhibition on the composite-composite bond. MATERIALS AND METHODS: Forty composite cylinders of Gradia Direct Anterior (GC) were prepared and stored 24 h prior to the following surface treatments: 50-microm aluminum oxide air abrasion and 37% phosphoric acid etching (group 1); hydrochloric acid and 6.9% hydrofluoric acid etching (group 2); diamond bur roughening and 37% phosphoric acid etching (group 3); diamond bur roughening (group 4). In all groups, Prime & Bond NT (Dentsply De Trey) was applied and light cured in air or under a nitrogen atmosphere, prior to layering a buildup of the repairing resin composite. Microtensile bond strength measurements were performed. Data were statistically analyzed with two-way ANOVA and Tukey's test (alpha = 0.05). RESULTS: The curing atmosphere did not significantly influence the interfacial strength (p < 0.05). Surface treatment significantly affected the composite-composite bond (p > 0.05). Air abrasion, regardless of curing atmosphere, resulted in the strongest bond (p < 0.05). The other treatments were comparable. CONCLUSION: Air abrasion and the application of a bonding agent offer satisfactory bond strengths for composite repair. The oxygen inhibition layer on a light-cured adhesive is not crucial to the success of the 24-h composite-composite bond.  相似文献   
92.
The aim of this study was to evaluate the ability of five experimental resins, which ranged from hydrophobic to hydrophilic blends, to seal acid-etched dentine saturated with water or ethanol. The experimental resins (R1, R2, R3, R4, and R5) were evaluated as neat bonding agents (100% resin) or as solutions solvated with absolute ethanol (70% resin/30% ethanol). Fluid conductance was measured at 20 cm H(2)O hydrostatic pressure after sound dentine surfaces were: (i) covered with a smear layer; (ii) acid-etched; or (iii) bonded with neat or solvated resins, which were applied to acid-etched dentine saturated with water or ethanol. In general, the fluid conductance of resin-bonded dentine was significantly higher than that of smear layer-covered dentine. However, when the most hydrophobic neat resins (R1 and R2) were applied to acid-etched dentine saturated with ethanol, the fluid conductance was as low as that produced by smear layers. The fluid conductance of resin-bonded dentine saturated with ethanol was significantly lower than for resin bonded to water-saturated dentine, except for resin R4. Application of more hydrophobic resins may provide better sealing of acid-etched dentine if the substrate is saturated with ethanol instead of with water.  相似文献   
93.
94.
Successful simultaneous pancreas‐kidney transplantation (SPK) improves quality‐of‐life and prolongs kidney allograft and patient survival in type‐1 diabetic (T1DM) patients. However, the use of SPK in type‐2 diabetic (T2DM) patients remains limited. We examined a national transplant registry for 35 849 T2DM kidney disease patients who received transplant between 2000 and 2016 and survived the first 3 months with a functioning kidney, and categorized as: deceased‐donor kidney transplant alone (DD‐KA, 68%), living‐donor kidney transplant alone (LD‐KA, 30%), or SPK (2%). Among SPK recipients, 6% had pancreas allograft failure within 3 months (SPK,P‐) and 94% had a functional pancreas (SPK,P+). Associations of transplant type with kidney allograft failure and death (multivariable‐adjusted hazard ratio, 95%LCLaHR95%UCL), over follow‐up through December 2018, were quantified by multivariable inverse probability of treatment weighted survival analyses. SPK recipients had better kidney graft and patient survival than LD‐KA or DD‐KA recipients. Compared to SPK,P+, DD‐KA, or LD‐KA recipients had significantly higher risk of kidney allograft failure (DD‐KA: aHR 1.532.203.17; LD‐KA: aHR 1.291.872.71) and death (DD‐KA: aHR 2.123.255.00; LD‐KA: aHR 1.542.353.59). SPK,P‐ recipients had significantly higher risk of death (aHR 1.683.306.50). Similar to T1DM, T2DM patients with SPK have a survival benefit compared to those with kidney transplant alone, but this benefit depends upon successful early pancreas function.  相似文献   
95.

Objective

To assess the effect of neoadjuvant targeted molecular therapies (TMTs) on size and level of inferior vena cava tumor thrombi and to evaluate their impact on surgical management.

Methods

We retrospectively analyzed the data of 14 patients treated for a clear cell renal cell carcinoma with inferior vena cava thrombi by neoadjuvant TMT before nephrectomy. Clinical, pathological and perioperative data were gathered retrospectively at each institution. The primitive tumor size and the thrombus size were defined by computed tomography before TMT. The tumor thrombus level was defined according to the Novick’s classification.

Results

Before TMT, thrombus level was staged I for 1 (7 %), II for 10 (72 %) and III (21 %) for 3 patients. First-line therapy was sunitinib in 11 cases and sorafenib in 3 cases. Median therapy duration was two cycles (1–5). Three patients experienced major adverse effects (grade III) during TMT. Following TMT, 6 (43 %) patients had a measurable decrease, 6 (43 %) had no change, and 2 (14 %) had an increase in the thrombus. One patient (7 %) had a downstage of thrombus level, 12 (85 %) had stable thrombi, and 1 (7 %) had an upstage. Regarding primary tumor, 7 (50 %), 5 (36 %) and 2 (14 %) patients had a decrease, stabilization and an increase in tumor size, respectively.

Conclusion

Neoadjuvant TMT appears to have limited effects on renal tumor thrombi. This retrospective study failed to demonstrate a significant impact of neoadjuvant TMT on surgical management of clear cell renal cell carcinoma with inferior vena cava tumor thrombi.  相似文献   
96.
A 17-year-old male with attention deficit hyperactivity disorder was admitted to the hospital with generalized weakness. Vital signs and physical examination were normal. Laboratory data were notable for a creatinine of 4.5 mg/dL (baseline 0.6 mg/dL), estimated glomerular filtration rate of 18 ml/min/1.73 m² and hemoglobin 10 g/dL. Urinalysis revealed only 30 mg/dL protein. Serology for autoimmune workup was negative. Renal ultrasound was normal. Kidney biopsy showed noncaseating granulomas and acute on chronic tubulointerstitial nephritis (TIN) with lymphocytes, macrophages, plasma cells and no eosinophils. Acid fast bacilli and Grocott’s methenamine silver stains were negative. Granulomatous interstitial nephritis (GIN) was diagnosed. Prednisone at 60 mg/day was started and tapered. He was then noted to have diarrhea. Colonoscopy showed active enteritis with granulomatous inflammation consistent with Crohn’s disease (CD). Azathioprine was started but due to worsening renal function and diarrhea, it was discontinued. He did not tolerate continued higher doses of prednisone because of mood swings and cushingoid features. Infliximab was initiated with improvement in renal function. There was rapid worsening of renal function when infliximab therapy was interrupted but improved when both prednisone and inflixamb were reinitiated.  相似文献   
97.

Background

While human epidermal growth factor receptor 2 (HER2) overexpression is an adverse breast cancer prognostic factor, it is unclear whether there are differences in outcomes between types of local treatment in this population. This retrospective study examined locoregional recurrence and survival in women with node-negative, HER2+ breast cancer treated with breast-conserving therapy (BCT) versus mastectomy.

Methods

Subjects were 748 patients with pT1–2, N0, M0 HER2+ breast cancer, treated with BCT (n = 422) or mastectomy (n = 326). Trastuzumab was used in 54 % of subjects. The 5-year Kaplan–Meier locoregional recurrence free survival (LRRFS), breast cancer specific survival (BCSS), and overall survival (OS) were compared between cohorts treated with BCT versus mastectomy. Subgroup analyses of LRR and survival were performed separately among patients treated with BCT or mastectomy to examine the effect of trastuzumab on outcomes in each group.

Results

Median follow-up was 4.4 years. Patients treated with mastectomy had higher proportions of grade 3 histology (69 vs 60 %, p = 0.004) and lower rates of hormone therapy (51 vs 64 %, p < 0.001) and trastuzumab therapy (50 vs 57 %, p = 0.04). The 5-year outcomes in women treated with BCT compared with mastectomy were: LRRFS 98.0 versus 98.3 % (p = 0.88), BCSS 97.2 versus 96.1 % (p = 0.70), and OS 95.5 versus 93.4 % (p = 0.19). Trastuzumab was associated with similar LRRFS and improved OS in both local treatment groups.

Conclusions

BCT is safe in the population of women with pT1–2, N0, HER2+ breast cancer, providing high rates of locoregional control and survival equivalent to mastectomy. Trastuzumab was associated with improved survival in both groups.  相似文献   
98.
99.
Chlorotoxin is a small 36 amino-acid peptide identified from the venom of the scorpion Leiurus quinquestriatus. Initially, chlorotoxin was used as a pharmacological tool to characterize chloride channels. While studying glioma-specific chloride currents, it was soon discovered that chlorotoxin possesses targeting properties towards cancer cells including glioma, melanoma, small cell lung carcinoma, neuroblastoma and medulloblastoma. The investigation of the mechanism of action of chlorotoxin has been challenging because its cell surface receptor target remains under questioning since two other receptors have been claimed besides chloride channels. Efforts on chlorotoxin-based applications focused on producing analogues helpful for glioma diagnosis, imaging and treatment. These efforts are welcome since gliomas are very aggressive brain cancers, close to impossible to cure with the current therapeutic arsenal. Among all the chlorotoxin-based strategies, the most promising one to enhance patient mean survival time appears to be the use of chlorotoxin as a targeting agent for the delivery of anti-tumor agents. Finally, the discovery of chlorotoxin has led to the screening of other scorpion venoms to identify chlorotoxin-like peptides. So far several new candidates have been identified. Only detailed research and clinical investigations will tell us if they share the same anti-tumor potential as chlorotoxin.  相似文献   
100.
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