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51.
52.

Background

The purpose of this study is to report a modified transtibial technique to approach the center of anatomical femoral footprint in anterior cruciate ligament (ACL) reconstruction and to investigate the accurate femoral tunnel position with 3-dimensional computed tomography (3D-CT) and radiography after reconstruction.

Methods

From December 2010 to October 2011, we evaluated 98 patients who underwent primary ACL reconstruction using a modified transtibial technique to approach the center of anatomical femoral footprint in single bundle ACL reconstruction with hamstring autograft. Their femoral tunnel positions were investigated with 3D-CT and radiography postoperatively. Femoral tunnel angle was measured on the postoperative anteroposterior (AP) radiograph and the center of the femoral tunnel aperture on the lateral femoral condyle was assessed with 3D-CT according to the quadrant method by two orthopedic surgeons.

Results

According to the quadrant method with 3D-CT, the femoral tunnel was measured at a mean of 32.94% ± 5.16% from the proximal condylar surface (parallel to the Blumensaat line) and 41.89% ± 5.58% from the notch roof (perpendicular to the Blumensaat line) with good interobserver (intraclass correlation coefficients [ICC], 0.766 and 0.793, respectively) and intraobserver reliability (ICC, 0.875 and 0.893, respectively). According to the radiographic measurement on the AP view, the femoral tunnel angles averaged 50.43° ± 7.04° (ICC, 0.783 and 0.911, respectively).

Conclusions

Our modified transtibial technique is anticipated to provide more anatomical placement of the femoral tunnel during ACL reconstruction than the former traditional transtibial techniques.  相似文献   
53.

Objective

Attention deficit hyperactivity disorder (ADHD) is common disorder of the school-age population. ADHD is familial and genetic studies estimate heritability at 80–90%. The aim of the present study was to investigate the association between the genetic type and alleles for RELNgene (rs736707, rs2229864, rs362746, rs362726, rs362691, rs1062831, rs607755, and rs2072403) in Korean children with ADHD.

Methods

The sample consisted of 180 ADHD children and 159 control children. We diagnosed ADHD according to DSM-IV. ADHD symptoms were evaluated with Conners'' Parent Rating Scales and Dupaul Parent ADHD Rating Scales. Blood samples were taken from the 339 subjects, DNA was extracted from blood lymphocytes, and PCR was performed for RELN Polymorphism. Alleles and genotype frequencies were compared using the chi-square test. We compared the allele and genotype frequencies of RELN gene polymorphism in the ADHD and control groups.

Results

This study showed that there was a significant correlation among the frequencies of the rs736707 (OR=1.40, 95% CI=1.03–1.90, p=0.031) of alleles of RELN, but the final conclusions are not definite.

Conclusion

Follow up studies with larger patient or pure subgroups are expected. These results suggested that RELN might be related to ADHD symptoms.  相似文献   
54.

Purpose  

The clinical importance of intraductal papillary mucinous neoplasm of the pancreas (IPMN) has been increasing with a large number of newly diagnosed IPMN. This study was designed to explore the characteristics of resected IPMN and to determine the predictive factors for malignant and invasive IPMN.  相似文献   
55.

Objectives

To establish the undisputed the value of washout rate for adrenal adenoma using delayed enhanced CT, we evaluated diagnostic performance of cut-off value and delayed time of washout rate by final pathologic diagnosis in a multicenter study.

Methods

We reviewed the pathologic and clinical records of 244 patients underwent adrenalectomies at 5 university hospitals between 2005 and 2009. We calculated the mean Housfield units (HU) of adrenal lesion at non-enhancing CT, and early and delayed enhanced CT using the region of interest. We used ROC curves to determine the specificity and sensitivity of non-enhanced CT scans and the washout rate according to the various cut-off for adrenal adenomas.

Results

We divided the patients into adrenal adenoma group (n?=?138) and non-adrenal adenoma group (n?=?106) based on final pathologic report. Using the unenhanced images with a threshold of 10 HU, the sensitivity was 45.7?%, and the specificity was 97.1?%. Using the 15-min-washout rate with a threshold of 55?%, the sensitivity was 93.9?%, and the specificity was 95.8?%.

Conclusions

Regardless of various CT machines and protocols, a washout rate of 15-min-delayed CT was most useful in the diagnosis of adrenal adenomas due to the early inflow and outflow of contrast media in the tissues of adrenal adenomas.  相似文献   
56.
We investigated the role of donor bone marrow cell (DBMC) infusions in immunosuppression withdrawal in adult liver transplantation. Patients enrolled were at least 3 years post-transplantation, with stable graft function. Forty-five (study group: G1) received DBMC, and 59 (control group: G2) did not. Immunosuppression was reduced by one third upon enrollment, by another third the second year of the study and was completely withdrawn the third year. Patient and graft survival were similar between the two groups. Although rejection episodes were significantly less in G1 the first 2 years of the study (35% vs. 57%, p = 0.016), there was no significant difference overall (74% vs. 81%, p = 0.14). Until February 2004, 20 patients, 10 in each group, were immunosuppression free for 1-3 years. Approximately 20% of long-term survivors of liver transplantation can successfully discontinue their immunosuppression. DBMC infusions, do not increase this likelihood.  相似文献   
57.
OBJECTIVES: The objectives of this study were to analyze the actual long-term outcome after the surgical resection of extrahepatic bile duct cancer and to identify the characteristics shared by long-term survivors (5 years or longer). SUMMARY BACKGROUND DATA: Although reported 5-year survival rates of extrahepatic bile duct cancer lie between 20% and 30%, these data are not reflecting the actual cure rate. Some patients survive longer than 5 years with recurrent disease. In some patients, recurrence is detected after 5 years. Accordingly, true cure rate is probably substantially lower than the 5-year survival rate. METHODS: One hundred fifty-one patients from a total of 282 patients with extrahepatic bile duct cancer (excluding ampulla of Vater cancer) underwent surgical resection between 1986 and 1997. We analyzed the actual survival outcome and postresection prognostic factors after resection, which included hepatobiliary resection (HBR; extended either right or left hepatectomy, caudate lobectomy, and hilar bile duct resection, n = 23), bile duct resection (BDR; n = 25), and pancreatoduodenectomy (PD; n = 103). We also compared the clinicopathologic characteristics of actual long-term survivors (n = 49) with those who survived longer than 5 years and with short-term (<5 years) survivors. RESULTS: Forty-nine of the 151 resection cases (32.5%) survived 5 years or longer; there was no 5-year survivor in the nonresected cases. The actual 5-year survival rate was 47.8% after HBR (11 of 23), 28.0% after BDR (7 of 25), and 30.1% after PD (31 of 103) (P = 0.083). Tumor histology and lymph node metastasis were identified as independent prognostic factors by multivariate analysis. Some long-term survivors had poor postoperative prognostic factors such as T3, lymph node metastasis, or microscopic margin involvement, but none with a poorly differentiated tumor. Seven long-term survivors had recurrent disease at 5 years, and recurrence was detected after 5 years in 8 more patients. Therefore, the actual cure rate (<19.2%) was substantially less than the 5-year survival rate. CONCLUSIONS: In cases of extrahepatic bile duct cancer, resection should be considered and efforts should be made to obtain a tumor-free margin. An aggressive surgical approach will give some survival benefit to the patients with even advanced disease. Long-term follow up is needed before declaring "a cure," because late recurrence after 5 years is detected not infrequently. Adjuvant therapy, local and systemic, needs to be further developed.  相似文献   
58.
ObjectiveTo investigate the image quality (IQ) and apparent diffusion coefficient (ADC) of reduced field-of-view (FOV) di-ffusion-weighted imaging (DWI) of pancreas in comparison with full FOV DWI.ResultsOn qualitative analysis, reduced FOV DWI showed better anatomic structure visualization (2.76 ± 0.79 at b = 0 s/mm2 and 2.81 ± 0.64 at b = 400 s/mm2), lesion conspicuity (3.11 ± 0.99 at b = 0 s/mm2 and 3.15 ± 0.79 at b = 400 s/mm2), IQ score (8.51 ± 2.05 at b = 0 s/mm2 and 8.79 ± 1.60 at b = 400 s/mm2), and higher clinical utility (3.41 ± 0.64), as compared to full FOV DWI (anatomic structure, 2.18 ± 0.59 at b = 0 s/mm2 and 2.56 ± 0.47 at b = 500 s/mm2; lesion conspicuity, 2.55 ± 1.07 at b = 0 s/mm2 and 2.89 ± 0.86 at b = 500 s/mm2; IQ score, 7.13 ± 1.83 at b = 0 s/mm2 and 8.17 ± 1.31 at b = 500 s/mm2; clinical utility, 3.14 ± 0.70) (p < 0.05). Artifacts were significantly improved on reduced FOV DWI (2.65 ± 0.68) at b = 0 s/mm2 (full FOV DWI, 2.41 ± 0.63) (p < 0.001). On quantitative analysis, there were no significant differences between the 2 DWI sequences in ADCs of various pancreatic lesions and parenchyma (p > 0.05). ADCs of adenocarcinomas (1.061 × 10-3 mm2/s ± 0.133 at reduced FOV and 1.079 × 10-3 mm2/s ± 0.135 at full FOV) and neuroendocrine tumors (0.983 × 10-3 mm2/s ± 0.152 at reduced FOV and 1.004 × 10-3 mm2/s ± 0.153 at full FOV) were significantly lower than those of parenchyma (1.191 × 10-3 mm2/s ± 0.125 at reduced FOV and 1.218 × 10-3 mm2/s ± 0.103 at full FOV) (p < 0.05).ConclusionReduced FOV DWI of the pancreas provides better overall IQ including better anatomic detail, lesion conspicuity and subjective clinical utility.  相似文献   
59.
ObjectiveTo evaluate the image characteristics of subtraction magnetic resonance venography (SMRV) from time-resolved contrast-enhanced MR angiography (TRMRA) compared with phase-contrast MR venography (PCMRV) and single-phase contrast-enhanced MR venography (CEMRV).ResultsSingle-phase contrast-enhanced MR venography showed better image quality (median score 4 in both reviewers) than did the other two MRVs (p < 0.001), whereas SMRV (median score 3 in both reviewers) and PCMRV (median score 3 in both reviewers) had similar image quality (p ≥ 0.951). SMRV (median score 0 in both reviewers) suppressed arterial signal better than did the other MRVs (median score 1 in CEMRV, median score 2 in PCMRV, both reviewers) (p < 0.001). The dural sinus score of SMRV (median and interquartile range [IQR] 48, 43-50 for reviewer 1, 47, 43-49 for reviewer 2) was significantly higher than for PCMRV (median and IQR 31, 25-34 for reviewer 1, 30, 23-32 for reviewer 2) (p < 0.01) and did not differ from that of CEMRV (median and IQR 50, 47-52 for reviewer 1, 49, 45-51 for reviewer 2) (p = 0.146 in reviewer 1 and 0.123 in reviewer 2). The SNR and CNR of SMRV (median and IQR 104.5, 83.1-121.2 and 104.1, 74.9-120.5, respectively) were between those of CEMRV (median and IQR 150.3, 111-182.6 and 148.4, 108-178.2) and PCMRV (median and IQR 59.4, 49.2-74.9 and 53.6, 43.8-69.2).ConclusionSubtraction magnetic resonance venography is a promising MRV method, with acceptable image quality and good arterial suppression.  相似文献   
60.
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