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1.
Helms  CA; Kaban  LB; McNeill  C; Dodson  T 《Radiology》1989,172(3):817-820
Magnetic resonance (MR) imaging has been used in the temporomandibular joint (TMJ) primarily to define the disk position. This report examines altered morphology and signal intensity characteristics of the TMJ disk as they relate to the severity of internal derangement. Two hundred sixteen joints in 133 patients with a history of such derangement. were imaged with MR. Disk position, signal intensity, morphology, and the presence of osteoarthritis were determined for each joint. The normal disk was not anteriorly displaced and had a normal "bow-tie" shape. A grade 1 disk was anteriorly displaced and had a normal shape; a grade 2 disk was anteriorly displaced and had an abnormal shape. Forty (19%) joints were considered normal; none of these exhibited osteoarthritis. One hundred thirty-nine (64%) joints were grade 1; osteoarthritis was found in 17%. Thirty-seven (17%) were grade 2; osteoarthritis was found in 95%. All forty normal joints had high or intermediate signal intensity in the disk. Osteoarthritic joints had a higher percentage of disks with diminished intensity (P less than .0001). Severe or untreated osteoarthritis is known to be a complication of TMJ internal derangements; hence this grading system seems to correlate with the severity of internal derangement.  相似文献   
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AIMS AND BACKGROUND: Knowledge of the steroid hormone receptors has proved to be of significant value in breast cancer. In the present study the possible importance of estrogen-regulated pS2 protein was investigated. Our direct purpose was to answer the question whether the expression of pS2 may be a marker of functional heterogeneity with respect to the steroid hormone receptor status. METHODS AND STUDY DESIGN: The study included 152 patients with primary, operable, histologically confirmed breast carcinomas. Histology specimens were reviewed and classified according to type, nodal status, tumor size and grade. Steroid hormone receptors were assayed by biochemical methods according to the procedures recommended by the EORTC. pS2 protein measurement was performed in breast carcinoma cytosols using an immunoradiometric assay. The results were analyzed by non-parametric statistical methods. RESULTS: A statistically significant inverse correlation between pS2 protein expression and histological tumor grade was found. The expression of pS2 protein was confirmed to be correlated with steroid hormone receptor status. However, it is important to point out that in spite of these statistically significant findings there were no significant biological associations due to overlapping individual pS2 protein values. The baseline level of expression of pS2 protein was obtained in histological grade III carcinomas with a negative steroid hormone receptor status. It was shown that the distribution of carcinomas according to the baseline level of pS2 protein expression was heterogeneous among estrogen receptor-positive carcinomas, and strikingly homogeneous among estrogen and progesterone-negative carcinoma. CONCLUSION: Our study suggested that PR and pS2 protein may identify distinct subsets of estrogen receptor-positive breast carcinomas.  相似文献   
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BB-10010 is a genetically engineered variant of human macrophage inflammatory protein-1 alpha with improved solution properties. We show here that it mobilizes stem cells into the peripheral blood. We investigated the mobilizing effects of BB-10010 on the numbers of circulating 8-day spleen colony-forming units (CFU-S8), CFU-S12, and progenitors with marrow repopulating ability (MRA). A single subcutaneous dose of BB-10010 caused a twofold increase in circulating numbers of CFU-S8, CFU-S12, and MRA 30 minutes after dosing. We also investigated the effects of granulocyte colony-stimulating factor (G- CSF) and the combination of G-CSF with BB-10010 on progenitor mobilization. Two days of G-CSF treatment increased circulating CFU-S8, CFU-S12, and MRA progenitors by 25.7-, 19.8-, and 27.7-fold. A single administration of BB-10010 after 2 days of G-CSF treatment increased circulating CFU-S8, CFU-S12, and MRA even further to 38-, 33-, and 100- fold. Splenectomy resulted in increased circulating progenitor numbers but did not change the pattern of mobilization. Two days of treatment with G-CSF then increased circulating CFU-S8, CFU-S12, and MRA by 64-, 69-, and 32-fold. A single BB-10010 administration after G-CSF treatment further increased them to 85-, 117-, and 140-fold, respectively, compared with control. We conclude that BB-10010 causes a rapid increase in the number of circulating hematopoietic progenitors and further enhances the numbers induced by pretreatment with G-CSF. BB- 10010 preferentially mobilized the more primitive progenitors with marrow repopulating activity, releasing four times the number achieved with G-CSF alone. Translated into a clinical setting, this improvement in progenitor cell mobilization may enhance the efficiency of harvest and the quality of grafts for peripheral blood stem cell transplantation.  相似文献   
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Purpose

Image guidance for minimally invasive surgery is based on spatial co-registration and fusion of 3D pre-interventional images and treatment plans with the 2D live intra-interventional images. The spatial co-registration or 3D–2D registration is the key enabling technology; however, the performance of state-of-the-art automated methods is rather unclear as they have not been assessed under the same test conditions. Herein we perform a quantitative and comparative evaluation of ten state-of-the-art methods for 3D–2D registration on a public dataset of clinical angiograms.

Methods

Image database consisted of 3D and 2D angiograms of 25 patients undergoing treatment for cerebral aneurysms or arteriovenous malformations. On each of the datasets, highly accurate “gold-standard” registrations of 3D and 2D images were established based on patient-attached fiducial markers. The database was used to rigorously evaluate ten state-of-the-art 3D–2D registration methods, namely two intensity-, two gradient-, three feature-based and three hybrid methods, both for registration of 3D pre-interventional image to monoplane or biplane 2D images.

Results

Intensity-based methods were most accurate in all tests (0.3 mm). One of the hybrid methods was most robust with 98.75% of successful registrations (SR) and capture range of 18 mm for registrations of 3D to biplane 2D angiograms. In general, registration accuracy was similar whether registration of 3D image was performed onto mono- or biplanar 2D images; however, the SR was substantially lower in case of 3D to monoplane 2D registration. Two feature-based and two hybrid methods had clinically feasible execution times in the order of a second.

Conclusions

Performance of methods seems to fall below expectations in terms of robustness in case of registration of 3D to monoplane 2D images, while translation into clinical image guidance systems seems readily feasible for methods that perform registration of the 3D pre-interventional image onto biplanar intra-interventional 2D images.
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In accordance with increased proliferation in myeloproliferative neoplasm (MPN), the goal is to evaluate the immunoexpression of: β-catenin, PPAR-γ and Ki67 protein, to compare them with bone marrow ultrastructural characteristics in patients with MPN. Immunoexpression and electron microscopy of bone marrow was analyzed in 30 Ph-negative MPN patients, including per 10 patients with polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF). The quantity of β-catenin immunoreactive cells was significantly higher in PV then in ET (p < 0.01) or PMF group of patients (p < 0.01) and also in ET versus PMF group of patients (p < 0.01). Erythroid lineage showed absent β-catenin staining without immunoreactivity in nucleus. In contrast, immunoreactivity for PPAR-γ was localized mostly in megakaryocytes and the highest number of PPAR-γ immunopositive cells was detected in PMF group of patients. In addition, the proliferative Ki67 index was significantly increased in the PMF and PV patients compared to patients with ET. Also, the megakaryocytes showed abnormal maturation in PMF group of patients as determined by ultrastructural analysis. These results indicated that PV dominantly expressed β-catenin and proliferation marker Ki67 in bone marrow, while PMF is linked preferentially to PPAR-γ immunopositive megakaryocytes characterized by abnormal maturation.  相似文献   
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Aims

Long-term hyperglycemia, characteristic for type 1 diabetes, causes enhanced oxidative stress, chronic inflammation and endothelial dysfunction which are the key events in the development of vascular complications. On the other hand, some data shows that existence of chronic degenerative complications may cause increased inflammatory marker levels in diabetic patients, mainly as a repercussion of malfunctioned endothelial repair process. Our study aims to determinate a degree of inflammation in type 1 diabetes patients and to investigate its relation to development of the chronic microvascular complications.

Methods

General information, anthropometric, glucose metabolism, lipid and lipoprotein parameters, levels of C reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were analyzed and screening tests for detection of the chronic microvascular complications were conducted in 76 type 1 diabetes patients.

Results

Forty six patients had at least one of the complications. They were older and had longer duration of diabetes (p=0.015; p<0.0001) and higher values of total (p=0.021), LDL-cholesterol (p=0.048) and triglycerides (p=0.002). Levels of CRP (p=0.004) and TNF-α (p=0.048) were higher in patients with chronic microvascular complications in regard to patients without diagnosed microangiopathy.

Conclusion

Low grade chronic inflammation is characteristic for type 1 diabetes patients with developed chronic microvascular complications.  相似文献   
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