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101.
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Carney complex is a syndrome that may include cardiac and mucocutaneous myxomas, spotting skin pigmentation, and endocrine lesions. Many patients with Carney complex have been shown to have a stop codon mutation in the PRKAR1A gene in the 17q22-24 region. Here we present the case of a 57 year-old man with multiple skin lesions and cardiac myxomas. Histology of the skin lesions showed lentigenous melanocytic hyperplasia and cutaneous myxomas, confirming the diagnosis of Carney complex. Lesional and control normal tissue from the patient were identified and sequenced for the PRKAR1A gene. A germline missense mutation was identified at exon 1A. This is the first report of this mutation, and one of the few reported missense mutation associated with Carney complex. This finding strengthens the argument that there are alternative ways in which the protein kinase A 1-alpha subunit plays a role in tumorigenesis  相似文献   
103.
Background: Bone substitutes of collagenated porcine bone (CPB) have previously been shown to have osteoconductive properties and to be resorbed with time. The influence of different ratios between bone particles and collagen on bone response is not yet known. Purpose: The objective of the study was to evaluate the effect of different collagen ratios on the bone tissue responses to CPB grafts. Materials and Methods: Eight rabbits were used in the study. Bilateral bone defects, 5 × 8 × 3 mm, were created in the maxilla and were filled with 60% CPB/40% collagen gel or with 80% CPB/20% collagen gel. Animals were killed after 8 weeks for histological and morphometrical evaluations. Results: There were no differences between the two biomaterials tested. Both materials showed a high degree of bone formation, 42% and 46%, respectively. Both materials were showing signs of resorption at time of sacrifice. Conclusions: Different collagen/CPB ratios do not influence the bone tissue responses to CPB. Both materials exhibited osteoconductive properties and were starting to be resorbed at 8 weeks.  相似文献   
104.
Polarimetric Synthetic Aperture Radar (PolSAR) imagery can provide valuable observables at different frequencies for classification tasks. In this paper, we assessed separability rate of various polarimetric features in three frequencies of X-, C-, and L- bands. To this end, Jeffries–Matusita distance was firstly used to measure separability of each polarimetric feature in each frequency band. Random Forest classifier was then applied to map various land cover classes in study area. The classification outputs indicated that C-band results were better and more reliable than L-band results and L-band results were subsequently better than X-band results. These results were perfectly compatible with the results obtained by the separability analysis of multifrequency PolSAR features.  相似文献   
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A 42-year-old female presented with subarachnoid hemorrhage (SAH), presumably from a radiation-induced anterior communicating artery aneurysm. Six years earlier, she had undergone radiation treatment for an optic glioma that was diagnosed based on imaging criteria. The aneurysm was successfully clipped, and the optic glioma was biopsied to verify the diagnosis histologically. Radiation-induced cerebral aneurysms often manifest with a fatal SAH. These aneurysms typically develop in the field of radiation and are diagnosed a mean of 8.52 years after radiation. Rarely, the aneurysm sac thromboses spontaneously. Clipping or coiling of the aneurysm can be an effective treatment.  相似文献   
108.
Neurocognitive outcome affects the quality of life of ALL survivors. This study is aimed to assess the prevalence of neurocognitive dysfunction by psychometric and imaging tools in survivors of childhood ALL, treated with 3 different protocols and the effect of time elapsed since the end of chemotherapy. Sixty-two ALL survivors aged 6–18 years and treated in the period 1997–2007 and 60 healthy age and sex matched controls were subjected to neurocognitive testing using Wechsler Intelligence Scale for Children, Benton visual retention (BVRT) and Trail Making test (TMT), followed by diffusion weighed and diffusion tensor MRI for calculation of fraction anisotropy (FA). Survivors underwent revision of protocol and type of CNS therapy. Three different protocols were used: modified BFM 83, BFM 90, and CCG. Survivors treated with modified CCG protocol showed a significant decrease in all cognitive tests compared to control (p<.05); BFM 90 group had a significant lower IQ and longer TMT compared to both control and BFM 83 group and no significant difference was found in results of cognitive tests between BFM 83 and control group. Frontal FA was lower in CCG treated group compared to control, BFM 90 and BFM 83 groups (p<.05); meanwhile it was significantly lower in BFM 90 and BFM 83 groups compared to control group. We concluded that patients treated with modified CCG protocol showed the worst neurocognitive outcome among three assessed protocols. Frontal lobe FA might be an early marker for predicting the neurotoxicity in childhood ALL survivors.  相似文献   
109.
Purpose MRI is considered reference standard for the assessment of left ventricular (LV) volume and mass measurements. There are few accepted guidelines for uniform assessment of cardiac function with MRI. We sought to investigate different confounding factors influencing LV measurement results. Material and Methods In 60 diabetic type-II patients (group A) we compared intra-/inter-reader variability of MRI for cardiac function measured twice at a 3 month interval by one MRI trained reader and one untrained. In 20 patients (group B) two different techniques were compared for determining the epicardial and endocardial LV-borders. Results Bland Altman analysis showed excellent intra-observer measurement agreement for the trained reader 1 for EDM (mean=–2.3 (–23.6–19)), EDV (2.9(–9.2–15.0)), ESV (3.3(–5.8–12.4)) and EF (1.2(–3.3–5.7)). Untrained reader 2 measurement agreement was considerably less appropriate for EDM (mean=–8.2 (–25.8–9.5)), EDV (7.8(–5.1–20.7)), ESV (5.3(–8.0–18.6)). Only for EF (0.8 (–6.5–8.1)) results were comparable to reader 1. Inter-observer measurement in the beginning was poor for EDM (–13.5(–55.6–28.6)) and EDV (7.3(–61.9–76.6)), whereas agreement for ESV (2.1(–29.9–34.2)) and EF (–0.9(–11.6–9.9)) was good. After 3 months, measurement agreement for EDM (–5.3 (–46.4–35.8)) was considerably improved, for EDV (0.4(–67.0–66.2)) was excellent, whereas agreement for ESV (3.1(–34.4–28.1)) and EF (–1.7(–13.0–9.6)) was similar. Using different techniques for determining the epicardial and endocardial borders, only end-diastolic volume was unchanged whereas all other parameters were significantly different using the two methods (p ≤ 0.03). Conclusion Intra- and inter-reader variability, analyst experience as well as different techniques for determining the boundaries of the left ventricle significantly affect MRI parameters for cardiac function. These results suggest a need for developing commonly accepted standards for cardiac MRI evaluation.  相似文献   
110.
Preterm neonates represent one of the most transfused categories of patients. Their target hematocrits, however, are mainly based on expert opinion. The risk of transfusions are very high in the smallest preterm baby with a weak immune response, immature antioxidant ability, fragile germinal matrix and impaired cerebral autoregulation, yet red cell transfusions remain the only life saving measure in the baby with symptomatic anemia.Minimizing phlebotomy losses, following a restrictive transfusion policy and using screened, leukocyte depleted, irradiated, single donor blood remain the best means of avoiding the possible risks while maximizing the benefits of red cell transfusions in the preterm newborn.  相似文献   
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