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101.
102.
Lorraine Pan Lan Peng J Jean-Gilles Ximin Zhang Rosemary Wieczorek Shilpa Jain Vicki Levine Iman Osman Victor G Prieto Peng Lee 《International journal of clinical and experimental pathology》2010,3(5):545-548
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.
Ulf Nannmark DDS PhD Iman Azarmehr UDS 《Clinical implant dentistry and related research》2010,12(2):161-163
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
105.
106.
107.
Kemal Yucesoy Iman Feiz-Erfan Robert F. Spetzler Patrick P. Han Stephen Coons 《Skull base》2004,14(3):169-173
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.
Mohsen ElAlfy Iman Ragab Inas Azab Shaimaa Amin Marwa Abdel-Maguid 《Pediatric hematology and oncology》2014,31(2):194-204
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.
Henning Steen Khurram Nasir Ellen Flynn Iman El-Shehaby Shenghan Lai Hugo A. Katus David Bluemcke João A. C. Lima 《Clinical research in cardiology》2007,96(10):743-751
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.
Iman F. Iskander Khaled M. Salama Rasha M. Gamaleldin Jerard Seghatchian 《Transfusion and apheresis science》2018,57(3):431-436
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