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81.
Neurosurgeons use ventricular veins during an endoscopic third ventriculocisternostomy as landmark to progress in ventricles. In the current literature, there is lack of detailed intraventricular venous anatomy. Majority of those papers treats Monro’s foramen venous variations. There are no data of third ventricle venous anatomy and variations in the literature. We reported two cases of unusual interthalamic vein that we need to spare during endoscopy.  相似文献   
82.
Hegyi L, Thway K, Fisher C & Sheppard M N
(2012) Histopathology  61, 966–973 Primary cardiac sarcomas may develop from resident or bone marrow‐derived mesenchymal stem cells: use of immunohistochemistry including CD44 and octamer binding protein 3/4 Aims: To provide evidence that cardiac sarcomas ‘not otherwise specified’ express markers that might indicate their cellular origin or identify any lines of differentiation. Methods and results: We reviewed all 11 cases of primary undifferentiated cardiac sarcomas found in the archives of the Royal Marsden and Royal Brompton Hospitals, London, UK during the period 2000–2009. Five cases with appropriate consent and archived material were investigated using immunohistochemistry. We found that the spindle, pleomorphic or occasionally epithelioid cell sarcomas showed no lineage‐specific differentiation other than partial myofibroblastic or ‘myoid’ differentiation (all cases). All tumours showed some degree of cytoplasmic positivity for the mesenchymal stem cell marker CD44. In contrast, no nuclear octamer binding protein 3/4 (Oct3/4) expression was seen in any of the tumours, although very patchy cytoplasmic positivity was seen in some tumours. Conclusions: The cytoplasmic positivity for CD44 and the absence of nuclear Oct3/4 suggest that the cells of these sarcomas may represent ‘daughter’ stem cells that no longer have the capacity for tumour initiation, but have subsequently developed new lines of partial differentiation. Primary cardiac sarcomas may arise from mesenchymal stem cells with the ability to generate tumours with multilineage differentiation.  相似文献   
83.
Biological integration of an implant to surrounding bone is an important event for its clinical success and is driven by numerous factors, including the attraction of bone forming cells. The implant's surface properties influence the initial cell response at the cell/material interface, ultimately affecting the rate and quality of new tissue formation and the stability of the implant. As a consequence, various surface treatments have been developed to increase the clinical performance of titanium-based implants. Among them, the Anodic Plasma-Chemical (APC) technique allows for the combined chemical and morphological modification of titanium surfaces in a single process step. In the present study, we compared the potential of APC surface treatment of high-strength titanium alloys with vacuum plasma spray treatment and yellow gold anodization in supporting osteogenic differentiation of two different osteoprogenitor cell types. Both human fetal osteoblast cell line (hFOB1.19) and human mesenchymal stromal cells showed extensive cell spreading, faster cell growth and differentiation on APC surfaces compared to vacuum plasma spray treated and yellow gold anodized surfaces. Our findings showed that APC titanium-based surfaces provided an effective substrate for osteoprogenitor cells adhesion, proliferation and differentiation.  相似文献   
84.
Epithelioid hemangioma is a rare and benign vascular tumor, most often occurring in the skin. Numerous other localizations, including bones, have been reported. The overall favorable clinical outcome of cutaneous epithelioid hemangioma is now well documented, but it still remains debated in osseous localization, as local recurrences and metastases have been described. We report a case of epithelioid hemangioma of the spine occurring in a 25-year-old male, and discuss main differential diagnoses. Recent studies tend to demonstrate that osseous epithelioid hemangioma, as cutaneous epithelioid hemangioma, should be considered as a benign tumor. Histologically, epithelioid hemangioma consists of a vascular proliferation with diffuse or lobular pattern and features vascular spaces lined by epitheliod endothelial cells with numerous lymphocytes and eosinophils. The main differential diagnosis is represented by epithelioid hemangioendothelioma, the surgical treatment of which must be more aggressive. Precise histological diagnosis is essential for accurate clinical management and to avoid overtreatment.  相似文献   
85.
86.
We tested the use of nasal swabs spotted onto filter paper (Whatman 3M) for the molecular diagnosis of SARS-CoV-2 infection. Spots of a positive nasal swab in conservation medium (B.1.177 strain, 21Ct) were still positive (duo E-gene/IP4) after 10, 20, and 30 days of conservation at room temperature, with Ct values of 28, 27, and 26, respectively. Direct spotting of the swab at bedside (omicron strain) still gave a positive result after 10 days in two RT-qPCR systems: 33.7 Ct using duo E-gene/IP4, and 34.8 using a specific Omicron system. Spotting of a dilution range of media spiked with the Delta (strain 2021/FR/0610, lineage B 1.617.2) and Omicron strains (strain UVE/SARS-CoV-2/2021/FR/1514) showed a threshold of 0.04 TCID50 after 10 days of conservation. We show, for the first time, that this simple and low-cost conservation method can be used to store samples for RT-qPCR against SARS-CoV-2 for up to at least 1 month.  相似文献   
87.
Clémence Jacquin  Emilie Landais  Céline Poirsier  Alexandra Afenjar  Ahmad Akhavi  Nathalie Bednarek  Caroline Bénech  Adeline Bonnard  Damien Bosquet  Lydie Burglen  Patrick Callier  Sandra Chantot-Bastaraud  Christine Coubes  Charles Coutton  Bruno Delobel  Margaux Descharmes  Jean-Michel Dupont  Vincent Gatinois  Nicolas Gruchy  Sarah Guterman  Abdelkader Heddar  Lucas Herissant  Delphine Heron  Bertrand Isidor  Pauline Jaeger  Guillaume Jouret  Boris Keren  Paul Kuentz  Cedric Le Caignec  Jonathan Levy  Nathalie Lopez  Zoe Manssens  Dominique Martin-Coignard  Isabelle Marey  Cyril Mignot  Chantal Missirian  Céline Pebrel-Richard  Lucile Pinson  Jacques Puechberty  Sylvia Redon  Damien Sanlaville  Marta Spodenkiewicz  Anne-Claude Tabet  Alain Verloes  Gaelle Vieville  Catherine Yardin  François Vialard  Martine Doco-Fenzy 《American journal of medical genetics. Part A》2023,191(2):445-458
Chromosome 1p36 deletion syndrome (1p36DS) is one of the most common terminal deletion syndromes (incidence between 1/5000 and 1/10,000 live births in the American population), due to a heterozygous deletion of part of the short arm of chromosome 1. The 1p36DS is characterized by typical craniofacial features, developmental delay/intellectual disability, hypotonia, epilepsy, cardiomyopathy/congenital heart defect, brain abnormalities, hearing loss, eyes/vision problem, and short stature. The aim of our study was to (1) evaluate the incidence of the 1p36DS in the French population compared to 22q11.2 deletion syndrome and trisomy 21; (2) review the postnatal phenotype related to microarray data, compared to previously publish prenatal data. Thanks to a collaboration with the ACLF (Association des Cytogénéticiens de Langue Française), we have collected data of 86 patients constituting, to the best of our knowledge, the second-largest cohort of 1p36DS patients in the literature. We estimated an average of at least 10 cases per year in France. 1p36DS seems to be much less frequent than 22q11.2 deletion syndrome and trisomy 21. Patients presented mainly dysmorphism, microcephaly, developmental delay/intellectual disability, hypotonia, epilepsy, brain malformations, behavioral disorders, cardiomyopathy, or cardiovascular malformations and, pre and/or postnatal growth retardation. Cardiac abnormalities, brain malformations, and epilepsy were more frequent in distal deletions, whereas microcephaly was more common in proximal deletions. Mapping and genotype–phenotype correlation allowed us to identify four critical regions responsible for intellectual disability. This study highlights some phenotypic variability, according to the deletion position, and helps to refine the phenotype of 1p36DS, allowing improved management and follow-up of patients.  相似文献   
88.
Segmentation of lung parenchyma from the chest computed tomography is an important task in analysis of chest computed tomography for diagnosis of lung disorders. It is a challenging task especially in the presence of peripherally placed pathology bearing regions. In this work, we propose a segmentation approach to segment lung parenchyma from chest. The first step is to segment the lungs using iterative thresholding followed by morphological operations. If the two lungs are not separated, the lung junction and its neighborhood are identified and local thresholding is applied. The second step is to extract shape features of the two lungs. The third step is to use a multilayer feed forward neural network to determine if the segmented lung parenchyma is complete, based on the extracted features. The final step is to reconstruct the two lungs in case of incomplete segmentation, by exploiting the fact that in majority of the cases, at least one of the two lungs would have been segmented correctly by the first step. Hence, the complete lung is determined based on the shape and region properties and the incomplete lung is reconstructed by applying graphical methods, namely, reflection and translation. The proposed approach has been tested in a computer-aided diagnosis system for diagnosis of lung disorders, namely, bronchiectasis, tuberculosis, and pneumonia. An accuracy of 97.37 % has been achieved by the proposed approach whereas the conventional thresholding approach was unable to detect peripheral pathology-bearing regions. The results obtained prove to be better than that achieved using conventional thresholding and morphological operations.  相似文献   
89.
IntroductionThere is lack of long-term data outside of controlled clinical trials in carotid artery stenting (CAS). In this study, we compared the short-term outcome, long-term survival, and rate of re-interventions for restenosis in patients after CAS, related to the extent of carotid atherosclerosis classified as single-vessel (unilateral) or double-vessel (bilateral) carotid artery disease.Material and methodsWe retrospectively evaluated 599 patients with significant carotid artery stenosis, who underwent 763 CAS procedures, and used the propensity score to match 226 pairs (452 patients) in the single- or double-vessel carotid disease.ResultsThere was no significant difference in the occurrence of in-hospital major adverse events (3.5% vs. 3.1% of patients in the double-vessel carotid group vs. the single-vessel carotid group; p = 1) The mean follow-up was 6.1 ±4.0 years, and a total of 181 (40%) deaths occurred during 2759 patient-years, which translates into 7.8 and 5.3 deaths per 100 patient-years in the double-vessel carotid group and the single-vessel carotid group, respectively (p < 0.01). The survival in the double-vessel carotid group vs. the single-vessel carotid group at 10 years was 46% (95% CI: 38–54%) vs. 55% (95% CI: 47–63%) (p < 0.01). Twenty-four (11%) patients and 6 (3%) patients underwent re-interventions for restenosis in the double-vessel and the single-vessel carotid disease group, respectively (p < 0.01).ConclusionsPatients with CAS and significant double-vessel carotid artery disease had similar peri-procedural risk, but had a worse long-term survival, and a higher rate of re-interventions for restenosis compared to the single-vessel carotid artery disease patients.  相似文献   
90.
The aim of this study was to compare the efficacy of trisacryl gelatin microspheres versus polyvinyl alcohol particles (PVA) in the preoperative embolization of bone neoplasms, on the basis of intraoperative blood loss quantified by the differences in preoperative and postoperative hematic levels of hemoglobin, hematocrit and erythrocytes count. From January 1997 to December 2002, preoperative embolization of bone tumors (either primary or secondary) was carried out in 49 patients (age range 12/78), 20 of whom were treated with trysacril gelatin microspheres (group A) and 29 with PVA particles (group B). The delay between embolization and surgery ranged from 1 to 13 days in group A and 1 to 4 days in group B. As used in international protocols, we considered hematic levels of hemoglobin, hematocrit and erythrocytes count for the measurement of intraoperative blood loss then the differences in pre- and postoperative levels were used as statistical comparative parameters. We compared the values of patients treated with embospheres (n = 10) and PVA (n = 18) alone, and patients treated with (group A = 10; group B = 11) versus patients treated without other additional embolic materials in each group (group A = 10; group B = 18). According to the Students t-test (p < 0.05), the difference of hematic parameters between patients treated by embospheres and PVA alone were significant; otherwise there was no significant difference between patients treated with only one embolic material (embospheres and PVA) versus those treated with other additional embolic agents in each group. The patients treated with microspheres had a minor quantification of intraoperative blood loss compared to those who received PVA particles. Furthermore, they had a minor increase of bleeding related to the delay time between embolization and surgery. The use of additional embolic material did not improve the efficacy of the procedure in either group of patients.  相似文献   
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