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31.
P Veluvolu B D Collier A T Isitman G F Carrera R S Hellman S Fry 《Clinical nuclear medicine》1984,9(11):631-634
Although the "doughnut" sign in brain scintigraphy is a well known phenomenon, similar findings have recently been reported in bone scintigraphy in osseous and nonosseous lesions. A skeletal doughnut sign in bone scintigraphy caused by giant cell tumor of the proximal fibula is presented with a brief review of literature. 相似文献
32.
Relationships Between Mycoplasma pneumoniae and Human Respiratory Epithelium 总被引:15,自引:32,他引:15 下载免费PDF全文
The interaction was studied between Mycoplasma pneumoniae and its natural host cell, the human respiratory epithelium. Organized, ciliated cells provided by fetal trachea in organ culture enabled examination of the host-parasite relationship by light, immunofluorescence, and electron microscopy. Impairment of cellular function was reflected by disorganization and loss of ciliary motion; this was associated with a sequence of cytopathological changes denoting progressive cell injury. The organisms were found concentrated on the luminal surface of ciliated epithelium and cells lining the submucosal glands. A differentiated portion of the Mycoplasma, consisting of an extension of the unit membrane containing an electron-dense core surrounded by a lucent space, served as the means of attachment to host cells. The findings suggest that the pathogenicity of M. pneumoniae depends upon intimate extracellular infection with production of functional and structural changes initiated by host cell membrane injury. 相似文献
33.
Chest pain with nondiagnostic electrocardiogram in the emergency department: a randomized controlled trial of two cardiac marker regimens 总被引:3,自引:0,他引:3 下载免费PDF全文
E Dagnone C Collier W Pickett N Ali M Miller D Tod R Morton 《Canadian Medical Association journal》2000,162(11):1561-1566
BACKGROUND: Early detection of acute myocardial infarction (AMI) may save lives. In the emergency setting, it is unclear whether the early use of certain cardiac markers (myoglobin and cardiac troponin I [cTnI]) assists in making appropriate decisions whether to admit or discharge patients with chest pain of possible ischemic cause who have nondiagnostic electrocardiograms (ECGs). We performed a study to determine whether the addition of new cardiac markers in the emergency department results in improved clinical decisions. METHODS: A single-blind randomized controlled trial was conducted between June 1997 and June 1998 in a tertiary care emergency department in Kingston, Ont. Of 296 patients aged 30 years or more who presented to the emergency department with chest pain and nondiagnostic ECGs, 146 were randomly assigned to the intervention group (determination of baseline creatine kinase [CK] level, CK MB fraction and cTnI level, and myoglobin level at baseline and at 2 hours) and 150 to the control group (determination of baseline CK level and CK MB fraction). Outcome measures included the rate of admission to the inpatient cardiology service and length of stay in the emergency department. RESULTS: Of the 296 patients, 34 (11.5%) received a diagnosis of AMI in the emergency department, and 92 (31.1%) had chest pain of noncardiac cause. Patients in the intervention group were less likely than those in the control group to be admitted to the cardiology service (67 [45.9%] v. 81 [54.0%]). The absolute difference in the proportion (8.1% [95% confidence interval -3.3 to 19.5]), although potentially important clinically, was not statistically significant. The length of stay in the emergency department was essentially the same in the 2 study groups. At 30 days, the proportions of patients with a diagnosis of recurrent angina (58.2% in the intervention group and 58.0% in the control group) and AMI (12.3% and 14.7%) were also similar. INTERPRETATION: The optimal cardiac marker panel to be used in the emergency department remains unknown. The addition of serial testing of myoglobin with cTnI confirmation to the standard panel did not substantially change the clinical management or outcomes of patients presenting with chest pain and nondiagnostic ECGs. 相似文献
34.
Harry T. Whelan Lucy H. Kras Kutlan Ozker Dawn Bajic Meic H. Schmidt Yu Liu Lisa Ann Trembath Fusun Uzum Glenn A. Meyer Annette D. Segura B. David Collier 《Journal of neuro-oncology》1994,22(1):7-13
The use of PHOTOFRIN for photodynamic therapy of human gliomas has been studied by i.v. administration and laser photosensitization. Defining the uptake of PHOTOFRIN in the patient's tumor in comparison with the surrounding normal brain tissue is highly desirable for patient selection and study ofin vivo kinetics. We utilized a non-invasive approach to the detection of PHOTOFRIN uptake in brain tumors with111In-oxine radiolabeled PHOTOFRIN and external imaging and quantitation using a gamma camera. Biodistribution of111In-labeled PHOTOFRIN in 13 organs was determined in four dogs and 15 mice with gliomas.99mTc-DTPA was used as a control for nonspecific uptake. The greatest concentration of111In-PHOTOFRIN in the brain tumor occurred at 24 hours post i.v. administration. The brain tumor PHOTOFRIN uptake was seven times greater than that of normal brain. The decreased blood background at 72 hours made this the optimum time for imaging. Specific tumor tissue uptake of111In-PHOTOFRIN occurred, well beyond that resulting from blood-brain-barrier (BBB) breakdown. 相似文献
35.
Myles-Worsley M Coon H Tiobech J Collier J Dale P Wender P Reimherr F Polloi A Byerley W 《American journal of medical genetics》1999,88(1):4-10
We are studying the genetic etiology of schizophrenia in the Republic of Palau, a remote island nation in Micronesia that has been geographically and ethnically isolated for approximately 2,000 years. The first epidemiological phase sought to estimate the lifetime prevalence of schizophrenia and evaluate the familiality of the illness based on complete ascertainment of cases and families segregating schizophrenia. A total of 160 strictly defined cases of schizophrenia were ascertained in a population of 13,750 adults who were 15 years of age and older. The lifetime prevalence of strictly defined schizophrenia in Palau was 1.99% overall and 2.77% in males vs. 1.24% in females. This greater than 2:1 male-to-female risk ratio for schizophrenia was accompanied by an earlier mean age of onset for males (23.3 years) than for females (27.5 years). These 160 cases of strict schizophrenia represent 59 separate families each identified by a single common founder. Eleven of these families have 5 to 14 cases and represent nearly half of the strict schizophrenia cases in Palau. Although schizophrenia is clearly aggregating in these 11 families, cases are distributed sparsely throughout the large sibships. In the entire sample of 160 cases of strict schizophrenia, there were only 11 sib-pairs and 2 sib-trios. When a family was defined to include third-degree relatives, only 11 cases (6.9%) were nonfamilial. The majority of the ascertained cases can be linked together into extended pedigrees with complex multilineal inheritance patterns. These intricately interconnected families may pose challenges for traditional linkage techniques. However, these Palauan families represent a valuable resource for studying the genetic etiology of schizophrenia because there may be fewer susceptibility genes for schizophrenia in this genetic isolate than in the heterogeneous populations that are common throughout the world today. 相似文献
36.
37.
Why obstetric epidurals fail: a study of epidurograms 总被引:2,自引:0,他引:2
Collier CB 《International Journal of Obstetric Anesthesia》1996,5(1):19-31
In a study of the factors involved in the occasional failure of continuous obstetric epidural blockade, contrast injections through epidural catheters and radiographic screening were undertaken in 35 postpartum patients. The two major causes of inadequate block were found to be transforaminal escape of the catheter tip, and persistent unilateral block associated with an obstructive barrier in the epidural space. Recommendations for overcoming these problems are discussed. 相似文献
38.
William T. Roubal Tracy K. Collier Donald C. Malins 《Archives of environmental contamination and toxicology》1977,5(1):513-529
Carbon-14 labeled benzene, naphthalene, and anthracene were administered to young coho salmon (Oncorhynchus kisutch) in the food and by intraperitoneal injection. Regardless of the mode of application the accumulated carbon-14 (% administered dose) in key organs (e.g., liver and brain) increased in the order anthracene > naphthalene > benzene over various time periods. The metabolic fate of the hydrocarbons after intraperitoneal injection was studied. It was shown that the highest percentages of metabolites occurred in the gall bladder; however, significant amounts were also found in the liver, brain, flesh, and carcass. Solvent partition and thin-layer chromatographic techniques were developed to determine the structure of individual metabolites. In brain, liver, and gall bladder, 1-naphthol and 1-naphthyl glucuronic acid were major products of naphthalene metabolism; however, glycoside/sulfate fractions and mercapturic acid were indicated. The heart and flesh were rich in 1-naphthol and the former organ contained significant amounts of 1,2-dihydro-1,2-dihydroxynaphthalene. The findings indicated that the aromatic hydrocarbons in key organs increased in relation to the number of benzenoid rings. Further, it appears that aromatic metabolites are broadly distributed throughout fish exposed to polynuclear aromatic hydrocarbons. 相似文献
39.
Michael WJ Hii Robert N Gibson Anthony G Speer Neil A Collier Noel Sherson Cate Jardine 《Journal of Medical Imaging and Radiation Oncology》2003,47(4):393-403
We reviewed the results of percutaneous intervention of hilar biliary malignancy over a 10‐year period at a single institution: the Royal Melbourne Hospital. Ninety‐nine patients (100 treated in total) were included. Information was retrieved by retrospective examination of patient notes and radiology, combined with interviews with family and relevant physicians. Sixty‐nine patients were treated with insertion of semipermanent stents, 19 had external drain tubes, and 25 received percutaneous access for Iridium brachytherapy. Adequate drainage was achieved in 87% of the patients stented, and percutaneous access was successful in 96% of patients planned for brachytherapy. Of those patients undergoing endoprosthesis insertion, early complications occurred in 39% and late complications in 23%. Average survival for the entire patient population was 227.3 days, with a median of 167 days. Longer survival times (213 vs 142 days) and lower complication rates (44 vs 64%) are observed with metal stents in comparison with plastic stents. Percutaneous intervention is an important treatment option in hilar biliary malignancy, particularly in patients unfit for surgery. Reasonable survival with good palliation is the most common outcome, and most patients do not require further intervention. 相似文献
40.
Anne L Clark Ann M Gillenwater Thomas G Collier Reza Alizadeh-Naderi Adel K El-Naggar Rebecca R Richards-Kortum 《Clinical cancer research》2003,9(13):4714-4721
PURPOSE: The goal of this study was to characterize features of normal and neoplastic oral mucosa using reflectance confocal microscopy. EXPERIMENTAL DESIGN: Oral cavity biopsies were acquired from 17 patients at the Head and Neck Clinic of The University of Texas M. D. Anderson Cancer Center who were undergoing surgery for squamous cell carcinoma within the oral cavity. Reflectance confocal images were obtained at multiple image plane depths from biopsies within 6 h of excision. After imaging, biopsies were fixed in 10% formalin and submitted for routine histological examination. Reflectance confocal images were compared with histological images from the same sample to determine which tissue features contribute to image contrast and can be potentially imaged using in vivo confocal microscopy. RESULTS: Confocal images were successfully acquired from 15 biopsy pairs from 17 patients. Depth-related changes in cell diameter and nuclear density were observed at multiple anatomical sites within the oral cavity. In squamous cell carcinomas, densely packed, pleomorphic tumor nuclei could be visualized with distinct differences in nuclear density and morphology distinguishable between confocal images of neoplastic and nonneoplastic oral cavity. Other features of noncancerous and cancerous oral tissue that could be identified in the confocal images included areas of inflammation, fibrosis, muscle fibers, and salivary glands. CONCLUSIONS: Our results support the potential for this tool to play a significant role in the clinical evaluation of oral lesions, real-time identification of tumor margins, and monitoring of response to therapeutic treatment. 相似文献