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21.
Somak Roy Kajal Kiran Dhingra Parul Gupta Nita Khurana Bulbul Gupta Ravi Meher 《Head and neck pathology》2009,3(2):163-168
Primary salivary gland carcinoma with neuroendocrine differentiation is of rare occurrence, especially so in the parotid gland.
Amongst the various reported primary tumors with neuroendocrine differentiation, acinic cell carcinoma (ACC) one such tumor.
A 48 year old lady presented with a gradually increasing right infra-auricular swelling for a period of 1 year which enlarged
suddenly in a short period. Contrast Enhanced Computed Tomography (CECT) suggested diagnosis of Pleomorphic Adenoma. Fine
Needle Aspiration Cytology (FANC) yielded a cystic fluid suggesting a possibility of Warthin’s tumor or Oncocytic lesion.
Intraoperative findings were suggestive of a Warthin’s tumor. Initial histopathological examination of the tumor was suggestive
of neuroendocrine carcinoma. However, extensive sectioning revealed peripheral islands of ACC. Immunoexpression of S-100,
Neuron specific Enolase (NSE), Chromogranin A and Synaptophysin confirmed the diagnosis. The possibility of neuroendocrine
differentiation in a primary salivary gland tumor should be kept in mind whenever a salivary gland tumor shows only neuroendocrine
histology. 相似文献
22.
Christopher L. Hansen Richard A. Goldstein Olakunle O. Akinboboye Daniel S. Berman Elias H. Botvinick Keith B. Churchwell C. David Cooke James R. Corbett S. James Cullom Seth T. Dahlberg Regina S. Druz Edward P. Ficaro James R. Galt Ravi K. Garg Guido Germano Gary V. Heller Milena J. Henzlova Mark C. Hyun Lynne L. Johnson April Mann Benjamin D. McCallister Robert A. Quaife Terrence D. Ruddy Senthil N. Sundaram Raymond Taillefer R. Parker Ward John J. Mahmarian 《Journal of nuclear cardiology》2007,14(6):e39-e60
23.
24.
Neuropathogenesis of Chimeric Simian/Human Immunodeficiency Virus infection In Pig-tailed and Rhesus Macaques 总被引:2,自引:0,他引:2
Ravi Raghavan Edward B Stephens Sanjay V Joag Istvan Adany David M Pinson Zhuang Li Fenglan Jia Manisha Sahni Chunyang Wang Kevin Leung Larry Foresman Opendra Narayan 《Brain pathology (Zurich, Switzerland)》1997,7(3):851-861
We recently reported that a chimeric simian/human immunodeficiency virus (SHIVKU-1 ) developed in our laboratory caused progressive depletion of CD4+ T lymphocytes and AIDS within 6 months of inoculation into pig-tailed macaques (M.nemestrina). None of the pig-tailed macaques showed productive SHIV infection in the central nervous system (CNS). In this report, we show that by further passage of the pathogenic virus in rhesus macaques [M. mulatta], we have derived a new strain of SHIV (SHIVKU-2 ) that has caused AIDS and productive CNS infection in 3 of 5 rhesus macaques infected with the virus. Productive replication of SHIV in the CNS was clearly shown by high infectivity titers and p27 protein levels in brain homogenates, and in 2 of the 3 rhesus macaques this was associated with disseminated, nodular, demyelinating lesions, including focal multinucleated giant cell reaction, largely confined to the white matter. These findings were reminiscent of HIV-1 associated neurological disease, and our immunohistochemical and in situ hybridization data indicated that the neuropathological lesions were associated with the presence of SHIV-specific viral antigens and nucleic acid respectively. However, the concomitant reactivation of opportunistic infections in these macaques suggested that such pathogens may have influenced the replication of SHIV in the CNS, or modified the neuropathological sequelae of SHIV infection in the rhesus species, but not in pig-tailed macaques. Our findings in the two species of macaques highlight the complexities of lentiviral neuropathogenesis, the precise mechanisms of which are still elusive. 相似文献
25.
The 44-amino-acid E5 oncoprotein of bovine papillomavirus type 1 transforms immortalized murine fibroblast cell lines. This highly hydrophobic protein forms homodimers, localizes to intracellular membrane compartments (including the Golgi apparatus), and forms a complex with the 16-kDa membrane-embedded constituent (16k) of the vacuolar proton-ATPase. To develop a system for the genetic and biochemical analysis of the E5/16k interaction, the E5 gene was cloned into a new vector which was designed for expression in the fission yeast Schizosaccharomyces pombe. The E5 protein synthesized in this system dimerized normally and bound to endogenous and overexpressed S. pombe 16k protein. Comparison of the S. pombe and mammalian 16k proteins showed strong conservation in carboxyl-terminal amino acids but greater variation in the amino-terminal sequences, suggesting that E5 was interacting with the 16k carboxyl domains. Finally, a new protein epitope tag is described which permitted for the first time the coprecipitation of E5 with antibodies directed against the 16k protein. 相似文献
26.
27.
Ravi Kaul V.K. Bajpai A.C. Shipstone Hari K. Kaul C.R. Krishna Murti 《Experimental and molecular pathology》1981,34(3):290-298
The kinetics of bilirubin erythrocyte interaction have been followed by scanning electron microscopy. Bilirubin-induced erythrocyte cytotoxicity embodies the interaction of the bile pigment with the outer half of the erythrocyte plasma membrane bilayer couple. This interaction leads to crenation. This membrane event appears to be primary and precedes hemolysis. The membrane crenation is dependent on the concentration of the bile pigment and is reversed by bovine serum albumin again in a concentration-dependent manner. Phospholipids do not alter bilirubin erythrocyte ineraction. Erythrocytes from jaundiced neonates show crenated surface structure in scanning electron microscopy. The crenation depends upon severity of jaundice in neonates. This suggests similarity between in vivo and in vitro mechanisms of cytotoxicity mediated by the bile pigment. Further, phototherapy reverses the process of membrane crenation. The in vivo photocatabolities isolated from urine of jaundiced neonates are nontoxic to erythrocyte membrane. 相似文献
28.
Immediate breast reconstruction-impact on radiation management 总被引:1,自引:0,他引:1
Shankar RA Nibhanupudy JR Sridhar R Ashton C Goldson AL 《Journal of the National Medical Association》2003,95(4):286-295
Breast reconstruction is an option for women undergoing modified radical mastectomy due to a diagnosis of breast cancer. In certain patients, breast reconstruction is performed by insertion of a temporary tissue expander prior to the placement of permanent breast implants. Some of these patients, following mastectomy, may require chest wall irradiation to prevent loco regional relapse. The compatibility of radiation and tissue expanders placed in the chest wall is of major concern to the radiation oncologist. Clinically undetectable changes can occur in the tissue expander during the course of radiation therapy. This can lead to radiation treatment set-up changes, variation in tissue expansion resulting in unwanted cosmesis, and deviation from the prescribed radiation dose leading to over and/or under dosing of tumor burden. At Howard University hospital, a CT scan was utilized to evaluate the status of the temporary tissue expander during radiation treatment to enable us to prevent radiation treatment related complications resulting from dosimetric discrepancies. CT images of the tissue expander were obtained through the course of treatment. To avoid a 'geographic miss' the amount of fluid injected into the tissue expander was kept constant following patient's satisfaction with the size of the breast mound. The CT scans allowed better visualization of the prosthesis and its relation to the surrounding tumor bed. This technique ensured that anatomical changes occurring during radiation treatment, if any, were minimized. Repeated dosimetry evaluations showed no changes to the prescribed dose distribution. A CT of the reconstructed breast provides an important quality control. Further studies with greater number of patients are required for confirming this impact on radiation treatment. 相似文献
29.
Ante mortem diagnosis of human rabies using saliva samples: comparison of real time and conventional RT-PCR techniques. 总被引:1,自引:0,他引:1
T Nagaraj Joel P Vasanth Anita Desai Anupa Kamat S N Madhusudana V Ravi 《Journal of clinical virology》2006,36(1):17-23
BACKGROUND: Rabies is an enzootic and fatal disease and is still a major problem in developing countries. Ante mortem diagnosis in human cases is necessary for medical management of the patient and to ensure appropriate post-exposure treatment of contacts. Both conventional RT-PCR and Real time PCR (TaqMan) have been described for the detection of rabies virus RNA from saliva and tissue respectively, however to date, there have been no studies comparing conventional and real time PCR assays for detection of rabies virus nucleic acid using saliva samples for ante mortem diagnosis. OBJECTIVES: In this study, we evaluated the utility of conventional RT-PCR and SYBR Green I Real time PCR in the ante mortem diagnosis of rabies using saliva samples. STUDY DESIGN: Saliva samples collected from twenty-four patients presenting with typical clinical manifestations of rabies were tested in the two assays. RESULTS: Amongst the 24 samples tested, 21 samples (87.5%) were positive by either of the two molecular methods. Of these 21, rabies virus RNA was detected in 6/21 in the conventional RT-PCR assay while SYBR Green I Real time PCR could detect RNA in 18/21 samples. CONCLUSION: Real time PCR assay was more sensitive than conventional RT-PCR assay (sensitivity 75% versus 37%, p=0.0189). This study highlights the utility of molecular diagnostic tests in establishing ante mortem diagnosis of rabies using saliva samples within a few hours. 相似文献
30.
Rohini Srivastava Sonali Ray Meenakshi Sharma Nitin Sahai Ravi P. Tewari Basant Kumar 《Journal of medical engineering & technology》2020,44(7):423-430
Abstract This paper presents the hardware implementation of low delay, power-efficient, rate-adaptive dual-chamber pacemaker (RDPM) using a piezoelectric sensor. Rate adaptive pacemaker has the ability to sense the patient’s activity by means of some special sensors and it controls the pacing rate according to the patient’s activity. Ideally, there should be no delay between sensing and the subsequent pacing operation performed by the pacemaker. However, delay in the responses of various components in the circuitry produces an accumulative delay effect in any practical circuit. Physical activity and the physiological needs of the patient can be easily adapted by the rate-responsive pacemakers using a wide range of sensor information. The piezo-electric sensor recognises the pressure on human muscles because of physical activity and converts it to an electrical signal, which is received by the pulse generator of the pacemaker. When the patient is in the rest mode, the heart rate is the only parameter that is to be detected by the pacemaker. Thus, the heart rate and the physical activity both are the inevitable parameters for the design of RDPM. Performance analysis of the proposed RDPM shows a significant reduction in the delay between sensing and pacing. Device utility analysis shows that the proposed design not only requires lesser memory but also reduces the number of components on the chip. Therefore, it becomes very clear that the proposed pacemaker design will consume much lesser power. 相似文献