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61.
62.
Posttransplant CD30(+) (Ki-1) anaplastic large cell lymphoma (ALCL) is rare. A review of the literature revealed only 3 such cases. All 3 cases were developed after single-organ transplantation. We describe CD30(+) (Ki-1) ALCL in a dual-organ (liver and heart) transplantation recipient. The patient was a 68-year-old white female who underwent an orthotopic heart transplantation in 1999 and a liver transplantation in 2000. She presented with nausea and was found to have CD30(+) (Ki-1) ALCL by pathologic examination of the gastric antrum biopsy specimen. To our knowledge, this patient represents the first reported case of posttransplant CD30(+) ALCL following a dual-organ transplantation.  相似文献   
63.
Controversies exist regarding the clinical presentation and characteristics of cystic fibrosis (CF) in American blacks. Between 1971 and 1986, 188 patients with CF (165 whites, 20 blacks, and 3 others) seen at Children's Hospital National Medical Center, Washington, DC, were evaluated for age at diagnosis, duration of symptoms prior to diagnosis, clinical presentations, initial sputum culture results, and weight and height at diagnosis. Comparisons between black and white patients revealed no statistically significant differences in average age at diagnosis, average duration of symptoms prior to diagnosis, average sweat electrolyte concentrations, or sputum culture results. A breakdown of presenting symptoms by race showed some points of disparity. About twice as many black patients as white patients (40% v 22%) presented with only pulmonary symptoms, whereas slightly more whites presented with only gastrointestinal symptoms (46% v 35%). Those patients presenting with a combination of symptomatology were equally distributed by race (25% black, 21% white). At diagnosis, age-adjusted weight percentiles were significantly lower for black patients than for white patients (chi 2 = 9.60, P less than or equal to 0.05). Although the authors agree that CF is relatively rare among blacks, a high index of suspicion is essential for early diagnosis.  相似文献   
64.
A Fink  G Dvir  A Miskin 《Annals of allergy》1989,62(6):499-501
A semiquantitative method (ImmunoComb) for measuring total serum IgE is described and compared with a standard radioimmunoassay (PRIST). ImmunoComb, based on a solid-phase enzyme-linked immunoassay, is self-sufficient and does not require any expensive laboratory equipment. Comparison of these two assays revealed an almost absolute agreement between them (correlation coefficient = 0.95). Furthermore, the ImmunoComb assay also demonstrated its rapidity and temperature independence while maintaining a recovery of 90% to 102%.  相似文献   
65.
INTRODUCTION: Researchers and clinicians have increasingly recognized that biological markers may help identify patients who are at risk for suicide. The objective of this retrospective, cross-sectional study was to compare the prevalence and location of white matter hyperintensities (WMH) in young inpatients with major depressive disorder (MDD) with and without histories of suicide attempts. METHODS: T2-weighted magnetic resonance images (MRI) of 102 young psychiatric inpatients with MDD were rated for the presence of WMH. Medical charts were reviewed to ascertain history of suicide attempt, demographic and clinical variables. Fisher's Exact Tests and logistic regression modeling were used to test the association between WMH and suicidality. RESULTS: Bivariate analysis showed that the prevalence of periventricular WMH was significantly higher in subjects with past suicide attempts (Fisher's Exact Test, p=0.02). Logistic regression analyses controlling for age, sex, and several clinical risk factors supported this finding (odds ratio=5.7; 95% confidence interval: 1.6, 21.2). LIMITATIONS: Due to the retrospective, cross-sectional design of our study, we are unable to determine if the WMH preceded or followed past suicide attempts. The generalizability of our findings is limited since this group of inpatients is more severely ill than the general psychiatric population. CONCLUSIONS: The increased prevalence of periventricular WMH in young adults with MDD and a history of suicide attempt, compared to similarly depressed adults without such a history, is consistent with our findings in children and youth, and suggests there might be neurobiological in addition to psychosocial risk factors for suicide.  相似文献   
66.
Developing thymocytes are selected for recognition of molecules encoded by the major histocompatibility complex, purged of self-reactive cells and committed to either the CD4 or CD8 lineage. The 1% of thymocytes that complete these tasks emigrate and join the population of peripheral lymphocytes. Whether T cell maturation is complete at the time of thymic exit has been a subject of debate. Using mice transgenic for green fluorescent protein driven by the recombination activating gene 2 promoter to identify recent thymic emigrants, we now show that T cell differentiation continues post-thymically, with progressive maturation of both surface phenotype and immune function. In addition, the relative contribution of CD4 and CD8 recent thymic emigrants was modulated as they entered the peripheral T cell pool. Thus, T cell maturation and subset contribution are both finalized in the lymphoid periphery.  相似文献   
67.
High power transcranial beam steering for ultrasonic brain therapy   总被引:3,自引:0,他引:3  
A sparse phased array is specially designed for non-invasive ultrasound transskull brain therapy. The array is made of 200 single elements corresponding to a new generation of high power transducers developed in collaboration with Imasonic (Besan?on, France). Each element has a surface of 0.5 cm2 and works at 0.9 MHz central frequency with a maximum 20 W cm(-2) intensity on the transducer surface. In order to optimize the steering capabilities of the array, several transducer distributions on a spherical surface are simulated: hexagonal, annular and quasi-random distributions. Using a quasi-random distribution significantly reduces the grating lobes. Furthermore, the simulations show the capability of the quasi-random array to electronically move the focal spot in the vicinity of the geometrical focus (up to +/- 15 mm). Based on the simulation study, the array is constructed and tested. The skull aberrations are corrected by using a time reversal mirror with amplitude correction achieved thanks to an implantable hydrophone, and a sharp focus is obtained through a human skull. Several lesions are induced in fresh liver and brain samples through human skulls, demonstrating the accuracy and the steering capabilities of the system.  相似文献   
68.
Summary For years, brown tumors have been considered to be a characteristic of primary hyperparathyroidism. However, since 1963 several reports indicate the incidence of brown tumors in patients with renal secondary hyperparathyroidism to be 1.5%–1.7%. The appearance of multiple brown tumor lesions is rather uncommon in secondary hyperparathyroidism which is also true for malabsorption as its cause. We report on a 56-year-old man presenting with pain in the bones and multiple osteolyses. A bone biopsy specimen and the laboratory examinations were indicative of secondary hyperparathyroidism caused by malabsorption most likely due to Billroth's II/I gastric resection. Thus, the patient's osteolyses represent brown tumors which have been induced by nutritional secondary hyperparathyroidism.  相似文献   
69.
The authors developed a screening instrument to detect patients in need of complex care coordination at admission to a general hospital. On the basis of a series of risk factors for care complexity, the authors constructed a short, care complexity prediction instrument (COMPRI) and assessed its qualities. The COMPRI is an easily administered screening instrument that detects patients at risk for complex care needs for whom care coordination is indicated. COMPRI's predictive power exceeds all currently available case-mix instruments.  相似文献   
70.
Convulsive therapy was introduced to psychiatric practice in 1934. It was widely hailed as an effective treatment for schizophrenia and quickly recognized as equally effective for the affective disorders. Like other somatic treatments, it was replaced by psychotropic drugs introduced in the 1950s and 1960s. But two decades later, ECT was recalled to treat pharmacotherapy-resistant cases. Avid searches to optimize seizure induction and treatment courses, to reduce risks and fears, to broaden the indications for its use, and to understand its mechanism of action followed. Unlike other medical treatments, however, these searches were severely impeded by a vigorous antipsychiatry movement among the public and within the profession. ECT is effective in the treatment of patients with major depression, delusional depression, bipolar disorder, schizophrenia, catatonia, neuroleptic malignant syndrome, and parkinsonism, and this breadth of action is both remarkable and unique. ECT is a safe treatment. No age or systemic condition bars its use. Its major limitations are the high relapse rates and the occasional profound effects on memory and recall that mar its success. Experiments to sustain its benefits with medications and with continuation ECT are underway. Its mode of action remains a mystery and this puzzle is an unappreciated challenge. The full impact of this intervention is yet to be felt.  相似文献   
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