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101.
OBJECTIVE: Dilute Hypaque Sodium is generally well accepted as an oral contrast agent for CT of pediatric patients who have experienced recent blunt abdominal trauma. However, Hypaque can cause complications. Using water as a substitute contrast agent eliminates these potential complications. The purpose of our study was to compare the performance of water with that of dilute Hypaque as an oral contrast agent. Our hypothesis was that we would find no significant difference in performance between the two agents in defining anatomic details of the hollow gastrointestinal tract. MATERIALS AND METHODS: We performed a retrospective review of 74 CT scans obtained in infants and children who had received blunt abdominal trauma, scoring the quality of visualization of bowel structures, the presence of non-bowel-related findings, and the confidence level in making each assessment. The date range of the scans reviewed overlapped with the period in which the oral contrast material used for scanning such patients was switched from dilute Hypaque to water. Of the 74 CT scans that we reviewed, 53 were obtained with dilute Hypaque and 21 were obtained with water. The sex distribution between the two groups was compared using a chi-square test, whereas the mean age was compared using a two-sample two-sided Student's t test. A two-sample one-sided Student's t test of equivalence was used to analyze the data. RESULTS: Sex distribution for the two groups of patients was not significantly different (69.81% of the group who received dilute Hypaque were boys; 68.18% of the group who received water were boys). Furthermore, the difference in the mean age for the two groups was not statistically significantly (dilute Hypaque group, 8.86 years; water group, 10.18 years). No statistically significant difference in performance of the contrast agents was found with respect to the detection of intraabdominal abnormality. As an oral contrast material, water performed as well as dilute Hypaque in facilitating visualization of all intraabdominal anatomic structures. CONCLUSION: In defining anatomic details of the hollow gastrointestinal tract, water is as effective as dilute Hypaque as an oral contrast agent for CT in the setting of acute blunt abdominal trauma in pediatric patients.  相似文献   
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Atypical chronic myelogenous leukemia (aCML) is a myelodysplastic/myeloproliferative disorder that usually occurs in older adults. Here we report a pediatric patient with aCML and a t(5;12)(q33;p13) with a corresponding fusion gene ETV6-PDGFRB. Because the PDGFRB tyrosine kinase is one of the known targets of tyrosine kinase inhibitors, this patient achieved cytogenetic and molecular remission with treatment with imatinib mesylate (formerly STI571; now Gleevec in the United States and Glivec in Europe). This case illustrates one of many myelodysplastic/myeloproliferative disorders that can be treated with this particular tyrosine kinase inhibitor.  相似文献   
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Normal human mammary epithelial cells (HMECs), unlike estrogen receptor-positive (ER+) breast cancers, typically express low nuclear levels of ER (ER-'poor'). We previously demonstrated that 1.0 microM tamoxifen (Tam) induced apoptosis in ER-'poor' HMECs acutely transduced with human papillomavirus-16 E6 (HMEC-E6) through a rapid mitochondrial signaling pathway. Here, we show that plasma membrane-associated E2-binding sites initiate the rapid apoptotic effects of Tam in HMEC-E6 cells through modulation of AKT activity. At equimolar concentrations, Tam and tamoxifen ethyl bromide (QTam), a membrane impermeant analog of Tam, rapidly induced apoptosis in HMEC-E6 cells associated with an even more rapid decrease in phosphorylation of AKT at serine-473. Treatment of HMEC-E6 cells with 1.0 microM QTam resulted in a 50% decrease in mitochondrial transmembrane potential, sequential activation of caspase-9 and -3, and a 90% decrease in AKT Ser-473 phosphorylation. The effects of both Tam and QTam were blocked by expression of constitutively active AKT (myristoylated AKT or AKT-Thr308Asp/Ser473Asp). These data indicate that Tam and QTam induce apoptosis in HMEC-E6 cells through a plasma membrane-activated AKT-signaling pathway that results in (1) decreased AKT phosphorylation at Ser-473, (2) mitochondrial membrane depolarization, and (3) activated caspase-9 and -3.  相似文献   
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HIV patient management requires the close interaction of clinicians and laboratorians to integrate the results obtained by emerging methodologies. Evaluation of drug susceptibility to screen for specific mutations in the HIV genome can avoid needless treatment with ineffective drugs, maximizing the benefits of costly triple-drug therapy. In addition, providing a scientific basis for the effective use of genotyping and therapeutic drug monitoring is a valuable role that laboratorians can play in optimizing patient care. The clinical utility of HIV genotyping has been defined more clearly during the last year, and pharmacokinetic profiles of the antiretrovirals are beginning to emerge in the clinical laboratory as a tool to periodically assess adherence to and efficacy of the drug regimens. However, much more work is required in this area. Switching to simpler regimens is perceived as a means to improve medication adherence, manage drug toxicity, and reduce the potential for interaction among different drugs. HIV affects the function of both cytotoxic T-cells and neutralizing antibodies. The ability to identify and quantify HIV-specific immunity may allow us to target and expand specific deficient cell clones as a means of correcting immune deficiencies and strengthening the effects of drug therapy. One such example is IL-2, shown to increase CD4 cell counts at various stages of HIV disease. Additional studies of IL-2 therapy and newer immune modulators are ongoing. Combination vaccines are being tested as a worthwhile approach to optimize induction of both CTLs and antibodies. The role of the laboratory to determine the potency of HIV vaccine candidates awaits further developments evaluating the relative importance of neutralizing and mucosal antibodies versus CTL responses and the degree of immunogenicity needed to contain the spread of infection. The Center for Disease Control and Prevention aims to reduce new HIV infections by 50% per year in the next five years, and this goal is to be achieved through selected strategies put together by the plethora of experts in this arena. The aim of this article is to update the reader on the latest trends in HIV patient management and motivate collaborations to assist in the prompt implementation of improved medical care.  相似文献   
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OBJECTIVE: This study examined the test-retest reliability of a new instrument, the Services Assessment for Children and Adolescents (SACA), for children's use of mental health services. METHODS: A cross-sectional survey was undertaken at two sites. The St. Louis site used a volunteer sample recruited from mental health clinics and local schools. The Ventura County, California, site used a double-blind, community-based sample seeded with cases of service-using children. Participating families completed the SACA and were retested within four to 14 days. The reliability of service use items was calculated with use of the kappa statistic. RESULTS: The SACA- Parent Version had excellent test-retest reliability for both lifetime service use and previous 12-month use. The SACA also had good to excellent reliability when administered to children aged 11 and older for lifetime and 12-month use. Reliability figures for children aged nine and ten years were considerably lower for lifetime and 12-month use. The younger children's responses suggested that they were confused about some questions. CONCLUSIONS: This study demonstrates that parents and older children can reliably report use of mental health services by using the SACA. The SACA can be used to collect currently unavailable information about use of mental health services.  相似文献   
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