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141.
Sakineh‐Khatoun SHARIF Shahin EGHBAL Farhad GHARIBDOOST Mahmood A. Kbarian Farhad SHAHRAM Abdolhadi NADJI Ahmad‐Reza JAMSHIDI Fereydoun DAVATCHI 《International journal of rheumatic diseases》2007,10(2):121-124
Aim: To determine the frequency of anti‐cyclic citrullinated peptide antibody (anti‐CCP) in a group of patients with rheumatoid arthritis and another group with other rheumatic diseases. Patients and methods: Anti‐CCP1 and rheumatoid factor (RF) titres were determined in 320 serum samples; 136 from RA patients, 184 from control patients (165 patients with rheumatic diseases other than RA, and 21 patients with lymphoproliferative diseases). Results: The sensitivity of Anti‐CCP was 62.5% (95% CI: 53–70%) for the diagnosis of RA with a specificity of 89.1% (95% CI: 83–93%). The sensitivity of RF was 85.3% (95% CI: 79–91%). The specificity was 64.7% (95% CI: 57–71%). Conclusions: Anti‐CCP1 has not very high specificity for RA regarding other rheumatic disease. However it is still very helpful for the diagnosis of RA. 相似文献
142.
The vascular endothelial growth factor receptor (VEGFR-1) supports growth and survival of human breast carcinoma 总被引:8,自引:0,他引:8
Wu Y Hooper AT Zhong Z Witte L Bohlen P Rafii S Hicklin DJ 《International journal of cancer. Journal international du cancer》2006,119(7):1519-1529
Vascular endothelial growth factor receptor 1 (VEGFR-1) is present on endothelial cells and subsets of human tumor cells, raising the hypothesis that angiogenic factors may promote tumor growth both by inducing angiogenesis and directly signaling through activation of VEGFR-1 on tumor cells. Here, we report that VEGFR-1 is expressed on a panel of 16 human breast tumor cell lines, and the vasculature and the tumor cell compartment of a subset of breast carcinoma lesions, and that selective signaling through VEGFR-1 on breast cancer cells supports tumor growth through downstream activation of the p44/42 mitogen-activated protein kinase (MAPK) or Akt pathways. Ligand-stimulated proliferation of breast tumor cells was inhibited by specific blockade with an anti-VEGFR-1 neutralizing monoclonal antibody. Treatment with anti-VEGFR-1 mAb significantly suppressed the growth of DU4475, MCF-7, BT-474 and MDA-MB-231 breast xenografts in athymic mice. Histological examination of anti-VEGFR-1 mAb treated tumor xenografts showed a significant reduction of activation of the p44/42 MAPK or Akt pathways in tumor cells resulting in an increase in tumor cell apoptosis. Importantly, cotreatment with mAbs targeting human VEGFR-1 on tumor cells and murine VEGFR-1 on vasculature led to more potent growth inhibition of breast tumor xenografts. The results suggest that VEGF receptors may not only modulate angiogenesis, but also directly influence the growth of VEGF receptor expressing tumors. 相似文献
143.
G M Bahr J L Stanford T D Chugh M A Shaaban M Gabriel B al-Shimali Z Siddiqui F Ghardani G A Rook A Shahin 《Tubercle》1990,71(2):77-86
Sixty-five patients, many of them immigrant to Kuwait, with bacteriologically proven, adult type, pulmonary tuberculosis were studied by many parameters over the 4 months following diagnosis. Twelve were infected with tubercle bacilli resistant to at least one anti-tuberculosis drug. Preliminary evidence suggested that this was frequently primary resistance in patients infected in their countries of origin. The Kuwaiti environment results in very high skin test and lymphocyte proliferative responses (LTT) to shared and species specific antigens of mycobacteria in healthy persons. In comparison, patients with tuberculosis lacked cellular responses to group i and group ii antigens, but had increased IgG and IgA binding to mycobacterial antigens in general. LTT responses to added interleukin 2, and production of alpha interferon, were normal in our patients, but induction of gamma interferon in response to phytohaemagglutinin was reduced initially, rising towards normal during treatment. Biochemical and haematological abnormalities present at the time of diagnosis rapidly corrected. The disease differed from that reported in most previous studies in that fever was uncommon, the disease was never fatal, and most tuberculin tests were not necrotising. This implied that a detrimental immunopathological component is less pronounced in those exposed to the Kuwaiti environment, and a hypothesis is put forward to explain this. 相似文献
144.
Blebea J Volteas N Neumyer M Ingraham J Dawson K Assadnia S Anderson KM Atnip RG 《Annals of vascular surgery》2002,16(1):77-83
Duplex ultrasound of the visceral arteries is a technically challenging procedure. We examined the clinical usefulness of
perflutren intravenous ultrasound contrast to improve the diagnostic accuracy of such studies. Seventeen patients were prospectively
studied. A color duplex imaging study of the visceral vasculature was performed with and without the contrast agent. Vessels
were imaged and peak systolic velocity and Doppler waveforms of the aorta, celiac artery, superior mesenteric artery, and
the inferior mesenteric artery were examined. These results were independently compared to those of contrast angiography.
From this analysis we concluded contrast-enhanced duplex imaging of the mesenteric arteries is safe but not routinely required
when performed by an experienced sonographer. Ultrasound contrast may be helpful in difficult patients when the vessels are
not initially successfully visualized. 相似文献
145.
Internal tandem duplication of the FLT3 gene (FLT3/ITD) has been linked to a poor outcome in acute myeloid leukemia (AML). However, the prognostic value of FLT3/ITD in various cytogenetic risk groups is still a matter of debate. The aim of this study was to evaluate the prognostic significance of FLT3/ITD in patients with de novo AML and normal cytogenetics (NC-AML). Diagnostic samples of 39 patients were investigated by PCR of exons 14 and 15 of the FLT3 gene in patients with AML. Subgroups included 26 patients with normal cytogenetics, 8 patients with t(15;17), 4 patients with t(8;21), and 1 patient with inv (16). FLT3/ITD was found in 6/39 (15.4%) AML cases. By cytogenetic subgroups, there were 4/6 normal cytogenetics, 1/6 t(15;17) and 1/6 t(8;21) positive patients. Patients were M1, 3/13; M2, 2/12; M3, 1/9; M4, 0/4; and M5, 0/1. The patients were followed up for a mean of 34.5 ± 2.3 months. The complete remission rates for the FLT3/ITD+ and FLT/ITD? groups were 50% vs 63.6% in normal cytogenetics, while the relapse rates were 50% vs 28.6% in normal cytogenetics. Interestingly, disease-free survival (DFS) at 3?years was significantly different in patients with normal cytogenetics: DFS was 5% in patients with FLT3/ITD+ vs 30% of patients with FLT3/ITD? (P?=?0.001). Although based on a study with a limited number of AML patients, our data suggest a high prognostic value of FLT3/ITD in patients with normal/favorable cytogenetics. Further study on a larger scale is recommended. 相似文献
146.
Beate Heissig Yuichi Ohki Yayoi Sato Shahin Rafii Zena Werb Koichi Hattori 《Hematology (Amsterdam, Netherlands)》2013,18(3):247-253
Stem cells reside in a physical niche, a particular microenvironment. The organization of cellular niches has been shown to play a key role in regulating normal stem cell differentiation, maintenance and regeneration. Hematopoietic stem cells (HSC) emerge at distinct allocation territories during ontogenesis, notably the aorto-gonadal region, the fetal liver. Adult HSC expand and differentiate exclusively in the bone marrow (BM). They can be mobilized into the blood stream. This implies that stem cells are not autonomous units of development; rather, tissue specific niches control their destiny. Interaction of HSCs with their stem cell niches is critical for adult hematopoiesis in the BM. A niche is composed of stromal cells, which either through direct cell-to-cell contact or via release of soluble factors maintain the typical features of stem cells, mainly stem cell quiescence, maintenance or expansion. HSCs are keeping the balance of the quiescence and the self-renewal in the stem cell niche, and are maintaining long-term hematopoiesis. Therefore, an understanding of cellular and chemical architecture of the stem cell niche is vital in understanding stem cell behavior. This review summarizes the recent developments in our understanding of the stem cell niche with particular focus on the HSC niche. 相似文献
147.
Kaelo K. Seatla Dorcas Maruapula Wonderful T. Choga Tshenolo Ntsipe Nametso Mathiba Mompati Mogwele Max Kapanda Bornapate Nkomo Dinah Ramaabya Joseph Makhema Mompati Mmalane Madisa Mine Ishmael Kasvosve Shahin Lockman Sikhulile Moyo Simani Gaseitsiwe 《Viruses》2021,13(4)
There are limited real-world mutational and virological outcomes data of treatment-experienced persons diagnosed with HIV-1 subtype C (HIV-1 C) who are failing Integrase Strand Transfer Inhibitor-based regimens. Requisition forms sent for HIV-1 genotypic resistance testing (GRT) between May 2015 and September 2019 were reviewed and participants experiencing virologic failure while on dolutegravir (DTG) or raltegravir (RAL) cART at sampling recruited. Sanger sequencing of the HIV-1 Pol gene was performed from residual plasma samples and drug resistance mutational (DRM) analysis performed using the Stanford University HIV drug resistance database. 40 HIV-1C integrase sequences were generated from 34 individuals, 24 of whom were on DTG cART, three on RAL cART and seven on an unknown (DTG or RAL)-anchored cART at time of GRT. 11/34 (32%) individuals had DRMs to DTG and other integrase inhibitors. 7/11 (64%) patients had exposure to a RAL-based cART at the time of sampling. Out of the 11 individuals with DRMs, one (9%) had 2-class, 6 (55%) had 3-class, and 4 (36%) had 4-class multidrug-resistant HIV-1C. 7/11 individuals (64%) are currently virologically suppressed. Of the four individuals not virologically suppressed, three had extensive DRMs involving 4-classes of ARV drugs and one individual has demised. Resistance to DTG occurs more often in patients exposed to RAL cART. Individuals with 4-class DRMs plus integrase T97 and E157Q mutations appear to have worse outcomes. There is a need for frequent VL monitoring and GRT amongst treatment-experienced HIV-1C diagnosed individuals. 相似文献
148.
Detection of methylated apoptosis-associated genes in urine sediments of bladder cancer patients. 总被引:11,自引:0,他引:11
Martin G Friedrich Daniel J Weisenberger Jonathan C Cheng Shahin Chandrasoma Kimberly D Siegmund Mark L Gonzalgo Marieta I Toma Hartwig Huland Christine Yoo Yvonne C Tsai Peter W Nichols Bernard H Bochner Peter A Jones Gangning Liang 《Clinical cancer research》2004,10(22):7457-7465
PURPOSE: There is increasing evidence for a fundamental role for epigenetic silencing of apoptotic pathways in cancer. Changes in DNA methylation can be detected with a high degree of sensitivity, so we used the MethyLight assay to determine how methylation patterns of apoptosis-associated genes change during bladder carcinogenesis and whether DNA methylation could be detected in urine sediments. EXPERIMENTAL DESIGN: We analyzed the methylation status of the 5' regions of 12 apoptosis-associated genes (ARF, FADD, TNFRSF21, BAX, LITAF, DAPK, TMS-1, BCL2, RASSF1A, TERT, TNFRSF25, and EDNRB) in 18 bladder cancer cell lines, 127 bladder cancer samples, and 37 samples of adjacent normal bladder mucosa using the quantitative MethyLight assay. We also analyzed the methylation status in urine sediments of 20 cancer-free volunteers and 37 bladder cancer patients. RESULTS: The 5' regions of DAPK, BCL2, TERT, RASSFIA, and TNFRSF25 showed significant increases in methylation levels when compared with nonmalignant adjacent tissue (P < or = 0.01). Methylation levels of BCL2 were significantly associated with tumor staging and grading (P < or = 0.01), whereas methylation levels of RASSF1A and ARF were only associated with tumor stage (P < or = 0.04), and TERT methylation and EDNRB methylation were predictors of tumor grade (P < or = 0.02). To investigate clinical usefulness for noninvasive bladder cancer detection, we further analyzed the methylation status of the markers in urine samples of patients with bladder cancer. Methylation of DAPK, BCL2, and TERT in urine sediment DNA from bladder cancer patients was detected in the majority of samples (78%), whereas they were unmethylated in the urine sediment DNA from age-matched cancer-free individuals. CONCLUSIONS: Our results indicate that methylation of the 5' region of apoptosis-associated genes is a common finding in patients with bladder carcinoma. The ability to detect methylation not only in bladder tissue, but also in urine sediments, suggests that methylation markers are promising tools for noninvasive detection of bladder cancers. Our results also indicate that some methylation markers, such as those in regions of RASSF1A and TNFRSF25, might be of limited use for detection because they are also methylated in normal bladder tissues. 相似文献
149.
Analysis of protective and nonprotective monoclonal antibodies specific for Bordetella pertussis lipooligosaccharide. 总被引:2,自引:2,他引:0 下载免费PDF全文
In this study, it has been determined that immunoglobulin G1 (IgG1) and IgG3 monoclonal antibodies directed to the lipooligosaccharide A of Bordetella pertussis were able to protect mice from fatal aerosol infection. No correlation was found between the bactericidal activity in vitro in the presence of complement and the protection in mice, since a bactericidal IgG3 did not elicit protection. In addition, no significant difference in protective capacity was observed with bactericidal and nonbactericidal IgG1 antibodies, indicating that bactericidal activity is not a requirement for protection mediated by certain anti-lipooligosaccharide A antibodies. A reduction in protection in C5-deficient mice was observed, suggesting a significant role for complement in certain host defense mechanisms against B. pertussis infection. 相似文献
150.
Soltani AE Moharari RS Ghaffari R Zahedi H Hajmahmoodi M 《Saudi medical journal》2007,28(9):1446-1448
Fucosidosis is a rare, autosomal recessive lysosomal storage disorder caused by a severe deficiency of a-L-fucosidase. Patients usually have some problems with glycoprotein storage in the brain and other organs, and some structural abnormalities that need special consideration in anesthesia. It has 2 types, the early onset or infantile, and the juvenile. Here we present an 8-year old girl with deformities in the maxillofacial region, with big tongue, small and retracted chin, saddle nose, and short neck that could not be extended, causing difficult intubation, and congenital cardiac problems requiring a special anesthetic strategy. 相似文献