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1.
Mammary fibroblast influence on normal mouse mammary epithelial cell responses to estrogen in vitro 总被引:7,自引:0,他引:7
S Z Haslam 《Cancer research》1986,46(1):310-316
Estrogen-dependent stimulation of progesterone receptor (PgR) concentration or cell proliferation of normal mammary epithelial cells in vitro has been shown to be associated with the presence of mammary fibroblasts. To investigate further the nature of fibroblast influence on epithelial cells, Percoll-purified epithelial cells from collagenase-dissociated mammary glands of mid-pregnant BALB/c mice were co-cultured with mammary fibroblasts that were either untreated, irradiated, or glutaraldehyde-killed or with fibroblast-conditioned medium. Epithelial cells were then assayed for either estrogen-dependent stimulation of PgR by measuring specific [3H]R5020 binding or for estrogen-dependent stimulation of DNA synthesis by [3H]thymidine autoradiography. The results demonstrate that stimulation of PgR does not require the presence of live fibroblasts; either glutaraldehyde-killed fibroblasts or conditioned medium was effective. Pretreatment of culture dishes with type I collagen was equally effective, indicating that fibroblasts may promote the PgR response via a substratum effect. In distinct contrast, estrogen-dependent stimulation of DNA synthesis occurred only when live fibroblasts were present in high numbers and/or in direct contact with epithelial cells. Furthermore, under these latter conditions, epithelial cells also promoted estrogen-dependent stimulation of fibroblast DNA synthesis. Differences in both epithelial and fibroblast cell morphologies were also observed under co-culture conditions, which suggested that cell-cell communication or another interactive phenomenon takes place and is bidirectional. Thus there appear to be at least two different mechanisms by which fibroblasts can influence two specific responses of epithelial cells to estrogen. The present results demonstrate that the specific nature of epithelial-stromal interactions can determine and modulate epithelial cell responses to estrogen and may reflect in vivo regulatory processes affecting normal and neoplastic mammary cells. 相似文献
2.
Lipoprotein macroaggregates in bronchoalveolar lavage fluid from patients with diffuse interstitial lung disease: comparison with idiopathic alveolar lipoproteinosis.
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Lipoprotein macroaggregates were present in cytocentrifuge preparations of bronchoalveolar lavage fluid from four patients with diffuse lung diseases other than idiopathic alveolar lipoproteinosis. In three patients the primary diagnosis was cryptogenic fibrosing alveolitis and in one sarcoidosis. We confirmed the presence of large multilamellar aggregates of lipoprotein by ultrastructural examination in patients with both interstitial lung disease and idiopathic alveolar lipoproteinosis. The small lamellar bodies and amorphous debris found in idiopathic alveolar lipoproteinosis were rare in the patients with interstitial lung disease. The lavage fluid from patient with interstitial lung disease did not show the substantial alterations in phospholipid composition that were seen in lavage fluid in idiopathic alveolar lipoproteinosis. These ultrastructural and biochemical features may help to distinguish idiopathic from other causes of alveolar lipoproteinosis, particularly at an early stage, when differential diagnosis may be difficult. 相似文献
3.
进一步研究了抗三尖杉酯碱的HL-60细胞(HR20)抗细胞凋亡的机制及该抗性和抗药性的关系。结果表明,环孢菌素A(CsA)20,10μg·ml ̄(-1)诱导HL-60细胞发生凋亡,而阻断HR20细胞于G_1期,就不能诱导细胞发生凋亡。低浓度的CsA明显增加柔红霉素在HR20细胞内的积聚,其逆转抗药性作用与阻断细胞周期运行无关。CsA10μg·ml ̄(-1)处理HR20细胞,可引起50kDa的蛋白质高度磷酸化。结果提示:环孢菌素A阻断抗三尖杉酯碱的HL-60细胞于G_1期,而诱导敏感的HL-60细胞发生凋亡,其阻断作用与抗药性无关 相似文献
4.
Hydrolysis of peptides within lumen of small intestine 总被引:2,自引:0,他引:2
5.
P L Haslam B Thompson I Mohammed P J Townsend M E Hodson E J Holborow M Turner-Warwick 《Clinical and experimental immunology》1979,37(3):381-390
Increased Clq binding levels have been obtained in serum from twenty-one (50%) of forty-two patients with cryptogenic fibrosing alveolitis (CFA) suggesting the presence of circulating immune complexes. There was a low frequency of positive results using a number of other tests for circulating immune complexes. The increased Clq binding levels were observed in six (35%) out of seventeen patients with lone lung involvement and in fifteen (60%) out of twenty-five patients with extrapulmonary connective tissue disorders. There was an especially close correlation between arthritis and elevated Clq binding. A strong correlation between Clq binding levels and levels of circulating rheumatoid factor (RF) and IgG, and enhancement in macrophage radiobioassay tests using RF-containing sera, suggested that RF might be involved in the circulating immune complexes in these patients. DNAase pre-treatment of sera did not influence the findings, and there was no correlation between Clq binding and levels of immunofluorescent ANA, C-reactive protein levels, or platelet counts. A weak correlation between Clq binding and erythrocyte sedimentation rates, and slightly lower binding levels in treated than untreated patients with 'lone' CFA suggested that binding levels may give some indication of disease activity and may in some instances be influenced by treatment. 相似文献
6.
7.
Summary The relationships of VII and VIII cranial nerves and related arteries are reviewed in 26 preparations by microdissection techniques. These vessels may be grouped in large (AICA, PICA), medium (LA, SA, CSA, RPI) and small calibre (vasa nervorum, radicullar and medullar branches). The importance of these structures in acoustic neuroma surgery, vestibular neurectomy and cross-compression syndromes is discussed. Vascular loops and elongated arteries are normal structures present at birth.This work was supported by a grant from the AJ Roemmers Foundation 相似文献
8.
Differential pattern of DNA-aneuploidy in human malignancies 总被引:5,自引:0,他引:5
Th Büchner W Hiddemann B Wörmann B Kleinemeier J Schumann W Göhde J Ritter K.-M Müller DB von Bassewitz A Roessner E Grundmann 《Pathology, research and practice》1985,179(3):310-317
The differential pattern of DNA-aneuploidy, detected by flow cytometry (FCM) regarding its frequency, grade and multiclonality, was investigated and correlated to tumor type, malignancy grade, tumor stage and prognosis in a multi-institutional study at the University of Münster. High resolution measurements using admixed normal blood reference cells were undertaken in 2413 cases of 13 different malignant diseases and in 776 benign lesions or samples. The incidence of DNA-aneuploidy was highest in melanomas, carcinomas, testicular tumors, sarcomas (75%-95%) and myelomas (65%). Acute leukemias showed an intermediate DNA-aneuploidy rate of 40% with special subgroups represented by common ALL (44%), p less than 0.05) and myelomonocytic/monocytic AML (47%, p less than 0.01). The lowest DNA-aneuploidy-rate was found in basal cell skin carcinomas (19%) and congenital melanocytic nevi (9%). No case of DNA-aneuploidy was observed in the 776 benign lesions or samples.--DNA-indices giving the grade of DNA-aneuploidy with 1.0 for normal diploid G1/0 cells were found distributed predominantly between 1.0 and 2.0 in the solid tumors, except testicular tumors, clustering around a triploid maximum at 1.5. DNA-indices of myelomas and acute leukemias generally ranged below 1.25 with lower DNA-aneuploidy grades in AML than in ALL (p less than 0.01).--In melanomas the aneuploidy rate was higher (86%) in metastases than in the primary tumors (54%, p = 0.001).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
9.
Shiga toxin is transported from the endoplasmic reticulum following interaction with the luminal chaperone HEDJ/ERdj3
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Shiga toxin (Stx) follows a complex intracellular pathway in order to kill susceptible cells. After binding to cell surface glycolipids, the toxin is internalized and trafficked in retrograde fashion to the endoplasmic reticulum (ER). From the ER lumen, the toxin must gain access to the cytoplasm, where it enzymatically inactivates the 28S rRNA, inhibiting protein synthesis. The host molecules involved in this pathway and the mechanisms utilized by the toxin to access the cytoplasm from the ER are largely unknown. We found that Stx is capable of energy-dependent transport across the ER lumen, as has recently been demonstrated for the cholera and ricin toxins. Genetic screening for molecules involved in Shiga toxin trafficking yielded a cDNA encoding a prematurely truncated protein. Characterization of this cDNA revealed that it encodes a novel Hsp40 chaperone, designated HEDJ or ERdj3, localized to the ER lumen, where it interacts with BiP, a molecule known to be involved in protein retrotranslocation out of the ER. We demonstrated that within the ER lumen Stx interacts with HEDJ and other chaperones known to be involved in retrotranslocation of proteins across the ER membrane. Moreover, sequential immunoprecipitation revealed that Shiga toxin was present in a complex that included HEDJ and Sec61, the translocon through which proteins are retrotranslocated to the cytoplasm. These findings suggest that HEDJ is a component of the ER quality control system and that Stx utilizes HEDJ and other ER-localized chaperones for transport from the ER lumen to the cytosol. 相似文献