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101.
N Sharma J Luo D A Kirschmann Y O'Malley M E Robbins E T Akporiaye D M Lubaroff P M Heidger M J Hendrix 《Cancer research》1999,59(10):2271-2276
The Dunning R-3327 rat prostatic adenocarcinoma is a widely accepted model for in vivo experimental studies of prostate cancer. We have previously derived phenotypically distinct cell lines from a s.c. tumor resulting from the inoculation of the R-3327-5 subclone into Copenhagen rats. In this study, we report studies using a gelatin sponge model for the delivery of tumor cells and the retrieval of tumor-specific leukocytes responsive to different prostatic cell lines. S.c. preimplanted sponges were inoculated with tumor cells previously selected for differential properties of tumor formation and metastasis and examined for leukocyte content at time points of 1, 3, and 5 weeks after tumor cell inoculation. Cytospin and flow cytometric analyses revealed fewer tumor-associated leukocytes present in sponges inoculated with tumorigenic R-3327-5' and R-3327-5'B lines, with lesser sponge degradation, than in experiments with the nontumorigenic R-3327-5'A line, suggestive of a tumor cell-induced immunomodulatory mechanism. Morphological studies indicate an intermittent tumor growth pattern that gradually disappears in sponges inoculated with the nontumorigenic R-3327-5'A cells but a robust growth pattern in sponges inoculated with the tumorigenic cell lines. Cytokine analyses show the secretion of higher levels of active transforming growth factor-beta by the more invasive and metastatic lines. Total transforming growth factor-beta levels are higher in the epithelial, tumorigenic R-3327-5'B line. Additionally, the more tumorigenic lines secrete interleukin 10, a potent immunosuppressive molecule. In this report, we demonstrate the ability to retrieve viable leukocyte populations from a prostate tumor line bearing sponges, which offers an important model for further in vitro and in vivo manipulations and holds promise for testing adoptive immunotherapeutic strategies. 相似文献
102.
Characterization of a highly invasive and spontaneously metastatic human malignant melanoma cell line. 总被引:8,自引:0,他引:8
D R Welch J E Bisi B E Miller D Conaway E A Seftor K H Yohem L B Gilmore R E Seftor M Nakajima M J Hendrix 《International journal of cancer. Journal international du cancer》1991,47(2):227-237
Although the incidence of, and deaths due to, malignant melanoma are rising at a rapid rate, few experimental models mimic the highly metastatic properties associated with the pathogenesis of the human disease, making study of the disease difficult. Thus, new human models are required to understand melanoma biology, especially its metastatic properties. Here we describe C8161, a highly invasive and spontaneously metastatic human melanoma cell line, which grows progressively in the subcutis of athymic nude mice with an average doubling time of approximately 6 days. By the time the tumor reaches a diameter of 1 cm, amelanotic metastases in lymph nodes, skin, peritoneal wall, spleen and lungs have formed. By comparing C8161 to variants from other well-characterized human malignant melanomas (A375 and MeWo) with differing metastatic traits, properties presumed to be involved in metastatic propensity were examined. C8161 showed a 2- to 14-fold higher ability to invade reconstituted basement membrane barriers in the MICS and correspondingly high type-IV collagenase mRNA levels and collagenolytic activity, as compared with other melanoma cell lines. Likewise, differential adhesion to immobilized RBM or HUVEC monolayers was observed, but did not correlate to rank orders of malignant properties. Recently, a correlation between surface expression of ICAM-1 and secondary tumor formation by human melanomas has been described in several laboratories. Basal levels of ICAM-1 on C8161, A375 and MeWo human melanomas were compared, but no correlation with metastatic potential was noted. Proto-oncogene expression in C8161 cells was compared with A375P and A375M variants using Northern blot analysis. c-myc expression was 6-fold greater than both A375 variants; c-fos expression was 3.4-fold less than A375P and 1.7-fold less than A375M; c-jun in C8161 cells was 2.5-fold and 2.1-fold greater than expression in A375P and A375M, respectively. Because C8161 is so highly malignant, amenable to experimental manipulation, and its behavior in nude mice mimics the clinical course of malignant melanoma, this cell line will prove valuable for studying properties associated with human melanoma tumor progression. 相似文献
103.
In vitro assay demonstrates similar invasion profiles for B16F1 and B16F10 murine melanoma cells 总被引:1,自引:0,他引:1
The variants of the B16 murine melanoma cell line were assayed for their invasive characteristics in the membrane invasion culture system (MICS) and concomitantly tested for their ability to form lung metastases in vivo. Specifically, the B16F1 (low metastatic variant) and the B16F10 (high metastatic variant) murine melanoma cell lines were examined for their ability to invade human amniotic basement membranes (BMs) in vitro and simultaneously examined for lung colony formation in vivo. The B16F1 and B16F10 cell lines both demonstrated similar invasion profiles over 72 h with the total percent invasion through the BMs for both cell lines not exceeding 5.0%. In vivo observations reconfirmed the significant difference in the metastatic capabilities of the 2 variants. These data suggest that tumor cells with differing metastatic propensities can invade an amniotic BM at similar rates, but their survival and metastatic lesion forming capabilities in vivo may vary considerably. 相似文献
104.
J. A. Cauley N. S. Wampler J. M. Barnhart L. Wu M. Allison Z. Chen S. Hendrix J. Robbins R. D. Jackson 《Osteoporosis international》2008,19(12):1717-1723
Summary To compare the absolute risk of fracture to the risk of other conditions by race/ethnicity, we studied 83,724 women, aged
70–79. The projected number of fractures was similar to or exceeded the combined number of cardiovascular events and breast
cancers. Osteoporosis prevention efforts should target women of all ethnicities.
Introduction The relative risk of fracture is lower in non-white compared to white women but the absolute risk of fracture in comparison to other common chronic conditions is uncertain.
Methods We performed a prospective cohort study of 83,724 women, age 50–79 years. Cardiovascular disease (CVD), invasive breast cancer
and all fractures were identified over an average of 7.7 ± 2.6 years.
Results The incidence of fracture, breast cancer, stroke and CVD varied across ethnicity. The annualized (%) incidence of fracture
was greatest in whites (2.4%) and American Indians (2.8%) and lowest among blacks (1.3%). The majority of hip fractures occurred
in white women. The projected number of women who will experience a fracture in one year exceeded the combined number of women
who would experience invasive breast cancer or a broad category of CVD events in all ethnic groups except blacks. In 10,000
black women, an estimated 153 women would experience CVD, and 35 women, breast cancer compared to 126 women expected to fracture
in one year.
Conclusion The annual risk of suffering a fracture is substantial in women of all ethnicities. Osteoporosis prevention efforts should
target all women irrespective of their race/ethnic backgrounds.
This article is discussed in an editorial that is available at . 相似文献
105.
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108.
Thirty-one bone marrow aspirations were performed on patients with prostatic carcinoma metastatic to bone. After separation over a Ficoll-Hypaque gradient viable nucleated cells were cultured in semisolid agar. Colony formation occurred in 14 of 27 (52%) nonbacterially contaminated cultures. Characterization of cells from the colonies showed them to be consistent with malignant prostate cells. After staining, these cells were periodic acid-Schiff positive, prostatic acid phosphatase positive, and prostatic specific antigen positive. Other studies demonstrated the cells to be karyotypically abnormal, ultrastructurally similar to epithelial cells, and capable of secondary colony formation. Three bone marrow aspirate specimens did not have metastatic prostatic carcinoma detected by standard methods but did demonstrate colony formation. However, colony formation was most frequently seen when a radionuclide scan was positive at the aspiration site and when tumor cells were microscopically detectable by Wright staining of a smeared aspirate. The potential utility of colony forming cultures in prostate cancer is discussed. In working with bone marrow aspirates, additional cell separation procedures may be required to calculate and maximize plating efficiencies. 相似文献
109.
110.