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排序方式: 共有1621条查询结果,搜索用时 15 毫秒
101.
102.
Expression of hepatocyte growth factor/scatter factor, its activator, inhibitors and the c-Met receptor in human cancer cells 总被引:7,自引:0,他引:7
Hepatocyte growth factor/scatter factor (HGF/SF), a cytokine associated with cancer cell migration and invasion, is synthesised as pro-HGF/SF and requires activation by factors such as the HGF activator (HGFA). The present study examined the expression of HGF/SF, HGFA, the two inhibitors to HGFA action known as hepatocyte growth factor activator inhibitors type 1 and 2 (HAI-1 and HAI-2), and the HGF/SF receptor, c-Met. We examined a variety of normal and cancer cells, which included breast, prostate, colon, bladder, liver, lung, and pancreatic cancer cell lines. The cell lines all displayed different patterns of expression, and in some of the cancer cell lines the concomitant expression of the HGF/SF, c-Met, HGFA and HAI genes was observed. The only cell line to produce a significant amount of HGF/SF was the human fibroblasts (MRC-5) which also co-expressed the c-Met and HGFA genes to allow autocrine regulation of HGF/SF stimulation, and importantly displayed little or no inhibitor presence to suppress the biological function of HGF/SF. The highly invasive breast cancer cells (MDA MB-231) expressed large amounts of both c-Met and HGFA, to enable maximum influence from HGF/SF and did not express the HAI-1 gene at all, which suggests a shift in the activation-inhibition balance to enhance metastatic potential. In contrast, the breast cancer cells of low invasive nature (MCF-7) displayed a low level of c-Met and HGFA expression, while expressing the HAI genes to a high degree. However, there was no correlation between HAI-1 and HAI-2 expression. Interestingly, there appeared to be an inverse correlation between the degree of HGFA and HAI-1 expression, which may influence the metastatic ability of the cancer cells. This study has shown that c-Met, HGF/SF and its activator and inhibitors are expressed in different patterns in cancer cells and in normal cells. The balance between HGF/SF activation and HGFA inhibition is critical to the metastatic potential of the tumour cells, and the invasive nature of the cancer cell lines correlated to the degree of c-Met and/or HGFA presence along with HAI-1 expression. 相似文献
103.
Jeremy R Parr Alex L Green Carole Joint Morag Andrew Ralph P Gregory Richard B Scott Michael A McShane Tipu Z Aziz 《Archives of disease in childhood》2007,92(8):708-711
BACKGROUND: Early onset idiopathic generalised dystonia is a progressive and profoundly disabling condition. Medical treatment may ameliorate symptoms. However, many children have profound, intractable disability including the loss of ambulation and speech, and difficulties with feeding. Following the failure of medical management, deep brain stimulation (DBS) of the globus pallidus internus (GPi) has emerged as an alternative treatment for the disorder. METHODS: We describe four children who presented with dystonia. RESULTS: Following the failure of a range of medical therapies, DBS systems were implanted in the GPi in an attempt to ameliorate the children's disabilities. All children found dystonic movements to be less disabling following surgery. Compared with preoperative Burke, Fahn and Marsden Dystonia Rating Scale scores, postoperative scores at 6 months were improved. CONCLUSIONS: DBS is effective in improving symptoms and function in children with idiopathic dystonia refractory to medical treatment. Whilst surgery is complex and can be associated with intraoperative and postoperative complications, this intervention should be considered following the failure of medical therapy. 相似文献
104.
DANA M. BAKHEET K. E. H. EL TAHIR M. I. AL-SAYED H. A. EL-OBEID K. A. AL-RASHOOD 《Pharmacological research》1999,39(6):463
The influence of N -ethyl- and N -benzyl-1,2-diphenyl ethanolamines (compounds E and B, respectively) was examined on the spontaneously contracting rabbit jejunum and the rat uterus together with their influence on the contractions induced by some spasmogens in the guinea-pig ileum and oxytocics and CaCl2in the pregnant rat uterus. Both E and B inhibited the spontaneous contractions of the rabbit jejunum with ID50values of 0.13 and 0.03 μmol ml−1. Their inhibitory activities were not antagonized by α- or β-adrenoceptor blockers but significantly reversed by CaCl2(0.015 μmol ml−1). The compounds also antagonized nicotine, ACh-, histamine-, 5-HT- and CaCl2-induced contractions by 44–100%. Compound E seemed to be several times more potent than B in inhibiting the spontaneous uterine contractions with an ID50of (7 nmol ml−1). Their inhibitory effects were not antagonized by β2-adrenoceptor or H2-receptor blocking drugs. Both compounds (40 nmol ml−1) antagonized in a competitive manner CaCl2-induced contractions in the K+-depolarised uterus and PGE2and oxytocin-induced uterine contractions. The ID50values were in the range of 1.6–10.7 nmol ml−1. The results suggest that E and B compounds may be considered as putative L-Ca2+channel blockers with certain selectivities. The E compound seemed to be more selective against uterine L-Ca2+channels and the B compound against intestinal smooth muscles. Thus, the compounds may be of potential value in treatment of some colics, the irritant bowel syndrome, dysmenorrhoea and premature deliveries. 1999 Academic Press@p$hr 相似文献
105.
Mediastinal masses: alternative approaches to CT-guided needle biopsy 总被引:10,自引:1,他引:10
106.
Williamson MR; Boyd CM; McGuire EL; Angtuaco T; Westbrook KC; Lang NP; Alston J; Broadwater JR; Navab F; Bersey ML 《Radiology》1986,159(1):272-273
The nuclear medicine bleeding scan is frequently insufficient to locate sites of bleeding precisely, in spite of its great sensitivity. A small, hand-held Geiger-Müller counter, placed directly on exposed intestine in the operating room, enables precise location of the probable bleeding site. In three patients, the technique allowed a minimal amount of intestine to be resected, distinguished between large- and small-intestinal hemorrhage, and eliminated other foci as sites of bleeding. 相似文献
107.
Boumsell L; Bernard A; Reinherz EL; Nadler LM; Ritz J; Coppin H; Richard Y; Dubertret L; Valensi F; Degos L; Lemerle J; Flandrin G; Dausset J; Schlossman SF 《Blood》1981,57(3):526-530
Tumor cells from eight adult patients with T-cell chronic malignancies were investigated with a series of monoclonal antibodies recognizing T- cell differentiation antigens. This series allowed definition of discrete subpopulations of mature T cells with functional specialization. All six patients with Sezary syndrome and one patient with T-chronic lymphocytic leukemia had cells with the same phenotype as normal helper/inducer T cells, whereas the other patient with T- chronic lymphocytic leukemia had cell with the same phenotype as normal cytotoxic/suppressor T cells. Some clinical manifestations observed in these patients may reflect retention of functional activities by their malignant cells. 相似文献
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110.
Doaa A. E. Abou‐Taleb Heba A. Abou‐Taleb Omnia El‐Badawy Asmaa O. Ahmed Alaa EL‐din Thabiet Hassan Sara M. Awad 《Dermatologic therapy》2019,32(5)
Intralesional (IL) vitamin D3 is an emerging treatment for cutaneous warts. However, its effectiveness and exact mechanism is not fully evaluated. We aimed to compare the efficacy and safety of IL purified protein derivative (PPD) and IL vitamin D3 in multiple warts and to investigate their systemic effect clinically and immunologically. Forty‐five patients with multiple extragenital warts were treated with IL‐PPD (22 patients) or IL vitamin D3 injection (23 patients) for a maximum of three sessions at 3 week intervals. Decrease in size and number of warts and adverse effects were evaluated. Serum interleukin‐12 (IL‐12) and interferon‐gamma (IFN‐γ) levels were measured before and 3 weeks after the last session. Higher clearance rates for all warts were observed with IL‐PPD compared to IL vitamin D (59.1% vs. 21.7% complete clearance, p < .001). Significant increase was found in both serum IL‐12 and IFN‐γ after PPD treatment (p = .034 and p = .04, respectively), but only IFN‐γ after vitamin D3 treatment (p = 0.02). Both IL vitamin D3 and PPD showed positive results in treatment of multiple warts. However, PPD showed higher clinical efficacy and more increase in both IL‐12 and IFN‐γ levels. 相似文献