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991.
食管癌的诊断和治疗   总被引:12,自引:8,他引:4  
1诊断 1.1普查由于食管早期癌的疗效明显好于进展期癌,加之,内镜下食管粘膜切除术用于无淋巴结转移的表浅食管癌的根治已取得良好疗效,并已逐渐被医患双方所接受,因而普查仍是目前改善食管癌(EC)疗效的肯定手段.我国北方尤其是太行山地区及伊朗里海沿岸居民、有头颈癌肿史者是EC的高发人群.  相似文献   
992.
Two genes encoding the latent membrane protein 1 (LMP1) of the Epstein-Barr virus (EBV) were isolated from a single case of Hodgkin's disease (HD) and were tested for their biological activities. The LMP1 gene from the Reed-Sternberg cells contained point mutations relative to the prototype LMP1 gene, leading to amino-acid exchanges. The LMP1 gene from passenger lymphocytes showed identical point mutations, but also had an in-frame insertion of 132 base pairs within the 33-bp repeat region. This insert encoding 44 amino acids contained the sequence PSQQS, corresponding to the potential TRAF-binding motif PXQXT/S. When compared to the B95.8 gene, both HD-derived LMP1 genes showed an increase in the transformation of Rat-1 rodent fibroblasts. The transforming ability of the LMP1 gene with the insertion was greater than that of the other HD-derived LMP1, and was comparable with the highly transforming LMP1-Cao gene derived from a nasopharyngeal carcinoma. The HD-derived genes stimulated expression of the cell-surface markers, CD40 and CD54, similarly to the LMP1-B95.8 gene, while the LMP1-Cao gene had a significantly reduced ability to induce these proteins. In contrast, the LMP1-Cao transactivated an NF-κB-response element more efficiently than did the HD-derived genes. Transfer of the 132-bp insert alone into the B95.8 gene did not increase its transforming activity to the LMP1-Cao level, indicating that additional mutations in the LMP1 gene are necessary for modulating this function. Int. J. Cancer 76:194–200, 1998.© 1998 Wiley-Liss, Inc.  相似文献   
993.
The purpose of this study was to test the comparative efficacy and toxicity of empiric gentamicin and ciprofloxacin, in combination with piperacillin, in febrile patients with treatment-induced neutropenia. Fifty patients were prospectively randomized to receive piperacillin plus gentamicin (PG), and 46 were randomized to receive piperacillin plus ciprofloxacin (PC). The groups were similar in age, sex, diagnosis, duration of neutropenia, and incidence of positive cultures. The two antibiotic regimens were associated with comparable rates of defervescence in the patients with Gram-positive bacteremia. In the patients with Gram-negative bacteremia and those with negative cultures, however, defervescence was more prompt in the PC group. In particular, 27% of the culture-negative patients on PC, compared to only 5% of those on PG, defervesced within 72 hr (P = 0.015). Because of the more prompt defervescence in the PC group, amphotericin B was used less frequently; 78% of the patients on PG compared with only 56% of those on PC were started on amphotericin B (P J Biomed Mater Res, 41, = 0.025). PC is an effective alternative to the more traditional PG for treatment of febrile neutropenic hosts who have not been given prophylactic quinolones. More important, PC appears to hasten defervescence compared with PG, especially in culture-negative patients and those with Gram-negative bacteremia, and may decrease the necessity of additional antimicrobial agents such as amphotericin B. 1998. Am. J. Hematol. 58: 293–297, 1998. © 1998 Wiley-Liss, Inc.  相似文献   
994.
Background The absence of the putative DNA/RNA helicase Schlafen11 (SLFN11) is thought to cause resistance to DNA-damaging agents (DDAs) and PARP inhibitors.Methods We developed and validated a clinically applicable SLFN11 immunohistochemistry assay and retrospectively correlated SLFN11 tumour levels to patient outcome to the standard of care therapies and olaparib maintenance.Results High SLFN11 associated with improved prognosis to the first-line treatment with DDAs platinum-plus-etoposide in SCLC patients, but was not strongly linked to paclitaxel–platinum response in ovarian cancer patients. Multivariate analysis of patients with relapsed platinum-sensitive ovarian cancer from the randomised, placebo-controlled Phase II olaparib maintenance Study19 showed SLFN11 tumour levels associated with sensitivity to olaparib. Study19 patients with high SLFN11 had a lower progression-free survival (PFS) hazard ratio compared to patients with low SLFN11, although both groups had the benefit of olaparib over placebo. Whilst caveated by small sample size, this trend was maintained for PFS, but not overall survival, when adjusting for BRCA status across the olaparib and placebo treatment groups, a key driver of PARP inhibitor sensitivity.Conclusion We provide clinical evidence supporting the role of SLFN11 as a DDA therapy selection biomarker in SCLC and highlight the need for further clinical investigation into SLFN11 as a PARP inhibitor predictive biomarker.Subject terms: Tumour biomarkers, Tumour biomarkers  相似文献   
995.
Three-dimensional (3D) coronary imaging has the potential to overcome problems resulting from vessel tortuosity and to reduce partial volume effects. With these techniques, however, acquisition times are long and respiratory motion artifacts problematical. This work describes the development of a method that applies phase encode reordering to 3D acquisitions, allowing larger navigator acceptance windows to be used, with a consequent reduction in acquisition time. This method is compared with navigator acceptance window methods (the acceptance-rejection algorithm and the diminishing variance algorithm) and the retrospective respiratory gating technique, both in vitro and in vivo. The use of phase reordering with a 10 mm acceptance window provided a significant increase in scan efficiency over a non-reordered 5 mm method (P<0.001) with no significant change in image quality, and a significant increase in image quality compared with a non-reordered image acquired in the same time (P<0.05). A significant improvement in both image quality and scan efficiency was demonstrated over the retrospective respiratory gating method (P<0.05).  相似文献   
996.
997.
BACKGROUND & METHOD: The role of multidrug resistance (MDR) was investigated in patients with relapsed chronic lymphocytic leukemia (CLL). PSC-833 was added to modified VAD (a 4-day infusion of vincristine, doxorubicin, with oral dexamethasone, every 3 weeks), in an attempt to improve the response rate (21%) in a prior study. Laboratory tests to determine MDR and apoptosis proteins were correlated with response. RESULTS: Two of the seven MDR-positive cases and one of the four MDR-negative patients achieved a partial response (no significant difference). No significant correlation with response was found in any of the laboratory tests for apoptosis. CONCLUSION: VAD plus PSC-833 had the same (21%) partial response rate as a prior ECOG study without PSC-833. No correlation of response with MDR or apoptosis testing was found. Other drug resistance factors must play a significant role in determining the response of relapsed patients with CLL.  相似文献   
998.
We have implemented the use of a small-scale, 7-vial Micro Freeze Dryer (MicroFD®; Millrock Technology, Inc.) that has the capability to accurately control heat transfer during lyophilization. We demonstrate the ability to fine-tune the MicroFD® vial heat transfer coefficient (Kv) to match the Kv of vials in a LyoStar III laboratory-scale unit. When the MicroFD® is run under conditions that match the Kv of the LyoStar III, the resulting lyophilization performance between scales results in equivalent product temperature profiles and critical quality attributes for the same drying process. The proposed workflow demonstrates how exploitation of Kv control in the MicroFD® enables cycle development of at-scale lyophilization processes using only 7 product vials. By changing the MicroFD® Kv, laboratory and, potentially, manufacturing cycles may be simulated using only 7 product vials for tremendous active pharmaceutical ingredient savings, as long as at-scale heat transfer coefficients are well characterized.  相似文献   
999.
南蛇藤素抑制豚鼠体外精子的受精能力   总被引:9,自引:0,他引:9  
南蛇藤素(Cel)对豚鼠精子前向运动(FM)、获能(Cap)、顶体反应(AR)和穿透去透明带仓鼠卵(SPA)均有明显的抑制作用,其作用强度随剂量而增加;对Cel的敏感性依次为精子Cap>FM>SPA>AR。Cel对豚鼠精子AR,FM和Cap的抑制作用比乙酸棉酚(GA)明显为强。  相似文献   
1000.
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