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51.
McGrath  HE; Liang  CM; Alberico  TA; Quesenberry  PJ 《Blood》1987,70(4):1136-1142
We have previously reported that lithium chloride (LiCl) stimulates the production of granulocyte-macrophage colony-forming cells (GM-CFC), pluripotent stem cells (CFU-S), and differentiated granulocytes, macrophages and megakaryocytes in murine Dexter marrow cultures and that this effect appears to be mediated indirectly by a radioresistant adherent marrow cell. In this study we have established that exposure of murine Dexter cultures to LiCl (4 mEq/L) causes an increase of colony-forming cell megakaryocytes (CFU-meg) over 1 to 6 weeks of culture in both supernatant (188% to 611%) and stromal phases (123% to 246%). Moreover, we have shown that lithium treatment of either irradiated (1,100 rad) or unirradiated stromal cells increased production of activities stimulating formation of megakaryocyte, granulocyte, macrophage, and mixed lineage colonies and proliferation of the factor-dependent cell line, FDC-P1. This FDC-P1 stimulatory activity was completely blocked by an antibody to purified recombinant granulocyte-macrophage colony stimulating factor (rGM-CSF). The baseline or lithium-induced--stromal-derived bone marrow colony stimulating activity was partially blocked by the antibody to rGM-CSF and by an antibody to purified colony stimulating factor I (CSF-1); the two antibodies combined resulted in greater than 90% inhibition of the lithium-induced marrow stimulatory activity. In addition, radioimmunoassay (RIA) showed that although CSF-1 was detectable in supernatants of these cultures, exposure to lithium did not increase CSF-1 levels. These data indicate that Dexter stromal cells produce CSF- 1 and GM-CSF and that lithium appears to exert its stimulatory effects on in vitro myelopoiesis by inducing production of GM-CSF.  相似文献   
52.
目的探讨电解剖系统指导在房性心律失常射频导管消融中的作用和优势。方法对25例心房颤动(阵发性15例、持续性10例)在电解剖系统指导下进行重建左心房后行线性消融,7例持续性房性心动过速(右心房性4例、左心房性3例)在电解剖系统指导下重建左/右心房标测激动顺序后行消融。结果25例心房颤动均完成预定的线性消融,其中14例阵发性者在窦性心律下电学隔离成功,10例持续性和1例阵发性者在心房颤动时电学隔离成功。7例持续性房性心动过速均在消融过程中转为窦性心律。电解剖系统指导下平均手术时间心房颤动为220min,房性心动过速为86min;平均X线透视时间心房颤动为48min,房性心动过速为20min。所有患者手术过程中均无并发症。结论在电解剖系统指引下,环肺静脉电隔离治疗心房颤动安全有效;有助于设计房性心动过速消融径线,缩短手术时间,提高成功率。  相似文献   
53.
Einerhand  MP; Bakx  TA; Kukler  A; Valerio  D 《Blood》1993,81(1):254-263
An amphotropic retroviral vector, LgAL(delta Mo + PyF101) containing a human adenosine deaminase (ADA) cDNA was used to optimize procedures for the lasting genetic modification of the hematopoietic system of mice. The highest number of retrovirally infected cells in the hematopoietic tissues of long-term reconstituted mice was observed after transplantation of bone marrow (BM) cells that had been cocultured in the presence of both interleukin-1 alpha (IL-1 alpha) and IL-3. A significantly lower number was detected when IL-1 alpha was omitted from such cocultures. The yield of cells that generate spleen colony-forming cells (CFU-S) in the BM of lethally irradiated recipients (MRA-CFU-S) significantly improved on inclusion of the adherent cell fraction of cocultures in the transplant. Retroviral integration patterns in MRA-CFU-S-derived spleen colonies showed that an MRA-CFU-S can produce many CFU-S during BM regeneration. Expression of hADA was detected in the circulating white blood cells of long-term reconstituted animals, demonstrating that the LgAL(delta Mo + PyF101) vector is capable of directing the sustained expression of hADA, and in approximately 35% of the transduced MRA-CFU-S-derived spleen colonies. These results should facilitate the development of gene therapy protocols for the treatment of severe combined immunodeficiency caused by a lack of functional ADA.  相似文献   
54.
OBJECTIVE: The changing healthcare environment world-wide is leading to extensive use of per case payment systems based on diagnosis-related groups (DRG). The aim of this study was to examine the impact of application of different DRG systems used in the German healthcare system. METHODS: We retrospectively analysed 2334 clinical data sets of inpatients discharged from an academic dermatological inpatient unit in 2003. Data were regarded as providing high coding quality in compliance with the diagnosis and procedure classifications as well as coding standards. The application of the Australian AR-DRG version 4.1, the German G-DRG version 1.0, and the German G-DRG version 2004 was considered in detail. To evaluate more specific aspects, data were broken down into 11 groups based on the principle diagnosis. MAIN OUTCOME MEASURE: DRG cost weights and case mix index were used to compare coverage of inpatient dermatological services. Economic impacts were illustrated by case mix volumes and calculation of DRG payments. RESULTS: Case mix index results and the pending prospective revenues vary tremendously from the application of one or another of the DRG systems. The G-DRG version 2004 provides increased levels of case mix index that encourages, in particular, medical dermatology. CONCLUSIONS: The AR-DRG version 4.1 and the first German DRG version 1.0 appear to be less suitable to adequately cover inpatient dermatology. The G-DRG version 2004 has been greatly improved, probably due to proceeding calculation standards and DRG adjustments. The future of inpatient dermatology is subject to appropriate depiction of well-established treatment standards.  相似文献   
55.
目的分析并探讨高钠血症对重型颅脑损伤患者预后产生的影响及处理对策。方法对我院自2007年11月至2010年10月期间收治的78例重型颅脑损伤后伴高钠血症患者的临床资料做回顾性分析。78例患者按血清钠水平分为高血钠组及高血钠组。结果全部78例重型颅脑损伤患者中继发高钠血症者37例,发生高钠血症组的GCS评分为3~5分者30例,GCS评分为6~8分者7例,两组相比差异显著(P〈0.01),具有统计学意义。高钠血症患者有27例死亡,10例生存,两组的病死率相比,差异亦显著(P〈0.01),具有统计学意义。结论患者高钠血症的病情程度和GCS分值具有密切的相关性。对于高钠血症,临床工作中必须充分提高预防意识,重视其严重后果尽早采取纠正高钠血症措施,在保守治疗无效的情况下,应尽早开始血液净化治疗,改善患者的预后。  相似文献   
56.
T-gamma lymphoproliferative disease (T-gamma LPD) is a chronic disorder of mature T cells that is associated with neutropenia and autoimmune phenomena. Although the progression of the lymphoproliferation is indolent, it is often associated with a monoclonal proliferation of T- cell-type large granular lymphocytes (LGL) that manifest multiple in vitro suppressor and cytotoxic activities. We considered the possibility that the granulocytopenia or anemia might represent an autoimmune disorder mediated by the monoclonal LGL via T-cell receptor (TCR) recognition of an antigen involved in hematopoiesis. Therefore, in an effort to characterize the usage of the TCR alpha- and beta-chain genes in patients with T-gamma LPD, we cloned and sequenced TCR alpha- and beta-chain mRNAs derived from the T-cell type LGL of five patients. The five patients studied did not use a common V alpha nor a common J alpha segment. However, an unusual finding was observed in one of the patients where the occurrence of a single variable-diversity-junctional (VDJ) rearrangement of the beta chain confirmed the monoclonal origin of the LGL proliferation. In accord with this evidence for monoclonality, many of the cells studied used a common V alpha (V alpha 19.1). In contrast to this common V alpha usage, there was a marked diversity of the J alpha segments and N-region addition that were associated with the V alpha 19.1 segment. This pattern of common V alpha usage associated with different N and J alpha segments suggests an immune-mediated selection process affecting the TCR alpha chain occurring after the transformation event that established the clone. We suggest that the T-cell-type LGL malignant clone might have developed autoreactivity conferred by the selected TCR alpha chain and that this autoreactivity might be implicated in this patient's anemia.  相似文献   
57.
Urdal  DL; Brentnall  TA; Bernstein  ID; Hakomori  SI 《Blood》1983,62(5):1022-1026
1G10, a monoclonal IgM antibody that identifies a differentiation antigen on human granulocytes and a subpopulation of monocytes, was found to react specifically with glycosphingolipids bearing the Gal beta 1-4(Fuc alpha 1-3)GlcNAc hapten (X determinant). This carbohydrate determinant was found on both glycolipid and glycoprotein molecules isolated from HL-60 cells (a promyelocytic leukemia cell line). Thus, this highly conserved carbohydrate-defined determinant previously described on mouse embryonic and mouse and human carcinoma cells is also expressed as a tissue-specific differentiation antigen on normal human granulocytes.  相似文献   
58.
59.
Electromechanical Interval and Strokes After Ablations of AF . Introduction: Atrial fibrillation (AF) is associated with increased risk of embolic stroke. Catheter ablation of AF provides an effective therapy for patients with symptomatic and drug‐refractory AF. The aim of this study was to evaluate whether the atrial electromechanical interval is useful in identifying patients at risk of stroke after successful catheter ablation. Methods and Results: A total of 279 AF patients who received catheter ablation and showed no evidence of recurrences were enrolled. Electromechanical interval (PA–PDI) was determined as the time interval from the initiation of P wave deflection to the peak of mitral inflow A wave on pulse wave Doppler imaging. The PA–PDI interval was measured for each patient after the 3‐month blanking period of catheter ablation. The clinical endpoint was the occurrence of ischemic stroke. During the follow‐up of 46.5 ± 17.2 months, 6 patients suffered from ischemic strokes. Patients with strokes had higher CHA2DS2–VASc scores and longer PA–PDI intervals (138.7 ± 12.4 ms vs 161.2 ± 7.7 ms, P value < 0.001) compared to those without strokes. At a cutoff point of 150 ms identified by ROC curve, the positive and negative predictive values of the PA–PDI interval to predict stroke were 86.7% and 100%, respectively. The PA–PDI interval improved the predictive performance of the CHA2DS2–VASc score, and the area under the ROC curve increased from 0.75 to 0.85. Conclusions: Our results suggest that the PA–PDI interval is a useful tool to identify patients with high risk of stroke after successful catheter ablation of AF. (J Cardiovasc Electrophysiol, Vol. 24, pp. 375‐380, April 2013)  相似文献   
60.
本研究旨在探讨Btk抑制剂PCI-32765和蛋白酶体抑制剂bortezomib对Raji、Ramos细胞的增殖、凋亡的影响及其作用机制.PCI-32765和bortezomib单药及联合用药处理Raji和Ramos细胞后,分别运用CCK-8法及流式细胞术检测细胞的增殖与凋亡,Western blot法检测Btk、NFκB、c-IAP1、Bcl-xL、caspase-3等蛋白的表达.结果表明:①PCI-32765(0.5、1.0、2.0、3.0、4.0、5.0、6.0μmol/L)和bortezomib(10、20、30、40、50、60、80 nmol/L)处理Raji和Ramos细胞48 h,均可抑制细胞增殖,抑制率呈剂量依赖性,且两药具有协同作用;②PCI-32765(2.0μmol/L)、bortezomib(20 nmol/L)单药及联合用药处理Raji和Ramos细胞不同时间(8、12、24、36、48、72 h),均可抑制细胞存活率,抑制率呈时间依赖性,且两药具有协同作用;③PCI-32765(2μmol/L)和bortezomib(20 nmol/L)单药及联合用药处理Raji和Ramos细胞48 h,可明显促进Raji及Ramos细胞的凋亡.Raji细胞实验结果,空白对照组、PCI-32765和bonezomib单药组、联合用药组的细胞凋亡率分别为10.34±0.53%、24.26±0.91%、43.66±1.08%与74.06±0.72%,各组间有统计学差异(P<0.05);Ramos细胞实验结果,空白对照组、PCI-32765和bortezomib单药组、联合用药组的细胞凋亡率分别为15.16±1.49%、71.36±0.82%、75.32±2.36%与84.30±0.91%,各组间有统计学差异(P<0.05);④PCI-32765和bonezomib单药处理Raji、Ramos细胞后,细胞内Btk、NFκB、Bcl-xl及c-.IAP1的表达水平较对照组降低,Caspase-3的表达水平升高,两药联用后,作用增强.结论:PCI-32765和bonezomib可以协同抑制Raji与Ramos细胞的增殖,促进其凋亡,其机制可能与抑制Btk、NFκB的活性,下调Bcl-xl及c-IAP1等抗凋亡蛋白,同时上调Caspase-3等凋亡蛋白的表达而发挥作用.  相似文献   
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