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41.
42.
Severe outcomes of allogeneic and autologous blood donation: frequency and characterization 总被引:8,自引:0,他引:8
BACKGROUND: There are few published data on severe outcomes of the donation of blood for allogeneic or autologous use. It would be helpful if blood collectors could better characterize and/or predict the likelihood of significant complications of blood donation. STUDY DESIGN AND METHODS: Very severe outcome (VSO) was defined as an event requiring hospitalization. Approximately 4.1 million American Red Cross whole-blood donation records (July 1993-March 1994) were reviewed for the incidence and type of VSO. RESULTS: A total of 33 VSOs occurred for all donations. The incidence of VSOs for allogeneic donation was 1 (0.0005%) in 198,119 and that for autologous donation was 1 (0.006%) in 16,783 (p < 0.001). First-time donors were three times as likely to have a VSO. Donors > 40 years old had 87.9 percent of the VSOs, and donors > 60 years old had 48.5 percent. Vasovagal (66.7%) and anginal (12.1%) episodes were the most frequent complications, and 66.7 percent of reactions occurred at the blood collection site. The mean hospital stay was 1.9 days. CONCLUSION: VSO is an infrequent complication of all types of blood donation, but its occurrence may be associated with significant morbidity and cost. VSO is nearly 12 times as likely in autologous blood donors. 相似文献
43.
44.
D Bolognini EM Rock NL Cluny MG Cascio CL Limebeer M Duncan CG Stott FA Javid LA Parker RG Pertwee 《British journal of pharmacology》2013,168(6):1456-1470
Background and Purpose
To evaluate the ability of cannabidiolic acid (CBDA) to reduce nausea and vomiting and enhance 5-HT1A receptor activation in animal models.Experimental Approach
We investigated the effect of CBDA on (i) lithium chloride (LiCl)-induced conditioned gaping to a flavour (nausea-induced behaviour) or a context (model of anticipatory nausea) in rats; (ii) saccharin palatability in rats; (iii) motion-, LiCl- or cisplatin-induced vomiting in house musk shrews (Suncus murinus); and (iv) rat brainstem 5-HT1A receptor activation by 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) and mouse whole brain CB1 receptor activation by CP55940, using [35S]GTPγS-binding assays.Key Results
In shrews, CBDA (0.1 and/or 0.5 mg·kg−1 i.p.) reduced toxin- and motion-induced vomiting, and increased the onset latency of the first motion-induced emetic episode. In rats, CBDA (0.01 and 0.1 mg·kg−1 i.p.) suppressed LiCl- and context-induced conditioned gaping, effects that were blocked by the 5-HT1A receptor antagonist, WAY100635 (0.1 mg·kg−1 i.p.), and, at 0.01 mg·kg−1 i.p., enhanced saccharin palatability. CBDA-induced suppression of LiCl-induced conditioned gaping was unaffected by the CB1 receptor antagonist, SR141716A (1 mg·kg−1 i.p.). In vitro, CBDA (0.1–100 nM) increased the Emax of 8-OH-DPAT.Conclusions and Implications
Compared with cannabidiol, CBDA displays significantly greater potency at inhibiting vomiting in shrews and nausea in rats, and at enhancing 5-HT1A receptor activation, an action that accounts for its ability to attenuate conditioned gaping in rats. Consequently, CBDA shows promise as a treatment for nausea and vomiting, including anticipatory nausea for which no specific therapy is currently available. 相似文献45.
心房扑动患者的下腔静脉-三尖瓣环峡部和房间隔缓慢传导的电生理意义 总被引:1,自引:0,他引:1
目的 用电 解剖标测方法标测右心房 ,然后比较心房扑动 (AFL)和房室结折返性心动过速(AVNRT)患者在下腔静脉 三尖瓣环峡部 (CTI)和心房间隔部 (AS)的电冲动传导速度 ,以便确定AFL患者除了解剖结构上的异常外 ,是否伴有心房电生理方面的异常变化。方法 1 0例AFL患者 ,男性 7例 ,女性 3例 ,平均 (53± 1 0 )岁 ;1 3例AVNRT患者 ,男性 5例 ,女性 8例 ,平均 (51± 1 1 )岁。对这两组患者进行了详细的电 解剖标测、电生理检查和射频消融术。分别以周长为 60 0、40 0、和 30 0ms在冠状静脉窦 (CS)起搏的情况下测量AFL和AVNRT患者的CTI和AS的冲动传导速度 ,并将两组患者在CTI和AS的冲动传导速度进行比较。结果 与AVNRT患者相比 ,AFL患者在各个起搏周长 (PCL)时CTI和AS的冲动传导速度都明显减慢 (P <0 0 5)。另外 ,在AFL组 ,AS的冲动传导速度在起搏周长 60 0、40 0ms时低于CTI,但在 30 0ms时差异无显著性 (P >0 0 5)。因为在AFL组 ,PCL为 30 0ms时的冲动传导速度明显低于 60 0和 40 0ms时的冲动传导速度 ,致使PCL为 30 0ms时CTI和AS的冲动传导速度差异无显著性。结论 与CTI相比 ,AS的冲动传导速度在所有患者都较慢 ,而AFL患者在CTI和AS的冲动传导速度减低更明显 ,并且在CTI的冲动传导速度减慢具有频率依 相似文献
46.
Stem cell factor modulates avidity of alpha 4 beta 1 and alpha 5 beta 1 integrins expressed on hematopoietic cell lines 总被引:4,自引:1,他引:4
Interactions between hematopoietic cells and bone marrow (BM) stroma, composed of extracellular matrix and stromal cells, are crucial for hematopoiesis. Integrins facilitate these interactions by mediating adherence of hematopoiesis. Integrins facilitate these interactions by mediating adherence of hematopoietic cells to both the extracellular matrix and stromal cells. Marrow stromal cells secrete a variety of growth factors, including stem cell factor (SCF). Because treatment with SCF in vivo mobilizes primitive hematopoietic cells from the BM, we investigated the effect of the growth factor SCF of hematopoietic cell adhesion. These studies show that SCF modulates adhesive function in a dose- and time-dependent manner, but does not modulate expression of the integrins alpha 4 beta 1 and alpha 5 beta 1 in the SCF- responsive cell line MO7E. Treatment of MO7E cells with SCF (200 ng/mL) produced a transient increase in adherence to cytokine-activated human umbilical vein endothelial cells (HUVECs) or to vascular cell adhesion molecule 1 (VCAM-1)-transfected Chinese hamster ovary (CHO) cells with peak adhesion at 30 minutes and return to baseline by 60 to 90 minutes. This increase in adhesion was paralleled by increased binding of the beta 1 activation-dependent monoclonal antibody (MoAb) 15/7, as determined by flow cytometry. However, prolonged incubation of MO7E with SCF induced a marked decrease in integrin-mediated adherence, with maximal inhibition by 24 hours. No change in expression of integrins, as determined by flow cytometry, was observed with short- or long-term incubation with SCF. SCF-treated cells were still able to respond to phorbol esters and to the activating beta 1 MoAb 8A2 with increased adherence, but not to the level seen in control cells. This suggests that a subpopulation of expressed alpha 4 beta 1 and alpha 5 beta 1 integrins is disengaged by prolonged incubation with SCF. 相似文献
47.
The transfusion of blood may suppress the immune responses of patients with renal transplants and with malignant disorders. To study the in vitro suppressive effects of banked blood, 4 units of blood were stored in CPDA-1 and ADSOL at 4 degrees C for 14 days. Lymphocytes and plasma or ADSOL supernatants were harvested on Days 0, 4, 7, 10, and 14. Subpopulations of lymphocytes were enumerated by flow cytometry. Recalcified and heat-treated plasma and supernatants from the units of blood were added to mixed lymphocyte cultures (MLC) composed of cells from normal individuals. No significant changes were noted in the proportions of T or B cells from blood stored under these conditions. A 60 +/− 3 percent inhibition in the proliferative response was observed when plasma from CPDA-1 units was added to MLCs (p less than 0.02). Supernatants from ADSOL units demonstrated a 29 +/− 4 percent inhibition (p less than 0.10) of the proliferative response, and this inhibition of response was observed on all 14 days of the study. When appropriate concentrations of dextrose or adenine were added to other MLCs, adenine (at the concentration found in ADSOL) caused a significant inhibition of the proliferative response. This inhibition was not, however, as marked as that observed with recalcified, heat- treated plasma from CPDA-1 units. We conclude that adenine plus some additional factor(s) found in the liquid portion of stored blood inhibits the proliferative response of normal lymphocytes. It is possible that these factors contribute to the immune suppression observed in vivo in some patients who receive blood transfusions. 相似文献
48.
We studied cytotoxic activity of acute myelogenous leukemia (AML) sera for AML blasts before and after immunoadsorption with Staphylococcus aureus, Cowan I (SAC), which contains protein A. We found in vitro that incubation with treated AML sera reduced viability to 42.7% of control (p less than 0.01) for autologous and 21.0% of control (p less than 0.01) for allogeneic blasts. Normal peripheral blood cells were not killed by treated AML sera. Wood 46 strain of Staphylococcus aureus, which does not contain protein A, did not significantly reduce AML blast viability (94.8%, p greater than 0.4), while Sepharose-bound protein A reduced viability to 63.8% (p less than 0.01). Cytotoxicity does not appear to be complement-mediated, byt cytotoxic activity is trypsin-sensitive and is contained in the immunoglobulin fraction. This model for study of the tumoricidal action of protein A adsorption should be useful for predicting utility of plasma adsorption as a therapeutic adjunct in the future. 相似文献
49.
Human umbilical vein endothelial cells display high-affinity c-kit receptors and produce a soluble form of the c-kit receptor 总被引:4,自引:3,他引:4
Stem cell factor (SCF) is a hematopoietic growth factor produced by fibroblasts and endothelial cells that stimulates the growth of primitive hematopoietic cells. SCF triggers cell growth by binding to the c-kit receptor. Because endothelial cells can respond to certain hematopoietic growth factors, we tested human umbilical vein endothelial cells for display of the c-kit receptor and examined the effect of SCF on endothelial cell proliferation, adhesion molecule expression, and production of tissue factor. Quantitative binding experiments with 125I-SCF showed both high-affinity (Kd = 42 pmol/L) and low-affinity (Kd = 1.7 nmol/L) c-kit receptors. There were approximately 1,100 high-affinity c-kit receptors, and 5,400 low- affinity c-kit receptors per endothelial cell. Enzyme immunoassays showed that endothelial cells released soluble c-kit receptor and SCF. The transmembrane form of SCF was detected by indirect immunofluorescence analysis using monoclonal or polyclonal anti-SCF receptor antibodies. The addition of SCF (100 ng/mL) did not alter endothelial cell proliferation over a 7-day period. Similarly, there was no change in the release of tissue factor or expression of inducible endothelial adhesion molecules (intercellular adhesion molecule-1, endothelial-leukocyte adhesion molecule-1, and vascular cell adhesion molecule-1) measured by enzyme-linked immunosorbant assay at 4 and 24 hours after SCF addition. The neutralizing anti-c-kit receptor monoclonal antibody SR-1 blocked binding of 125I-SCF to the c- kit receptor by 98% but did not alter endothelial cell proliferation or adhesion-molecule expression. c-kit receptors were also detected on adult endothelial cells lining small blood vessels in normal human lymph nodes. These data indicate that normal human endothelial cells produce SCF and show high-affinity c-kit receptors that have the capacity to dimerize. The lack of response to exogenous SCF may be because of intracellular activation of the c-kit receptor via autocrine production of SCF. Alternatively, SCF and c-kit may play a role other than stimulation of proliferation, adhesion-molecule display, or tissue factor production by endothelial cells. The production of soluble c-kit receptors by normal human endothelial cells may serve to regulate the bioactivity of SCF within the bone marrow microenvironment. 相似文献
50.
FLT3 receptor expression on the surface of normal and malignant human hematopoietic cells 总被引:3,自引:7,他引:3
FLT3 ligand is a hematopoietic growth factor that plays a key role in growth of primitive hematopoietic cells. FLT3 receptor mRNA is found in early hematopoietic progenitors and in human myeloid leukemia blasts. Much less is known about the surface expression of FLT3 receptor on human hematopoietic cells. Using human 125I-FLT3 ligand, we have identified and characterized surface FLT3 receptors on normal and malignant human hematopoietic cells and cell lines. Our results showed that surface display of FLT3 receptor was greatest in fresh myeloid leukemia blast cells and myeloid leukemia cell lines. Erythroleukemic and megakaryocytic leukemia cell lines (n = 5) bound little to no 125I- FLT3 ligand. Scatchard analysis of 125I-FLT3 ligand binding data shows that three myeloid leukemia cell lines, ML-1, AML-193, and HL-60, as well as normal human marrow mononuclear cells, exhibit high affinity FLT3 receptors. Crosslinking of 125I-FLT3 ligand to FLT3 receptors on the surface of ML-1 myeloid leukemia cells indicates that the FLT3 ligand. The rates of FLT3 ligand internalization and degradation were determined by binding 125I-FLT3 ligand to ML-1 cells and acid stripping to distinguish surface bound from internalized ligand. Internalized 125I-FLT3 ligand was detected within 5 minutes after binding to ML-1 cells. In addition, we evaluated the effect of FLT3 ligand on megakaryocytic colony growth and nuclear endoreduplication, alone or in the presence of thrombopoietin. FLT3 ligand did not promote colony forming unit megakaryocyte (CFU-Meg) colony growth or megakaryocyte nuclear maturation, nor did FLT3 ligand augment the effects of thrombopoietin on these measures of megakaryopoiesis. These data indicate that the FLT3 receptor shares several characteristics with the c-kit receptor including dimerization and rapid internalization. However, the more restricted cellular distribution of the FLT3 receptor may target the effects of FLT3 ligand to primitive hematopoietic cells and to myeloid and lymphoid progenitor cells, in contrast to the pleiotropic effects of the c-kit receptor ligand, stem cell factor. 相似文献