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排序方式: 共有640条查询结果,搜索用时 15 毫秒
81.
CJ Keith M Griffiths B Petersen RJ Anderson KA Miles 《Journal of Medical Imaging and Radiation Oncology》2002,46(3):221-230
The development of thrombolytic and neuroprotective agents for the treatment of acute stroke has created an imperative for improved imaging techniques in the assessment of acute stroke. Five cases are presented to illustrate the value of perfusion CT in the evaluation of suspected acute stroke. To obtain the perfusion data, a rapid series of images was acquired without table movement following a bolus of contrast medium. Cerebral blood flow, cerebral blood volume and mean transit time were determined by mathematically modelling the temporal changes in contrast enhancement in the brain and vascular system. Pixel‐by‐pixel analysis allowed generation of perfusion maps. In two cases, CT‐perfusion imaging usefully excluded acute stroke, including one patient in whom a low‐density area on conventional CT was subsequently proven to be tumour. Cerebral ischaemia was confirmed in three cases, one with an old and a new infarction, one with a large conventional CT abnormality but only a small perfusion defect, and one demonstrating infarct and penumbra. Perfusion CT offers the ability to positively identify patients with non‐haemorrhagic stroke in the presence of a normal conventional CT, to select those cases where thrombolysis is appropriate, and to provide an indication for prognosis. 相似文献
82.
<正>电子结肠镜检查是诊断和筛查肠道疾病常用、有效的检查方法之一,而进行结肠镜检查的基本条件是清洁良好的肠道准备。虽然近年来肠道清洁剂的商品化和肠道准备方法的标准化不断完善,但仍有约30%的患者肠道准备不充分[1-3]。不充分的肠道准备会导致检查时间延长、操作难度增加、病变检出率降低、漏诊及检查费用增加等。肠道准备的质量多与患者的依从性有关,加强对患者肠道准备相关知识的教育,增强患者对肠道准备方法的认识和理解,可以提高检查前的肠道准备质量[4 相似文献
83.
Progressive platelet activation with storage: evidence for shortened survival of activated platelets after transfusion 总被引:14,自引:0,他引:14
HM Rinder ; M Murphy ; JG Mitchell ; J Stocks ; KA Ault ; RS Hillman 《Transfusion》1991,31(5):409-414
Platelets are known to become activated during storage, but it is unclear whether such activation affects recovery or survival after platelet concentrate (PC) transfusion. With the use of flow cytometry to determine the percentage of platelets expressing the alpha-granule membrane protein 140 (GMP-140), a known adhesive ligand appearing on the platelet surface after activation, several studies were conducted. These investigations evaluated 1) the occurrence of significant platelet activation over time in PCs (n = 46) stored under standard blood bank conditions; 2) the correlation between platelet activation and platelet recovery in normal subjects after PC storage (n = 12), as assessed by the recovery of Indium-labeled platelets; and 3) the recovery of activated and unactivated platelets in thrombocytopenic cancer patients transfused with standard PCs (n = 11). It was determined 1) that an increasing duration of storage of PC was associated with increasing platelet activation as measured by the percentage of platelets expressing GMP-140, progressing from a mean of 4 +/- 2 percent (SD) on the day of collection to a mean of 25 +/- 8 percent by 5 days of storage: 2) that, in normal subjects, posttransfusion recovery of autologous platelets stored for 2 to 4 days and then labeled with In111 was inversely correlated with the percentage of activated platelets in the transfused PC (r = -0.55, p = 0.05); and 3) that, when thrombocytopenic patients were transfused with standard PCs, the recovery of the activated platelets in the transfused PCs averaged only 38 +/- 15 percent of the number predicted by the absolute platelet increment.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
84.
85.
We have found that the addition of 10 mM inorganic phosphate to DHA in CPD-adenine maintains ATP levels at normal or higher than normal values for six weeks of storage. 2,3-DPG values are slightly lowered by the extra phosphate, but are still maintained at approximately half normal for four weeks by the DHA. The addition of a higher phosphate concentration, 20 mM, to DHA produced lower levels of ATP and 2,3-DPG than those observed with 10 mM phosphate, although both levels were better than in the CPD-adenine control. pH values in this experiment were lowest in the three preservatives containing DHA, probably indicating increased lactate production due to metabolism of this triose sugar, in addition to dextrose present in CPD. 相似文献
86.
Pullen DJ; Sullivan MP; Falletta JM; Boyett JM; Humphrey GB; Starling KA; Land VJ; Dyment PG; Vats T; Duncan MH 《Blood》1982,60(5):1159-1168
In an attempt to improve the poor outlook for children with T-cell leukemia (T-ALL), the Southwest Oncology Group, Pediatric Division, used a modified LSA2-L2 multidrug regimen to treat 53 patients with E- rosette-positive T-ALL. This regimen was chosen because of its demonstrated efficacy in T-cell (mediastinal) non-Hodgkin's lymphoma. Complete remission (CR) rate was 88%. Range of follow-up for those patients remaining in CR is 24-49 mo (median 39 mo). Life table analysis estimates that 40% (SE 8.3%) of all patients who started induction therapy will remain failure-free at 3 yr. For patients achieving CR, 46% (SE 9%) are projected to remain in both marrow and extramedullary CR at 3 yr. Median failure-free duration was 13 mo, but only 1 patient has relapsed beyond 16 mo. Twenty-nine percent of initial relapses were isolated CNS relapses. The following presenting factors did not relate significantly to outcome: hemoglobin, platelet count, uric acid, race, and mediastinal mass. Age greater than 10 yr was a poor prognosis indicator only in the less than 50,000/microliter WBC group. Sex was not a significant factor after adjusting for WBC. WBC was the most important prognostic factor: 19% (SE 8%) of patients with WBC greater than 50,000/microliter are projected to remain failure- free at 3 yr as compared to 67% (SE 11%) of patients with WBC less than 50,000/microliter. Although the overall results are better than those previously reported for pediatric patients with T-ALL, the long-term failure-free rate remains low for patients presenting with greater than 50,000/microliter WBC. 相似文献
87.
卡世全 《中国肝脏病杂志(电子版)》2012,4(1):20-22
目的观察六味五灵片联合替比夫定治疗活动性慢性乙型肝炎(CHB)肝硬化的临床疗效。方法将72例HBV DNA、HBeAg阳性的CHB肝硬化患者随机分为治疗组和对照组,两组均为36例。治疗组给予六味五灵片联合替比夫定治疗,对照组单用替比夫定治疗,疗程均为24周。治疗前后分别检测患者肝功能、慢性HBV标志物、HBV DNA低于检测下限的比率。结果治疗组血清ALT、AST下降明显,与对照组比较,差异有统计学意义(P〈0.05),治疗组HBeAg低于检测下限的比率及HBeAg/抗-HBe血清转换率均高于对照组,治疗组总有效率高于对照组,差异有统计学意义(P〈0.05)。结论六味五灵片联合替比夫定治疗活动性CHB肝硬化疗效显著,不良反应发生率小,疗效优于单一用药组,是治疗活动性CHB肝硬化的有效方法。 相似文献
88.
Chromosome 7 long arm deletion in myeloid disorders: a narrow breakpoint region in 7q22 defined by molecular mapping 总被引:5,自引:0,他引:5
Kere J; Ruutu T; Davies KA; Roninson IB; Watkins PC; Winqvist R; de la Chapelle A 《Blood》1989,73(1):230-234
The involvement of the erythropoietin (EPO), plasminogen activator inhibitor type I (PAI1), and multi-drug resistance (MDR2) genes located in chromosomal region 7q21-22 was studied in patients with myeloid disorders and with or without a chromosome 7 abnormality. Separated blood mononuclear cells and granulocytes from 21 patients were used in restriction fragment length polymorphism (RFLP) studies with gene- specific DNA probes. A marked weakness of one of the allelic bands was observed in granulocyte-derived DNA from heterozygous patients with monosomy 7. In four patients with a partial deletion of chromosome 7 long arm (7q-), marked weakness of an allelic band was observed in granulocyte-derived DNA with PAI1 probe (four heterozygous patients) and MDR2 probe (one heterozygous patient), implying deletion of these genes. In contrast, the EPO gene was not deleted in these patients, as demonstrated by the presence of two allelic bands of equal strength in granulocyte-derived DNA (two patients) or by gene dosage estimation (two patients). Two allelic bands of equal strength were also observed in three heterozygous patients with an arbitrary probe (pKV13) located in 7cen-q21.3. Unexpected hemizygosity or hybridization bands were not observed in any patient. We conclude that PAI1 and MDR2 are located distally of EPO in 7q22, and that none of these genes is commonly rearranged in myeloid disorders. The chromosome 7 long arm deletion breakpoint is located in a relatively narrow segment between the PAI1 and EPO genes in different patients. The deletion may involve a specific site in DNA, since the genetic distance between the PAI1 and EPO genes is only 3 cM. 相似文献
89.
al-Shahi R; Mason JC; Rao R; Hurd C; Thompson EM; Haskard DO; Davies KA 《Rheumatology (Oxford, England)》1997,36(7):794-798
Thrombocytopenia in patients with acute systemic lupus erythematosus (SLE)
frequently presents the clinician with considerable diagnostic and
therapeutic difficulties. In this Grand Round, we present a 48-yr- old
woman with a 7 yr history of lupus, who presented with acute proliferative
glomerulonephritis and nephrotic syndrome, pneumonia, profound
hypocomplementaemia and a severe microangiopathic haemolytic anaemia with
associated thrombocytopenia. Her thrombocytopenia proved initially
refractory to conventional immunosuppressive therapy, and corticosteroids,
and resolved only with plasma exchange and repeated fresh frozen plasma
infusions. Serological testing revealed high-titre antinuclear antibodies
(ANA) and markedly raised antibodies to double- stranded (ds) DNA, but no
significant elevation in anticardiolipin antibodies. Platelet-associated
IgG and IgM and antibodies to the CD36 glycoprotein antigen, expressed on
platelets and endothelium, were detected in the serum. We address some of
the difficult diagnostic and management issues raised by this complex
patient and the possible immunopathological links between antibodies to
CD36, immune-mediated red cell destruction, thrombocytopenia and thrombotic
microangiopathic haemolytic anaemia.
相似文献
90.
Faltynek CR; Princler GL; Rossio JL; Ruscetti FW; Maluish AE; Abrams PG; Foon KA 《Blood》1986,67(4):1077-1082
Patients with hairy cell leukemia (HCL) and chronic lymphocytic leukemia (CLL) were treated with recombinant interferon alpha A (rIFN- alpha A). The binding of iodinated recombinant interferon-alpha to baseline samples of peripheral blood mononuclear cells (PBMCs) from the leukemia patients was compared with clinical responsiveness to rIFN- alpha A. HCL patients (8/10) responded to rIFN-alpha A therapy, whereas none (0/10) of the CLL patients studied responded. The PBMCs from the eight responsive HCL patients bound approximately twice as much iodinated interferon as the PBMCs from nonresponsive CLL patients. This difference was due to more high-affinity receptors per cell with no difference in the affinity of the interferon-receptor interaction. However, because PBMCs from HCL patients were larger than PBMCs from CLL patients, the cell surface receptor density was similar. The leukemic cells from one of the two nonresponsive HCL patients bound iodinated interferon similarly to the cells from the responsive HCL patients, whereas the leukemic cells from the other nonresponsive HCL patient bound considerably less. The rapidity of response of the HCL patients did not correlate with the level of binding of iodinated interferon. Our results suggest that the absolute number of interferon receptors per cell may be only one of several important parameters in the response to rIFN-alpha A therapy, and that the responsiveness of a particular lymphoproliferative disease or a particular patient to rIFN- alpha A therapy cannot be predicted or explained solely by the degree of interaction between IFN and its cell surface receptor. 相似文献