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401.
We previously reported isolation of human T-cell leukemia virus II (HTLV-II) from a second patient (N.R.A.) with atypical hairy cell leukemia. Follow-up analysis of the characteristics of the patient's HTLV-II infection over a 2-year period has revealed that the patient had two coexistant lymphoproliferative disorders. Oligoclonally integrated HTLV-II was detected in DNA extracted from the patient's peripheral blood mononuclear cells on separate occasions greater than 1 year apart, similar to integration of HTLV-I seen in adult T cell leukemia/lymphoma. Although integrated provirus was readily detected, no HTLV-II viral RNA expression was seen in fresh peripheral blood lymphoid cells. Although the patient's peripheral blood consistently contained a majority of atypical lymphoid cells with a T cell antigenic phenotype, he ultimately developed extensive pleural, hepatic and soft tissue infiltration with malignant Tac+, tartrate-resistant, acid phosphatase-positive (TRAP+) B cells of clonal origin. To further characterize the role of HTLV-II, the patient's peripheral blood mononuclear cells were fractionated into four enriched subpopulations at autopsy. Oligoclonally integrated HTLV-II was detected in DNA from a T cell-enriched fraction and a CD8+ T cell-enriched fraction, but not in a CD4+ T cell-enriched fraction, a non-T cell fraction, or in B cells obtained from the malignant pleural effusion. We conclude that the patient harbored two distinct lymphoproliferative disorders, a TRAP+, Tac+ B cell malignancy consistent with hairy cell leukemia that did not contain HTLV-II and a Tac-, CD8+ lymphoproliferative syndrome with oligoclonally integrated HTLV-II.  相似文献   
402.
A deletion mutation causes hemophilia B in Lhasa Apso dogs   总被引:5,自引:3,他引:5  
Mauser  AE; Whitlark  J; Whitney  KM; Lothrop  CD Jr 《Blood》1996,88(9):3451-3455
Hemophilia B is a bleeding disorder caused by a deficiency of clotting factor IX (FIX). A colony of FIX deficient Lhasa Apso dogs has been established and the molecular basis of hemophilia B has been determined. The plasma factor IX levels were < 1% of normal canine levels in affected dogs. A complex deletion mutation at nucleotides 772- 777 was found when hepatocyte cDNA from a hemophilia B dog was sequenced. The sequence was identical to the normal canine sequence except for a deletion including nucleotides 772-776 and a C-->T transition at nucleotide 777. The mutation results in mRNA instability and a premature termination codon in the nucleotide sequence encoding the activation peptide. The mutation was verified by sequencing genomic DNA from an FIX-deficient dog. A genetic test for the detection of heterozygous animals was established using heteroduplex analysis. Although hemophilia B has been described in many dog breeds, this is only the second mutation to be sequenced. The Lhasa Apso dog model should be valuable for evaluating novel strategies for treating hemophilia B such as gene therapy.  相似文献   
403.
Niskanen  E; Gasson  JC; Teates  CD; Golde  DW 《Blood》1988,72(2):806-810
Endotoxin-free purified recombinant human erythroid-potentiating activity (EPA) was administered to normal and bled mice. In anemic ICR mice EPA treatment led to a significant increase in the number of reticulocytes in the peripheral blood and erythroid precursors in the spleen. Stimulation of CFU-E and BFU-E in the spleen was also observed in C3H/HEJ mice, which excluded the possibility of endotoxin effect. Unchanged, 51Cr-tagged red cell survival and lack of radioactivity in the stool or urine suggests that the EPA stimulation of erythropoiesis was not due to hemolysis or bleeding. Thus, EPA has an effect on erythropoiesis in anemic mice in vivo.  相似文献   
404.
405.
Owens  MR; Cimino  CD 《Blood》1985,66(2):402-406
The combined effects of orchiectomy and estrogen administration on synthesis of selected hepatic secretory proteins--antithrombin (AT) III, plasminogen, fibrinogen, factor II (prothrombin), factor VII, fibronectin, and albumin--were studied using the isolated rat liver perfused in vitro for ten hours. Male rat liver donors underwent orchiectomy under ether anesthesia and then received 5.0 mg of diethylstilbestrol (DES) by subcutaneous pellet implantation or a placebo pellet; 14 days later the livers were extracted and perfused in vitro for ten hours. In DES experiments, 1.0 mg of DES was also added directly to the liver perfusate at the outset. Pretreatment with DES resulted in significant increases in cumulative synthesis of factors II (65%) and VII (76%) and significant reduction in cumulative synthesis of both antithrombin III (20%; P = .03) and plasminogen (27%; P less than .01) compared to control perfusions, but synthesis of fibrinogen, fibronectin, and albumin was not significantly affected by addition of the hormone. Plasma samples collected from rat liver donors that had received DES showed similar effects on protein concentrations: significant decreases in concentration of plasminogen and antithrombin III were apparent with no significant changes in concentrations of fibrinogen, fibronectin, or albumin. In additional perfusions, "dose- response" experiments were conducted in which rat liver donors received a subcutaneous DES pellet of 0.5, 5.0, or 50 mg. Synthesis of plasminogen in this group of perfusions was progressively decreased as the concentration of DES administered to the rat liver donor increased. Synthesis of AT III was reduced to the same degree by 5.0 or 50 mg of DES, both being substantially lower than the 0.5-mg experiments. Concentrations of these two proteins in plasma samples from rat liver donors showed changes quite similar to those seen in perfusion experiments; however, plasma fibrinogen concentrations were not different among the three groups of rats.  相似文献   
406.
High-dose chemoradiotherapy followed by marrow transplantation from an HLA-matched sibling donor is curative for patients with acute leukemia. Autologous marrow transplantation has been used with success for some patients without such a sibling. Alternatively, the option of performing a transplant from an HLA-matched unrelated donor has been made possible by the recent development of large registries of HLA- typed volunteers. The purpose of this study was to compare the outcomes for patients with advanced leukemia treated by unrelated or autologous marrow transplantation. Forty-three patients with acute myeloid or lymphoid leukemia were transplanted from a closely HLA-matched unrelated donor. Results were compared with those of a disease-, disease-stage-, and age-matched cohort of 77 patients treated with autologous marrow transplantation at the same institution during the same period. Myeloid reconstitution with peripheral granulocyte counts greater than 10(9)/L was achieved in 93% of unrelated recipients and 70% of autologous recipients at a median of 24 and 36 days after transplantation, respectively (P = .0001). The cumulative proportions of patients discharged alive (79% v 77%) and times from transplant to first hospital discharge (35 v 34 days) were not different between unrelated and autologous recipients (P = .65). For patients transplanted in complete remission, relapse occurred after transplantation in 27% of the unrelated and in 55% of the autologous recipients (P = .08). For patients transplanted in relapse, the corresponding posttransplant relapse rates were 48% and 63%, respectively (P = .72). Forty percent of unrelated recipients and 28% of autologous recipients died in remission. Leukemia-free survivals were 33% for unrelated and 25% for autologous recipients transplanted in remission (P = .45), and 12% for unrelated and 5% for autologous recipients transplanted in relapse (P = .75). Unrelated donor transplants appear no less effective than autologous transplants to achieve long-term survival and may be more effective in eradicating leukemia in patients who have failed conventional chemotherapy. Further studies are warranted to assess the relative effectiveness of unrelated and autologous transplantation performed earlier in the course of the disease.  相似文献   
407.
Intracellular ferriprotoporphyrin IX is a lytic agent   总被引:3,自引:0,他引:3  
Fitch  CD; Chevli  R; Kanjananggulpan  P; Dutta  P; Chevli  K; Chou  AC 《Blood》1983,62(6):1165-1168
Human erythrocytes were treated with menadione to oxidatively denature hemoglobin and release ferriprotoporphyrin IX (ferriheme, FP) intracellularly. The high affinity of FP for chloroquine was used to detect its release. After incubation for 1 hr at 37 degrees C and pH 7.4 with 0.5 mM menadione, erythrocytes bound 14C-chloroquine with an apparent dissociation constant of 10(-6)M. Untreated erythrocytes did not bind chloroquine with high affinity. At a chloroquine concentration in the medium of 2 microM, for example, menadione-treated erythrocytes bound 70 mumole chloroquine/kg and untreated erythrocytes bound 13.4 mumole/kg. The intracellular location of FP released by menadione was verified by finding that Tween 80 did not prevent chloroquine binding. By contrast, Tween 80 inhibited the binding of chloroquine to erythrocytes treated with extracellular FP. The hemolytic response to menadione was characteristic of the hemolytic response to FP. Thus, 5 microM chloroquine caused hemolysis to increase to 60% from baseline values of 5% in experiments using erythrocytes treated either with 0.5 mM menadione or with 5 microM FP; and, in both cases, the potentiating effect of chloroquine was inhibited by 1 microM mefloquine or 10 microM quinine. Higher concentrations of menadione caused hemolysis in the absence of chloroquine. We conclude that FP released by menadione exists intracellularly in a form that is accessible to bind chloroquine and to express its lytic activity.  相似文献   
408.
409.
Our language both reflects and influences our attitudes and behavior. This Roundtable Discussion explores the language used in obstetrics and in the interactions between caregivers and women or their families: What do practitioners say to mothers and families during labor? At birth? In consultations? To describe what is happening? To encourage a woman's efforts? To lighten the atmosphere? When advising about possible interventions? Medical terminology in perinatal care can often be deceptive or confusing, not only for mothers but for caregivers. The authors of this Roundtable, representing health professionals from different specialties and interests in the field, have examined some examples of such language use, misuse, and abuse in perinatal care. (BIRTH 39:2 June 2012)  相似文献   
410.
头颈部鳞癌(HNSCC)患者生存率的统计通常是从疾病被诊断时开始.但对疾病确诊后生存一段时间的患者很少应用条件生存率(conditional survival,CS)进行分析,CS分析能够提供判断患者预后的重要信息。该文旨在应用大规模的癌症数据库寻求CS参数。对1973~1998年间美国国立癌症研究院(the National Cancer Institute。NCI)的监测、流行病学和最终结果(the surveillance,epidemiology and end-results,SEER)计划(Surveillance.Epidemiology,and End Results,  相似文献   
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