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排序方式: 共有1844条查询结果,搜索用时 15 毫秒
31.
Bolontrade MF; Stern MC; Binder RL; Zenklusen JC; Gimenez-Conti IB; Conti CJ 《Carcinogenesis》1998,19(12):2107-2113
In this study we have analyzed the vascular response induced in the two-
stage carcinogenesis model in SENCAR mice. The role of angiogenesis has not
been explored in this model, which is the paradigm of multistage
carcinogenesis and a model for neoplastic lesions derived from exophytic
premalignant lesions (e.g. colon carcinoma, bladder papilloma). We
investigated if angiogenesis is involved in the formation of papillomas and
in the progression from papilloma to carcinoma. To this end we analyzed the
vasculature of normal and hyperplastic skin, focal epidermal hyperplasias
that are precursors of papillomas, papillomas at different stages and
squamous cell carcinomas. We also analyzed the vascularization of
papillomas induced in two strains of mice that differ in their
susceptibility to malignant progression. We show here that angiogenesis is
turned on in the earliest stages of papilloma formation. In late stages,
regardless of state of progression, the predominant response is an increase
in the size of blood vessels. Thus, in the SENCAR mouse model,
representative of exophytic tumors, the angiogenesis switch is a very early
event, probably mechanistically related to the development of the primarily
exophytic lesions. Therefore, the density of blood vessels cannot be used
as a predictor of malignant progression in this model.
相似文献
32.
为了寻找毒性低、增敏作用强的乏氧细胞放射增敏剂,设计并合成了一系列5-溴-,5-甲基-,和5-未取代的3-硝基-1,2,4-三唑-1-乙酰胺类化合物,用HeLaS3细胞进行了体外试验。结果表明5-溴取代衍生物的增敏作用强于相应的5-甲基-或5-未取代的硝基三唑衍生物,但是它们的毒性亦增大。修饰1位乙酰胺侧链也可以改变化合物的增敏作用和亲脂性。在所测定的化合物中TA-101[2-(3-硝基-1-三唑基)乙酰胺]由于有高的增敏作用和低亲脂性,可能是一个有希望的放射增敏剂。 相似文献
33.
S. Kirk S. Beatty P. Callery J. Gellatly L. Milnes S. Pryjmachuk 《Child: care, health and development》2013,39(3):305-324
Children's health policy has highlighted the need to develop self‐care programmes. However, there is a lack of evidence on which to base the development of such programmes. This paper reviews the published research on the effectiveness of self‐care support interventions for children and young people with asthma, cystic fibrosis and diabetes. A systematic search was conducted of a range of electronic databases, supplemented by searching the reference lists of retrieved papers and published reviews. Retrieved studies were assessed against quality and eligibility criteria by two independent reviewers. The results were narratively synthesized to examine the effectiveness of self‐care support interventions on health status, psycho‐social well‐being, condition‐related knowledge, health service use and participant satisfaction. The search strategy identified 4261 papers which were screened against the review inclusion criteria. A total of 194 papers were assessed as being potentially eligible for inclusion with 15 papers being judged as adequate to include in the review. There is strong evidence of the effectiveness of interventions that target children/young people; use e‐health or group‐based methods; that are delivered in community settings. There is no evidence that interventions that focus on parents alone or are delivered only in hospital settings are effective. While there is some evidence to inform the development of self‐care support programmes, there is a need for well‐designed trials of interventions that are feasible to transfer into real‐life settings and which involve parents and children in their development. 相似文献
34.
Splenic lymphangiomatosis in children 总被引:14,自引:0,他引:14
35.
36.
F reticulocyte response in sickle cell anemia treated with recombinant human erythropoietin: a double-blind study 总被引:1,自引:0,他引:1
Nagel RL; Vichinsky E; Shah M; Johnson R; Spadacino E; Fabry ME; Mangahas L; Abel R; Stamatoyannopoulos G 《Blood》1993,81(1):9-14
Studies on baboons and preliminary observations in three patients with sickle cell anemia (SS) suggested that high doses of pulse administered recombinant human erythropoietin (rHuEPO) stimulate F-reticulocyte production. We now report on the administration of rHuEPO in a double- blind format to ascertain frequency of response and potential precipitation of side effects. Ten patients were enrolled, but one was discontinued due to the indication of a blood transfusion. Of the other nine, five received rHuEPO in escalating doses (from 400 to 1,500 U per kg twice daily [BID] per week), alternating with a placebo, in blinded fashion. The second group, consisting of four patients, followed an identical protocol (except starting dose was 1,000 U/Kg, BID per week) and were iron supplemented during treatment. The criterion of response was a transient doubling (as a minimum) of the steady-state F- reticulocyte level. We found that none of the five patients in the first group responded to rHuEPO, and two of them became iron deficient, as judged by a significant decrease in ferritin. Of the second group, four patients responded with F-reticulocyte increases. In three patients, open label administration of rHuEPO confirmed the effect. We observed seven painful episodes during this study, two during the EPO administration and five during the placebo arm. Three patients were phlebotomized because the hemoglobin level increased 1.5 g/dL more than steady-state levels. Of the six patients followed-up by percent dense cell determinations, one exhibited increased levels during periods of the treatment, whereas the other five showed no change. No anti-rHuEPO antibodies were detected. We conclude that rHuEPO can stimulate F- reticulocyte response in some patients with sickle cell anemia, without apparent negative clinical side effects. The state of iron stores may be critical. Whether higher doses of rHuEPO and/or a different regimen might induce sustained F cells and fetal hemoglobin increases remains to be determined. 相似文献
37.
38.
K Doney L D Fisher F R Appelbaum C D Buckner R Storb J Singer A Fefer C Anasetti P Beatty W Bensinger 《Bone marrow transplantation》1991,7(6):453-459
Between February 1972 and December 1987, 192 adults (greater than or equal to 18 years old) with acute lymphoblastic leukemia were transplanted using genotypically HLA-identical marrow donors. Median patient age was 23 years. Eighty-nine patients were in marrow remission and 103 were in relapse. Conditioning regimens included chemotherapy alone (three patients) or in combination with 9.2-17.5 Gy total body irradiation (189 patients). Graft-versus-host disease (GVHD) prophylaxis consisted of methotrexate and/or cyclosporine. Seventy-nine patients developed grades II-IV acute GVHD and 28 of 122 patients who survived at least 100 days developed chronic GVHD. Relapse-free survival at 5 years was 21% for patients transplanted in first remission, 15% for those in greater than or equal to 2nd remission, and 12% for those transplanted in relapse. Patient and donor characteristics were evaluated in multivariate analyses for their effect on development of acute GVHD, survival, relapse, and relapse-free survival. An increased risk of developing acute GVHD was associated with increasing donor age. Variables significantly associated with both increased survival and relapse-free survival included transplantation in first remission, younger patient age, and not developing interstitial pneumonia. A decreased probability of relapse was associated with transplantation in first remission, male patient sex, and grades II-IV acute GVHD. 相似文献
39.
Allogeneic marrow transplantation in patients with chronic myeloid leukemia in the chronic phase: a randomized trial of two irradiation regimens 总被引:1,自引:5,他引:1
R A Clift C D Buckner F R Appelbaum E Bryant S I Bearman F B Petersen L D Fisher C Anasetti P Beatty W I Bensinger 《Blood》1991,77(8):1660-1665
A randomized trial was performed to compare two regimens of total body irradiation in patients with chronic myeloid leukemia treated by allogeneic marrow transplantation while in the chronic phase. All patients received cyclophosphamide 120 mg/kg followed by total body irradiation and marrow from HLA-identical siblings. Cyclosporine and methotrexate were used for prophylaxis against acute graft-versus-host disease. Fifty-seven patients were randomized to receive 2.0 Gy fractions of irradiation daily for 6 days and 59 were randomized to receive 2.25 Gy fractions daily for 7 days. The probabilities of relapse at 4 years were 0.25 for the 12.0 Gy group and 0.00 for the 15.75 Gy group (P = .008). The actuarial probabilities of survival and relapse-free survival at 4 years were 0.60 and 0.58 among the patients who received 12.0 Gy compared with 0.66 and 0.66 for those who received 15.75 Gy. The 4-year probabilities of transplant-related mortality were 0.24 and 0.34 respectively (P = .13) while the probability of moderate to severe acute graft-versus-host disease was 0.33 for the 12.0 Gy group and 0.44 for the 15.75 Gy group (P = .15). The lower relapse probability in the patients receiving the higher dose of total body irradiation did not result in improved survival because mortality from causes other than relapse was increased. 相似文献
40.