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排序方式: 共有966条查询结果,搜索用时 0 毫秒
941.
Marrow transplantation from unrelated donors for treatment of hematologic malignancies: effect of mismatching for one HLA locus 总被引:3,自引:5,他引:3
Beatty PG; Anasetti C; Hansen JA; Longton GM; Sanders JE; Martin PJ; Mickelson EM; Choo SY; Petersdorf EW; Pepe MS 《Blood》1993,81(1):249-253
One hundred twelve patients less than 36 years old received marrow grafts from unrelated donors as treatment for hematologic malignancy. Seventy donor/recipient pairs were phenotypically identical for HLA-A, - B, and -D, while 42 had a "minor" disparity at one HLA locus. There was an increase in the risk of acute graft-versus-host disease (GVHD) in patients receiving HLA-partially matched grafts compared with those receiving HLA-matched grafts (51% v 36% probability of grades III-IV acute GVHD). However, in this cohort of patients, there was no significant difference in survival (at 1.5 years, 46% v 51% for good- risk patients, 44% v 30% for poor-risk patients). This finding suggests that some degree of HLA disparity can be tolerated in young patients transplanted from unrelated donors for malignant disease, thus making transplantation an option available to larger numbers of patients. 相似文献
942.
943.
Kinetic studies have been carried out to investigate the functional heterogeneity previously observed in populations of human marrow or peripheral blood cells separated by velocity sedimentation. The results obtained confirm the earlier results, in that slowly-sedimenting cells were found to stimulate both colony formation by granulopoietic progenitors and an increase in numbers of granulopoietic progenitors in suspension culture, while rapidly-sedimenting cells stimulated only colony formation and not increased progenitors in suspension cultures. Investigations of the properties of media conditioned by these two subpopulations of cells revealed no clear differences between them; both stimulated suspension cultures as well as colony formation, and both lost the former activity, but not the latter, after dialysis. The results contribute to the evidence that more than one process is regulated in cultures of granulopoietic progenitor cells. 相似文献
944.
Phosphatidylinositol 3-kinase associates, via its Src homology 2 domains, with the activated erythropoietin receptor 总被引:8,自引:2,他引:8
The erythropoietin receptor (EpR) belongs to a family of hematopoietin receptors whose members lack tyrosine kinase activity. Nonetheless, within minutes of binding Ep, a number of cellular proteins become transiently phosphorylated on tyrosine residues. One of these proteins, as we and others have shown previously, is the EpR itself. To identify the remaining protein substrates, we have examined the antiphosphotyrosine immunoprecipitates of lysates from Ba/F3 cells expressing high levels of cell surface EpRs. We now present data showing that, in response to Ep, the 85-Kd regulatory subunit of phosphatidylinositol 3-kinase (PI 3-kinase) becomes immunoprecipitable with antiphosphotyrosine antibodies. This appears to be due, in large part, to the specific association of PI 3-kinase with the tyrosine- phosphorylated EpR, either directly or through a 93- or 70-Kd tyrosine- phosphorylated intermediate. The activity of this EpR associated PI 3- kinase, assessed in anti-EpR immunoprecipitates, is maximal within 2 minutes of incubation with Ep and returns almost to baseline levels by 10 minutes. In vitro studies suggest that the interaction between PI 3- kinase and the activated EpR is mediated by the N- and C-terminal SH2 domains of p85 and tyrosine-phosphorylated motifs on the EpR. 相似文献
945.
Delineation of an immunodominant and human T-cell lymphotropic virus (HTLV)-specific epitope within the HTLV-I transmembrane glycoprotein 总被引:3,自引:0,他引:3
Hadlock KG; Goh CJ; Bradshaw PA; Perkins S; Lo J; Kaplan JE; Khabbaz R; Foung SK 《Blood》1995,86(4):1392-1399
Antibody reactivity to the transmembrane region of human T-cell lymphotropic virus type I (HTLV-I) envelope, gp21, is observed in virtually all individuals infected with HTLV-I or HTLV-II. Recombinant proteins encoding selected portions of gp21 are described and used to define two immunogenic regions. The first epitope (designated GD21-I) contains amino acids 361 to 404 of the HTLV-I envelope and reacted with all of 54 sera from HTLV-I- and HTLV-II-infected individuals. The second epitope (designated BA21) expresses amino acids 397 to 430 of the HTLV-I envelope and was recognized by 33 of 54 HTLV antisera. To determine the specificity of GD21-I and BA21, sera from 17 HTLV- negative individuals with nonspecific reactivity to p21E were tested. None of these sera reacted with GD21-I, but 16 of 17 sera reacted with BA21. With virtually complete reactivity to sera from HTLV-infected individuals and no reactivity to sera from p21E-reactive uninfected individuals, GD21-I will be useful in immunoassays for the detection of HTLV infection. 相似文献
946.
Impaired megakaryocytopoiesis may be a contributing factor to thrombocytopenia associated with human immunodeficiency virus (HIV) infection. Because HIV isolates differ in their host range and pathogenicity, we investigated whether HIV strains with demonstrable cell tropism and increased cytopathicity for megakaryocytes could be derived from the blood of thrombocytopenic HIV-infected individuals. We derived a strain, HIV-WW, from the peripheral blood of an individual with severe thrombocytopenia and found the virus to be highly and specifically cytotoxic to CMK and DAMI megakaryocytic cells. CMK and DAMI cells were not permissive for the virus and HIV-WW induced cytopathicity for these megakaryocytic cells did not depend on viral replication. The CD4 N-terminus-binding domain of the HIV gp120 envelope protein did not appear to be involved in determining the cytopathic phenomenon. HIV may impair megakaryocytopoiesis through interactions at the cell surface in some cases rather than through viral entry and intracellular replication. 相似文献
947.
Successful transplantation of HLA-matched and HLA-mismatched umbilical cord blood from unrelated donors: analysis of engraftment and acute graft-versus-host disease 总被引:21,自引:15,他引:21
Wagner JE; Rosenthal J; Sweetman R; Shu XO; Davies SM; Ramsay NK; McGlave PB; Sender L; Cairo MS 《Blood》1996,88(3):795-802
To reduce the morbidity and mortality associated with unrelated donor bone marrow (BM) transplantation and potentially extend the pool of suitable donors, cryopreserved unrelated donor umbilical cord blood was considered as an alternate source of hematopoietic stem cells for transplantation. Patients with leukemia, BM failure syndrome, or inborn error of metabolism were eligible for a phase I clinical trial designed to estimate the risk of graft failure and severe acute graft-versus- host disease after transplantation of umbilical cord blood from unrelated donors. As of December 21, 1995, unrelated donor umbilical cord blood was used to reconstitute hematopoiesis in eighteen patients aged 0.1 to 21.3 years weighing 3.3 to 78.8 kg with acquired or congenital lympho-hematopoietic disorders or metabolic disease. Patients received either HLA-matched (n = 7) or HLA-1 to 3 antigen disparate (n = 11) grafts collected and evaluated by the New York Blood Center (New York, NY). The probability of engraftment after unrelated donor umbilical cord blood transplantation was 100% with no patient having late graft failure to date. The probability of grade III-IV acute graft-versus-host disease at 100 days was 11%. With a median follow-up of 6 months (range, 1.6 to 17 months); the probability of survival at 6 months is 65% in this high risk patient population. We conclude that cryopreserved umbilical cord blood from HLA-matched and mismatched unrelated donors is a sufficient source of transplantable hematopoietic stem cells with high probability of donor derived engraftment and low risk of refractory severe acute graft-versus-host disease. Limitations with regard to recipient size and degree of donor HLA disparity remain to be determined. 相似文献
948.
Nicole JE Horevoorts Pauline AJ Vissers Floortje Mols Melissa SY Thong Lonneke V van de Poll-Franse 《Journal of medical Internet research》2015,17(5)
Background
Improving questionnaire response rates is an everlasting issue for research. Today, the Internet can easily be used to collect data quickly. However, collecting data on the Internet can lead to biased samples because not everyone is able to access or use the Internet. The older population, for example, is much less likely to use the Internet. The Patient-Reported Outcomes Following Initial Treatment and Long-Term Evaluation of Survivorship (PROFILES) registry offers a platform to collect Web-based and paper questionnaires and to try different measures to improve response rates.Objective
In this study, our aim was to study the influence of two methods of invitation on the response rate. Our second aim was to examine the preference of questionnaire mode of administration (paper or Web-based) for the older patient in particular.Methods
To test these two invitational methods, 3406 colorectal cancer patients between ages 18 and 85 years received an invitation containing an access code for the Web-based questionnaire. They could also request a paper questionnaire with an included reply card (paper-optional group). In contrast, 179 randomly selected colorectal cancer patients received a paper questionnaire with the invitation (paper-included group). They could also choose to fill out the Web-based questionnaire with the included access code.Results
Response rates did not differ between the paper-optional and the paper-included groups (73.14%, 2491/3406 and 74.9%, 134/179, P=.57). In the paper-optional group, online response was significantly higher when compared to the paper-included group (41.23%, 1027/2491 vs 12.7%, 17/134, P<.001). The majority of online respondents responded after the first invitation (95.33%, 979/1027), which was significantly higher than the paper respondents (52.19%, 764/1464, P<.001). Respondents aged 70 years and older chose to fill out a paper questionnaire more often (71.0%, 677/954). In the oldest age group (≥80 years), 18.2% (61/336) of the respondents filled out a Web-based questionnaire.Conclusions
The lack of difference in response rates between invitation modes implies that researchers can leave out a paper questionnaire at invitation without lowering response rates. It may be preferable not to include a paper questionnaire because more respondents then will fill out a Web-based questionnaire, which will lead to faster available data. However, due to respondent preference, it is not likely that paper questionnaires can be left out completely in the near future. 相似文献949.
SA Khan MRCP JE Pace MRCP ML Cox MRCP DW Gau FRCGP SAL Cox MRCGP HM Hodkinson FRCP 《International journal of clinical practice》1994,48(5):240-242
SUMMARY The incidence of climacteric symptoms was determined in 247 healthy premenopausal women in a community setting. These volunteers had been recruited to a longitudinal study of bone density. Of these subjects, 46 ceased to menstruate during the study, and in this subgroup symptoms were compared before and after cessation of menstruation. Only hot flushes increased after cessation of menstruation in the longitudinal study and showed age correlation in the cross-sectional study. Hot flushes thus emerged as a true menopausal symptom. Although evidence for this is weaker, cold sweats and suffocation seem likely to be genuinely menopausal. Breast discomfort and the four mood symptoms of irritability, excitability, depression and poor concentration improved after cessation of menstruation, and this study gives no support for their being part of the menopausal syndrome; it suggests that these symptoms are more likely to be related to menstruation than to the menopause. 相似文献
950.
BACKGROUND: The clinical utility of polymorphonuclear neutrophil (PMN) transfusion therapy has been compromised, in part, by the inability to obtain sufficient quantities of functional neutrophils from donors. To define the optimal conditions for mobilization of PMNs in granulocyte donors, the effects of granulocyte-colony-stimulating factor (G-CSF) and dexamethasone, separately and in combination, on PMN counts in normal volunteers were compared. STUDY DESIGN AND METHODS: Five normal subjects were randomly assigned to each of the following single-dose regimens in 5 consecutive weeks: 1) G-CSF, 300 micrograms given subcutaneously; 2) G-CSF, 600 micrograms subcutaneously: 3) dexamethasone, 8 mg given orally; 4) G-CSF, 300 micrograms subcutaneously, plus dexamethasone, 8 mg orally; and 5) G-CSF, 600 micrograms subcutaneously, plus dexamethasone 8 mg orally. Venous blood was collected at 0, 6, 12, and 24 hours after drug administration for the determination of absolute neutrophil counts (ANCs). RESULTS: Maximal ANC was achieved at 12 hours after each regimen, except dexamethasone alone (maximum, 24 hours). Dexamethasone significantly increased the maximal ANC induced by either dose of G-CSF alone (p < 0.05). The greatest mobilization of PMNs occurred after the administration of G-CSF (600 micrograms) and dexamethasone (8 mg); the ANC increased from a mean baseline value of 3,594 per microL to 43,017 per microL at 12 hours. All of the drug regimens were well tolerated. CONCLUSION: Dexamethasone significantly increases the level of neutrophilia induced in normal subjects by G-CSF. The combination of dexamethasone and G-CSF (at the dosages used in this study) is a convenient, well-tolerated regimen for the mobilization of PMNs in the peripheral blood of granulocyte donors. Moreover, the optimal quantitative yield of PMNs is likely to be achieved by leukapheresis 12 hours after drug administration. 相似文献