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101.
102.
Candidate HIV-1 gp140DeltaV2, Gag and Tat vaccines protect against experimental HIV-1/MuLV challenge
Bråve A Hinkula J Cafaro A Eriksson LE Srivastava IK Magnani M Ensoli B Barnett SW Wahren B Rollman E 《Vaccine》2007,25(39-40):6882-6890
Pre-clinical HIV-1 vaccine protocols, using multiple vaccine modalities and a potent adjuvant were assessed for vaccine efficacy in an experimental HIV-1 challenge model. C57Bl/6 mice were immunized with DNA plasmids encoding HIV-1 gp140, Gag and Tat alone or in combination with the corresponding recombinant proteins formulated in the adjuvant MF59. HIV-1 DNA alone or a DNA prime protein boost schedule resulted in complete protection against challenge with HIV-1/MuLV-infected murine cells. Although HIV-1 protein immunization in combination with MF59 resulted in partial protection, the DNA priming seemed to be crucial for obtaining full protection against the challenge. It is likely that the partial protection seen after immunization with protein alone is, to a certain extent, due to effects of the adjuvant since some animals that received the adjuvant MF59 alone were protected from the challenge. For the most part, antigen-specific cell-mediated immune responses as detected in the spleen (in contrast to responses detected in peripheral blood) of immunized animals appeared to be associated with protection in this study. 相似文献
103.
Comparison of Electronic Physician Prompts versus Waitroom Case-Finding on Clinical Trial Enrollment
Background Recruiting patients into clinical research protocols is challenging. Electronic medical record (EMR) systems capable of prompting
clinicians may facilitate enrollment.
Objective To compare an EMR-based clinician prompt versus a wait-room-based case-finding strategy at enrolling patients into a clinical
trial.
Design Cross-sectional comparison of recruitment data from two trials to treat anxiety disorders in primary care. Both studies utilized
similar enrollment criteria, intervention strategies, and the same four practice sites and EMR system.
Participants Patients referred by their (primary care physicians) PCPs in response to an EMR prompt (recruited 1/2005–10/2006), and patients
enrolled by research assistants stationed in practice waiting rooms (7/2000–4/2002).
Measurements Referral counts, patients’ baseline sociodemographic and clinical characteristics.
Results Over a 22-month period, EMR-prompted PCPs referred 794 patients and 176 (22%) met study inclusion criteria and enrolled, compared
to 8,095 patients approached by wait room-based recruiters of whom 193 (2.4%) enrolled. Subjects enrolled by EMR-prompted
PCPs were more likely to be non-white (23% vs 5%; P < 0.001), male (28% vs 18%; P = 0.03), and have higher anxiety levels than those recruited by wait-room recruiters (P < 0.0001).
Conclusions EMR systems prompting clinicians to refer patients with specific characteristics are an efficient recruitment tool with critical
implications for increasing minority participation in clinical research. 相似文献
104.
hVEGF165基因转染后骨髓间充质干细胞蛋白分泌功能及成骨活性的检测 总被引:3,自引:4,他引:3
目的:血管内皮细胞生长因子(vascular endothelial growth factor,VEGF)在血管再生和骨组织再生过程中起着重要的调节作用。观察hVEGF165基因转染的骨髓间充质干细胞分泌VEGF的功能及转染后细胞的成骨活性。
方法:实验于2004—07/2005—12在江苏省血液研究所国家重点实验室完成。①体外分离、培养大鼠骨髓间充质干细胞,传代培养后以1μg PcDNA3.1-hVEGF165:3μL阳离子脂质体Lipofectamine的比例转染,通过免疫组织化学SP方法检测转染后细胞中外源性VEGF的表达。②体外分离、培养大鼠肾微血管内皮细胞,分别加入hVEGF165基因转染48h及1周后细胞上清、空载体转染及未转染组细胞上清,MTT法观察细胞增殖情况,以了解转染后细胞培养上清中VEGF的生物学活性。③测定在正常条件培养和成骨条件培养下,转染后细胞上清中碱性磷酸酶、骨钙素的水平。
结果:①hVEGF165基因转染的骨髓间充质干细胞能成功分泌VEGF蛋白。②hVEGF165基因转染48h组大鼠肾微血管内皮细胞A值高于空载体转染及未转染组(P〈0.05),但低于hVEGF165基因转染1周组。③成骨条件培养下,基因转染组细胞碱性磷酸酶和骨钙素的分泌量明显高于未转染组(P〈0.05);而在正常条件培养下,基因转染组细胞碱性磷酸酶和骨钙素的表达分泌量较低。
结论:①采用基因转染技术可将hVEGF165基因转染到骨髓间充质干细胞中并可有效表达具有生物活性的VEGF,且这种生物学活性呈剂量依赖性。②在成骨条件培养下,转染hVEGF165基因后骨髓间充质干细胞的成骨能力增强。 相似文献
105.
Relationships between thrombopoiesis and erythropoiesis: with studies of the effects of preparations of thrombopoietin and erythropoietin 总被引:2,自引:0,他引:2
The effects of administration of partially purified human urinary erythropoietin and rabbit thrombopoietin, and of endogenously produced erythropoietin and thrombopoietin on both red cell and platelet production were examined in mice. Partially purified thrombopoietin was prepared from rabbit plasma by sequential fractionation with ammonium sulfate precipitation, and DEAE and Sephadex G-100 chromatography. Preparations of thrombopoietin and partially purified human urinary erythropoietin (NIH No. H-11-TaLSL) were administered subcutaneously to normal mice, and the rate of incorporation of selenomethionine-75 Se into platelets was measured as an index of thrombopoietic activity of the infused material. Erythropoietin and thrombopoietin were assayed for erythropoietic activity by measuring the rate of appearance of 59Fe in the red cells of posthypoxic polycythemic mice. Preparations containing thrombopoietin had barely measurable erythropoietic activity, and 7 units of partially purified erythropoietin had little thrombopoietic activity. When endogenous levels of erythropoietin were increased by hypoxia, platelet production was not enhanced. Similarly, increased levels of thrombopoietin, induced in response to thrombocytopenia produced by platelet antiserum, did not alter red cell production. These data suggest that physiologically increased levels of thrombopoietin do not stimulate erythropoiesis, and that physiologically increased levels of erythropoietn do not stimulate thrombopoiesis. However, currently available, partially purified preparations of erythropoietin and thrombopoietin may be capable of stimulating both platelet and red cell production if used in sufficient quantities. 相似文献
106.
Bacterial joint infections in England and Wales: analysis of bacterial isolates over a four year period 总被引:7,自引:2,他引:7
Data from 1158 cases of septic arthritis reported to the Public Health
Laboratory Service (PHLS) Communicable Disease Control Centre (CDSC) from
England and Wales over a 4 yr period (January 1990 December 1993) are
presented. Reports where a bacterial organism was isolated from synovial
fluid, or where an organism was isolated from blood cultures where a
diagnosis of septic arthritis was reported, were examined. Reports of
infection were more common in children (12.7% of infections were in the
under 10 age group) and the elderly (54.7% aged 60 or over), and were
higher in males in all age groups except in the elderly. The most common
causative organisms remain staphylococcal and streptococcal species,
comprising 40.6% (470) and 28% (324) of cases, respectively. The most
common streptococci seen were Streptococcus pneumoniae and Lancefield group
A beta-haemolytic Streptococcus organisms, 60.8% (197/324), although group
B, C and G organisms accounted for 33.6% of streptococcal isolates
(109/324). Haemophilus influenzae septic arthritis is not exclusive to
children as 23.2% (16- 69) of cases occurred over the age of 15. A total of
48% (635) of isolates were identified from both synovial fluid and blood
cultures, 32.6% (378) from joint fluid alone and 12.5% (146) from blood
cultures. Although this study excludes cases of septic arthritis where no
organism was isolated, it presents important bacteriological information
from a large number of isolates from England and Wales over a 4 yr period.
Risk factors identified include a joint prosthesis, joint
disease/connective tissue disorder. immunosuppression and diabetes.
相似文献
107.
Absence of human T-cell lymphotropic virus type I coinfection in human immunodeficiency virus-infected hemophilic men 总被引:2,自引:0,他引:2
Concern for transmission of human T-cell lymphotropic virus, type 1 (HTLV-1) infection to recipients of infected cellular blood products has prompted development of tests to eliminate blood units with HTLV-I antibodies. Most hemophilic men from the United States became infected with human immunodeficiency virus (HIV) before HIV donor screening and before blood products were processed to inactivate the virus. To assess whether these men might also be infected with HTLV-I, we examined the HTLV-I antibody status of 127 factor VIII (hemophilia A) recipients and 71 factor IX (hemophilia B) recipients. One HIV-seronegative and four HIV-seropositive persons were HTLV-I reactive by enzyme-linked immunosorbent assay (ELISA). Four of five ELISA-reactive serum samples were negative by HTLV-I immunoblot assay (IB); 1 reactive and 1 borderline reactive serum were indeterminate on IB (p19 reactivity), but negative by radioimmunoprecipitation assay (RIPA). Peripheral blood mononuclear cells from one patient with indeterminate HTLV-I IB were negative for HTLV-I genomic sequences by polymerase chain reaction. The other indeterminate patient's serum antibody pattern was stable over a 2-year period, suggesting this was not an instance of early HTLV-I seroconversion. These results reaffirm the safety of factor components in the United States with regard to HTLV-I but emphasize the importance and need for further testing of reactive HTLV-I ELISA results with a second more specific technique. 相似文献
108.
109.
110.
Transformed T lymphocytes infected by a novel isolate of human T cell leukemia virus type II 总被引:1,自引:0,他引:1
Chorba TL; Brynes R; Kalyanaraman VS; Telfer M; Ramsey R; Mawle A; Palmer EL; Chen AT; Feorino P; Evatt BL 《Blood》1985,66(6):1336-1342
Human T cell leukemia virus type II (HTLV-II) has been isolated from a patient (Mo) with features of leukemic reticuloendotheliosis (LRE) and from a patient with acquired immunodeficiency syndrome (AIDS). We have obtained another isolate of HTLV-II from a patient (CM) with severe hemophilia A, pancytopenia, and a 14-year history of staphylococcal and candidal infections but no evidence of T cell leukemia/lymphoma, AIDS, or LRE. Fresh mononuclear cells and cultured lymphocytes from CM express retroviral antigens indistinguishable by molecular criteria from HTLV-IIMo. Leukocyte cultures from CM yield hyperdiploid (48,XY, +2, +19) continuous lymphoid lines; human fetal cord blood lymphocytes (CBL) are transformed by cocultivation with these CM cell cultures but retain normal cytogenetic constitution. Electron microscopic examination of the CM cultures and transformed CBL reveals budding of extracellular viral particles, intracellular tubuloreticular structures, and viral particles contained within intracellular vesicles. CM cell cultures and the transformed CBL do not require exogenous interleukin 2, have T cell cytochemical features and mature T helper phenotypes, and exhibit minimal T helper and profound T suppressor activity on pokeweed mitogen-stimulated differentiation of normal B cells. These characteristics, which are similar to those observed with the first HTLV-II isolate, may represent properties of all HTLV-II-infected T cells. 相似文献