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1.
Differentiation of pancreatic epithelial progenitor cells into hepatocytes following transplantation into rat liver 下载免费PDF全文
Mariana D. Dabeva Seong-Gyu Hwang Srinivasa Rao G. Vasa Ethel Hurston Phyllis M. Novikoff Douglas C. Hixson Sanjeev Gupta David A. Shafritz 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(14):7356-7361
The ability to identify, isolate, and transplant progenitor cells from solid tissues would greatly facilitate the treatment of diseases currently requiring whole organ transplantation. In this study, cell fractions enriched in candidate epithelial progenitor cells from the rat pancreas were isolated and transplanted into the liver of an inbred strain of Fischer rats. Using a dipeptidyl dipeptidase IV genetic marker system to follow the fate of transplanted cells in conjunction with albumin gene expression, we provide conclusive evidence that, after transplantation to the liver, epithelial progenitor cells from the pancreas differentiate into hepatocytes, express liver-specific proteins, and become fully integrated into the liver parenchymal structure. These studies demonstrate the presence of multipotent progenitor cells in the adult pancreas and establish a role for the liver microenvironment in the terminal differentiation of epithelial cells of foregut origin. They further suggest that such progenitor cells might be useful in studies of organ repopulation following acute or chronic liver injury. 相似文献
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3.
Reed Jon A.; Nador Roland G.; Spaulding David; Tani Yoichi; Cesarman Ethel; Knowles Daniel M. 《Blood》1998,91(10):3825-3832
4.
Sputum Cytokine Levels in Patients with Pulmonary Tuberculosis as Early Markers of Mycobacterial Clearance 下载免费PDF全文
Rodrigo Ribeiro-Rodrigues Tatiana Resende Co John L. Johnson Fabiola Ribeiro Moises Palaci Ricardo T. S Ethel L. Maciel Fausto E. Pereira Lima Valderio Dettoni Zahra Toossi W. Henry Boom Reynaldo Dietze Jerrold J. Ellner Christina S. Hirsch 《Clinical and Vaccine Immunology : CVI》2002,9(4):818-823
Sputum and serum from patients with active pulmonary tuberculosis (TB), healthy purified protein derivative-positive adults, and patients with bacterial pneumonia were collected to simultaneously assess local immunity in the lungs and peripheral blood. To determine whether cytokine profiles in sputum from TB patients and control subjects were a reflection of its cellular composition, cytospin slides were prepared in parallel and assessed for the presence of relative proportions of epithelial cells, neutrophils, macrophages, and T cells. Gamma interferon (IFN-γ) in sputum from TB patients was markedly elevated over levels for both control groups. With anti-TB therapy, IFN-γ levels in sputum from TB patients decreased rapidly and by week 4 of treatment were comparable to those in sputum from controls. Further, IFN-γ levels in sputum closely followed mycobacterial clearance. Although detected at fourfold-lower levels, IFN-γ immunoreactivities in serum followed kinetics in sputum. TNF-α, interleukin 8 (IL-8) and IL-6 also were readily detected in sputum from TB patients at baseline and responded to anti-TB therapy. In contrast to IFN-γ, however, TNF-α and IL-8 levels also were elevated in sputum from pneumonia controls. These data indicate that sputum cytokines correlate with disease activity during active TB of the lung and may serve as potential early markers for sputum conversion and response to anti-TB therapy. 相似文献
5.
Herschel Sidransky Ethel Verney Challakonda N. Murty 《Experimental and molecular pathology》1981,35(1):124-136
Female inbred Buffalo rats bearing intrahepatically transplanted hepatoma 5123 were subjected intraperitoneally to the acute administration of hypertonic NaCl or CCl4 followed by a tube-feeding of l-tryptophan. The responses in terms of changes in polyribosomal aggregation and protein synthesis (in vitro) of host liver and hepatoma were evaluated. While treatment with hypertonic NaCl or CCl4 caused disaggregation of polyribosomes and inhibition of protein synthesis in both host liver and hepatoma, the subsequent administration of tryptophan caused some improvement in both parameters in host liver but not in hepatoma. Administration of hypertonic NaCl alone caused a decrease in [14C]orotate incorporation into poly(A)-mRNA of host liver and hepatoma, whereas administration of tryptophan after hypertonic NaCl caused a significant improvement in host liver alone. Following the tryptophan administration, the activities of nuclear DNA-dependent RNA polymerases I and II, and of nuclear-envelope nucleoside triphosphatase, as well as labeled nuclear RNA release in vitro were slightly elevated in host liver but not in hepatoma. Tryptophan-related compounds, 5-hydroxy-dl-tryptophan, 5-fluorotryptophan, indole, and 3-hydroxyanthranilic acid, when administered in place of l-tryptophan, did not appreciably affect polyribosomal aggregation or protein synthesis in vitro in host liver or hepatoma. 相似文献
6.
Prevalence rates and psychosocial characteristics associated with depression in pregnancy and postpartum in Maltese women 总被引:4,自引:0,他引:4
BACKGROUND: Investigators have commented on the apparent high prevalence of psychiatric symptoms in pregnancy. In Malta there is lack of epidemiological data and therefore, the prevalence of depression during pregnancy and at 8 weeks postpartum among a community sample of Maltese women was carried out. METHOD: A random sample of 239 pregnant women were interviewed at booking using a detailed sociodemographic history, the revised version of the clinical interview schedule (CIS-R) and Maltese translation of the Edinburgh postnatal depression scale (EPDS). The CIS-R was again administered over the phone at 36 weeks and the EPDS sent by post. At 8 weeks postpartum, the CIS-R, modified version of the social maladjustment schedule and the EPDS were again administered to 95.8% of women. RESULTS: The point prevalence of depression meeting ICD-10 research criteria was 15.5% at booking, 11.1% in the third trimester and 8.7% postpartum of which only 3.9% had an onset since delivery. CONCLUSIONS: The low rate of new onset postpartum depression compared with other studies in our sample may be attributable to the social support available to women living in a cohesive Catholic island community. LIMITATION: The follow-up was limited to 8 weeks postpartum. No control group was used to compare the prevalence of depression in women who did not recently have a baby. 相似文献
7.
Spectrum of Kaposi's sarcoma-associated herpesvirus,or human herpesvirus 8, diseases 总被引:20,自引:0,他引:20 下载免费PDF全文
Human herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma-associated herpesvirus (KSHV), discovered in 1994, is a human rhadinovirus (gamma-2 herpesvirus). Unlike other human herpesviruses (herpes simplex virus, Epstein-Barr virus, varicella-zoster virus, cytomegalovirus, HHV-6, and HHV-7), it is not widespread in the general population and has many unique proteins. HHV-8 is strongly associated with all subtypes of Kaposi's sarcoma (KS), multicentric Castleman's disease, and a rare form of B-cell lymphoma, primary effusion lymphoma. In addition, HHV-8 DNA sequences have been found in association with other diseases, but the role of the virus in these diseases is largely unconfirmed and remains controversial. The seroprevalence of HHV-8, based on detection of latent and lytic proteins, is 2 to 5% in healthy donors except in certain geographic areas where the virus is endemic, 80 to 95% in classic KS patients, and 40 to 50% in HIV-1 patients without KS. This virus can be transmitted both sexually and through body fluids (e.g., saliva and blood). HHV-8 is a transforming virus, as evidenced by its presence in human malignancies, by the in vitro transforming properties of several of its viral genes, and by its ability to transform some primary cells in culture. It is not, however, sufficient for transformation, and other cofactors such as immunosuppressive cytokines are involved in the development of HHV-8-associated malignancies. In this article, we review the biology, molecular virology, epidemiology, transmission, detection methods, pathogenesis, and antiviral therapy of this newly discovered human herpesvirus. 相似文献
8.
James R. Wright Karen A. Samson Ethel Cooper-Rosen D. Christie Riddell 《Fetal and pediatric pathology》1998,18(2):151-156
Breus' mole, a massive subchorionic placental hematoma, is associated with intrauterine growth retardation and second trimester stillbirth. It is relatively rare and, hence, is poorly understood. Initially, Breus' mole was thought to be a consequence of fetal demise, but subsequent observations in placentas of live - born infants as well as identification in prenatal ultrasounds prior to fetal demise discredited this tenet. A number of theories have been proposed to explain the etiology of Breus' mole; some suggest that it is a fetal hemorrhage, others claim a maternal thombosis. However, these theories are based entirely on speculation, and it is unclear from the literature whether the source of the hematoma is maternal or fetal. A macerated female fetus was delivered of a 31 - year - old G1 P0 woman at 24 weeks' gestation; the autopsy showed only marked intrauterine growth retardation while placental examination showed a massive subchorionic hematoma. DNAs extracted from portions of the fresh hematoma, placental villi (i.e., fetal tissue), and maternal blood were compared using molecular analyses. Polymerase chain reaction using primers that identify highly polymorphic loci distinguished fetal from maternal DNAs. This is the first case of Breus' mole analyzed using molecular methods; the source in this case is definitively maternal, suggesting the etiology is maternal thrombosis. 相似文献
9.
Abbreviated chemotherapy with fludarabine followed by tositumomab and iodine I 131 tositumomab for untreated follicular lymphoma. 总被引:4,自引:0,他引:4
John P Leonard Morton Coleman Lale Kostakoglu Amy Chadburn Ethel Cesarman Richard R Furman Michael W Schuster Ruben Niesvizky Daniel Muss Jennifer Fiore Stewart Kroll George Tidmarsh Shankar Vallabhajosula Stanley J Goldsmith 《Journal of clinical oncology》2005,23(24):5696-5704
PURPOSE: To evaluate the safety and efficacy of a sequential chemotherapy plus radioimmunotherapy (RIT) regimen in previously untreated follicular non-Hodgkin's lymphoma. PATIENTS AND METHODS: Thirty-five patients received an abbreviated course (three cycles) of fludarabine followed 6 to 8 weeks later by tositumomab and iodine I 131 tositumomab. RESULTS: After fludarabine, 31 (89%) of 35 patients responded, with three (9%) of 31 patients achieving a complete response (CR). After the full regimen of fludarabine and iodine I 131 tositumomab, all 35 patients responded; 30 (86%) of 35 patients achieved CR, and five (14%) of 35 achieved partial response. After a median follow-up of 58 months, the median progression-free survival (PFS) had not been reached (95% CI, 27 months to not reached), but it will be at least 48 months. The 5-year estimated PFS rate is 60%. Baseline Follicular Lymphoma International Prognostic Index (FLIPI) was significantly associated (P = .003) with PFS. Five of six patients with more than 25% bone marrow involvement at baseline achieved adequate bone marrow cytoreduction to receive standard-dose iodine I 131 tositumomab. Ten (77%) of 13 patients with baseline bone marrow Bcl-2 positivity demonstrated molecular remissions at month 12. Toxicities were manageable and principally hematologic. Two (6%) of 35 patients developed human antimurine antibodies (HAMA) after RIT. CONCLUSION: Use of abbreviated fludarabine before iodine I 131 tositumomab can reduce bone marrow involvement, when needed, to allow the use of RIT and can suppress HAMA responses. This sequential treatment regimen is highly effective as front-line therapy for follicular lymphoma, particularly for low- or intermediate-risk FLIPI patients. 相似文献
10.