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71.
Innovations in design of a dedicated breast scanner resulted in automation of the scanning process, the production of high resolution images of the whole breast and an efficient mode of image review. The results of clinical evaluation of the prototype of this breast scanner investigating normal breasts as well as benign and malignant breast lesions are presented.  相似文献   
72.
73.
Oral Diseases (2010) 17 , 33–44 Objectives: To study the natural aetiopathology of jaw atrophy after tooth loss, unaltered by prosthetic procedures, an historical population without modern dental treatment was examined. Methods: Based on the hypothesis that there are predictable changes in shape during jaw‐atrophy, frequency and degree of atrophy as well as clinical aspects of bone quality and resorption were determined in the skeletal remains of 263 individuals. The potential association between age and frequency/severity of atrophy was analysed. Results: Atrophy in at least one jaw segment was present in 45.2% of the analysed jaw specimens. The residual ridge underwent a series of changes in shape and height following the pattern of resorption described for modern populations. The severity of these alterations was associated with the age of the individual and the region within the jaw. Atrophy was frequently related to structural degradation of the covering cortical layer. Conclusions: These findings prove that atrophy of the jaw evidently does occur, displaying similar patterns of resorption in a population without modern prosthetics, where the negative effect of ill‐fitting dentures is excluded. The basic information about alterations of shape and the cortical layer covering the residual crest might help to provide a deeper insight into aetiopathological mechanisms of this common oral disease.  相似文献   
74.
Immediate treatment for asymptomatic, low-tumor burden follicular lymphoma (FL) has not shown an overall survival benefit over “watch and wait” (W/W) strategy. We estimated incidence of treatment initiation at specific time points and assessed its association with the presence of any criteria such as GELF, BNLI, GITMO at diagnosis. FL patients managed by W/W strategy were identified from the Molecular Epidemiology Resource (MER) of the University of Iowa/Mayo Clinic Lymphoma SPORE between 2002 and 2015. Cumulative incidence estimates of treatment initiation were calculated using transformation (as the first event) and death as competing risks. 401 FL patients were identified on W/W strategy. At a median follow-up of 8 years, 256 (64%) initiated treatment. For patients on the W/W strategy for 5 years, the likelihood of treatment initiation in the next 5 years was 12% compared to 43% at diagnosis unlike transformation rates which remained steady. Patients with any of popular treatment criteria at diagnosis did not have increased therapy initiation rates (44% vs. 42%) during the first 5 years or lymphoma-related death rates at 10 years (6% vs. 7%). Identifying biological differences in patients with early vs. late or no progression is a critical next step in understanding outcomes in W/W patients.Subject terms: Disease-free survival, B-cell lymphoma  相似文献   
75.
Peripheral T-cell lymphomas (PTCLs) are a heterogenous group of aggressive non-Hodgkin''s lymphomas that are incurable in the majority of patients with current therapies. Outcomes associated with anthracycline-based therapies are suboptimal, but remain the standard of care for most patients, even though the benefits of this approach remain uncertain. This study retrospectively examined outcomes in a cohort of North American PTCL patients treated with both anthracycline- and nonanthracycline-containing regimens. The incorporation of anthracycline-containing regimens was associated with improved progression-free survival (PFS) and overall survival (OS). Patients treated with nonanthracycline-containing regimens were more likely to have high-risk features and were less likely to undergo high-dose therapy and stem cell transplantation. However, anthracycline use remained an independent predictor of improved PFS and OS when adjusting for these confounding variables. Anthracycline-based regimens and consolidation with high-dose therapy and autologous stem cell transplantation in appropriately selected patients remains a viable option for patients unable to participate in a clinical trial. Long-term disease-free survival is not optimal, highlighting the need for an improved understanding of disease pathogenesis, and the development of novel therapeutic strategies.  相似文献   
76.
Vitreoretinal lymphoma (VRL) management remains a challenge. We present 72 patients with VRL, diagnosed at Mayo Clinic between 1990-2018. Three nondiffuse large B-cell lymphoma (DLBCL) histology cases were excluded. Among 69 DLBCL, 33 patients had primary VRL (PVRL), 18 concurrent intraocular and central nervous system (CNS) or systemic disease and 18 secondary VRL. Patients received intraocular chemotherapy (intraocular injections of rituximab or metothrexate or steroids or in combination), radiotherapy, systemic or combined systemic plus intraocular treatment in 9, 10, 35, and 15 cases, respectively. Among primary and concurrent VRL, median failure free survival (FFS), CNS relapse-free survival (CNS-RFS) and overall survival (OS) were: 1.8, 4.9, and 4.1 years, respectively; among PVRL, median FFS, CNS-RFS, and OS were: 2.6 year, Not Reached and 9.3 year, respectively. No CNS relapse occurred beyond 4 years in PVRL. Median OS for patients diagnosed between 1990 and 1999 vs between 2000 and 2018 was 1.5 vs 9.4 years, respectively (P = .0002). OS was significantly higher in PVRL, as compared with concurrent VRL (P = .04). Previous immunosuppression and poor performance status were predictive of worse outcome. In PVRL, a combined systemic and intraocular therapy showed higher FFS (P = .002) and CNS-RFS (P = .003), but no differences in OS. Among 18 secondary VRL, at a median follow-up of 1.1 year after vitreoretinal relapse, median FFS and OS were 0.3 and 1.3 years. An improvement in survival of VRL has been observed over the decades. PVRL should undergo combined systemic and intraocular chemotherapy to prevent CNS progression.  相似文献   
77.
The World Health Organization classification of non‐Hodgkin lymphoma (NHL) was introduced in 2001. However, its incorporation into clinical practice is not well‐described. We studied the distribution of NHL subtypes in adults diagnosed from 1998 to 2011, evaluated time trends, geo‐demographic correlates, and changes in 5‐year overall survival (OS). We obtained data prospectively collected by the National Cancer Data Base, which covers 70% of US cancer cases. There were 596,476 patients diagnosed with NHL. The major subtypes were diffuse large B‐cell (32.5%), chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL; 18.6%), follicular (17.1%), marginal zone (8.3%), mantle cell (4.1%), peripheral T‐cell not‐otherwise‐specified (1.7%), Burkitt (1.6%), hairy cell (1.1%), lymphoplasmacytic (1.1%), and NHL not‐otherwise‐specified (10.8%). Over the study period, the proportion of NHL not‐otherwise‐specified declined by half, while marginal zone lymphoma doubled. The distribution of major and rare NHL subtypes varied according to demographics but less so geographically or by type of treatment facility. We noted several novel findings among Hispanics (lower proportion of CLL/SLL, but higher Burkitt lymphoma and nasal NK/T‐cell lymphoma), Asians (higher enteropathy‐associated T‐cell and angioimmunoblastic T‐cell lymphomas), Blacks (higher hepatosplenic T‐cell lymphoma), and Native Americans (similar proportions of CLL/SLL and nasal NK/T‐cell lymphoma as Asians). With the exception of peripheral T‐cell not‐otherwise‐specified and hairy cell leukemia, 5‐year OS has improved for all the major NHL subtypes. Am. J. Hematol. 90:790–795, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
78.
Natural killer (NK)-like T cells are major histocompatibility complex- unrestricted cytotoxic T cells that are surface CD3-positive, express NK-cell antigens, and rearrange their T-cell receptor. Most neoplasms arising from this T-cell subpopulation have been a chronic lymphoproliferative disease referred to as T-large granular lymphocyte (LGL) leukemia. Only 10 NK-like T-cell lymphomas have been described in detail previously; this study presents the clinicopathologic features of six others and distinguishes these lymphomas from T-LGL leukemia. All patients presented with B-symptoms and often had marked hepatosplenomegaly without significant peripheral lymphadenopathy. Four of the six patients were immunosuppressed. All had CD3, CD8, CD56- positive tumors, presumably of hepatosplenic (n = 3), intestinal (n = 1), pulmonary (n = 1), or nodal (n = 1) origin. Three patients had lymphomatous bone marrow infiltrates, and four had peripheral blood involvement by neoplastic large lymphocytes, some of which had a blastic appearance or resembled virocytes. Azurophilic granules, ultrastructurally corresponding to cytoplasmic dense core and/or double density granules, were seen in all cases. T-cell clonality was shown in five tumors by Southern blot analysis, and three had abnormal karyotypes. Two untreated patients died 20 days after presentation, and three patients who received combination chemotherapy died within 5 months of presentation. One patient remains in complete remission 22 months after treatment. These findings suggest NK-like T-cell lymphomas are aggressive, are clinicopathologically distinct from T-LGL leukemia, and should be in the differential diagnosis of extranodal T-cell lymphoproliferations, including those in immunosuppressed patients. Furthermore, the LGL morphology, phenotype, and tissue distribution of some NK-like T-cell lymphomas suggest they arise from thymic- independent T cells of the hepatic sinusoids and intestinal mucosa.  相似文献   
79.
LaDuca  FM; Bettigole  RE; Bell  WR; Robson  EB 《Blood》1986,68(4):927-937
The contribution of von Willebrand factor (vWF)-platelet binding to platelet-collagen interaction was examined in vitro. The binding of vWF to platelets was mediated and regulated by ristocetin. Subthreshold concentrations of ristocetin (less than or equal to 1 mg/mL), insufficient to cause ristocetin-induced platelet aggregation (RIPA), were added to platelet-rich plasma (PRP) prior to the addition of collagen. The collagen-induced platelet aggregation (CIPA) was modified by ristocetin and the degree of alteration was dependent on the ristocetin concentration. Response as a function of ristocetin concentration was designated the Collagen-Platelet Aggregation Response (CoI-PAR). In normal PRP the CoI-PAR was a progressive inhibition followed by decreasing inhibition and then an enhanced response. The enhanced response occurred over a narrow range of ristocetin concentrations (0.8 to 1.0 mg/mL). In the absence of vWF (severe von Willebrand's disease, Type I, vWF less than 1%) the CoI-PAR was a progressive, eventually complete inhibition with no enhanced response (with ristocetin concentrations up to 3.0 mg/mL). With addition of vWF to this PRP an enhanced response was observed at a ristocetin concentration inversely proportional to the vWF level. PRP from a patient with severe Hemophilia A showed a response within the normal range. Subthreshold ristocetin did not cause plasma protein precipitation or platelet release of 3H-serotonin, nor induce micro platelet aggregate formation. Digestion of platelet membrane glycoproteins (GP(s] with chymotrypsin demonstrated that upon removal of GPI, RIPA was absent, CIPA retained and the CoI-PAR was progressive inhibition, with no enhancement. With removal of GPs I, II, and III, RIPA, CIPA, and the CoI-PAR were absent. A dose-response 125I-vWF- platelet binding occurred with increasing ristocetin concentrations which was unchanged by the addition of collagen. These results demonstrated that ristocetin-platelet association inhibited CIPA, and vWF-platelet binding enhanced platelet-collagen adhesion and platelet aggregation. The in vitro-enhanced CIPA represents a vWF-dependent aggregation of sufficient magnitude to overcome the inhibitory effect of ristocetin. These studies demonstrate an influential interaction of ristocetin, vWF, and collagen with the platelet membrane and imply an important hemostatic contribution of vWF-platelet binding in platelet- collagen interaction.  相似文献   
80.
Okamoto  S; Olson  AC; Berdel  WE; Vogler  WR 《Blood》1988,72(5):1777-1783
Ether lipids (EL) and hyperthermia have been shown to possess a relatively selective cytotoxicity to leukemic cells. In this study, the combined effects of EL (ET-18-OCH3, ET-16-NHCOCH3, or BM 41.440) and hyperthermia on the growth of hematopoietic progenitors, myeloid leukemic cell lines, and leukemic cells obtained from patients with acute myeloid leukemia (AML) were examined to determine if this combination resulted in a greater selective killing of leukemic cells than that achieved by either EL or heat alone. When the cells were treated simultaneously with EL (50 micrograms/mL) and hyperthermia (42 degrees C) for one hour, the killing of leukemic cell line cells was enhanced considerably. Among the three EL, however, the combination of ET-18-OCH3 and heat seemed to be the most cytotoxic to leukemic cell line cells with no effect on the growth of hematopoietic progenitors. An increase in the duration of treatment with ET-18-OCH3 to four hours with heat added during the last hour resulted in a further reduction of leukemic cell line cells while sparing 50% of hematopoietic progenitors after cryopreservation. The combined treatment with ET-18-OCH3 and heat also inhibited the growth of leukemic progenitors obtained from AML patients by 97% to 100%. These data indicate that the combined treatment with EL and hyperthermia might offer an efficient means to eliminate myeloid leukemic cells in vitro.  相似文献   
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