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21.
Archana Swami Michaela R. Reagan Pamela Basto Yuji Mishima Nazila Kamaly Siobhan Glavey Sufeng Zhang Michele Moschetta Dushanth Seevaratnam Yong Zhang Jinhe Liu Masoumeh Memarzadeh Jun Wu Salomon Manier Jinjun Shi Nicolas Bertrand Zhi Ning Lu Kenichi Nagano Roland Baron Antonio Sacco Aldo M. Roccaro Omid C. Farokhzad Irene M. Ghobrial 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(28):10287-10292
Bone is a favorable microenvironment for tumor growth and a frequent destination for metastatic cancer cells. Targeting cancers within the bone marrow remains a crucial oncologic challenge due to issues of drug availability and microenvironment-induced resistance. Herein, we engineered bone-homing polymeric nanoparticles (NPs) for spatiotemporally controlled delivery of therapeutics to bone, which diminish off-target effects and increase local drug concentrations. The NPs consist of poly(d,l-lactic-co-glycolic acid) (PLGA), polyethylene glycol (PEG), and bisphosphonate (or alendronate, a targeting ligand). The engineered NPs were formulated by blending varying ratios of the synthesized polymers: PLGA-b-PEG and alendronate-conjugated polymer PLGA-b-PEG-Ald, which ensured long circulation and targeting capabilities, respectively. The bone-binding ability of Ald-PEG-PLGA NPs was investigated by hydroxyapatite binding assays and ex vivo imaging of adherence to bone fragments. In vivo biodistribution of fluorescently labeled NPs showed higher retention, accumulation, and bone homing of targeted Ald-PEG-PLGA NPs, compared with nontargeted PEG-PLGA NPs. A library of bortezomib-loaded NPs (bone-targeted Ald-Bort-NPs and nontargeted Bort-NPs) were developed and screened for optimal physiochemical properties, drug loading, and release profiles. Ald-Bort-NPs were tested for efficacy in mouse models of multiple myeloma (MM). Results demonstrated significantly enhanced survival and decreased tumor burden in mice pretreated with Ald-Bort-NPs versus Ald-Empty-NPs (no drug) or the free drug. We also observed that bortezomib, as a pretreatment regimen, modified the bone microenvironment and enhanced bone strength and volume. Our findings suggest that NP-based anticancer therapies with bone-targeting specificity comprise a clinically relevant method of drug delivery that can inhibit tumor progression in MM.The incidence of bone metastasis is common in 60–80% of cancer patients (1). During bone metastasis, cancer cells induce a sequence of changes in the microenvironment such as secreting cytokines to increase the activity of osteoclasts via the parathyroid hormone-related protein (PTHrP), receptor activator of nuclear factor-κB ligand (RANKL), and interleukin-6 (IL-6), resulting in increased bone resorption and secretion of growth factors from the bone matrix (2). This creates a “vicious cycle” of bone metastasis, where bone marrow becomes packed with cancer cells that develop resistance to conventional chemotherapy, and leads to devastating consequences of bone fractures, pain, hypercalcaemia, and spinal cord and nerve compression syndromes (2, 3). Multiple myeloma (MM) is a plasma cell cancer that proliferates primarily in bone marrow and causes osteolytic lesions (1). Antiresorption agents, such as bisphosphonates, may alleviate bone pain, but they are ineffective at inducing bone healing or osteogenesis in MM patients (4).Bortezomib is a proteasome inhibitor that has shown marked antitumor effects in patients with MM. Proteasome inhibitors, such as bortezomib, are also effective at increasing bone formation, both preclinically and clinically (5–9). However, the major drawback of bortezomib use in early stages of MM development is its toxicity, specifically, peripheral neuropathy (5). Therefore, we aimed to develop a method to deliver bortezomib with decreased off-target side effects by using bone-specific, bortezomib-loaded nanoparticles (NPs). The NP system was based on biodegradable, biocompatible, and Food and Drug Administration (FDA)-approved components, which are both clinically and translationally relevant. NPs derived from poly(d,l-lactic-co-glycolic acid) (PLGA), a controlled release polymer system, are an excellent choice because their safety in the clinic is well established (10, 11). Polyethylene glycol (PEG)-functionalized PLGA NPs are especially desirable as PEGylated polymeric NPs have significantly reduced systemic clearance compared with similar particles without PEG (12, 13). A number of FDA-approved drugs in clinical practice use PEG for improved pharmaceutical properties such as enhanced circulation in vivo (12, 13). To target NPs to bone [rich in the mineral hydroxyapatite (HA)], the calcium ion-chelating molecules of bisphosphonates represent a promising class of ligands (14). Bisphosphonates, upon systemic administration, are found to deposit in bone tissue, preferentially at the high bone turnover sites, such as the metastatic bone lesions, with minimal nonspecific accumulation (14) and were used herein to deliver NPs to the bone.A few systems explored for MM treatment have been tested in vitro including the following: (i) snake venom and silica NPs (15); (ii) thymoquinone and PLGA-based particles (16); (iii) curcumin and poly(oxyethylene) cholesteryl ether (PEG-Chol) NPs (17), polyethylenimine-based NPs for RNAi in MM (18), paclitaxel-Fe3O4 NPs (19), and liposomes (20). However, none of the above-mentioned systems have aimed to manipulate the bone marrow microenvironment rather than the myeloma cells directly (21). To date, there are no reports of using bone-targeted, controlled release, polymeric NPs with stealth properties for MM therapy. In this study, we designed NPs bearing three main components: (i) a targeting element that can selectively bind to bone mineral; (ii) a layer of stealth (PEG) to minimize immune recognition and enhance circulation; and (iii) a biodegradable polymeric material, forming an inner core, that can deliver therapeutics and/or diagnostics in a controlled manner. In this study, the physicochemical properties of a range of NPs was investigated (including NP size, charge, targeting ligand density, drug loading, and drug release kinetics) and an optimal formulation with ideal properties and maximal drug encapsulation was used for in vivo efficacy studies. We fine-tuned the NP targeting ligand density to optimize its bone-binding ability and further investigated its application for targeting myeloma in the bone microenvironment. We believe our NP system has the potential to increase drug availability by improving pharmacokinetics and biodistribution that can provide bone microenvironment specificity, which may increase the therapeutic window and most certainly decrease the off-target effects (12, 13). 相似文献
22.
目的数值模拟抗血管生成因子Angiostatin和Endostatin对肿瘤血管生成的影响。方法建立肿瘤内外血管生成的二维离散数学模型。模型耦合两种抗血管生成因子Angiostatin和Endostatin的抑制效应,数值模拟在促血管生成因子诱导下肿瘤微血管网生成,讨论血管生成抑制因子的影响。结果抗血管生成因子Angiostatin对肿瘤内外血管网络生成的速度和成熟度有抑制作用。抗血管生成因子Angiostatin和Endostatin耦合作用时,在肿瘤血管生成的早期有明显的抑制效应;在肿瘤血管生成的中后期,它们可以降低肿瘤血管化程度。结论本文模型能够较好的模拟抗血管生成因子Angiostatin和Endostatin对内皮细胞迁移和增殖的抑制作用。 相似文献
23.
Mitsugi Shimoda Rafik M Ghobrial Ian C Carmody Dean M Anselmo Douglas G Farmer Hasan Yersiz Pauline Chen Sherfield Dawson Francisco Durazo Steve Han Leonard I Goldstein Sammy Saab Jonathan Hiatt Ronald W Busuttil 《Liver transplantation》2004,10(12):1478-1486
The efficacy of orthotopic liver transplantation (OLT) for hepatocellular carcinoma (HCC) associated with hepatitis C virus (HCV) is not well defined. This study examines the variables that may determine the outcome of OLT for HCC in HCV patients. From 1990 to 1999, 463 OLTs were performed for HCV cirrhosis. Of these patients, 67 with concurrent HCC were included in the study. Univariate and multivariate analyses considered the following variables: gender, pTNM stage, tumor size, number of nodules, vascular invasion, incidental tumors, adjuvant chemotherapy, preoperative chemoembolization, alpha-fetoprotein (AFP) tumor marker, lobar distribution, and histological grade. Overall OLT survival of HCV patients diagnosed with concomitant HCC was significantly lower when compared to patients who underwent OLT for HCV alone at 1, 3, and 5 years (75%, 71%, and 55% versus 84%, 76%, and 75%, respectively; P < 0.01). Overall survival of patients with stage I HCC was significantly better than patients with stage II, III, or IV (P < .05). Eleven of 67 patients developed tumor recurrence. Sites of recurrence included transplanted liver (5), lung (5), and bone (1). Twenty-four of 67 patients (36%) died during the follow-up time. Causes of deaths included recurrent HCC in 8 of 24 patients (12%) and recurrent HCV in 3 of 24 patients (4.5%), whereas 13 (19.5%) patients died from causes that were unrelated to HCV or HCC. Both univariate and multivariate analysis demonstrated that pTNM status (I versus II, III, and IV; P < .05) was a reliable prognostic indicator for patient survival. Presence of vascular invasion (P = .0001) and advanced pTNM staging (P = .038) increased risk of recurrence. Multivariate analysis showed that pretransplant chemoembolization and adjuvant chemotherapy reduced risk of death after OLT in HCC recipients. In conclusion, this study demonstrates the effectiveness of OLT for patients with HCC in a large cohort of chronic HCV patients. Advanced tumor stage, and particularly vascular invasion, are poor prognostic indicators for tumor recurrence. Early pTNM stage, adjuvant chemotherapy, and preoperative chemoembolization were associated with positive outcomes for patients who underwent OLT for concomitant HCV and HCC. 相似文献
24.
George M. Ghobrial Nathan H. Lebwohl Barth A. Green Joseph P. Gjolaj 《The spine journal》2017,17(11):1594-1600
Background Context
Prior reports have compared posterior column osteotomies with pedicle subtraction osteotomies in terms of utility for correcting fixed sagittal imbalance in adolescent patients with deformity. No prior reports have described the use of multilevel Smith-Petersen Osteotomies (SPOs) alone for surgical correction in the adult spinal deformity (ASD) population.Purpose
The study aimed to determine the utility of multilevel SPOs in the management of global sagittal imbalance in ASD patients.Study Design/Setting
This is a retrospective observational study at a single academic center.Patient Sample
The sample included 85 ASD patients.Outcome Measures
This is a radiographic outcomes cohort study.Methods
The radiographs of 85 ASD patients were retrospectively evaluated before and after long-segment (>5 spinal levels) fusion and multilevel SPO (≥3 levels) for sagittal imbalance correction. The number of osteotomies, correction in regional lumbar lordosis (LL), and correction per osteotomy was evaluated. Independent predictors of correction per SPO were evaluated with a hierarchical linear regression analysis.Results
Eighty-five patients (mean age: 67.5±11 years) were identified with ASD (372 SPOs). The mean preoperative sagittal vertical axis (SVA) and T1 pelvic angle (TPA) were 8.16±6.75?cm and 25°±13.23°, respectively. The mean postoperative central sacral vertical line (CSVL) and SVA were 0.67±0.70?cm and 1.29±5.41?cm, respectively. The mean improvement in SVA was 6.29?cm achieved with a correction of approximately 5.05° per SPO. The mean LL restoration was 20.3°±13.9°, and 33(39%) patients achieved a final pelvic incidence minus lumbar lordosis (PI-LL) ≤10°. Fifty-four (64%) achieved a postoperative PI-LL ≤15°, 75 (88%) with a PI-LL ≤20°, and 85 (100%) achieved a PI-LL ≤25°. Correction per SPO was similar regardless of prior fusion (4.87° vs. 5.72° for revisions, p=.192). In a subgroup analysis of SVA greater than 10?cm, there was no significant difference in the final LL, thoracic kyphosis, PI-LL, SVA, CSVL, and TPA, as compared with SVA <10?cm. The LL was the only independent predictor of osteotomy correction per level (LL: β coefficient=?0.108, confidence interval: ?0.141 to 0.071, p<.0001).Conclusions
Multilevel SPOs are feasible for restoration of LL as well as sagittal and coronal alignment in the ASD population with or without prior instrumented fusion. 相似文献25.
Mechanisms of regulation of CXCR4/SDF-1 (CXCL12)-dependent migration and homing in multiple myeloma 总被引:7,自引:0,他引:7
Alsayed Y Ngo H Runnels J Leleu X Singha UK Pitsillides CM Spencer JA Kimlinger T Ghobrial JM Jia X Lu G Timm M Kumar A Côté D Veilleux I Hedin KE Roodman GD Witzig TE Kung AL Hideshima T Anderson KC Lin CP Ghobrial IM 《Blood》2007,109(7):2708-2717
The mechanisms by which multiple myeloma (MM) cells migrate and home to the bone marrow are not well understood. In this study, we sought to determine the effect of the chemokine SDF-1 (CXCL12) and its receptor CXCR4 on the migration and homing of MM cells. We demonstrated that CXCR4 is differentially expressed at high levels in the peripheral blood and is down-regulated in the bone marrow in response to high levels of SDF-1. SDF-1 induced motility, internalization, and cytoskeletal rearrangement in MM cells evidenced by confocal microscopy. The specific CXCR4 inhibitor AMD3100 and the anti-CXCR4 antibody MAB171 inhibited the migration of MM cells in vitro. CXCR4 knockdown experiments demonstrated that SDF-1-dependent migration was regulated by the P13K and ERK/ MAPK pathways but not by p38 MAPK. In addition, we demonstrated that AMD3100 inhibited the homing of MM cells to the bone marrow niches using in vivo flow cytometry, in vivo confocal microscopy, and whole body bioluminescence imaging. This study, therefore, demonstrates that SDF-1/CXCR4 is a critical regulator of MM homing and that it provides the framework for inhibitors of this pathway to be used in future clinical trials to abrogate MM trafficking. 相似文献
26.
Leleu X Xu L Jia X Sacco A Farag M Hunter ZR Moreau AS Ngo HT Hatjiharissi E Ho AW Santos DD Adamia S O'Connor K Ciccarelli B Soumerai J Manning RJ Patterson CJ Roccaro AM Ghobrial IM Treon SP 《Blood》2009,113(3):626-634
Waldenstrom macroglobulinemia (WM) is an incurable low-grade lymphoma characterized by bone marrow (BM) involvement of IgM secreting lymphoplasmacytic cells. The induction of unfolded protein response (UPR) genes ("physiologic" UPR) enables cells to differentiate into professional secretory cells capable of production of high amounts of endoplasmic reticulum (ER)-processed proteins, such as immunoglobulins. Ultimately, the initially cytoprotective UPR triggers an apoptotic cascade if ER stress is not corrected, called proapoptotic/terminal UPR. We show that WM cells inherently express the physiologic UPR machinery compared with normal BM cells, and that increased ER stress leads to proapoptotic/terminal UPR in WM cells. We therefore examined tunicamycin, ER stress inducer, for potential antitumor effects in WM. Tunicamycin induced significant cytotoxicity, apoptosis and cell-cycle arrest, and inhibited DNA synthesis in WM cell lines and primary BM CD19(+) cells from patients with WM with an inhibitory concentration (IC(50)) of 0.5 microg/mL to 1 microg/mL, but not in healthy donor cells. Importantly, coculture of WM cells in the context of the BM microenvironment did not inhibit tunicamycin-induced cytotoxicity. Finally, we demonstrate that ER stress inducer synergizes with other agents used in the treatment of WM. These preclinical studies provide a framework for further evaluation of ER stress inducing agents as therapeutic agents in WM. 相似文献
27.
Ala TA Hughes LF Kyrouac GA Ghobrial MW Elble RJ 《International journal of geriatric psychiatry》2002,17(6):503-509
OBJECTIVE: Since patients with dementia with Lewy bodies (DLB) tend to have greater impairment of attention and construction and better memory ability on neuropsychological tests than patients with Alzheimer's disease (AD), we determined if the items that measure attention, memory, and construction in the Mini-Mental State Examination (MMSE) help to distinguish DLB from AD early in the course of the dementia. DESIGN: We retrospectively studied the first available MMSE exam for each of our patients with DLB or AD and compared their MMSE subscores for attention, memory, and construction. SETTING: A university dementia brain bank in central Illinois, USA. PATIENTS: All patients with neuropathologically-proven DLB or AD with MMSE scores > or =13. RESULTS: We identified 17 DLB and 27 AD patients for whom we had MMSE exams. The attention and construction subtest scores of the DLB group were worse (p=0.0071 and p=0.0038, respectively) than those of the AD group. The memory subscores of the DLB group were better, although the difference did not reach statistical significance (p=0.22). When a mathematical equation was used to combine the three subscores with equal weighting (Attention-5/3Memory+5.Construction), the scores of the DLB group were worse (p=0.00007). Using this equation, a score less than 5 points was associated with DLB with a sensitivity of 0.82 (95% Confidence Interval (CI)=0.57-0.96) and a specificity of 0.81 (95% CI=0.62-0.94). CONCLUSIONS: Our findings support the work of others regarding the relative neuropsychological impairments of DLB and AD and indicate that the MMSE may be helpful in the differentiation of DLB and AD. 相似文献
28.
Pentagon copying is more impaired in dementia with Lewy bodies than in Alzheimer's disease 下载免费PDF全文
Ala TA Hughes LF Kyrouac GA Ghobrial MW Elble RJ 《Journal of neurology, neurosurgery, and psychiatry》2001,70(4):483-488
OBJECTIVES: In many cases the clinical differentiation of patients with dementia with Lewy bodies (DLB) from those with Alzheimer's disease (AD) has been difficult. Because many neuropsychological studies have reported greater visuospatial/constructional impairment in DLB than in AD, it was determined whether accuracy in copying the interlocking pentagons item on the mini mental state examination (MMSE) may be helpful in distinguishing patients with DLB from those with AD relatively early in the course of the dementia. METHODS: All cases of neuropathologically proved DLB and AD in the Center for Alzheimer Disease and Related Disorders brain bank were retrospectively reviewed, and the first available MMSE for each was retrieved. Only patients with MMSE scores > or = 13 were included, indicating mild to moderate dementia. The patients' copies of the interlocking pentagons were analyzed and graded as acceptable or unacceptable according to the original instructions for grading the MMSE. RESULTS: Seventeen patients with DLB and 27 patients with AD were identified for whom MMSE with copies of the interlocking pentagons were available. Two patients with DLB (MMSEs 22 and 27) drew the pentagons acceptably, by contrast with 16 of the patients with AD (MMSEs 13-28). An unacceptable copy was associated with DLB with a sensitivity of 88% and a specificity of 59% (p = 0.002). CONCLUSIONS: For patients with MMSE scores > or = 13, an inability to accurately copy the pentagons suggests that the diagnosis is more likely DLB than AD. The results confirm the work of others on visuospatial/constructional impairment in DLB and indicate that this feature may be helpful in its diagnosis. 相似文献
29.
A DNA endonuclease, isolated from the nuclei of normal human and xeroderma
pigmentosum complementation group A (XPA) cells, which recognizes
predominately pyrimidine dimers, was examined for the mechanism by which it
locates sites of damage on UVC-irradiated DNA. In reaction mixtures with
low ionic strengths (i.e. lacking KCl), the normal and XPA endonuclease
locate sites of UV damage on both naked and reconstituted nucleosomal DNA
by different mechanisms. On both of these substrates, the normal
endonuclease acts by a processive mechanism, meaning that it binds
non-specifically to DNA and scans the DNA for sites of damage, whereas the
XPA endonuclease acts by a distributive one, meaning that it randomly
locates sites of damage on DNA. However, while both the normal and XPA
endonucleases can incise UVC irradiated naked DNA, they differ in ability
to incise damaged nucleosomal DNA. The normal endonuclease showed increased
activity on UVC treated nucleosomal DNA compared with naked DNA, whereas
the XPA endonuclease showed decreased activity on the damaged nucleosomal
substrate. Since a processive mechanism of action is sensitive to the ionic
strength of the micro-environment, the KCl concentration of the reaction
was increased. At 70 mM KCI, the normal endonuclease switched to a
distributive mechanism of action and its ability to incise damaged
nucleosomal DNA also decreased. These studies show that there is a
correlation between the ability of these endonucleases to act by a
processive mechanism and their ability to incise damaged nucleosomal DNA;
the normal endonuclease, which acts processively, can incise damaged
nucleosomal DNA, whereas the XPA endonuclease, which acts distributively,
is defective in ability to incise this substrate.
相似文献
30.
Epidemiological evidence indicates that aflatoxin B1 (AFB1) intake is
associated with an increased risk of hepatocellular carcinoma (HCC). The
hepatocarcinogenesis is initiated by covalent binding of AFB1 to cellular
DNA. To determine whether nutritional factors and hormonal status may
influence the binding of AFB1 to hepatic DNA, a cross- sectional study was
performed on a total of 42 male asymptomatic hepatitis B surface antigen
(HBsAg) carriers and 43 male non-carriers in a cohort study on the
multistage development of HCC in Taiwan. The major AFB1-DNA adduct in vivo,
AFB1-N7-guanine, was measured by high- performance liquid chromatography in
urine. Urinary AFB1-N7-guanine was detectable in 40% of the subjects. HBsAg
carriers had a higher detection rate of urinary AFB1-DNA adducts than
non-carriers and the difference was statistically significant after
multivariate adjustment. After taking into account the total AFB1 urinary
metabolite level, chronic HBsAg carrier status, and other potential
confounders, plasma levels of cholesterol, alpha-tocopherol, and alpha- and
beta-carotene were positively associated with the detection rate of the
AFB1-DNA adducts in a dose-dependent manner, whereas plasma lycopene level
was inversely related to the presence of the adducts in urine. The
association of urinary AFB1-DNA adducts with the plasma levels of
cholesterol, alpha-tocopherol, lycopene, and alpha- and beta-carotene was
observed at both low and high exposure levels of AFB1. There was a
synergistic interaction of plasma alpha-tocopherol with alpha- and beta-
carotene on the adduct levels. No association with the adducts was found
for plasma levels of retinol and testosterone. This study demonstrated
different associations of antioxidant vitamins with AFB1- DNA adduct
formation. The data consistent with our previous finding in cultured
woodchuck hepatocytes that alpha-tocopherol and beta-carotene enhanced
AFB1-DNA adduct formation suggest that prospective investigation of the
relationship between plasma micronutrients and risk of AFB1-related HCC is
warranted.
相似文献