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121.
Tomas Mrkvan Milada Sirova Tomas Etrych Petr Chytil Jiri Strohalm Dana Plocova Karel Ulbrich Blanka Rihova 《Journal of controlled release》2005,110(1):119-129
A novel class of anti-cancer therapeutics - polymeric conjugates of N-(2-hydroxypropyl)methacrylamide (HPMA) copolymers and doxorubicin with pH-controlled release of the drug - is highly efficient in killing tumor cells in vitro and is potent in eradicating growing tumors in vivo. Moreover, in comparison with low-molecular-weight drugs, the macromolecular therapeutics show decreased acute as well as delayed adverse side-toxicity. More importantly, the polymeric conjugates trigger the onset of specific anti-tumor immune response and this anti-tumor immunity can be transferred with splenocytes to na?ve recipients. In other terms, chemotherapy based on conjugates of HPMA copolymer with doxorubicin possesses immunomodulating properties. This finding might also have wider implications for the management of relapsing tumors in human patients. 相似文献
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Jan Valí?ek Marta Harni?árová Andreas ?chsner Zuzana Hutyrová Milena Ku?nerová Hakan Tozan Vít Michenka Vladimír ?epelák Du?an Mita? Jozef Zajac 《Materials》2015,8(11):7401-7422
The paper solves the problem of the nonexistence of a new method for calculation of dynamics of stress-deformation states of deformation tool-material systems including the construction of stress-strain diagrams. The presented solution focuses on explaining the mechanical behavior of materials after cutting by abrasive waterjet technology (AWJ), especially from the point of view of generated surface topography. AWJ is a flexible tool accurately responding to the mechanical resistance of the material according to the accurately determined shape and roughness of machined surfaces. From the surface topography, it is possible to resolve the transition from ideally elastic to quasi-elastic and plastic stress-strain states. For detecting the surface structure, an optical profilometer was used. Based on the analysis of experimental measurements and the results of analytical studies, a mathematical-physical model was created and an exact method of acquiring the equivalents of mechanical parameters from the topography of surfaces generated by abrasive waterjet cutting and external stress in general was determined. The results of the new approach to the construction of stress-strain diagrams are presented. The calculated values agreed very well with those obtained by a certified laboratory VÚHŽ. 相似文献
124.
Pentostatin,cyclophosphamide and rituximab for previously untreated advanced stage,low‐grade B‐cell lymphomas 下载免费PDF全文
Felipe Samaniego Fredrick Hagemeister Jorge E. Romaguera Michelle A. Fanale Barbara Pro Peter McLaughlin M. Alma Rodriguez Sattva S. Neelapu Luis Fayad Anas Younes Lei Feng Zuzana Berkova Tamer Khashab Lalit Sehgal Francisco Vega‐Vasquez Larry W. Kwak 《British journal of haematology》2015,169(6):814-823
We conducted a prospective phase II trial of pentostatin, cyclophosphamide and rituximab as initial therapy for patients with previously untreated advanced stage low‐grade or indolent B‐cell lymphomas (iNHLs). Of 83 evaluable patients, 91·6% attained an overall response and 86·8% a complete or unconfirmed complete response. The 3‐year progression‐free survival (PFS) and overall survival rates were 73% and 93%, respectively. The 3‐year PFS rate was significantly different for different diagnoses (P = 0·01): 83% [95% confidence interval (CI): 0·72, 0·96] for follicular lymphomas, 73% (95% CI: 0·54, 1·0) for marginal zone lymphomas and 61% (95% CI: 0·46, 0·81) for small lymphocytic lymphomas. The most common adverse events were haematological. Of 509 cycles of chemotherapy administered, grade 3 or 4 neutropenia was reported in 68 cycles (13% of cycles administered) and most frequently occurred during cycles 4–6. This is the first report demonstrating the effectiveness of pentostatin, cyclophosphamide and rituximab in patients with previously untreated iNHLs, including those over 60 years of age. 相似文献
125.
Amanda L. Woerman Jan St?hr Atsushi Aoyagi Ryan Rampersaud Zuzana Krejciova Joel C. Watts Takao Ohyama Smita Patel Kartika Widjaja Abby Oehler David W. Sanders Marc I. Diamond William W. Seeley Lefkos T. Middleton Steve M. Gentleman Daniel A. Mordes Thomas C. Südhof Kurt Giles Stanley B. Prusiner 《Proceedings of the National Academy of Sciences of the United States of America》2015,112(35):E4949-E4958
Increasingly, evidence argues that many neurodegenerative diseases, including progressive supranuclear palsy (PSP), are caused by prions, which are alternatively folded proteins undergoing self-propagation. In earlier studies, PSP prions were detected by infecting human embryonic kidney (HEK) cells expressing a tau fragment [TauRD(LM)] fused to yellow fluorescent protein (YFP). Here, we report on an improved bioassay using selective precipitation of tau prions from human PSP brain homogenates before infection of the HEK cells. Tau prions were measured by counting the number of cells with TauRD(LM)–YFP aggregates using confocal fluorescence microscopy. In parallel studies, we fused α-synuclein to YFP to bioassay α-synuclein prions in the brains of patients who died of multiple system atrophy (MSA). Previously, MSA prion detection required ∼120 d for transmission into transgenic mice, whereas our cultured cell assay needed only 4 d. Variation in MSA prion levels in four different brain regions from three patients provided evidence for three different MSA prion strains. Attempts to demonstrate α-synuclein prions in brain homogenates from Parkinson’s disease patients were unsuccessful, identifying an important biological difference between the two synucleinopathies. Partial purification of tau and α-synuclein prions facilitated measuring the levels of these protein pathogens in human brains. Our studies should facilitate investigations of the pathogenesis of both tau and α-synuclein prion disorders as well as help decipher the basic biology of those prions that attack the CNS.James Parkinson first described a progressive deterioration of the nervous system in 1817 and called it “shaking palsy” (1). Almost one century later, Friederich Heinrich Lewy described the neuropathological hallmark now known as Lewy bodies (LBs) (2). Progress toward discerning the etiology of Parkinson’s disease (PD) was achieved 85 years later when the first of several studies identified mutations in or multiplications of the gene encoding α-synuclein, SNCA, in inherited cases of PD (3–5). These studies were corroborated by immunostaining for α-synuclein in brain sections from PD patients (6) and subsequently from dementia with Lewy bodies (DLB) cases (7, 8), which found that LBs are surrounded by a halo of α-synuclein polymers.Along with point mutations in SNCA (3), and duplication and triplication of the gene (4, 5) as causes of inherited PD, meta-analysis of genome-wide association studies (9) have identified common variations in SNCA as a risk factor for sporadic PD cases. Combined, these data strongly support an etiological role for α-synuclein in the pathogenesis of both the inherited and sporadic forms of PD.In 1998, brain sections from cases classified as multiple system atrophy (MSA) were analyzed for α-synuclein. Although no LBs were found, abundant immunostaining in the cytoplasm of glial cells was identified (8, 10, 11). A decade earlier, these large immunopositive deposits of α-synuclein were called glial cytoplasmic inclusions (GCIs) based on silver staining (12); they are primarily found in oligodendrocytes but have been occasionally observed in astrocytes and neurons. Limited ultrastructural studies performed on GCIs suggest that they are collections of poorly organized bundles of α-synuclein fibrils (8).In addition to the accumulation of α-synuclein into LBs in PD and GCIs in MSA, depigmentation of the substantia nigra pars compacta is a hallmark of both PD and the majority of MSA cases (13). This loss of dopaminergic neurons results in diminished input to the basal ganglia that is reflected in the motor deficits exhibited by patients. In the 1990s, fetal tissue transplants into the substantia nigra of PD patients were performed in an attempt to counteract the effects of dopamine loss. Strikingly, upon autopsy of patients that survived at least 10 years posttransplant, LBs were found in the grafted fetal tissue. Because these grafts were no more than 16 years old, the findings argued for host-to-graft transmission of LBs (14, 15). The results of these transplant studies offered evidence supporting the hypothesis that PD is a prion disease, characterized by a misfolded protein that self-propagates and gives rise to progressive neurodegeneration (16, 17). Additional support for this hypothesis came from studies on the spread of α-synuclein deposits from the substantia nigra to other regions of the CNS in PD patients (18).Even more convincing support for α-synuclein prions came from animal studies demonstrating the transmissibility of an experimental synucleinopathy. The first report used transgenic (Tg) mice expressing human α-synuclein containing the A53T mutation found in familial PD; the mice were designated TgM83 (19). Homozygous mice (TgM83+/+) were found to develop spontaneous motor deficits along with increased amounts of insoluble phosphorylated α-synuclein throughout the brain between 8–16 months of age. Ten years later, Mougenot et al. (20) intracerebrally inoculated brain homogenates from sick TgM83+/+ mice into ∼2-months-old TgM83+/+ mice and found a substantial reduction in the survival time with incubation periods of ∼130 days. Similar observations were reported from two other groups using either homozygous TgM83+/+ (21) or hemizygous TgM83+/− (22) mice.Although our initial attempts to transmit PD to TgM83+/− mice failed (23), the transmission of MSA to the same mouse line was the first demonstration of α-synuclein prions in human brain (22). The TgM83+/− mice, which differ from their homozygous counterparts by not developing spontaneous disease, exhibited progressive CNS dysfunction ∼120 days following intrathalamic inoculation of brain homogenates from two MSA patients. Inoculation of brain fractions enriched for LBs from PD patients into wild-type (WT) mice and macaque monkeys induced aberrant α-synuclein deposits, but neither species developed neurological disease (24). In a similar approach, inoculation of WT mice with the insoluble protein fraction isolated from DLB patients also induced phosphorylated α-synuclein pathology after 15 months, but it failed to induce neurological disease characteristic of DLB (25).Because α-synuclein prions from MSA patients were transmissible to TgM83+/− mice, we asked whether a more rapid cell-based bioassay could be developed to characterize the MSA prions. With the cell bioassay for progressive supranuclear palsy (PSP) in mind (26, 27), we began by constructing WT and mutant α-synuclein cDNAs fused to yellow fluorescent protein (YFP) (28–30) and expressed these in human embryonic kidney (HEK) cells. By testing the cells with full-length recombinant mutant human α-syn140*A53T fibrils, we induced aggregate formation in HEK cells expressing WT and mutant human SNCA transgenes. To expand these findings beyond synthetic prions and to examine natural prions, we report here that phosphotungstic acid (PTA) (31) can be used to selectively precipitate α-synuclein from MSA patients. Screening PTA-precipitated brain homogenate with our cellular bioassay, we detected MSA prions in all six of the cases examined. By measuring the distribution of prions in the substantia nigra, basal ganglia, cerebellum, and temporal gyrus, we found evidence to suggest that at least three different strains of α-synuclein prions may give rise to MSA. We also found that after enrichment by PTA precipitation, ∼6 million α-synuclein molecules comprised an infectious unit of MSA prions in cell culture. Importantly, we transmitted neurodegenerative disease to TgM83+/− mice using PTA-precipitated brain homogenate from an MSA patient, confirming that the aggregate isolation methods used successfully purify prions from patient samples. 相似文献
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127.
Daniele Gibelli Valentina Pucciarelli Zuzana Caplova Annalisa Cappella Claudia Dolci Cristina Cattaneo Chiarella Sforza 《Journal of cranio-maxillo-facial surgery》2018,46(9):1493-1499
The present study compared the reliability of a low-cost laser scanner device to an already-validated stereophotogrammetric instrument. Fifty volunteers underwent duplicate facial scans through laser scanner and stereophotogrammetry. Intra- and inter-instrument reproducibility of linear distances, angles, facial surface area and volume was verified through the Bland–Altman test and calculation of absolute (TEM) and relative (rTEM) technical errors of measurement; rTEM was then classified as follows: <1% excellent; 1–3.9% very good; 4–6.9% good; 7–9.9% moderate; >10% poor. The scans performed through different devices were registered and superimposed to calculate the root mean square (RMS) (point-to-point) distance between the two surfaces. The same protocol was applied to a mannequin head. In inter-instruments comparison, 12/26 measurements showed a “good” rTEM; 5 were “very good”. In intra-instrument comparison, most performances worsened, with only 10 of 26 measurements classified as “good” and “very good”. All the measurements made on mannequin scans were at least “good”, and 14/26 were “very good”. Surface area was “very good” only in intra-instrument comparison; conversely, volumes were poorly repeatable for all the comparisons. On average, RMS point-to-point distances were 0.65 mm (inter-devices comparison), 0.56 mm (mannequin scans), 0.42 mm (intra-device comparison). In conclusion, the low-cost laser scan device can be reliably applied to inanimate objects, but does not meet the standards for three-dimensional facial acquisition on living persons. 相似文献
128.
The unmanaged Norway spruce montane forests in the Bohemian Forest National Park (Czech Republic) suffered from repeated large-scale bark beetle outbreaks in last decade. In this study, the diversity of culturable foliar endophyte microfungi in needles originating from eleven recently wind-fallen trees in this area was surveyed. Our aims were to describe their diversity and to determine the relative host and organ specificities of isolated endophyte species to estimate the species pool and abundance of foliar endophytes before the forest degradation. Microfungi were isolated from surface-sterilized needles, and the outgrowing strains were identified based on morphological and molecular characteristics (analyses of ITS1, ITS2 and partial 28S rDNA). Fungal communities in the needles were diverse, with ascomycetes (mostly anamorphs of Helotiales) dominating basidiomycetes. The most frequent species (Phacidiopycnis sp., Cistella acuum, Sirococcus sp. and two species of Chalara) did not correspond with those recorded in previous studies of Picea spp. For example, the widely distributed Lophodermium piceae was rarely recorded in this study. This pattern may be caused by different methods of sterilization and cultivation or by physiological characteristics of the needles, or it may reflect the species distribution in the studied area. Members of the Helotiales, along with sequences from GenBank, showed substantial overlap in host affinities, most prominently between Pinus and Picea, and also among species from distant plant lineages. 相似文献
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130.