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101.
Mohammed Shaheen Lena Schindler Rotem Saar-Ashkenazy Kifah Bani Odeh Hermona Soreq Alon Friedman Clemens Kirschbaum 《Psychophysiology》2020,57(1):e13271
Violent conflicts are severe traumatic stressors with detrimental effects on physical and mental health, with children and adolescents being particularly at risk. For the hypothalamic–pituitary–adrenal (HPA) axis, characteristic patterns of dysregulation in trauma-exposed individuals have been shown. This study set out to investigate self-reported mental well-being in Palestinian adolescents growing up during the Israeli–Palestinian conflict. Hair cortisol concentrations (HCC) as a psychoendocrine marker for long-term HPA axis aberrations along with the potential protective factor sense of coherence (SoC; i.e., the global mindset to interpret the world and emerging stressors as comprehensible, manageable, and meaningful) were examined. Between 2014 and 2016, posttraumatic stress disorder (PTSD), depression, anxiety, HCC, and SoC were examined in 233 adolescents aged 11 to 16 from the West Bank. More than half of the participants reported trauma exposure, with 40% fulfilling the criteria of a preliminary PTSD diagnosis and a high prevalence of anxiety and depression. HCC was significantly elevated in the PTSD subgroup compared to the subgroup not exposed to any traumatic events (p = 0.046), with trauma-exposed individuals in between. HCC was further associated with typical sequelae of traumatic stress. Notably, SoC was inversely related to self-reported psychopathology, as well as to HCC in the trauma group. The results illustrate the situation of adolescents exposed to chronic traumatic stress and extend the literature on aberrant HPA axis functioning under such conditions. They also point out a central role of SoC, which may imply new strategies to aid individuals exposed to ongoing conflicts. 相似文献
102.
Kraniomandibuläre Dysfunktionen (CMD) sind in erster Linie gekennzeichnet durch Schmerzen im Bereich von Kaumuskeln und Kiefergelenken und durch Bewegungseinschränkungen des Unterkiefers. Im Juni 2019 stellte die Deutsche Gesellschaft für Funktionsdiagnostik und -therapie einen Screening-Frage- und Befundbogen vor, mit dessen Hilfe Personen mit einer CMD erkannt werden sollen. Der Bogen besteht aus einem Anamnese- (drei schmerz- und eine unterkieferfunktionsbezogenen Frage) und einem Untersuchungsteil (fünf Erhebungen: Palpation von Kaumuskeln und Kiefergelenken; Bestimmung der maximalen Kieferöffnung; Beurteilung des Vorliegens von Okklusionsstörungen; Erfassung von Kiefergelenkgeräuschen). Der vorliegende Beitrag geht zwei Fragen nach: (1) Welche der neun Bestandteile des Bogens sind sinnvoll, welche nicht? (2) Ist grundsätzlich ein CMD-Screening empfehlenswert? Während die anamnestischen Fragen die klinisch relevanten Symptome von CMD-Patienten widerspiegeln und daher ebenso wie die Ermittlung der maximalen Kieferöffnung sinnreiche Maßnahmen sind, trifft dies für die vier anderen klinischen Erhebungen nicht zu. Dessen ungeachtet erscheint ein CMD-Screening für schmerzhafte CMD unnötig, weil ein Patient mit orofazialen Schmerzen und/oder eingeschränkter Unterkiefermobilität bei hohem Leidensdruck von selbst einen Therapeuten aufsuchen wird. Aus diesen Gründen birgt der Einsatz des hier vorgestellten CMD-Frage- und Befundbogens die Gefahr einer Überdiagnostik, verbunden mit der Einleitung nicht indizierter diagnostischer und therapeutischer Maßnahmen. 相似文献
103.
B-cell growth factor receptor expression and B-cell growth factor response of leukemic B cell precursors and B lineage lymphoid progenitor cells 总被引:8,自引:1,他引:8
Uckun FM; Fauci AS; Heerema NA; Song CW; Mehta SR; Gajl-Peczalska K; Chandan M; Ambrus JL 《Blood》1987,70(4):1020-1034
The purpose of this study was to analyze the expression of B cell growth factor (BCGF) receptors and to elucidate the biologic effects of biochemically purified natural BCGF at the B cell precursor stage of human B lineage lymphoid differentiation. The specific binding of radioiodinated high-mol-wt BCGF (125I-HMW-BCGF) and low-molecular-wt BCGF (125I-LMW-BCGF) to fresh marrow blasts from B cell precursor acute lymphoblastic leukemia (ALL) patients was initially investigated. The estimated number of radioiodinated BCGF molecules bound per blast ranged from undetectable to 24.3 X 10(3) for HMW-BCGF, and from 11.5 X 10(3) to 457.8 X 10(3) for LMW-BCGF. In 3H-TdR incorporation assays, 75% of cases showed a significant response to LMW-BCGF with a median stimulation index of 9.3. By comparison, only 33% of cases showed a significant response to HMW-BCGF with a median stimulation index of 2.4. Subsequently, B cell precursor colony assays were performed to assess and compare the biologic effects of BCGF on leukemic B lineage lymphoid progenitor cells. Among 28 cases studied, 57% responded to both HMW-BCGF and LMW-BCGF, 21% responded only to LMW-BCGF, and the remaining cases showed no proliferative response to either growth factor. The response patterns of virtually pure populations of FACS- sorted leukemic B cell precursors were essentially identical to the proliferative responses of unsorted leukemic B-cell precursors. Synergistic effects between HMW-BCGF and LMW-BCGF were observed in 80% of the cases that responded to both. The numbers of cell-bound radioiodinated BCGF molecules, the stimulation indices, as well as the number of B cell precursor colonies in BCGF-stimulated cultures showed a marked interpatient variation. Patients with structural chromosomal abnormalities (SCAs) involving 12p11-13 or patients with a Philadelphia chromosome showed a greater HMW-BCGF response at the level of leukemic progenitor cells than did other patients (P = .02). The LMW-BCGF response was significantly greater for patients with SCA than for patients without SCA (P = .04). The response of leukemic progenitor cells to HMW-BCGF or LMW-BCGF did not correlate with sex, age, disease status, FAB morphology, WBC at diagnosis, or immunophenotype. To our knowledge, this study represents the first detailed analyses of BCGF receptor expression and BCGF effects in B cell precursor ALL. The data presented provide direct evidence for the expression of functional receptors for both HMW-BCGF and LMW-BCGF in B cell precursor ALL. 相似文献
104.
Malena Mielke Lea Marie Reisch Alexandra Mehlmann Sebastian Schindler Christian G. Bien Johanna Kissler 《Human brain mapping》2022,43(2):787
Human vision prioritizes emotional stimuli. This is reflected in stronger electrocortical activation in response to emotional than neutral stimuli, measurable on the surface of the head. Feedback projections from brain structures deep within the medial temporal lobes (mTLs), in particular the amygdala, are thought to give rise to this phenomenon, although causal evidence is rare. Given the many pathways involved in visual processing, the influence of mTL structures could be restricted to specific time windows. Therefore, we delineate the temporal dynamics of the impact of right mTL structures on affective picture processing, investigating event‐related potentials (ERPs) in 19 patients (10 female) with right mTL resections and 19 individually matched healthy participants, while they viewed negative and neutral scenes. Groups differed significantly at early‐ and mid‐latency processing stages. Patients with right mTL resection, unlike controls, showed no (P1: 90–140 ms) or marginal (N1: 170–220 ms) emotion modulation. At mid‐latency (early posterior negativity: 220–370 ms), emotion modulation over the ipsi‐resectional right hemisphere was smaller in patients than in controls, but groups did not differ over the left hemisphere. During late parietal positivities (400–650 ms and 650–900 ms), both groups had similar emotion modulation. Our results demonstrate that right mTL structures attenuate particularly early processing of affectively negative scenes. This is theoretically consistent with an initial amygdala‐dependent feedforward sweep in visual emotion processing whose absence is successively compensated. Findings specify the impact of right mTL structures on emotional picture processing and highlight the value of time‐resolved measures in affective neuroscience.We have compared event‐related potential correlates of affective picture processing in 19 patients with right temporal lobe resections including the amygdala and individually matched healthy controls. Our results show that particularly early processing stages (P1, ipsi‐resectional N1 and early posterior negativity) are impaired by the resections, whereas late positivities are largely intact. These findings constrain theories on the role of medial temporal lobe structures in visual affective stimulus processing. 相似文献
105.
106.
Aven‐mediated checkpoint kinase control regulates proliferation and resistance to chemotherapy in conventional osteosarcoma 下载免费PDF全文
Zuzanna Baranski Tijmen H Booij Anne‐Marie Cleton‐Jansen Leo S Price Bob van de Water Judith VMG Bovée Pancras CW Hogendoorn Erik HJ Danen 《The Journal of pathology》2015,236(3):348-359
Conventional high‐grade osteosarcoma is the most common primary bone sarcoma, with relatively high incidence in young people. In this study we found that expression of Aven correlates inversely with metastasis‐free survival in osteosarcoma patients and is increased in metastases compared to primary tumours. Aven is an adaptor protein that has been implicated in anti‐apoptotic signalling and serves as an oncoprotein in acute lymphoblastic leukaemia. In osteosarcoma cells, silencing Aven triggered G2 cell‐cycle arrest; Chk1 protein levels were attenuated and ATR–Chk1 DNA damage response signalling in response to chemotherapy was abolished in Aven‐depleted osteosarcoma cells, while ATM, Chk2 and p53 activation remained intact. Osteosarcoma is notoriously difficult to treat with standard chemotherapy, and we examined whether pharmacological inhibition of the Aven‐controlled ATR–Chk1 response could sensitize osteosarcoma cells to genotoxic compounds. Indeed, pharmacological inhibitors targeting Chk1/Chk2 or those selective for Chk1 synergized with standard chemotherapy in 2D cultures. Likewise, in 3D extracellular matrix‐embedded cultures, Chk1 inhibition led to effective sensitization to chemotherapy. Together, these findings implicate Aven in ATR–Chk1 signalling and point towards Chk1 inhibition as a strategy to sensitize human osteosarcomas to chemotherapy. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
107.
108.
Christoph Romanin Jan -Olof Karlsson Hansgeorg Schindler 《Pflügers Archiv : European journal of physiology》1992,421(5):516-518
Ca2+ -induced inactivation of L-type Ca2+ channels is proposed as an important negative feedback mechanism regulating Ca2+ entry. Here, for the first time, evidence for modification of heart L-type Ca2+ channel activity by cytoplasmic calcium is provided from excised insideout membrane patches. Ba2+ currents through cardiac L-type Ca2+ channels exhibited only modest inactivation in the absence of cytoplasmic Ca2+. Elevation of cytoplasmic Ca2+ to micromolar concentrations strikingly affected L-type Ca2+ channel activity as evaluated from ensemble average Ba2+ currents. Inactivation was markedly increased concomitant with a reduction of peak inward current, which was almost completely eliminated at about 15 M cytoplasmic Ca2+ concentration. Half maximal suppression of Ba2+ currents was observed at 2.3 M Ca2+. The observed modifications of L-type Ca2+ channel activity show that cytoplasmic Ca2+ induces channel closure. Below 4 M Ca2+, channels can be reversibly reactivated during repetitive depolarizations, while at high Ca2+ concentrations (15 M) most Ca2+ channels reside in a closed state. This may allow for a delicate regulation of Ca2+ entry, and consequently of heart contraction. 相似文献
109.
小鼠皮肤超氧化物歧化酶活性与枸杞多糖的干预 总被引:1,自引:0,他引:1
目的:观察枸杞多糖对皮肤胶原代谢和自由基产生的影响,探讨其抗皮肤衰老的作用。方法:实验于2005-06/2006-05在广东医学院整形外科研究所完成。①实验材料:清洁级昆明小鼠60只,月龄2个月,体质量16~24g,雌雄各半。②实验分组:将小鼠随机分为正常对照组、衰老模型组和抗衰老模型组,每组20只。③实验干预:模型组每日用D-半乳糖溶液皮下注射制造衰老模型,用量和时间为80mg/(kg·d)7d,120mg/(kg·d)14d,140mg/(kg·d)14d,180mg/(kg·d)7d。正常对照组每日注射同体积的生理盐水。抗衰老模型组在注射D-半乳糖期间以枸杞多糖灌胃,剂量为20mg/(kg·d),正常对照组和衰老组则以同体积的生理盐水代之灌胃。④实验评估:42d后切取小鼠颈背部皮肤,测定超氧化物歧化酶活力、羟脯氨酸和丙二醛含量。结果:56只小鼠进入结果分析(4只死亡)。①小鼠皮肤超氧化物歧化酶活力:与正常对照组相比,衰老组和抗衰老组小鼠皮肤超氧化物歧化酶活力降低,差异有显著性意义(P<0.01);抗衰老组与衰老模型组比较,超氧化物歧化酶活力增加,差异有显著性意义(P<0.01)。②与正常对照组相比,衰老组和抗衰老组小鼠皮肤羟脯氨酸和丙二醛含量增加,差异有显著性意义(P<0.01);抗衰老组与衰老组比较,羟脯氨酸和丙二醛含量均降低,差异有显著性意义(P<0.01)。结论:枸杞多糖改善皮肤老化的作用与提高小鼠皮肤超氧化物歧化酶活力,降低羟脯氨酸、丙二醛含量,影响胶原代谢有关。 相似文献
110.
Frédéric Zubler Andreas Steimer Rebekka Kurmann Mojtaba Bandarabadi Jan Novy Heidemarie Gast Mauro Oddo Kaspar Schindler Andrea O. Rossetti 《Clinical neurophysiology》2017,128(4):635-642