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Among many conventional techniques, nuclear techniques have shown to be faster, more reliable, and more effective in detecting explosives. In the present work, neutrons from a 5 Ci Am-Be neutron source being in water tank are captured by elements of soil and landmine (TNT), namely (14)N, H, C, and O. The prompt capture gamma-ray spectrum taken by a NaI (Tl) scintillation detector indicates the characteristic photo peaks of the elements in soil and landmine. In the high-energy region of the gamma-ray spectrum, besides 10.829 MeV of (15)N, single escape (SE) and double escape (DE) peaks are unmistakable photo peaks, which make the detection of concealed explosive possible. The soil has the property of moderating neutrons as well as diffusing the thermal neutron flux. Among many elements in soil, silicon is more abundant and (29)Si emits 10.607 MeV prompt capture gamma-ray, which makes 10.829 MeV detection difficult. The Monte Carlo simulation was used to adjust source-target-detector distances and soil moisture content to yield the best result. Therefore, we applied MCNP4C for configuration very close to reality of a hidden landmine in soil. 相似文献
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Kevin P. Armstrong Brent Kennedy James T. Watson Patricia K. Morley-Forster Irvan Yee Ronald Butler 《Journal canadien d'anesthésie》2002,49(1):72-80
PURPOSE: The use of opioids in labour analgesia has primarily been as an adjuvant to local anesthetics. For early labour, satisfactory analgesia with epidural sufentanil alone is possible. This study evaluates the impact of epinephrine on sedative side effects and analgesia related to the latter technique. METHODS: After Institutional Review Board approval and informed consent this prospective, randomized, double-blind study evaluated 43 nulliparous subjects requesting epidural analgesia. The study site, a tertiary care obstetric unit, accommodates 3500-4500 deliveries annually. Group selection was randomized and blinded by selection of a sealed envelope containing a number which corresponded to a premixed labelled syringe of saline or epinephrine (100 microg/mL). An epidural catheter was placed in a standardized fashion. All subjects received 40 microg of sufentanil and 0.5 mL from the premixed syringe, diluted to 10 mL with NaCl. A blinded observer collected data on maternal sedation, lightheadedness, hemodynamics, oxygenation, and fetal heart rate over a one-hour period following sufentanil injection. RESULTS: The addition of epinephrine significantly (P <0.05) reduced the incidence of sedation and lightheadedness after epidural sufentanil at all data collection points, except two. Analgesic duration was also significantly prolonged by this addition (120 +/- 56 vs 84 +/- 32 min). Maternal satisfaction was high regardless of solution. CONCLUSION: Forty micrograms of epidural sufentanil produces satisfactory analgesia in early labour. The addition of epinephrine improves the side effect profile of this technique while prolonging the duration of analgesia. Epidural sufentanil requires attention to maternal monitoring of oxygenation as maternal desaturation occurred in both groups. 相似文献
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The local circuitry of the mammalian limbic cortices, including the hippocampus, is capable of generating spontaneous rhythmic activities of 0.5-4 Hz when isolated in vitro. These rhythmic activities are mediated by synchronous inhibitory postsynaptic potentials in pyramidal neurons as the result of repeated discharges of inhibitory interneurons. As such, they are thought to represent an intrinsic inhibitory rhythm. It is unknown at present whether such a rhythm occurs in the immature rodent hippocampus and, if so, the postnatal time window in which it develops. We explored these issues using our recently developed whole mouse hippocampal isolate preparation in vitro. We found that spontaneous rhythmic field potentials started to emerge in mouse hippocampal isolates around postnatal day 10, stabilized after postnatal day 15 and persisted into adulthood. In postnatal days 11-14 mouse hippocampi, the properties of these rhythmic potentials were in keeping with a CA3-driven, IPSP-based intrinsic network activity. The lack of spontaneous field rhythm in neonatal (postnatal days 2-7) hippocampi cannot be attributed to the excitatory activities mediated by gamma-aminobutyric acid type A (GABA-A) receptors, as chloride-dependent hyperpolarizing inhibitory postsynaptic potentials were detectable in neonatal pyramidal neurons at voltages near resting potentials and pharmacological antagonisms of GABA-A receptors produced robust epileptiform discharges in neonatal hippocampi. High frequency afferent stimulation or applications of 4-aminopyridine at low micromolar concentrations failed to induce persistent field rhythm in neonatal hippocampi, suggesting that an overall weak glutamatergic drive is not the sole causing factor. We suggest that the inhibitory postsynaptic potential-based spontaneous rhythmic field potentials develop in a discrete time window during the second postnatal week in the mouse hippocampus due to a fine-tuning in the structure and function of CA3 recurrent circuitry and associated GABAergic inhibitory interneurons. 相似文献
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Deniz Eyice Karabacak Semra Demir Osman Ozan Yeğit Ali Can Kadriye Terzioğlu Derya Ünal Müge Olgaç Raif Coşkun Bahauddin Çolakoğlu Suna Büyüköztürk Aslı Gelincik 《Allergy》2021,76(8):2535-2543
Background
Hereditary angioedema (HAE) attacks can be provoked with psychological factors. The aim of this study was to assess the effects of anxiety, depression and stress related to COVID-19 pandemic on disease activity of HAE patients during the quarantine period (QP) and the return to normal period (RTNP).Methods
This study was conducted between March 2020 and September 2020 in four allergy centres. Demographic, clinical features and mental health status were evaluated in QP (from March to the beginning of June) and RTNP (from June to the beginning of September) applied by the government. The 10-point visual analogue scale (VAS10) was used to define the severity of HAE attacks. Depression, Anxiety and Stress Scales-21 (DASS-21) and Fear of COVID-19 (FC-19) scale were performed to assess mental health status.Results
139 HAE patients were included in the study. In QP, median attack numbers and median VAS10 scores were 5 (min-max: 0–45) and 6 (min-max: 0–10), respectively. HAE attack numbers, DASS-21 stress, anxiety, depression and total DASS-21 scores, and FC-19 scores were higher in QP than RTNP (p = 0.001, p < 0.001, p = 0.001, p < 0.001, p < 0.001, p < 0.001, respectively). However, there was no difference in attack severity scores between the two periods (p > 0.05).Conclusions
This study revealed that the restriction measures during COVID-19 outbreak cause an increase in the number of HAE attacks in relation to anxiety, depression, stress and fear of COVID-19 pandemic. Therefore, it is important to provide psychological support to HAE patients during the pandemic.7.
Farzam Sheikhzadeh Hesari Seyedeh Shaghayegh Hosseinzadeh Mohammad Ali Asl Monadi Sardroud 《Andrologia》2021,53(1):e13914
COVID-19 pandemic leads to health challenges globally, and its diverse aspects need to be uncovered. Multi-organ injuries have been reported by describing potential SARS-CoV-2 entrance routes: ACE2 and TMPRSS2. Since these cell surface receptors’ expression has been disclosed within the male reproductive system, its susceptibility to being infected by SARS-CoV-2 has been summarised through this literature review. Expression of ACE2 and TMPRSS2 at RNA or protein level has been reported across various investigations indicates that the male genitalia potentially is vulnerable to SARS-CoV-2 infection. Presence of SARS-CoV-2 within semen samples and following direct viral damage, secondary inflammatory response causing orchitis or testicular discomfort and finally the amount of viral load leading testicular damage and immune response activation are among probable underlying mechanisms. Therefore, genital examination and laboratory tests should be considered to address the male reproductive tract complications and fertility issues. 相似文献
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Nuriye Aslı Melekoğlu Ali Bay Elif H. Aktekin Mehmet Yilmaz Ercan Sivasli 《Indian journal of hematology & blood transfusion》2017,33(2):211-215
Neonates born to mothers with immune thrombocytopenia (ITP) have an increased risk for neonatal thrombocytopenia and hemorrhagic complications. The aim of this study was to determine the maternal and neonatal outcomes of pregnancies with ITP and also to identify risk factors that predicts neonatal thrombocytopenia. We performed a retrospective analysis of 40 pregnancies with ITP and their 40 neonates. Among the 40 neonates, thrombocytopenia (platelet count of less than 150 × 109/L) was detected in 15 neonates (37.5 %) whom 8 of them had severe thrombocytopenia (platelet count of less than 50 × 109/L). Ten of the 15 neonates with thrombocytopenia required treatment to increase the platelet counts. There was statistically significant association between neonatal thrombocytopenia and maternal splenectomy history and maternal duration of thrombocytopenia. There was no statistically significant correlation between maternal platelet count and neonatal platelet count. Clinicians should pay special attention in these neonates because of risk for development of neonatal thrombocytopenia. Maternal and neonatal outcomes in patients with idiopathic thrombocytopenic purpura is generally good. 相似文献
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