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71.
The fabricated NaY(WO4)2 was identified through diverse analysis methods. Therefore, to optimize NaY(WO4)2 morphology, saccharide carbohydrates were manipulated as a capping agent. In this study, glucose, fructose, lactose, cellulose, and starch were utilized as the capping agents. SEM images show that fructose was the optimal capping agent for achieving uniform and well-shaped nanoparticles. The photodegradation of organic dyes such as M.O and Rd.B by NaY(WO4)2 was evaluated under UV and Vis light. The bandgap energy of the as-prepared sample was measured by the Tauc plot, and was found to be nearly 3.85 eV. To study the photocatalytic characteristics, the influence of dye dosage and reusability on photodegradation behavior were investigated.NaY(WO4)2 nanoparticles were fabricated via a simple hydrothermal method using saccharide carbohydrates as capping agents. The photocatalytic behavior of the as-prepared NaY(WO4)2 nanostructures was studied. 相似文献
72.
Abolfazl Mohammadbeigi Shahram Arsang-Jang Ehsan Sharifipour Alireza Koohpaei Mostafa Vahedian Narges Mohammadsalehi Masoud Jafaresmaeili Moharam Karami Siamak Mohebi 《急性病杂志》2021,10(4):150-154,后插1
Objective: To identify the incidence rate, relative risk, hotspot regions and incidence trend of COVID-19 in Qom province, northwest part of Iran in the first s... 相似文献
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Mohammad Heydarian Masoud Behzadifar Christos V Chalitsios Mohammad Keshvari Roodabeh Omidifar Mahboubeh Khaton Ghanbari Hasan Abolghasem Gorji Jude Dzevela Kong Jianhong Wu Nicola Luigi Bragazzi 《Ethiopian journal of health sciences》2021,31(6):1109
BackgroundIn February 2020, the Ministry of Health and Medical Education in Iran announced the first case of COVID-19. The aim of this study was to investigate the impact of COVID-19 on the number of CT-Scans and MRI services in public hospitals in western Iran.MethodsWe collected CT-scans and MRI services data from 18 public hospitals via Vice-Chancellor Office, Lorestan University of Medical Sciences from January 2017 to February 2021. Interrupted time series analysis (ITSA) was conducted to assess the impact of COVID-19 on CT-Scans and MRI services. More specifically, ITSA was conducted using ordinary least squares regression with the number of CT-Scans and MRI services per 1,000 registered persons per month as dependent variable.ResultsAt the beginning of the observation period, the monthly rate of CT-Scans was constant (p for trend = 0.267) at 291.9 (from 95%CI 240.5 to 343.4) per 1,000 registered patients. The first case of COVID-19 coincided with an abrupt increase by 211.8 (from 95%CI 102.9 to 320.7) per 1,000 patients. Thereafter, the trend of CT-Scans did not change (p=0.576) compared to the pre-pandemic period. The rate of MRI services was 363.5 per 1,000 per registered patients per month (P = <0.0001) with a slightly decreasing trend (coefficient=-5; 95%CI, -6.9 to -3.1).ConclusionThe findings of this study showed that crises such as COVID-19 can affect the service delivery process. Health policymakers and decision makers should work to prevent potential reductions in health care during events such as COVID-19. 相似文献
75.
Mohammad Hassanpour Seyed Ali Hosseini Tafreshi Omid Amiri Masood Hamadanian Masoud Salavati-Niasari 《RSC advances》2021,11(44):27283
The presence of nanoparticles in the environment and their impact on existing organisms is one of the main concerns of researchers working in this field. In this research, Nd2WO6 nanoparticles were prepared by an ultrasonic procedure for the first time. X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), and energy-dispersive X-ray spectroscopy (EDS) analyses were applied to identify and prove the purity of these particles. In addition to increasing the reaction rate and efficiency with the help of a radical generation mechanism, ultrasound was able to aid the synthesis of these particles. After confirming nanoparticle formation, the optimal nanoparticles in view of scale and morphology were selected by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Optimal particles at three concentrations (25, 50, and 100 ppm) were mixed into the algae growth medium to investigate the effects of the nanoparticles on Dunaliella salina growth. Biological parameters, including the number of cells, biomass, specific growth rate, pigments, and malondialdehyde (MDA), were measured after ten days. Growth parameters showed an increasing trend in concentrations up to 50 ppm; however, at a concentration of 100 ppm, a significant decrease was observed in contrast to the nanoparticles-free treatment. The MDA content showed a linear relationship with enhanced concentration of the nanoparticles. The examination of biological parameters showed that the algae response to stress was dependent on the concentration of nanoparticles. The results showed that 50 ppm of nanoparticles are suitable for increasing algae and achieving a suitable growth rate for commercial purposes. However, in higher concentrations, algal growth inhibition occurs, which is of great importance from a biotechnological point of view.In this work, Nd2WO6 nanoparticles were synthesized by the ultrasonic method for the first time. Also, for the first time, the impact of these nanoparticles on the environment was investigated. 相似文献
76.
Kostas Hadjidimitrakis Masoud Ghodrati Rossella Breveglieri Marcello G. P. Rosa Patrizia Fattori 《The Journal of comparative neurology》2020,528(17):3108-3122
Goal-directed movements involve a series of neural computations that compare the sensory representations of goal location and effector position, and transform these into motor commands. Neurons in posterior parietal cortex (PPC) control several effectors (e.g., eye, hand, foot) and encode goal location in a variety of spatial coordinate systems, including those anchored to gaze direction, and to the positions of the head, shoulder, or hand. However, there is little evidence on whether reference frames depend also on the effector and/or type of motor response. We addressed this issue in macaque PPC area V6A, where previous reports using a fixate-to-reach in depth task, from different starting arm positions, indicated that most units use mixed body/hand-centered coordinates. Here, we applied singular value decomposition and gradient analyses to characterize the reference frames in V6A while the animals, instead of arm reaching, performed a nonspatial motor response (hand lift). We found that most neurons used mixed body/hand coordinates, instead of “pure” body-, or hand-centered coordinates. During the task progress the effect of hand position on activity became stronger compared to target location. Activity consistent with body-centered coding was present only in a subset of neurons active early in the task. Applying the same analyses to a population of V6A neurons recorded during the fixate-to-reach task yielded similar results. These findings suggest that V6A neurons use consistent reference frames between spatial and nonspatial motor responses, a functional property that may allow the integration of spatial awareness and movement control. 相似文献
77.
Salarinasab Sadegh Salimi Leila Alidadiani Neda Shokrollahi Elhameh Arzhanga Pishva Karbasforush Saedeh Marofi Faroogh Nasirzadeh Mahdieh Rahbarghazi Reza Nourazarian Alireza Nikanfar Masoud 《Journal of molecular neuroscience : MN》2020,70(6):819-834
Journal of Molecular Neuroscience - Alzheimer's disease is associated with biochemical and histopathological changes characterized by molecular abnormalities. Due to the lack of effective... 相似文献
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79.
BACKGROUND: Carcinosarcomas are rare neoplasms of the female genital tract. They tend to be highly aggressive and are generally associated with a poor prognosis. Carcinosarcomas of the uterine cervix are extremely rare, with only approximately 35 cases previously reported in English. CASE: A 68-year-old woman presented with cervical carcinosarcoma. She remained without evidence of recurrent disease for 18 months after surgical resection and pelvic radiation treatment. CONCLUSION: In a review of all cases reported in the literature, it appears that cervical carcinosarcomas tend to present at an earlier stage than carcinosarcomas of the uterine corpus, therefore allowing early diagnosis and treatment. They may therefore be associated with a better overall prognosis than their counterparts in the corpus. Some studies have shown improved survival of patients of carcinosarcoma of the uterine corpus whose treatment included postoperative radiation and chemotherapy. Due to the better prognosis of cervical carcinosarcomas, we suggest studies to evaluate the role of aggressive, multimodal therapy, with the intent of obtaining a cure of cervical carcinosarcomas. 相似文献
80.
Medicinal plants have been widely investigated for their various effects. Dracocephalum kotschyi Boiss (Labiatae) is used in Iranian traditional medicine for the treatment of rheumatoid diseases. The inhibitory effect of D. kotschyi on the lectin-induced cellular immune response has been demonstrated previously. In this study, mitogen-treated lymphocytes were exposed to the extract of D. kotschyi and analysed for the induction of apoptosis using flow cytometry and gel electrophoresis. The data obtained indicated a dose-dependent increase of cells in the sub-G1 phase of cell cycle. Study of internucleosomal DNA fragmentation showed a typical DNA laddering in agarose gels. A bioactivity-guided fractionation assay to find the active components responsible for the inhibitory effect of D. kotschyi on mitogen-induced lymphocyte proliferation led to the isolation of calycopterin from the ethyl acetate extract of D. kotschyi. Its structure was identified by spectroscopic methods including( 1)H-NMR, (13)C-NMR, MS and UV spectra. Calycopterin inhibited lymphocyte proliferation in a dose-dependent manner with an IC(50) value of 1.7 microg/mL. In conclusion, the results of this study suggest that D. kotschyi extract has the capacity to induce apoptosis in the lymphocytes and that isolated calycopterin is responsible for the inhibitory effect of D. kotschyi on lymphocyte proliferation. 相似文献