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1.
Manual assessment of estrogen receptors′ (ER) status from breast tissue microscopy images is a subjective, time consuming and error prone process. Automatic image analysis methods offer the possibility to obtain consistent, objective and rapid diagnoses of histopathology specimens. In breast cancer biopsies immunohistochemically (IHC) stained for ER, cancer cell nuclei present a large variety in their characteristics that bring various difficulties for traditional image analysis methods. In this paper, we propose a new automatic method to perform both segmentation and classification of breast cell nuclei in order to give quantitative assessment and uniform indicators of IHC staining that will help pathologists in their diagnostic. Firstly, a color geometric active contour model incorporating a spatial fuzzy clustering algorithm is proposed to detect the contours of all cell nuclei in the image. Secondly, overlapping and touching nuclei are separated using an improved watershed algorithm based on a concave vertex graph. Finally, to identify positive and negative stained nuclei, all the segmented nuclei are classified into five categories according to their staining intensity and morphological features using a trained multilayer neural network combined with Fisher's linear discriminant preprocessing. The proposed method is tested on a large dataset containing several breast tissue images with different levels of malignancy. The experimental results show high agreement between the results of the method and ground-truth from the pathologist panel. Furthermore, a comparative study versus existing techniques is presented in order to demonstrate the efficiency and the superiority of the proposed method.  相似文献   
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The advent of antibiotics revolutionized medical care resulting in significantly reduced mortality and morbidity caused by infectious diseases. However, excessive use of antibiotics has led to the development of antibiotic resistance and indeed, the incidence of multidrug-resistant pathogens is considered as a major disadvantage in medication strategy, which has led the scholar's attention towards innovative antibiotic sources in recent years. Medicinal plants contain a variety of secondary metabolites with a wide range of therapeutic potential against the resistant microbes. Therefore, the aim of this review is to explore the antibacterial potential of traditional herbal medicine against bacterial infections. More than 200 published research articles reporting the therapeutic potential of medicinal plants against drug-resistant microbial infections were searched using different databases such as Google Scholar, Science Direct, PubMed and the Directory of Open Access Journals (DOAJ), etc., with various keywords like medicinal plants having antibacterial activities, antimicrobial potentials, phytotherapy of bacterial infection, etc. Articles were selected related to the efficacious herbs easily available to local populations addressing common pathogens. Various plants such as Artocarpus communis, Rheum emodi, Gentiana lutea L., Cassia fistula L., Rosemarinus officinalis, Argemone maxicana L, Hydrastis canadensis, Citrus aurantifolia, Cymbopogon citrates, Carica papaya, Euphorbia hirta, etc, were found to have significant antibacterial activities. Although herbal preparations have promising potential in the treatment of multidrug-resistant bacterial infection, still more research is required to isolate phytoconstituents, their mechanism of action as well as to find their impacts on the human body.  相似文献   
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Lasers in Medical Science - Hemorrhoidal disease is a common reason for consultation in proctology. It can be treated in several ways (medical, endoscopic, and surgical). Laser treatment has been...  相似文献   
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Cannabinoid receptors and their ligands play significant roles in regulating bone metabolism. Previous studies of type 1 cannabinoid receptor-deficient mice have shown that genetic background influences the skeletal phenotype. Here, we investigated the effects of genetic background on the skeletal phenotype of mice with type 2 cannabinoid receptor deficiency (Cnr2 ?/?). We studied Cnr2 ?/? mice on a CD1 background and compared the findings with those previously reported in Cnr2 ?/? C57BL/6 mice. Young female Cnr2 ?/? CD1 mice had low bone turnover and high trabecular bone mass compared with wild-type (WT), contrasting with the situation in Cnr2 ?/? C57BL/6 mice where trabecular bone mass has been reported to be similar to WT. The Cnr2 ?/? CD1 mice lost more trabecular bone at the tibia with age than WT due to reduced bone formation, and at 12 months there was no difference in trabecular bone volume between genotypes. This differs from the phenotype previously reported in C57BL/6 Cnr2 ?/? mice, where bone turnover is increased and bone mass reduced with age. There were no substantial differences in skeletal phenotype between Cnr2 ?/? and WT in male mice. Cortical bone phenotype was similar in Cnr2 ?/? and WT mice of both genders. Deficiency of Cnr2 has site- and gender-specific effects on the skeleton, mainly affecting trabecular bone, which are influenced by genetic differences between mouse strains. Further evaluation of the pathways responsible might yield new insights into the mechanisms by which cannabinoid receptors regulate bone metabolism.  相似文献   
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Oxygen evolution reaction (OER) has arisen as an outstanding technology for energy generation, conversion, and storage. Herein, we investigated the synthesis of nickel-based hybrid metal oxides (NixM1−xOy) and their catalytic performance towards OER. NixM1−xOy catalysts were synthesized by solution combustion synthesis (SCS) using the metal nitrates as oxidizer and glycine as fuel. Scanning electron microscope (SEM) micrographs display a porous morphology for the hybrid binary NixM1−xOy, the common feature of combusted materials. X-ray diffraction (XRD) of NixM1−xOy depicted well-defined diffraction peaks, which confirms the crystalline nature of synthesized catalysts. The particle size of as-synthesized materials ranges between 20 and 30 nm with a mesoporous nature as revealed by N2-physisorption. The electrocatalytic performance of the as-prepared materials was evaluated towards OER in alkaline medium. Among them, NixCo1−xOy showed the best catalytic performance. For instance, it exhibited the lowest overpotential at a current density of 10 mA cm−2 (404 mV), onset potential (1.605 V), and Tafel slope (52.7 mV dec−1). The enhanced electrocatalytic performance of NixCo1−xOy was attributed to the synergism between cobalt and nickel and the alteration of the electronic structure of nickel. Also, NixCo1−xOy afforded the highest Ni3+/Ni2+ when compared to other electrocatalysts. This leads to higher oxidation states of Ni species, which promote and improve the electrocatalytic activity.

Ni-based mixed transition metal oxides (MTMO) (NixM1−xOy) were synthesized using the solution combustion synthesis (SCS), and investigated as electrocatalysts towards oxygen evolution reaction (OER) in alkaline medium.  相似文献   
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The endocannabinoid system is recognized to play an important role in regulating a variety of physiological processes, including appetite control and energy balance, pain perception, and immune responses. The endocannabinoid system has also recently been implicated in the regulation of bone metabolism. Endogenously produced cannabinoids are hydrophobic molecules derived from hydrolysis of membrane phospholipids. These substances, along with plant-derived and synthetic cannabinoids, interact with the type 1 (CB1) and 2 (CB2) cannabinoid receptors and the GPR55 receptor to regulate cellular function through a variety of signaling pathways. Endocannabinoids are produced in bone, but the mechanisms that regulate their production are unclear. Skeletal phenotyping of mice with targeted inactivation of cannabinoid receptors and pharmacological studies have shown that cannabinoids play a key role in the regulation of bone metabolism. Mice with CB1 deficiency have high peak bone mass as a result of an osteoclast defect but develop age-related osteoporosis as a result of impaired bone formation and accumulation of bone marrow fat. Mice with CB2 deficiency have relatively normal peak bone mass but develop age-related osteoporosis as a result of increased bone turnover with uncoupling of bone resorption from bone formation. Mice with GPR55 deficiency have increased bone mass as a result of a defect in the resorptive activity of osteoclasts, but bone formation is unaffected. Cannabinoids are also produced within synovial tissues, and preclinical studies have shown that cannabinoid receptor ligands are effective in the treatment of inflammatory arthritis. These data indicate that cannabinoid receptors and the enzymes responsible for ligand synthesis and breakdown play important roles in bone remodeling and in the pathogenesis of joint disease.  相似文献   
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The purpose of this study was to assess the influence of multiple-dose oral administration of azimilide dihydrochloride on CYP2C19-mediated metabolism. A two-period, randomized crossover study was conducted in 40 healthy male subjects who were phenotyped as extensive CYP2C19 metabolizers. Oral doses of placebo or 125 mg of azimilide dihydrochloride were administered every 12 hours for 3 days, followed by every 24 hours for 5 days; 20 mg omeprazole was coadministered on Day 8. Blood or plasma samples were obtained over 24 hours and analyzed for azimilide or omeprazole/5-hydroxyomeprazole using high-performance liquid chromatography with tandem mass spectrometry. Data were analyzed using "noncompartmental" analysis. Azimilide blood concentrations observed in this study were similar to those previously observed at steady state in patients. Based on AUC(m)/AUC(p) for omeprazole, azimilide does not significantly inhibit CYP2C19-mediated metabolism (90% confidence interval [CI] = 104%-111%). For 5-hydroxyomeprazole, no significant changes in pharmacokinetics were observed. For omeprazole, a statistically significant decrease ( approximately 12%) was observed for AUC. However, this change was small and is not expected to be clinically important since the CI was contained within those used to establish bioequivalence. These results indicate that azimilide does not inhibit CYP2C19-mediated metabolism. Since this isozyme had the lowest in vitro IC(50) values for the cytochrome P450s most commonly involved with the metabolism of drugs (CYP1A2, CYP2C9, CYP2C19, CYP2D6, and CYP3A4), azimilide-related drug interactions mediated via these isozymes are not anticipated.  相似文献   
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