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71.
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A new instable aristolane type sesquiterpene ketone, gansongone ( 1), was isolated from the fresh underground parts of NARDOSTACHYS CHINESIS Batalin (Valerianaceae), growing in the province Sichuan (China). The structure of 1 was elucidated by spectroscopic and chemical methods. The structure of the corresponding alcohol 2, which was also found in N. CHINENSIS and formerly regarded as 9-aristolene-1alpha-ol ( 5) has to be revised to l(10)-aristolene-9beta-ol ( 2) from results of 2D-NMR-spectroscopy and oxidation to 1. Besides 1 and 2, the following compounds have been identified in the ethanol extract of the fresh plant material of N. CHINENSIS: nardosinone, nardosinondiol, deoxonarchinol A, beta-sitosterol, oleanolic acid, ethyl beta- D-glucopyranoside.  相似文献   
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Training in gerontology in American institutes of higher education is conceptualized and realized in response to present societal demands. Although plurality of approaches prevails, gerontology has become an institutionalized discipline which in its research, training and application is formally sponsored by the national government. Programs are offered in many colleges and universities and assessed in terms of scientific excellence, of efficiency in teaching knowledge from multiple disciplines, and in terms of practicality. But still, problems of poor research and "quasi-professional" teaching, as well as of insufficiently founded practical work concern gerontologists. In a time of expansion, "instant gerontologists" have become a threat to the field. A brief "instant gerontologists" have become a threat to the field. A brief overview on questions presently discussed among teachers in gerontology is given, and a model-institution for gerontological training is briefly described, the Andrus Gerontology Center at the University of Southern California.  相似文献   
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The isolation of Chryseobacterium indologenes as a causative micro-organism in human diseases is rare. Risk factors for infections caused by this pathogen include very young and very old age, indwelling devices, immune suppression and recent use of broad-spectrum antibiotics. Most cases suffer from bacteraemia or nosocomial pneumonia, whilst infection of the central nervous system (CNS) is extremely rare. We present a term-born infant diagnosed prenatally with holoprosencephaly and obstructive hydrocephalus, requiring post-natal ventriculoperitoneal shunt insertion. At 6 weeks of age, he suffered from Escherichia coli meningitis, showing satisfactory clinical response with antimicrobial therapy. Aged 11 months, he suffered from hyper-drainage syndrome, resulting in the removal of the shunt system. He represented 11 days post-operatively, with low-grade fever, irritability and cerebrospinal fluid (CSF) leakage. C. indologenes from CSF was isolated and antimicrobial therapy with ceftazidime and trimethoprim–sulfamethoxazole for 3 weeks resulted in good clinical response. This is the first documented community-acquired CNS infection due to C. indologenes in an infant without concomitant indwelling device or previous antibiotic pressure.  相似文献   
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BACKGROUND: This prospective study aimed to determine whether cognitive-behavioural group treatment accompanying medical standard care is effective in reducing psychological distress in patients with inflammatory bowel disease. METHODS: Twenty-eight outpatients with Crohn disease or ulcerative colitis completed the treatment programme. Psychological treatment consisting of 12 weekly sessions was conducted in a group setting. Medical and psychometric assessments were taken at the beginning of the 3-month pretreatment waiting period, at pretreatment, at post-treatment and at the 3, 6 and 9-month follow-ups. RESULTS: During baseline, no change was observed in psychological distress. Disease-related worries and concerns decreased significantly from pretreatment to the follow-ups. The disease groups differed in the decline of concerns between pre- and post-treatment, with a significant reduction of concerns in patients with ulcerative colitis but not Crohn disease. This difference did not occur at the follow-ups, indicating long-term improvement for both disease groups. Depressive coping decreased significantly in women and remained stable at the follow-ups, whereas depressive coping did not change in men. The same gender difference was found for depressive symptoms. CONCLUSIONS: The exploratory findings suggest that psychological group treatment for outpatients is a feasible and effective approach for the short- and long-term reduction of psychological distress for patients with inflammatory bowel disease. However, the revealed gender differences on coping and depression might indicate the necessity to consider gender-specific aspects of inflammatory bowel disease when designing and evaluating psychological interventions.  相似文献   
78.
Glibenclamide is a potent inhibitor of the ATP-dependent potassium channel. Opening of the ATP-dependent potassium channel is regarded as a mechanism of ischemic preconditioning. This in vitro study examines the influence of glibenclamide and glimepiride, a new sulfonylurea, on the negative inotropic action of the potassium channel opener rilmakalim in isolated ventricular myocytes. Cardiac myocytes were isolated from adult guinea pig hearts by collagenase perfusion and incubated with rilmakalim (concentration range 0.1-12.0 microM), glibenclamide (concentration range 0.03-3.0 microM) plus rilmakalim (3.0 or 7.5 microM), and glimepiride (0.03-9.0 microM) plus rilmakalim (3.0 or 7.5 microM) and paced by electrical field stimulation. Contractility of the myocytes was evaluated by digital image analysis, intracellular free calcium was determined by means of fura-2 fluorescence measurements, and cell viability was assessed morphologically as well as by measurement of lactate dehydrogenase activity. Rilmakalim reduced the systolic intracellular free calcium and contractility of ventricular myocytes in a concentration dependent manner. This effect was antagonized by glibenclamide at lower concentrations (0.3 microM) than glimepiride (3.0 microM). The smaller antagonistic action of glimepiride on the negative inotropic effect of rilmakalim as compared with glibenclamide most likely reflects a less potent inhibition of ATP-dependent potassium channels by glimepiride.  相似文献   
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Gly-Arg-Gly-Asp-Ser (GRGDS) was modified by conjugation to lauric acid (LA) to facilitate incorporation into the matrix of a poly(carbonate-urea)urethane (PCU) used in vascular bypass grafts. GRGDS and LA-GRGDS were synthesized using solid phase Fmoc chemistry and characterized by high performance liquid chromatography and Fourier transform infrared spectroscopy. LA-GRGDS was passively coated and incorporated as nanoparticle dispersion on the PCU films. Biocompatibility of the modified surfaces was investigated. Endothelial cells seeded on LA-GRGDS coated and incorporated PCU showed after 48 h and 72 h a significant (p < 0.05) increase in metabolism compared with unmodified PCU. The platelet adhesion and hemolysis studies showed that the modification of PCU had no adverse effect. In conclusion, LA-conjugated RGD derivatives, such as LA-GRGDS, that permit solubility into solvents used in solvent casting methodologies should have wide applicability in polymer development for use in coronary, vascular, and dialysis bypass grafts, and furthermore scaffolds utilized for tissue regeneration and tissue engineering.  相似文献   
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