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991.
R. F. WEST 《Medical education》1988,22(2):104-112
The purpose of this study was to assess the degree of consistency in student ratings of teacher effectiveness during the first year of medical school. Student ratings of teaching effectiveness represent a commonly used source of information that enters into the academic decision-making process. In medical school, student evaluations often represent a major source of information that is used in promotion and tenure decisions. It is essential that the precision of such ratings be ascertained so that decision-makers will know how much confidence to place in this source of information on teaching effectiveness. In this study, each member of a first-year medical school class was randomly assigned a two-digit identification number at the beginning of the spring semester, 1986. As the semester progressed students were asked to evaluate each full-time teacher in three major courses. Multiple instructors were utilized in each course (n = 10). Each teacher was evaluated immediately after lectures during the first (T1) and second (T2) halves of the course. Students evaluated the teacher a third time (T3) as part of the end-of-semester overall course evaluation. The teachers were evaluated on a short eight-item Likert-type scale that identified several key indicators of effective teaching. Students attached their anonymous identification numbers to individual ratings so that their responses could be matched in the analysis. The results indicate that medical students are only moderately consistent in the extent to which they evaluate teachers. This inconsistency varied by course and by instructors within courses.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
992.
993.
F J Steinkogler 《Klinische Monatsbl?tter für Augenheilkunde》1988,192(1):20-22
At the end of the 19th century several surgical procedures for the treatment of upper eyelid entropion were described. At that time this type of entropion was much more common than it is today. The goal of treatment is to evert the lashes away from the lid margin. This can be accomplished by tightening the anterior lamella combined with a tarsal wedge resection, or by an upward transposition of the lid skin after splitting the upper lid apparatus. The resulting free anterior tarsal surface must be covered by a free graft to prevent tarsal shrinking. The latter would soon cause a recurrence. After upward transposition of the anterior lamella, the excised skin is very suitable for covering the free tarsal surface. A fibrin sealing method is used to fix the graft on the tarsus, thus making sutures unnecessary. Good results, primarily with regard to function, can be achieved with these methods. 相似文献
994.
Resistance of Helicobacter pylori to antibiotics 总被引:8,自引:1,他引:7
F. MÉGRAUD 《Alimentary pharmacology & therapeutics》1997,11(S1):43-53
Resistance of Helicobacter pylori to antibiotics included in current regimens used to eradicate H. pylori is a major reason for failure. The definition of resistance is not simple, and the clinical relevance of in vitro results must be considered. The different methods of testing antibiotics cannot apply in all cases.
Resistance to clarithromycin has a low prevalence rate (<10%) and its mechanism is well defined (point mutation on the 23S rRNA genes, and decreased binding of the antibiotics to the ribosome). Its clinical relevance is not questioned and, because of a clear occurrence of a bimodal strain population, the method for detecting resistance is not crucial.
Resistance to nitroimidazoles is much more common, probably in the range of 30% or more in Europe. Neither the mechanism of action of metronidazole resistance nor its mechanism of is well known. The redox potential inside the cell which is important in reducing metronidazole to its active metabolite is probably a key element, but the exact metabolites involved are not yet known. Metronidazole resistance was found to be clinically relevant when standard triple therapy was used. The relevance is questioned for triple therapies including a proton pump inhibitor, clarithromycin and metronidazole. More clinical data are needed in this field and the use of agar dilutions is recommended to assess the susceptibility of H. pylori to metronidazole.
The mechanism of resistance to quinolones has been described but these compounds are not currently used for H. pylori infection. No resistance has yet been described for amoxycillin but continuous surveillance is needed in order to detect new cases, as was recently the case for tetracycline resistance. 相似文献
Resistance to clarithromycin has a low prevalence rate (<10%) and its mechanism is well defined (point mutation on the 23S rRNA genes, and decreased binding of the antibiotics to the ribosome). Its clinical relevance is not questioned and, because of a clear occurrence of a bimodal strain population, the method for detecting resistance is not crucial.
Resistance to nitroimidazoles is much more common, probably in the range of 30% or more in Europe. Neither the mechanism of action of metronidazole resistance nor its mechanism of is well known. The redox potential inside the cell which is important in reducing metronidazole to its active metabolite is probably a key element, but the exact metabolites involved are not yet known. Metronidazole resistance was found to be clinically relevant when standard triple therapy was used. The relevance is questioned for triple therapies including a proton pump inhibitor, clarithromycin and metronidazole. More clinical data are needed in this field and the use of agar dilutions is recommended to assess the susceptibility of H. pylori to metronidazole.
The mechanism of resistance to quinolones has been described but these compounds are not currently used for H. pylori infection. No resistance has yet been described for amoxycillin but continuous surveillance is needed in order to detect new cases, as was recently the case for tetracycline resistance. 相似文献
995.
Martin F. Ward Angie Titchen Clare Morrell Brendan McCormack Alison Kitson 《Journal of clinical nursing》1998,7(1):29-36
? The paper describes a multiproject practice development programme undertaken over a period of 1 year. ? The background and development of the programme are outlined, whilst attention is paid to the innovatory nature of the work, particularly the use of inductive, deductive and integrated approaches to both change implementation and project supervision. ? The programme was monitored throughout using different data sources and the paper uses evaluative material retrospectively to provide answers to organizational and professional difficulties which arose during the course of the programme. ? The authors conclude that the use of combinations of different models for practice development has potential, but requires careful supervision. ? They also recommend that those involved in practice development are made fully aware of its local or micropolitics, and develop strategies to deal with change before it occurs, not after it has taken place. 相似文献
996.
997.
E Y S?zmen Z Kerry F Uysal G Yetik M Yasa L Ustünes T Onat 《Clinical chemistry and laboratory medicine》2000,38(1):21-25
There is a large body of literature describing the causative role of oxidative stress mediated by increased levels of reactive oxygen species in the pathogenesis of cardiovascular disease such as atherosclerosis, hypertension, and restenosis after angioplasty. The positioning of a soft silicone collar around the rabbit carotid artery elicits intimal thickening. The findings from recent studies demonstrated that both intimal thickening and atherosclerosis lead to synthesis of inducible nitric oxide synthase, resulting in abundant amounts of nitric oxide. We investigated the effects of collaring and nicardipine treatment on the activities of antioxidant enzymes, superoxide dismutase and catalase, and total nitrite/nitrate levels, stable products of nitric oxide. Placing the collar increased the total nitrite/ nitrate levels and decreased superoxide dismutase activity in collared arteries. Treatment with nicardipine (20 mg/kg/day, s.c.) prevented enhanced nitric oxide degradation without affecting superoxide dismutase and catalase activities. Our results suggest that enhanced nitric oxide production and superoxide anion are generated in response to the collaring, resulting in oxidative stress within the segment in this model. 相似文献
998.
999.
Hereditary haemochromatosis (HH) monocytes have a decreased antibody mediated phagocytosis of rabbit erythrocytes and Staphylococcus aureus compared to control monocytes. In order to investigate whether this decrease could be attributed to a different level of expression of Fcγ receptors (FcγR) or complement receptors (CR), which cooperate even in the absence of complement, the surface expression of these receptors was determined on monocyte-enriched suspensions. In contrast to what was expected, HH monocytes displayed a significantly higher level of FcγRI and FcγRIIa as compared to healthy donor monocytes, but these differences were very small. The expression of the other receptors studied were similar for both groups. The heat-inactivated mouse serum used for opsonizing the erythrocytes mainly contained mouse IgG1. Two genetically different forms of FcγRIIa are known, each with a different affinity for mouse IgG1 antibodies. Therefore, the FcγRIIa polymorphism in monocytes (MN) of both groups was also investigated. A similar distribution was found for patients and healthy donors. In addition, the extent of erythrophagocytosis of both donors and patients was independent of FcγRIIa allotype. Our results indicate that the altered phagocytosis by HH monocytes cannot be attributed to a different level of expression of receptors involved in phagocytosis or to FcγRIIa polymorphism. 相似文献
1000.
The neuropeptide neurotensin (NT) has been shown to modulate mesolimbic dopaminergic activity. Neurotensin injected into the VTA produces motor stimulation and release of dopamine in the nucleus accumbens. In contrast, when neurotensin is administered into the nucleus accumbens, it produces neuroleptic-like effects such as attenuation of the locomotor activity elicited by psychostimulants. In the present study, the hypothesis that neurotensin injected into the nucleus accumbens might modulate the psychostimulant and reinforcing actions of cocaine was tested. In experiment one, rats were trained to self-administer cocaine intravenously on an FR5 schedule of reinforcement. Following the establishment of baseline responding, rats were implanted with bilateral cannulae in the nucleus accumbens. One week later, rats were injected into the nucleus accumbens with various doses of neurotensin (4.2, 8.4 and 16.7 μg, total doses bilaterally) immediately prior to the self-administration session. No significant effects were found with any of the doses of neurotensin tested on the self-administration of cocaine. However, in experiment 2, neurotensin at doses of 4.2 and 16.7 μg injected into the nucleus accumbens significantly reduced the locomotor activation induced by an acute injection of cocaine (15 mg/kg i.p.) and a dose of 16.7 μg attenuated the locomotor activation induced by amphetamine (0.75 mg/kg i.p.). Thus, neurotensin in the nucleus accumbens appears to specifically modulate the acute locomotor activating properties of cocaine but not cocaine self-administration. Different mechanisms by which NT interacts with dopamine in the nucleus accumbens may provide a means of selectively altering psychostimulant motor actions without affecting psychostimulant reinforcement. 相似文献