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71.
Fourteen children who had had Haemophilus influenzae meningitis more than two years earlier have been compared with their siblings. WISC, Frostig and Bender psychological tests and neurological examination were performed so that subject/sibling differences could be analysed. On neurological examination, subjects overall performed worse than the controls, although no "hard" neurological signs were found. Prolonged fever during the meningitis was associated with poorer results in psychological tests. In the subjects, there was a significant increase in left lateral dominance which may have been due to brain damage by the meningitis. However, most subjects did not differ significantly from their siblings in the tests, suggesting that prompt and adequate treatment of bacterial meningitis can prevent sequelae.  相似文献   
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The basal ganglia occupy a commanding place in neuroscience research, in clinical neurology and in biomedical education. The paucity of our understanding of the role of the basal ganglia in normal everyday life combined with our more extensive knowledge of their deficiencies in a variety of clinical syndromes is a potent spur to continuing investigation. That some of these neurodegenerative syndromes—such as Parkinson's disease—are already common only heightens the need for insight in the face of a population with increasing expectations of longevity. About a decade ago an explosion of information on the connectivity and immunocytochemistry of forebrain structures gave rise to concepts which have shaped the fabric of basal ganglia theory—‘patch and matrix’, ‘disinhibition’, ‘parallel circuits’. Some of these ideas seemed to facilitate an understanding of the basal ganglia, others to render them more complex and impenetrable. Perhaps unsurprisingly, the work of the last decade has tended towards consolidation and refinement. However, several new developments are receiving attention, many of them related to disorders of the basal ganglia. The realisation that some forms of Parkinson's disease have a genetic determinant is gaining strength. The molecular biology of the dopaminergic synapse on the one hand and of the production of insoluble proteins on the other will clearly influence future research into therapeutic options and neuroprotection. The importance of apoptosis, neural plasticity and free radical formation remains unresolved but these are potential areas of promise. Meanwhile, scanning techniques for brain imaging are allowing real time investigation of the working striatum in normal and disordered humans and animals. We believe that the time is opportune for a broad review of current thinking on the basal ganglia in health and disease. The following articles are based on presentations given at a Symposium on the Neurobiology of the Basal Ganglia held at Glasgow University in July 1999 as part of the Summer Meeting of the Anatomical Society of Great Britain and Ireland. The invited speakers were chosen to be wide ranging and contributions encompassed evolution, circuitry and receptors of the basal ganglia, striatal remodelling after dopamine loss, striatal functioning in humans with Huntington's disease and in primate models after midbrain fetal transplants, and the genetics of basal ganglia disorders. Short presentations and posters of current results supplemented the main presentations and some are also included amongst these reviews.  相似文献   
74.
This study compared the ventricular effective refractory periods measured by scanning diastole with an extrastimulus in incremental and decrementaJ steps of 5 msec. The subjects of the study were 80 patients undergoing a clinically indicated electrophysiological test. Eight beat basic drive trains at a cycle length of 600 msec and an intertrain pause of 4 seconds were used to measure the ventricular effective refractory period (VERP). In the incremetal method, the extrastimulus initially was positioned at a coupling interval shorter than the VERP and the coupling interval then was progressively increased until ventricular capture occurred. In the decremental method, the initial extrastimulus coupling interval was longer than the VERP and the coupling interval was progressively shortened until ventricular capture was lost. In 50 subjects, the mean VERP determined by the incremental method, 252 ± 18 (± standard deviation), was significantly longer than the mean VERP determined in the same patients by the decremental method, 248 ± 18 msec (P < 0.0001). In ten subjects, a subthreshold stimulus (S') positioned 10 msec earlier than the VERP had an inhibitory effect that lengthened the VERP by an average of 7 msec; however, when S' was positioned after the seventh beat of an eight heat drive train, no inhibitory effect could be demonstrated. In 20 subjects, VERP's were determined by the incremental and decremental methods using intertrain pauses of 1, 4, 8, 12, and 20 seconds. The mean VERP measured by the incremental method was significantly less than the mean VERP measured by the decremental method when the intertrain pause was 1,4, or 8 seconds, but not when the pause was 12 or 20 seconds. The results of this study demonstrate that incremental scanning of an extrastimulus with eight beat basic drive trains yields a longer VERP than when the extrastimulus is scanned in decremental fashion. The discrepancy between the two methods is not attributable to inhibition by noncapturing extrastimuli in the incremental method, but rather to a decrease in the VERP caused by an effect of extrastimuli that capture the ventricle in the decremental method. Therefore, when a conventional eight beat driye train and 4 second intertrain pause are used to measure ventricular refractoriness, incremental scanning of an extrastimulus yields a more accurate VERP than does decremental scanning.  相似文献   
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A survey of family practice residency programme directors inthe United States was undertaken to look at the impact of malpracticeand malpractice insurance on residency education. Of 385 programmes276 (71.7%) responded to the 20 question survey. The resultsindicated a mean rate of 0.043 claims per resident or facultymember in the previous year. One-fifth of the respondents didnot report the type of malpractice insurance retained for residentsand over half did not report the cost of insurance for residents.Current problems with liability were most often related to theregion of the country, number of visits to the family practicecentre, the number of residents, the number of faculty, thetype of faculty employer and the type of resident employer.Programmes which anticipated future problems with liabilitywere most likely to be those with current problems. The areasidentified as most concerning to residents included: obstetrics,cost of malpractice insurance, difficulty obtaining coverage,and the general anxiety created by malpractice litigation.  相似文献   
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Total cigarettes (all brands) sold weekly by a panel of 60 New Zealand supermarkets were monitored electronically for 42 weeks, a period when cigarette advertisements were in plain format with strong, varied disease warnings. Real cigarette price, newspaper advertising of old, regular and upmarket brands, and the number of newspaper news items on smoking issues were inversely associated with cigarette sales. Tending to increase total sales (all brands) were: more non-shopping days in the current week, and in the week following; volume of grocery items purchased, to indicate income and store traffic; and real advertising expenditure in newspapers for new downmarket cigarette brands, particularly one heavily-advertised brand (Peter Jackson) which was in late 1989 smoked by 4% of teenage smokers. All factors when interacting, explained 93% of changes in weekly cigarette sales. Most of the change occurred in the same week, and was 90% in place after a further 3 weeks. Newspapers, by doubling news coverage of smoking issues or by banning cigarette advertisements, can lower cigarette consumption as much as can a 10% price increase.  相似文献   
80.
Sulfanilamide, sulfathiazole, and sulfadiazine have been fed at 1 per cent levelsin highly purified diets and their effect on growth, mortality, and blood dyscrasiascompared with that of sulfasuxidine.

The soluble drugs produce conditions which are similar to those produced bysulfasuxidine. The growth depression is alleviated in large measure in the case ofsulfanilamide and to a lesser extent for sulfathiazole and sulfadiazine by folic acid.liver extract powder, and dried yeast extract as well as by para-aminobenzoic acid,

The blood dyscrasias due to sulfanilamide, sulfathiazole, and sulfadiazine aresevere leukopenia, granulocytopenia, and mild-to-severe anemia. These are uniformly prevented or the severity greatly curtailed by feeding folic acid, liver extract powder, or dried yeast extract. PABA has a lesser effect in the amounts fed.

Liver extract powder seems to have a beneficial effect on growth and mortalitywhich is not shown by the other supplements. Both free and conjugated folic acid(as yeast extract and in liver extract powder 1:20) are active in combating thedyscrasias.

Evidence from in vitro experiments with Str. haemolyticus (B Lancefield) indicates that neither folic acid, liver extract powder, nor dried yeast extract in ratiosto sulfonamide which are effective in preventing the blood dyscrasias will inhibitor block the bacteriostatic action of the sulfonamide drugs in vitro.

It is suggested that the action of folic acid, liver powder, and yeast extract is notwholly explained by alleviating a folic acid deficiency caused by intestinal bacteriostasis due to the drugs, but by an increased demand of the animals for folicacid in the presence of certain sulfonamides.

Note: We are indebted to Harold Buskirk, Alice Bergdahl, Hallie Ferguson, E. M. Stapert, F. La Plante,and Evon Saggio for valuable assistance in carrying out the experimental work reported here.

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