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51.
Following the ingestion of an alleged aphrodisiac known as "yo-yo," a 16-year-old girl experienced an acute dissociative reaction accompanied by weakness, paresthesias, and incoordination. Subsequent symptoms included anxiety, headache, nausea, palpitations, and chest pain. Hypertension, tachycardia, tachypnea, diaphoresis, pallor, tremors, and an erythematous rash were noted on physical examination. Serum epinephrine and norepinephrine levels were found to be elevated. Symptoms resolved spontaneously but lasted approximately 36 hours. The ingested substance was identified as yohimbine. The pharmacology of yohimbine and the treatment of yohimbine poisoning are discussed.  相似文献   
52.
Medicine, Health Care and Philosophy - Despite the longstanding debate on definitions of health and disease concepts, and the multitude of accounts that have been developed, no consensus has been...  相似文献   
53.
Needle biopsy of renal allografts: comparison of two techniques   总被引:2,自引:0,他引:2  
Two techniques for renal allograft biopsy were retrospectively evaluated to compare relative safety and efficacy. After ultrasound (US) localization of the kidney and biopsy with a hand-held 14-gauge cutting needle, an adequate specimen was obtained in 74 of 77 cases (96%). Major complications occurred in six of these 77 cases (8%). One hundred four biopsies were performed by using a smaller 18-gauge cutting needle with a spring-loaded biopsy "gun" and real-time US guidance. With this newer technique, specimens adequate for diagnosis were obtained in 99 biopsies (95%). There was a single major complication with this technique (1%). The 18-gauge needle with real-time US guidance yields comparably adequate specimens with a lower frequency of complications.  相似文献   
54.
The dental curriculum at the University of Nijmegen is based on what the dentist should know and be able to do after his graduation. The programme is divided up into cognitive, behavioural and motoric modules. These modules are vertically connected through subsequent course years by thematically related lines. For every module, the general objectives and general contents have been formulated. Moreover, all subcomponents have been specified as instructional objectives. Half of the study hours is reserved for practical dentistry, by means of preclinically laboratory courses or patient treatment. The curriculum is based on a scientific approach of dentistry and emphasis is placed on patient related instructional situations.  相似文献   
55.
In the orthodontic treatment of young patients with missing maxillary incisors one should make an effort to avoid prosthetic solutions. This not only applies to situations with agenesis of maxillary lateral permanent incisors, but also to those cases in which maxillary incisors cannot be maintained after trauma. Standard solutions are presented for various sagittal jaw relationships and types and number of teeth missing. Specific rules have to be observed for the closure of spaces due to missing teeth in order to reduce the occurrence of papillae retraction and to place the substituting teeth in such a position that their crowns can be built up to look like the originals. This requires mesiodistal angulations that deviate from the standard ones, a proper distribution of crown width and in most cases a permanent retention with a palatally bonded thin multistranded wire.  相似文献   
56.
BACKGROUND: Numerous research findings support the proposed connection between such psychological characteristics as stress and hostility and the manifestation of disease. However, less evidence is available concerning the role(s) psychological factors might play in the process of disease recovery. METHODS: Eighty patients with known coronary disease and exercise-induced ischemia underwent treadmill exercise testing and 48-hour ambulatory electrocardiographic monitoring and completed a battery of standardized psychological tests assessing hostility, depression, and daily stress on four occasions during a 12-week pharmacological treatment study. After withdrawal of antiischemic drugs at baseline, patients returned for subsequent tests at 3-week intervals. During the second and third intervals, patients were prescribed one of two antiischemic medications, atenolol or amlodipine, or given a placebo. All patients were then placed on a combination treatment protocol for the 3 weeks before the final testing date. RESULTS: The combination treatment produced highly significant benefits across all measured cardiac variables (20.3% improvement in exercise performance, 13% reduction in reported angina, 64.0% reduction in the frequency of ischemic episodes; for all, p < .01). However, results showed that high baseline levels of daily stress were associated with reliably smaller treatment effects on measures of ischemia frequency and treadmill exercise time and with a significantly greater likelihood of reporting angina after treatment (r = -0.24, -0.25, and -0.33, respectively; p <.05). In addition, high baseline hostility predicted significantly smaller diastolic blood pressure improvements (r = -0.29, p < .05). CONCLUSIONS: These results indicate that psychological risk factors may have globally negative effects on the course of treatment and suggest particular factors that may warrant attention in trials targeting cardiac symptom reduction.  相似文献   
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59.
Recent advances in AIDS treatment, including the development of protease inhibitors, may eventually make AIDS a chronic disease to be managed rather than an immediately life-threatening one. This causes some psychological trauma in patients who have made financial choices based on their belief that they would die soon, and now have insufficient resources to support themselves. Others have developed survivor mentalities, and have some ambivalence about their change in status.  相似文献   
60.
P. Anderson  J. Lötvall  A. Linden 《Lung》1996,174(3):159-170
The mechanisms producing long duration of action for formoterol and salmeterol are not fully understood. The aim of the current study was to examine how the concentration of long and short acting 2-adrenoceptor agonists affects their relaxation kinetics in airway smooth muscle. Onset (time to peak relaxation) and offset of action (reassertion of reversible relaxation following repeated -adrenoceptor blockade and washout) were measured in the guinea pig trachea precontracted postjunctionally by carbachol 0.3 M in vitro. At 10–1,000% (C 1OC 1,000) of the maximally effective concentration (C 100: 150 nM formoterol, 10 M salbutamol, 30 M salmeterol), salbutamol had a shorter time to peak relaxation than did salmeterol. Formoterol and salmeterol had a similar time to peak relaxation at C 10, but, in contrast to salmeterol, formoterol's time to peak relaxation became markedly shorter and similar to that of salbutamol as the concentration was increased up to C 1,000. Significant reversible reasserted relaxation was demonstrated for salmeterol alone at C 10. At C 30C 1,000, however, salmeterol produced irreversible relaxation only, in spite of repeated -adrenoceptor blockade by sotalol 10 M followed by washout. In contrast, formoterol produced an increasing reversible reasserted relaxation at C 30C 1,000. Salbutamol produced significant, reversible reasserted relaxation at C 1,000 only. In conclusion, the concentration determines the onset and offset of action for formoterol and to a lesser extent for salbutamol, but not for salmeterol. To cause sustained action, a submaximally effective concentration is sufficient for salmeterol, whereas formoterol requires a maximally effective concentration. The rank order of concentration dependence for the relaxation kinetics is not paralleled by the rank order of lipophilicity for formoterol, salbutamol, and salmeterol. Therefore, factors other than lipophilicity may also play a role in determining the relationship between concentration and relaxation kinetics for the investigated 2-agonists. Offprint requests to: Anders Linden, MD, PhD  相似文献   
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