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41.
Background : Recent studies support the therapeutic utility of repetitive transcranial magnetic stimulation in Parkinson's disease (PD), whose progression is correlated with loss of corticostriatal long‐term potentiation and long‐term depression. Glial cell activation is also a feature of PD that is gaining increasing attention in the field because astrocytes play a role in chronic neuroinflammatory responses but are also able to manage dopamine (DA) levels. Methods : Intermittent theta‐burst stimulation protocol was applied to study the effect of therapeutic neuromodulation on striatal DA levels measured by means of in vivo microdialysis in 6‐hydroxydopamine‐hemilesioned rats. Effects on corticostriatal synaptic plasticity were studied through in vitro intracellular and whole‐cell patch clamp recordings while stepping test and CatWalk were used to test motor behavior. Immunohistochemical analyses were performed to analyze morphological changes in neurons and glial cells. Results : Acute theta‐burst stimulation induced an increase in striatal DA levels in hemiparkinsonian rats, 80 minutes post‐treatment, correlated with full recovery of plasticity and amelioration of motor performances. With the same timing, immediate early gene activation was restricted to striatal spiny neurons. Intense astrocytic and microglial responses were also significantly reduced 80 minutes following theta‐burst stimulation. Conclusion : Taken together, these results provide a first glimpse on physiological adaptations that occur in the parkinsonian striatum following intermittent theta‐burst stimulation and may help to disclose the real potential of this technique in treating PD and preventing DA replacement therapy‐associated disturbances. © 2017 International Parkinson and Movement Disorder Society  相似文献   
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The aim of this study is to review the literature regarding reduction pneumoplasty (RP) or lung volume reduction surgery in order to assess the state of the art of this topic. Reduction pneumoplasty is a palliative surgical therapy that is offered to selected patients with severe non-bullous emphysema not responding to maximized medical therapy. The use of staple excision or plication of the most destroyed target areas of the lung appeared to be more effective than laser ablation. Currently, a one-stage bilateral procedure is the standard of care although a unilateral reduction can be preferable in patients with asymmetric emphysema and/or if a staged bilateral treatment strategy is planned. Randomized studies have suggested that RP is superior to medical therapy including respiratory rehabilitation for improving subjective dyspnea, exercise capacity, respiratory function and quality of life for up to 1 year. In addition, few long-term studies have suggested that the improvements obtained with RP can be maintained for several years in properly selected patients. Although several issues still await a definitive answer, the available literature data and our current experience have clearly indicated that RP works well and is a safe and effective procedure for palliating symptoms and improving respiratory function in severely disabled emphysematous patients.  相似文献   
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Environmental stressors can substantially affect the adaptive response of rats to novelty in a sexually dimorphic manner. Gender-related differences are also observed in neurochemical and behavioural patterns of adult rats following prenatal exposure to diazepam (DZ). In the present study the behavioural reactivity to novelty is investigated in open field (OF) and in acoustic startle reflex (ASR) tests, in non handled (NH), short-lasting handled (SLH) and long-lasting handled (LLH) adult male and female rats prenatally exposed to DZ. A single daily s.c. injection of DZ (1.5 mg/kg) over gestation days 14-20 decreases GABA/BDZ receptor function in both sexes, as shown by the decreased electrographic hippocampal response to DZ and the increased response to picrotoxin, after intra-locus coeruleus injection of the two compounds. In OF NH DZ-exposed males display a lower total distance travelled (TDT), a higher rearing frequency (RF) and a greater number of transitions in the centre of the arena (CNT) compared to NH rats prenatally exposed to vehicle. Conversely, NH DZ-exposed females show slight changes in TDT and RF and a greater reduction in CNT and in the amount of time spent in the centre of the arena (CAT). These effects are associated with an increase in the peak amplitude of the ASR in both sexes. Short-lasting handling slightly influences DZ-evoked effects in animals of both sexes. In DZ-exposed males long-lasting handling attenuates the reduction in TDT and the enhancement in RF, prevents the increase in CNT and reduces the peak amplitude of ASR. In DZ-exposed females, long-lasting handling increases TDT and RF, induces a lower avoidance of the centre of the arena, and does not modify the peak amplitude of ASR, when compared to controls. These findings indicate that prenatal exposure to DZ differently affects behavioural reactivity in adult male and female rats, and suggest that a long-lasting handling is able to attenuate some behavioural deficits induced by prenatal DZ exposure.  相似文献   
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ABSTRACT The oral surface of the mouse palate has eight or nine pairs of transverse ridges, or rugae. Abnormalities in the pattern of palatal rugae have been reported in mutant mice and mice exposed to teratogens in utero. The purpose of this study was to describe control data of ruga variations for proper definition of "anomalous" ruga patterns. Jc1:ICR mice on gestation day 18 were killed, and the fetuses were fixed in Bouin's solution. Fetal palates were examined under a dissecting microscope. In total, 251 fetuses from 19 dams were observed. Among these fetuses 88% had one or more variations in the palatal rugae. Common variations were supernumerary anterior to the fourth ruga, division, and lateral bifurcation, and these were regarded as variations in the "normal" range. Variations rare in fetuses from untreated dams were shortness, fusion, cross, and supernumerary posterior to the fifth ruga, and these should be defined as "anomalous" ruga patterns in teratology experiments. Key words: mouse, palate, rugae, developmental toxicity test  相似文献   
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ABSTRACT Embryotoxicity and teratogenicity of 5-fluorouracil (5-FU) and modulation of its effect by N-acetyl-L-cysteine (NAC) andor phorone were evaluated in mice. Pregnant ICR mice were intraperitoneally injected with 25 mglkg of 5-FU on day 11 of gestation (vaginal plug = day 0). Pregnant mice were pretreated with NAC at dose levels of 80, 160, and 320 mg/kg injected intravenously 2 hours before dosing with 5-FU. Pregnant mice were killed on day 17 of gestation. Fetuses were examined for external malformations, especially limb malformations. Pretreatment with 160 mg/kg and 320 mg/ kg of NAC decreased the incidence and severity of oligodactyly induced by 5-FU. There was little difference in maternal body weight gain, fetal mortality, and fetal weight between the 5-FU group and the 5-FU plus NAC groups. Pretreatment with phorone, a glutathione depleting agent, at dose levels of 160 and 320 mg/kg injected intraperitoneally, 4 hours before dosing with 5-FU, increased the incidence and severity of oligodactyly induced by 5-FU. Cotreatment with NAC at dose levels of 160 and 320 mg/kg decreased the incidence and severity of oligodactyly induced by 5-FU and 80 mg/kg of phorone. Cotreatment with NAC 160 mg/kg could not suppress the augmentative effect of phorone on 5-FU teratogenicity under the severe condition, that is, the excess amount of phorone such as 320 mg/kg. These results indicate that the teratogenicity of 5-FU is mitigated with NAC pretreatment, and also the level of endogenous glutathione is one of the factors which significantly affects teratogenicity of 5-FU.  相似文献   
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