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81.
The treatment of severe and active Crohn's disease is currently based on immunosuppression, but also involves the management of nutrition, appropriate selection of patients for surgery, and maintenance of remission in the long term. Corticosteroids remain the drug of the first choice, particularly in the acute setting. However, there is evolving understanding of the role of other immunosuppressants and immune modifiers, as major concerns regarding side-effects and efficacy of steroids in the medium to long-term drive the search for alternatives.  相似文献   
82.
Mammals that use the ventilatory system as the principal means of increasing heat loss, i.e. that pant, show two fundamental changes in the control of breathing at raised temperatures. First, alveolar ventilation increases by more than, rather than in proportion to, the increase in CO2 production. Second, hypocapnia no longer causes apnoea. Rats do not use the ventilatory system as the principal means of increasing heat loss, so we have investigated whether rats also show these two changes at raised temperatures. Breathing was detected from diaphragmatic electromyogram (EMG) activity. Anaesthesia and hyperoxia were used to minimise behavioural and hypoxic drives to ventilation and arterial PCO2 (Pa,CO2) was controlled using mechanical ventilation. At 36.6 +/- 0.1 >C, breathing was absent as long as Pa,CO2 was held below a threshold level of 32.9 +/- 0.7 mm Hg (n = 14) under steady-state conditions. When body temperature in rats was raised above 37 >C, both fundamental changes in the control of breathing became apparent. First, at 39 >C the mean Pa,CO2 level during spontaneous breathing (39.6 +/- 5.4 mm Hg, n = 4) fell by 3.9 +/- 1.4 mm Hg (P < 0.05, Student's paired t test). Second, at 39.9 +/- 0.1 >C breathing was present when mean Pa,CO2 levels were only 18.2 +/- 1.5 mm Hg (n = 14), the lowest mean Pa,CO2 level we could achieve with mechanical ventilation. We calculate, however, that at 39.9 >C, the drive to breathe from the increased CO2 production alone would not sustain breathing below a Pa,CO2 level of 27.8 +/- 1.4 mm Hg (n = 13). In rats at raised body temperatures therefore a respiratory drive exists that is in addition to that related to the increase in CO2 production.  相似文献   
83.
In mammals that use the ventilatory system as the principal means of increasing heat loss, raising body temperature causes the adoption of a specialised breathing pattern known as panting and this is mediated by the thermoregulatory system in the preoptic area of the hypothalamus. In these species an additional respiratory drive is also present at raised body temperature, since breathing can reappear at low Pa,CO2 levels, when stimulation of chemoreceptors is minimal. It is not known whether the preoptic area is also the source of this additional drive. Rats do not pant but do possess this additional respiratory drive at raised body temperatures. We have therefore tested whether the preoptic area of the hypothalamus is the source of this additional respiratory drive in rats. Urethane anaesthesia and hyperoxia were used in eleven rats to minimise behavioural and chemical drives to breathe. The presence of the additional respiratory drive was indicated if rhythmic diaphragmatic EMG activity reappeared during hypocapnia (a mean Pa,CO2 level of 21+/-2 mm Hg, n = 11), induced by mechanical ventilation. The additional respiratory drive was absent at normal body temperature (37?C). When the temperature of the whole body was raised using an external source of radiant heat, the additional respiratory drive appeared at 40.6+/-0.5 degrees C (n = 3). In two further rats this drive was induced at normal body temperature by localised warming in the preoptic area of the intact hypothalamus. The additional respiratory drive appeared at similar temperatures to those in control rats in three rats following isolation of the hypothalamus from more rostral areas of the brain. In contrast, the additional respiratory drive failed to appear at these temperatures in three rats after isolating the hypothalamus from the caudal brainstem, by sectioning pathways medial to the medial forebrain bundle. Since the preoptic area is known to contain thermoreceptors and to receive afferents from peripheral thermoreceptors, the results show that this area is also the source of the additional respiratory drive at raised body temperature in anaesthetised rats.  相似文献   
84.
CONTEXT: Research on young people’s sexual relationships often overlooks subjective experiences and enjoyment. Perceived quality of sexual relationships may be related to gender, background characteristics, circumstances of first intercourse and subsequent sexual history. METHODS: Longitudinal data from 13–16‐year‐olds who participated in randomized trials of school sex education in either Scotland (N=5,356) or England (N=6,269) were used to examine young people’s subjective experiences of heterosexual relationships. Logistic regression models tested for associations between selected variables and pressure and regret at first intercourse, pressure and enjoyment at most recent intercourse, and three measures of relationship quality. RESULTS: Of the 42% of youth who reported having had sex by follow‐up, most assessed their first and most recent sexual relationships positively. Greater proportions of females than of males felt pressure at first sexual intercourse (19% vs. 10%), regretted their first time (38% vs. 20%) and did not enjoy their most recent sex (12% vs. 5%). Younger age at first sex was an important correlate of partner pressure and regret at first intercourse (odds ratios, 2.0 each, for those 13 or younger vs. 15–16‐year‐olds). Negative experiences were associated with less control (e.g., feeling pressure, being drunk or stoned, and not planning sex) and with less intimacy (e.g., sex with a casual partner and less frequent sex). Background social characteristics had limited influence compared with circumstances of first intercourse and subsequent sexual history. CONCLUSION: Most young people evaluated their early sexual experiences positively. The quality of relationships was enhanced by better communication and greater physical intimacy. For a vulnerable minority, however, early sexual experiences were negative. They could be protected by delaying first intercourse, restricting sexual activity to established relationships and learning skills to improve control in sexual encounters.  相似文献   
85.
The expression of cyclin D1 protein in tumour sections from 81 patients with epithelial ovarian cancer was analysed using immunohistochemistry. The tumours that overexpressed cyclin D1 in more than 10% of neoplastic cells were considered positive. Thus overexpression of cyclin D1 was observed in 72/81 (89%) of the cases examined. Protein was detected in both the nucleus and the cytoplasm in 24/81 (30%) and localized exclusively in the cytoplasm in 48/81 (59%) of the tumours. Cyclin D1 was overexpressed in both borderline and invasive tumours. There was no association between protein overexpression and tumour stage and differentiation. Furthermore, no correlation between cyclin D1 expression and clinical outcome was observed. However, in tumours overexpressing cyclin D1 (n = 72), the proportion displaying exclusively cytoplasmic localization of protein was higher in those with serous compared with non-serous histology (P = 0.004, odds ratio 4.8, 95% confidence interval 1.4-19.1). Western analysis using a monoclonal antibody to cyclin D1 identified a 36 kDa protein in homogenates from seven tumours displaying cytoplasmic only and one tumour demonstrating both nuclear and cytoplasmic immunostaining. Using restriction fragment length polymorphism polymerase chain reaction and PCR-multiplex analysis, amplification of the cyclin D1 gene (CCND1 was detected in 1/29 of the tumours demonstrating overexpression of cyclin D1 protein. We conclude that deregulation of CCND1 expression leading to both cytoplasmic and nuclear protein localization is a frequent event in ovarian cancer and occurs mainly in the absence of gene amplification.  相似文献   
86.
A pilot study on the immune response in patients with carcinoma of the head and neck has been made. The clinical behaviour of such neoplasia is reasoned as being partly determined by the immunological response. If prognosis is related to competence of the immune system then this parameter should be assessed. DNCB (di-nitro-chloro-benzene) skin sensitization and serial lymphocyte transformation studies were performed on all patients whose progress was studied for at least two years. On analysing the results of survival, patients could be divided into two groups--DNCB positive and DNCB negative. The negative patients could be further subdivided; those with a lymphocyte stimulation index of over fifteen; and those beneath this level--the former had a much better prognosis than the latter. Also, such cancer patients were shown to have both cellular and serum factors causing depression of lymphocyte transformation. In the light of all findings, a future programme of investigation is proposed.  相似文献   
87.
Interobserver variation in the interpretation of abdominal radiographs   总被引:2,自引:0,他引:2  
A total of 140 sets of abdominal radiographs were reviewed independently by four qualified diagnostic radiologists. The degree of interobserver agreement was determined by calculating kappa values for 19 commonly used radiographic signs and diagnoses. There was fair to excellent interobserver agreement for 11 signs and diagnoses and poor agreement for the remaining eight. The signs and diagnoses for which agreement is poor cannot be considered reliable and include particularly large bowel obstruction and nonspecific gas pattern.  相似文献   
88.
89.
Narcolepsy and immunity   总被引:1,自引:0,他引:1  
  相似文献   
90.
In a comparison of the effects of domperidone and carbidopa during levodopa treatment, 20 patients with idiopathic Parkinson's disease were treated with fixed dose regimens of either levodopa 500 mg-domperidone 20 mg or levodopa 100 mg-carbidopa 25 mg; each for 8 weeks. Clinical response, incidence of side effects, and plasma levodopa concentration resulting from each treatment were compared. Overall, in the dosages used, Parkinson's disease was less well controlled with levodopa-domperidone than with levodopa-carbidopa. In eight subjects there was a severe deterioration 2 to 7 days after changing from a fixed dose of levodopa-carbidopa to levodopa-domperidone. In nine subjects who completed the trial, the clinical response, occurrence of dyskinesias and of nausea and vomiting, were similar with both treatments, although peak plasma levodopa concentration and levodopa bioavailability were greater on levodopa-domperidone than on levodopa-carbidopa.  相似文献   
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