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41.
The pattern of pre- and postnatal appearance of 5-HT1D receptors throughout the different areas of the human brain was studied by quantitative in vitro autoradiography, using [125I]GTI (serotonin O -carboxymethyl-glycyl-[125I]tyrosinamide) as a ligand. The anatomical distribution of 5-HT1D receptors in neonatal, infant and children's brain was in good agreement with that observed in the adult, the basal ganglia and substantia nigra being the most intensely labelled areas. The development of these receptors throughout the human brain was mainly postnatal: low densities of [125I]GTI binding sites were observed at the fetal/neonatal stage in most regions analyzed, in contrast with the high levels of labelling found in infant and children's brains. Indeed, in a number of regions, including the globus pallidus, substantia nigra and visual cortex, a peak of overexpression of 5-HT1D receptors was observed in the first decade of life. Such overexpression could support a regulatory role for 5-HT1D receptors in advanced periods of the CNS developmental process. Our results also indicate that the administration of drugs acting on 5-HT1D receptors during the early postnatal period of life could result in modifications of their properties, as these receptors are already functional in this period.  相似文献   
42.
Adult Toxocara canis and Ascaris suum were incubated in vitro in media containing 0.1, 1, 10 or 100 µg/ml flubendazole in order to study drug-derived effects. This incubation was done for 8 h and repeated (in some groups) after 24 h for another 8 h. The onset and intensity of flubendazole-derived effects were dosage-dependent and time-dependent, i.e. the same grade of damage was reached when incubating for a longer period at a low dosage or for a shorter period in medium containing a high amount (10 or 100 µg/ml) of flubendazole. A repeated incubation in drug-containing medium was superior to a single exposure. Flubendazole is apparently able to penetrate into the worm's interior via the cuticle. This became evident in worms with sealed orifices, which showed identical damage to worms which were not sealed. The type of tissue damage due to flubendazole was identical in both worm species when exposed to any of the drug dosages used. The principal mode of action of flubendazole was based on the complete reduction of microtubuli-polymerisation inside the parasite's cells. This apparently led to the complete destruction of the hypodermis, muscle layer and intestine. Flubendazole also stopped the formation of gametes. Summarising, even low concentrations of flubendazole (0.1 µg/ml) led to significant and irreversible damage in all worms studied.  相似文献   
43.
The aim of this research was to quantify sleep problems in patients suffering from Parkinson's disease by means of the new Parkinson's Disease Sleep Scale (PDSS) and to correlate such problems with the possible influence of current drug treatment. A total of 70 patients (36 men and 34 women) with a diagnosis of Parkinson's disease were enrolled. Their mean age was 69.7 +/- 8.2 years, and duration of disease was 7.4 +/- 4.8 years. All patients completed the PDSS and the Unified Parkinson's Disease Rating Scale (UPDRS Parts I-IV). Drug consumption and doses were registered. The mean score on the PDSS scale was 109.23 +/- 19.75 and on the UPDRS III scale was 25.24 +/- 11.35. The lowest scores were obtained in Item 3 (sleep fragmentation): 5.53 (2.46); and in Item 8 (nocturia): 5.75 (2.91). There was a weak correlation between the PDSS and UPDRS III (cc = -0.355, P = 0.003), PDSS and UPDRS I (cc = -0.272, P = 0.02), and PDSS and UPDRS IV (cc = -0.416, P < 0.001). Motor conditions, mental state, and drug complications influence sleep quality. Although this effect was significant, it was not of a great magnitude. Dopaminergic drugs did not increase daytime sleepiness. As a whole, sleep quality in patients who took dopaminergic agonists did not differ from that of patients who took levodopa in monotherapy.  相似文献   
44.
Loss of heterozygosity for distal markers on 22q in human gliomas.   总被引:5,自引:0,他引:5  
Loss of constitutional heterozygosity as determined through the analysis of restriction-fragment-length polymorphism (RFLP) on tumoral and constitutional DNA has proven to be helpful to delimit the location of tumor-suppressor genes in the human genome. In malignant gliomas this approach indicates that chromosomes 9p, 10, 17p, and 22 may contain genes of this category involved in its origin and/or progression. Regarding chromosome 22, the data so far provided by molecular studies confirmed those previously reported by cytogenetic studies, suggesting the existence of a sub-group of malignant gliomas characterized by monosomy of this chromosome. However, the precise location of the putative glioma suppressor gene on chromosome 22 remains ambiguous. We have performed a combined cytogenetic and RFLP study on a series of 31 gliomas, looking for structural abnormalities of this chromosome. In 3 instances, terminal deletions of the long arm of chromosome 22 were observed by both methodologies, suggesting that the band q13 region distal to the D22S80 marker might be the critical domain non-randomly involved in tumor suppression of gliomas.  相似文献   
45.
In patients with osteogenesis imperfecta (OI), a disease characterized by abnormal bone fragility, bone mineral density (BMD) was found to be relatively preserved. Quantitative computed tomography (QCT) is the only available method for directly measuring in vivo both volumetric density and the cross-sectional area. Here we report the data from dual-energy X-ray absorptiometry DXA (spine and hip) and peripheral (pQCT) (ultradistal and proximal radius) measurement of 27 adult patients affected by OI, mostly of type I, compared with a group of healthy persons. In the patients with OI, areal BMD values at both femoral neck and lumbar spine were considerably lower than in control subjects (-32 and -36%, respectively; p<0.001 for body weight and height adjusted values). pQCT volumetric density at the ultradistal radius was 19% lower than in control subjects and this difference rose to 32% for purely cancellous bone tissue. The whole bone cross-sectional area of ultradistal radius, as measured by pQCT, was superimposable to normal. At the proximal radius, both cross-sectional area and cortical area, together with Bending Breaking Resistance Index (BBRI), were significantly lower in OI (-23; -22; -32% respectively; p<0.001 for body weight and height adjusted values), but cortical volumetric density was even slightly higher in the OI group than in control subjects. In conclusion, it appears that the most obvious defect in adults with OI is the inability to acquire an adequate thickness of the cortices of long bone and to achieve or maintain normal trabecular density.  相似文献   
46.
BACKGROUND: The use of knee ankle foot orthoses (KAFOs) to prolong independent mobility is a widely used rehabilitation strategy for children with Duchenne muscular dystrophy (DMD). AIMS: To explore views and adjustment of families with a child with Duchenne muscular dystrophy to the use of KAFOs. METHODS: interviews with families of children aged 8-18 years with DMD; questionnaires on psychiatric adjustment (SDQ for children; GHQ for parents). RESULTS: In total, 17 parents and 9 children took part. Families experienced the introduction of KAFOs as a signal for illness deterioration and a re-awakening of the feelings experienced at diagnosis. Nevertheless, the majority expressed a positive attitude and over two-thirds satisfaction with KAFOs use. High psychiatric risk was found in 2/17 children (12%; expected 10%) and 7/17 main carers (41%; expected 20-30%). CONCLUSION: Most families were satisfied with KAFOs use, and its implementation was well tolerated especially by the children. However, mental distress was high in main carers who emphasized the importance of full preparation and support in this rehabilitation technique.  相似文献   
47.
Summary:  Purpose: Temporal lobe epilepsy (TLE) is probably more difficult to recognize in children than in adults. In fact, ictal symptoms in children are less stereotyped and less obvious, and the neuropathological substrate is more heterogeneous than in adults. The aim of this study is to examine the relationships between etiology, age at onset and electroclinical findings in 77 children with TLE, 32 of whom were surgically treated.
Methods: Electroclinical study including video-EEG recording of seizures in 77 children with TLE. The investigation focused on the first five initial ictal symptoms.
Results: Age at onset was less than 3 years in 39 cases, between 3 and 6 years in 17 cases and older than 6 years in 21 cases. Auras also occurred in younger children but were more common after the age of 6 years. A peculiar initial ictal semiology consisted in staring with arrest, lip cyanosis, and very slight oral automatisms. In some cases, EEG recordings documented seizures starting independently on both temporal lobes. Based on electroclinical and neuroradiological features, we recognized three subgroups: symptomatic TLE due to cortical malformations or nonevolutive tumors, TLE with mesial temporal sclerosis, and cryptogenic TLE.
Conclusions: A correct electroclinical and neuroradiological approach allows in several cases early recognition of TLE even when onset is earlier than the age of 6 years. A correct definition of the localization relies primarily on video-EEG recording of the seizures, possibly repeated during follow up in cases lacking obvious neuroradiological correlation.  相似文献   
48.
A 34-years-old floor-layer developed optic neuropathy and motor neuron disease after being accidentally exposed to a solvent mixture containing methanol and other substances. Optic neuropathy is a complication of methanol poisoning, but the onset of a motor neuron disorder resembling amyotrophic lateral sclerosis after the exposure to these substances has not been previously described. The temporal onset of the clinical symptoms, biological plausibility, young age of the patient and absence of neurological disorders in the family history raises suspicion of a possible causative relationship.  相似文献   
49.
Treatment of chronic osteomyelitis of distal tibia is complex. It often requires the association of antibiotic therapy and a surgical procedure. This consists of exhaustive debridement of infected bone and soft tissue which must have adequate cutaneous coverage and vascular supply which enables creating a barrier to microorganisms and greater resistance to infection. Free or pedicled muscular flaps have been the techniques most often used for this type of lesions. Free flaps require a precise microsurgical technique and prolonged surgery. Pedicled muscular flaps do not provide sufficient coverage and vascularisation of the distal tibia for large size defects. The fasciocutaneous flap has been used for the treatment of coverage defects in the perimalleolar area and the heel. We report the utility of this flap as management of chronic osteomyelitis of the distal third of the tibia with complete healing of the infection and correct cutaneous coverage without complications.  相似文献   
50.
To date, few studies have examined the personality characteristics and clinical predictors of impulsive behaviors in eating disorders (ED). The aim of this work was to study the prevalence of a wide range of impulsive behaviors in a sample of 554 ED subjects and to examine the predictors of these behaviors. Subjects were diagnosed according to DSM-IV criteria as having anorexia nervosa restricting type (ANR; n = 183), anorexia nervosa binge eating/purging type (ANBP; n = 65), bulimia nervosa purging type (BNP; n = 244), and bulimia nervosa nonpurging type (BNNP; n = 62). Nine different types of impulsive behaviors were assessed in these groups. About 55% of the whole sample reported at least one type of impulsive behavior, 35% more than one, and about 13% more than three. According to findings, impulsive and multi-impulsive subjects are characterized by the presence of purging behavior and by specific temperamental features such as high levels of novelty seeking and low persistence. The prediction of impulsive behavior is further improved by considering the presence of a history of childhood abuse, maternal psychiatric morbidity, and some specific psychological symptoms such as maturity fears, perfectionism, depression, and obsessive-compulsive symptoms. The presence of impulsive behavior appears to be associated with overall higher levels of psychiatric symptomatology and eating psychopathology, thus indicating that they are an important feature to be considered in the assessment and treatment of ED.  相似文献   
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