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大量文献报道,日光照射会对人皮肤造成各种损伤,例如,皮肤色素沉着问题,多种明显的面部老化征象等.与此同时,日光引起的光老化还会加速和(或)改变皮肤自然老化进程.然而,对于不同的种族,其自然老化和光老化所致的皮肤渐进性变化有差异,这些差异可以在不同种族的皮肤老化图谱、书籍中找到.2015年《中华皮肤科杂志》医学简讯栏目曾报道“日光对白种人皮肤老化可见临床征象的影响”,该研究在日光充足的法国南部招募了生活习惯不同的两组女性志愿者(“sun-seekers”与“sun-phobic”),通过对比她们面部老化征象的临床图片,发现皮肤色素沉着相关的临床参数与光老化联系最紧密,而与年龄的相关性较弱.  相似文献   
23.
Discoid lupus erythematosus is a manifestation of chronic cutaneous lupus erythematosus with a small risk of systemic involvement. In this review article, the role of predisposing factors such as haplotype, hormones, antibodies and sunlight are discussed. The clinical features, including variants and associations, and management options are presented.  相似文献   
24.
The clinical findings of Takatsubo Cardiomyopathy and acute myocardial infarction can be very similar. While Takatsubo cardiomyopathy rarely leads to severe complications, acute myocardial infarction can be life threatening. Treatment of both these conditions is different and so it is imperative for clinicians to have a high index of suspicion for either. Several EKG differences between the two entities have been proposed. This article summarizes the EKG changes most likely seen in Takatsubo cardiomyopathy and compares them to those seen in Acute Myocardial infarction.  相似文献   
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胎儿和新生儿同种异体免疫性血小板减少症(AIT)是引起胎儿和新生儿严重血小板减少的最常见原因.母亲针对源自父亲的胎儿血小板抗原的IgG抗体,在妊娠早期就可通过胎盘,通常导致胎儿严重血小板减少.由于一些血小板减少症临界值(50、100或150×109/L)的不同,他们的发生率亦各不相同.但在多数未经选择的人群中,AIT影响1/1 000到1/2 000活产数.在新生儿病房,临床确诊的重症AIT很罕见,可能只有1:10 000分娩数.  相似文献   
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Rafiq MA, Ansar M, Marshall CR, Noor A, Shaheen N, Mowjoodi A, Khan MA, Ali G, Amin‐ud‐Din M, Feuk L, Vincent JB, Scherer SW. Mapping of three novel loci for non‐syndromic autosomal recessive mental retardation (NS‐ARMR) in consanguineous families from Pakistan. To date, of 13 loci with linkage to non‐syndromic autosomal recessive mental retardation (NS‐ARMR), only six genes have been established with associated mutations. Here we present our study on NS‐ARMR among the Pakistani population, where people are traditionally bound to marry within the family or the wider clan. In an exceptional, far‐reaching genetic survey we have collected more than 50 consanguineous families exhibiting clinical symptoms/phenotypes of NS‐ARMR. In the first step, nine families (MR2‐9 and MR11) with multiple affected individuals were selected for molecular genetic studies. Two families (MR3, MR4) showed linkage to already know NS‐ARMR loci. Fifteen affected and 10 unaffected individuals from six (MR2, MR6, MR7, MR8, MR9 and MR11) families were genotyped by using Affymetrix 5.0 or 6.0 single‐nucleotide polymorphism (SNP) microarrays. SNP microarray data was visually inspected by dChip and genome‐wide homozygosity analysis was performed by HomozygosityMapper. Additional mapping was performed (to exclude false‐positive regions of homozygosity called by HomozygosityMapper and dChip) on all available affected and unaffected members in seven NS‐ARMR families, using microsatellite markers. In this manner we were able to map three novel loci in seven different families originating from different areas of Pakistan. Two families (MR2, MR5) showed linkage on chromosome 2p25.3‐p25.2. Three families (MR7, MR8, and MR9) that have been collected from the same village and belong to the same clan were mapped on chromosome 9q34.3. MR11 maps to a locus on 9p23‐p13.3. Analysis of MR6 showed two positive loci, on chromosome 1q23.2‐q23.3 and 8q24.21‐q24.23. Genotyping in additional family members has so far narrowed, but not excluded the 1q locus. In summary, through this study we have identified three new loci for NS‐ARMR, namely MRT14, 15 and 16.  相似文献   
28.
BACKGROUND: Failure to resist chronic obsessive-compulsive symptoms may denote an altered state of cognitive control. We searched for the cerebral regions engaged in this dysfunction. METHOD: Differences in brain regional activity were examined by event-related functional magnetic regional imaging (fMRI) in a group of adolescents or young adults (n = 12) with childhood-onset obsessive-compulsive disorder (OCD), relative to healthy subjects. Subjects performed a conflict task involving the presentation of two consecutive and possibly conflicting prime and target numbers. Patients' image dataset was further analysed according to resistance or non-resistance to symptoms during the scans. RESULTS: Using volume correction based on a priori hypotheses, an exploratory analysis revealed that, within the prime-target repetition condition, the OCD subjects activated more than healthy subjects a subregion of the anterior cingulate gyrus and the left parietal lobe. Furthermore, compared with 'resistant' patients, the 'non-resistant' OCD subjects activated a bilateral network including the precuneus, pulvinar and paracentral lobules. CONCLUSIONS: Higher regional activations suggest an abnormal amplification process in OCD subjects during the discrimination of repetitive visual stimuli. The regional distribution of functional changes may vary with the patients' ability to resist obsessions.  相似文献   
29.
Summary Therapeutic success in dysplasia and congenital dislocation of the hip depends on an early diagnosis. The physiopathology remains very debatable and several concepts are propounded. For a better physiopathologic understanding, the authors have carried out a study of the morphology and development of 22 pre- and neonatal hips. At first, the acetabulum is cartilaginous and distorted by the moving femoral head; this acetabulum is histologicaly affected by the femoral pressure.The pathologic hip is characterized by defective posterior bony coverage of the femoral head by the acetabulum. The acetabulum ossifies during the 3 months following birth, forming a cup-like cavity under the pressure of the femoral head. Therefore, neonatal screening tests such as sonography must take place in the first weeks of life.
Étude anatomique de la hanche antéet néonatale. Réflexions sur la physiopathologie des dysplasies et luxations congénitales de la hanche
Résumé Le succès du traitement des dysplasies et luxations congénitales de hanche est lié à la précocité du diagnostic. La physiopathologie de ces affections reste discutée et plusieurs conceptions ont pu être proposées. Les auteurs ont réalisé une étude structurale et évolutive de 22 hanches anté et néonatales afin de mieux comprendre cette physiopathologie. Dans les périodes anté- et néonatale, l'acétabulum est cartilagineux, déformable sous l'action d'une tête fémorale en mouvement et il est le siège de remainements histologiques dépendant de la pression exercée par l'épiphyse fémorale. L'ossification de l'acétabulum s'effectue lors du ler trimestre postnatal, construisant la cavité articulaire sous l'effet de la pression de la tête du fémur. Dysplasies et luxations apparaissent comme un défaut de couverture postéro-supérieure de l'épiphyse fémorale par l'acétabulum. Le dépistage d'anomalies, notamment par l'échographie, devra donc être réalisé dans les premières semaines de la vie.
  相似文献   
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