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71.
Electroencephalogram (EEG) recordings were made from 26 pairs of monozygotic (MZ) and 26 pairs of dizygotic (DZ) adult male twins, before and after alcohol ingestion. After a baseline EEG and a light breakfast, 1.2 ml/kg of ethanol was given orally over 15 min and the EEG repeated four times at hourly intervals. Alcohol caused a significant drop in the percentage of beta waves (14-30 cycles/sec) during the 1st hr. For the percentage of beta waves in 38 pairs of twins with complete data, MZ twin beta-wave intraclass correlations (RMZ) ranged between 0.85 and 0.91 before and after alcohol, but the DZ intraclass correlations (RDZ) started at 0.54 and fell to 0.05 at 2 hr after alcohol before recovering to baseline levels. These correlations resulted in heritability estimates [2(RMZ-RDZ)] of 0.68 at baseline and 1.73 at 2 hr. A heritability of 1.43 was found for the 1st hr drop in percentage of beta waves (RMZ = 0.78, RDZ = 0.06). These unrealistically high heritabilities, due to RDZ's approaching 0.0, suggest a failure of assumptions in the linear twin model that was used. Also, these findings are similar to, but more exaggerated than, findings in resting EEG's and visually evoked EEG potentials of twins and are compatible with the influence of gene interactions.  相似文献   
72.
An extrachromosomal nucleic acid element was detected in high-molecular-weight DNA preparations formBabesia equi merozoites. This extrachromosomal element was shown to be DNA rather than RNA and had an apparent fragment size of about 9 kilobasepairs (kb). Hybridization experiments using purified 9-kb DNA as a probe revealed sequence homologies with extrachromosomal DNA from two otherBabesia species.  相似文献   
73.
Immunology     
A selection of interesting papers that were published in the two months before our press date in major journals most likely to report significant results in immunology.  相似文献   
74.
During the 30-month period from March 1, 1988, through August 31, 1990, image-guided aspirations of 183 solitary occult breast masses, which were considered possible cysts, were performed. Indications for aspiration included (1) mass on mammography, either invisible on ultrasonography or with features atypical of a cyst, in 111 patients; (2) enlarging solitary mass on mammography with ultrasonic features suggesting a cyst in 45 patients; and (3) mammographic mass with features typical of a cyst in 27 patients, with confirmation requested by the referring physician. Of the group, 151 (83%) lesions were fluid-filled and 32 (17%) were solid. All aspirates had normal cytologic features. Of the 32 aspirates found to be solid, 19 were subsequently removed after wire localization and 13 were unchanged on mammography for a minimum of 6 months after aspiration. This is a simple and safe procedure, confirming the innocuous nature of an occult solitary breast cyst, and obviates the need for surgical biopsy.  相似文献   
75.
Patients treated for sporadic and hereditary medullary thyroid carcinoma (MTC) have varying rates of persistent disease, recurrence, and survival. The aim of this study was to correlate the immunoreactivity of the monoclonal antibody CD15 (LeuM1) to initial clinical findings and the outcome of treatment. The primary tumors of 75 patients with sporadic MTC, 7 with hereditary disease, and 3 members of MEN 2A families were studied. Of these subjects 74 (87%) showed no or little immunoreactivity (<15% positive cells; score 0) in most tumors. The remaining 13% had surgery for tumors with more than 15% cells with positive staining (score I). There was no correlation between LeuM1 immunoreactivity and sex, age, and type of MTC. There was, however, a significant correlation with the pTNM classification and UICC staging. The prognosis for patients with score 0 was significantly better than score 1 patients. CD15 immunoreactivity appears to be a predictive factor in sporadic and hereditary MTC. Lymph node dissection seems to be more successful in patients with score 0 tumors than in those with score 1 tumors. The question of reoperation in patients with recurrence of disease (especially with biochemical recurrence or persistence) should be discussed on the basis of CD15 immunoreactivity.
Resumen Los pacientes tratados para carcinoma medular, esporádico y hereditario, de la glándula tiroides (CMT) exhiben grandes variaciones en las tasas de enfermedad persistente, recidiva y sobrevida. El propósito del presente estudio fue establecer la correlación entre la inmunorreactividad del anticuerpo CD15 (LeuM1) y los hallazgos clínicos iniciales, así como con el resultado final del tratamiento.Se estudiaron los tumores primarios de 75 pacientes con CMT esporádico, de siete con enfermedad hereditaria y de 3 miembros de familias con síndrome NEM2A.Setenta y cuatro pacientes (87%) exhibieron ninguna o muy baja inmunorreactividad (menos de 15% de células positivas; puntaje 0) en la mayoría de los tumores. El 13% restante fue sometido a cirugía por tumores con más de 15% de las células con coloración positiva (puntaje 1). No se evidenció correlación entre la inmunorreactividad LeuM1 y el sexo, edad o tipo del CMT. Sin embargo, sí apareció una correlación significativa con la clasificiación pTNM y la estadificación de la UICC. El pronóstico de los pacientes con puntaje 0 resultó significativamento mejor que el de los pacientes con puntaje 1.La inmunorreactividad CD15 parece ser un factor de predicción de pronóstico en el CMT esporádico y familiar. La disección ganglionar parece ser más exitosa en pacientes con tumores de puntaje 0 que en los que portan tumores con puntaje 1.El interrogante en cuanto a reoperación en pacientes con recidiva de la enfermedad (especialmente cuando hay recidiva o persistencia bioquímica) debe ser considerada con base en la inmunorreactividad CD15.

Résumé Les taux de maladie persistante, de récidive et de survie chez des patients traités pour cancer médullaire sporadique et héréditaire de la thyroïde (CMT) sont très variables. Le but de cette étude a été de corréler l'immunoréactivité des anticorps monoclonaux CD15 (LeuM1) à des données cliniques initiales et l'évolution finale du traitement des CMT. On a étudié 75 patients ayant un CMT primitif, sept ayant une maladie héréditaire, et trois membres d'une famille MEN 2A. Soixante quatre patients (87%) avaient peu ou pas d'immunoréactivité (moins de 15% de cellules positive: score = 0). Les 13% restants ont eu une chirurgie pour les tumeurs ayant un pourcentage > 15 (score = 1). Il n'y avait aucune corrélation entre l'immunoréactivité LeuM1 et le sexe, l'âge et le type de CMT. Il y avait, en revanche, une corrélation significative entre la classification pTMN et le stage UICC. Le pronostic des patients ayant un score = 0 était significativement meilleur que celui des patients ayant un score = 1. L'immunoréactivité CD15 apparaît comme étant un facteur pronostique des CMT. Le curage lymphatique


Members and institutions are listed in Table 1.  相似文献   
76.
77.
Crohn's disease is a complex disorder, with multiple genetic traits. A frameshift mutation (Leu1007fsinsC) and two missense mutations (Gly908Arg and Arg702Trp) in the NOD2/CARD15 gene are strongly associated with susceptibility to Crohn's disease. The presence of one of these risk alleles confers a 2- to 4-fold increase in the risk of developing Crohn's disease, and the presence of two mutant alleles increases the risk over 20-fold. To facilitate the analysis of these polymorphisms, we developed three LightCycler assays to detect the missense mutations Arg702Trp and Gly908Arg and the frameshift mutation Leu100fsinsC in the NOD2/ CARD15 gene. All three assays can be run simultaneously on one LightCycler using identical cycling parameters. Analysis of 53 DNAs from Crohn's patients helped to identify carriers at allele frequencies similar to other Caucasian populations. The sequencing of such DNAs confirmed the accuracy of the assays. In conclusion, we present three rapid and robust assays to detect the Arg702Trp, the Gly908Arg and the Leu1007fsinsC ins mutations in the NOD2/CARD15 gene [corrected]  相似文献   
78.
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80.
Heart failure is a complex clinical syndrome. There is evidence for a genetic contribution to the pathophysiology of heart failure. Considering the fundamental role of neurohormonal factors in the pathophysiology and progression of cardiac dysfunction and hypertrophy, variants of genes involved in this system are logical candidate genes in heart failure. In this report, genetic polymorphisms of the major neurohormonal systems in heart failure will be discussed. Studies on polymorphisms of the renin-angiotensin-aldosterone system (RAAS), adrenergic receptor polymorphisms, endothelin (receptor) polymorphisms, and a group of miscellaneous polymorphisms that may be involved in the development or phenotypic expression of heart failure will be reviewed. Research on left ventricular hypertrophy is also included. The majority of genetic association studies focused on the ACE I/D polymorphism. Initial genetic associations have often been difficult to replicate, mainly due to problems in study design and lack of power. Promising results have been obtained with genetic polymorphisms of the RAAS and sympathetic system. Considering the evidence so far, a modifying role for these polymorphisms seems more likely than a role of these variants as susceptibility genes. Besides the need for larger studies to examine the effects of single nucleotide polymorphisms and haplotypes, future studies also need to focus on the complexity of these systems and study gene-gene interactions and gene-environment interactions.  相似文献   
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