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21.
Abstract Whiplash injury of the cervical spine is a frequent issue in medical expertises and causes enormous consequential costs for motor insurance companies. Some authors accuse posttraumatic changes of alar ligaments to be causative of consequential disturbances, although biomechanical experiments achieve contradictory results and neuropsychiatric studies do not support this thesis. MRI provides excellent visualization of alar ligaments. However, signal alterations of alar ligaments must be differentiated from common normal variants. Functional MRI provides no diagnostic yield.   相似文献   
22.
Morton J Kern 《Catheterization and cardiovascular interventions》2007,70(3):469; author reply 470-469; author reply 471
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A modified exeimer laser energy delivery system was used to irradiate 100 segments of normal and fibrous aorta in vitro. The laser beam was scanned into 8 fiber bundles consisting of 50 fibers each resulting in a reduction of the applied pulse energy. The total repetition rate was increased to 150 Hz in order to keep the repetition rate per fiber bundle close to 20 Hz and to minimize thermal injury. The results demonstrate that effective ablation (etch rate per 8 pulses > 2.0 μm) occurred at an energy fluency of 50 mJ/mm2 in both normal and fibrous aorta. Tissue damage (carbonization, tissue separation, fissures, cracks, and vacuolization) was in a range of 100 ± 28 to 152 ± 30 μm for normal aorta and in a range of 57 ± 35 to 110 ± 39 μm for fibrous aorta. We conclude that effective ablation of normal and fibrous human aorta can be achieved by the application of smooth excimer laser coronary angioplasty. This improvement of excimer laser technology may result in a reduction of shock wave- and cavitation-induced damage leading to a reduction of tissue injury. However, this awaits further in vitro and in vivo confirmation. © 1993 Wiley-Liss, Inc.  相似文献   
24.
Subjective work noise: A major risk factor in myocardial infarction   总被引:5,自引:0,他引:5  
Summary The relationship between subjective work noise exposure and the risk of myocardial infarction (MI) was assessed in a population based casecontrol study. 395 MI patients (31–65 years) were compared to 2148 controls from a random population sample with the same age/sex distribution. The relative risk (RR) for MI—adjusted for control variables (smoking, age, social status, etc.)—was found to increase significantly and steadily with noise category. Subjective work noise exposure was the second greatest risk factor for MI after smoking. Possible bias due to overreporting of subjective noise exposure is discussed. Interdisciplinary studies on the relationship between cardiovascular diseases and workrelated stressors including subjective and objective noise assessment are needed to quantify the risk of MI due to work noise.
Zusammenfassung In einer bevölkerungsbezogenen Fall-Kontroll-Studie wurde der Zusammenhang zwischen der subjektiven Arbeitslärmbelastung und dem Herzinfarktrisiko untersucht. 395 Herzinfarktpatienten im Alter von 31 bis 65 Jahren wurden mit 2148 Kontrollpersonen aus einer Zufallsstichprobe mit gleicher Alters- und Geschlechtsverteilung verglichen. Das relative Risiko für Herzinfarkt—adjustiert bezüglich mehrerer Einflussvariablen wie Rauchen, Alter, Sozialstatus usw.—stieg signifikant und monoton mit der Arbeitslärmbelastung an. Die subjektive Arbeitslärmbelastung erwies sich als der zweitwichtigste Risikofaktor für Herzinfarkt nach dem Rauchen. Mögliche Fehler wie z.B. Überbewertung der subjektiven Lärmbelastung werden diskutiert. Interdisziplinäre Studien zum Zusammenhang zwischen kardiovaskulären Erkrankungen und arbeitsplatzbezogenen Stressoren mit Erfassung der subjektiven und der objektiven Lärmbelastung sind notwendig, um das Herzinfarktrisiko durch Arbeitslärm zu quantifizieren.

Résumé Le rapport entre la perception subjective de bruit gênant et le risque d'infarctus du myocarde (IM) fait l'objet d'une étude comparative portant sur 395 malades (IM) âgés de 31 à 65 ans et 2148 cas témoins sortis d'un sondage aléatoire parmi la population générale tout en assurant la même distribution d'âge et de sexe. II s'avère que—après la rectification exigée par les variables telles que consommation de tabac, âge, couche sociale, etc.—le risque relatif (RR) de IM augmente de manière significative et constante avec le gêne causé par le bruit au lieu de travail. Pour le IM, la perception subjective du bruit vécu au lieu de travail est le deuxième facteur de risque, son importance n'étant dépassée que par le tabagisme. Les auteurs discutent l'incidence possible d'une notification exagérée de bruit gênant. Afin de calculer le risque d' IM attributable au bruit perçu au lieu de travail, des études interdisciplinaires devraient être réalisées pour examiner les liens entre les maladies cardiovasculaires et les stresseurs liés au travail, y compris l'évaluation subjective et objective du bruit.
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Zusammenfassung Videofluorographie und Kinematographie gelten derzeit als Goldstandard für die Abkl?rung von Schluckst?rungen. Methodisch bedingt ist jedoch keine überlagerungsfreie Darstellung der anatomisch wichtigen Strukturen des Pharynx m?glich, so da? bei manchen St?rungen nicht unterschieden werden kann, ob diese pathoanatomisch oder funktionell-neurogen bedingt sind. Anhand von 3 Fallbeispielen wird dargelegt, ob und in welchem Umfang die Elektronenstrahlcomputertomographie mit ihrem hohen r?umlichen und zeitlichen Aufl?sungsverm?gen (Millisekundenbereich) diese Nachteile kompensiert. Es ist uns gelungen zu zeigen, da? die vollst?ndige und symmetrische nasopharyngeale Abdichtung durch den Passavantschen Wulst und den weichen Gaumen gew?hrleistet wird. Durch die EBT konnte die genaue anatomische Lokalisation und Ausbreitung eines lateralen hypopharyngealen Pouches dargestellt werden. Durch den Nachweis einer Kompression des oberen ?sophagussphinkters durch einen kleinen zervikalen Spondylophyten konnte eine scheinbar nur funktionell bedingte Dysfunktion weiter abgekl?rt werden. Diese Beispiele zeigen, da? die Elektronenstrahlcomputertomographie die sich funktionell ?ndernde Anatomie w?hrend des Schluckens in der Transversalschicht darstellen kann, und legen es nahe, ihre Wertigkeit auf der Basis systemischer interdisziplin?rer Untersuchungen zu evaluieren.   相似文献   
27.
Tumor necrosis factor alpha (TNF) is a key cytokine in the defense against many intracellular pathogens, including Rickettsia conorii, the causative agent of Mediterranean spotted fever (MSF). The levels of two soluble TNF receptors (sTNFR-p55 and sTNFR-p75), the extracellular domains of the two cell surface receptors for TNF, were elevated in the acute-stage plasma samples from 20 patients with serologically confirmed MSF. The median values were 3.1 and 7.8 ng/ml for sTNFR-p55 and sTNFR-p75, respectively. sTNFR values correlated significantly with plasma TNF concentrations. Patients with severe MSF had higher values for both receptor fragments than patients with nonsevere disease. The differences were statistically significant for sTNFR-p55 (median, 5.8 versus 2.0 ng/ml; P = 0.008). Given the proportionately higher values for both TNF and sTNFR-p55 in patients with severe MSF, the sTNFR-p55/TNF ratios for the two patient subgroups did not differ (P = 0.5), while the sTNFR-p75/TNF ratios were significantly different (P = 0.01), with disproportionately lower values in patients with severe disease.  相似文献   
28.
Wilson disease (WD) is a rare inherited autosomal recessive disorder caused by a defect in a metal transporting P-type ATPase, resulting in copper overload in various tissues and cells. The aim was to assess both the phenotype in Brazilian WD patients and the corresponding ATP7B genotype. Sixty subjects belonging to 46 pedigrees diagnosed as WD were included in this study. Direct sequencing of all 21 exons within ATP7B and their flanking introns was performed. Demographic, clinical, laboratory and histopathological data at the time of diagnosis were obtained. We identified twenty-five mutations, twelve of them reported for the first time. The c.3402delC mutation had the highest allelic frequency (30.8%), followed by the c.2123T>C (p.L708P) (16.7%). Exons 8 and 15 were the site of 62.5% of the mutations. The common European mutation c.3207C>A (p.H1069Q) was not present at all. Phenotype varied greatly among individuals with the same ATP7B genotype. Our data confirm the heterogeneity of ATP7B genotype in Brazilian WD patients. The mutational spectrum is compatible with the Brazilian history of Mediterranean immigration; however, new mutations, and different frequencies and phenotype associated with the previously known mutations characterize this population. Exons 8 and 15 should be preferentially screened in WD cases from Brazil. Phenotype variation among subjects with the same ATP7B genotype suggests that modifying factors play an additional role in the pathogenesis of WD.  相似文献   
29.
30.
T lymphocytes from patients with multiple sclerosis (MS) recognize multiple myelin basic protein (MBP) epitopes. This situation complicates the design of specific immunotherapies. We investigated to which extent the T cell response to MBP is heterogeneous in single subjects in terms of preferentially recognized regions of the molecule, major histocompatibility complex (MHC) restriction, and stability over time. From each of nine patients with MS, a minimum of six MBP-specific T lymphocyte lines (TLL) were assayed for the proliferative response to a panel of overlapping peptides, encompassing the whole MBP. Predominant Tcell recognitions of distinct MBP regions were present in three patients, all HLA-DR2+, independently of the clinical features of their disease. Tcell reactivity was preferentially directed to residues 16-38 in one patient. In this case the response was also stable over time, during different phases of the disease. Predominant reactivity to residues 86-99 was detected in the two other DR2+ patients. In each of the patients with other HLA-DR haplotypes (DR2?), as well as in three DR2+ non-MS donors, the Tcell response to MBP appeared to be considerably more heterogeneous. The HLA restriction element varied among TLL recognizing the same MBP region, even when raised from the same individual. The genomic HLA typing, performed on the DRB1 and DRB5 genes in the DR2+ subjects, showed no obvious correspondence between preferential responses to regions of MBP and HLA-DR2 subtypes. In this context, a simple, new method for the genomic typing of the HLA-DRB1 gene in individuals with the HLA-DR2 serological specificity is also described. We conclude that predominant and stable T cell responses to a single MBP region can be detected in some patients with MS. In these individuals, the MHC restriction of the T cell recognition of predominant regions appears to be variable. Polymorphisms of the HLA-DR2 gene products alone do not account for the selection of the dominant MBP Tcell epitope.  相似文献   
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