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81.
Autologous airway epithelial cells have been used in clinical tissue‐engineered airway transplantation procedures with a view to assisting mucosal regeneration and restoring mucociliary escalator function. However, limited time is available for epithelial cell expansion due to the urgent nature of these interventions and slow epithelial regeneration has been observed in patients. Human airway epithelial cells can be expanded from small biopsies or brushings taken during bronchoscopy procedures, but the optimal mode of tissue acquisition from patients has not been investigated. Here, we compared endobronchial brushing and endobronchial biopsy samples in terms of their cell number and their ability to initiate basal epithelial stem cell cultures. We found that direct co‐culture of samples with 3T3‐J2 feeder cells in culture medium containing a Rho‐associated protein kinase inhibitor, Y‐27632, led to the selective expansion of greater numbers of basal epithelial stem cells during the critical early stages of culture than traditional techniques. Additionally, we established the benefit of initiating cell cultures from cell suspensions, either using brushing samples or through enzymatic digestion of biopsies, over explant culture. Primary epithelial cell cultures were initiated from endobronchial biopsy samples that had been cryopreserved before the initiation of cell cultures, suggesting that cryopreservation could eliminate the requirement for close proximity between the clinical facility in which biopsy samples are taken and the specialist laboratory in which epithelial cells are cultured. Overall, our results suggest ways to expedite epithelial cell preparation in future airway cell therapy or bioengineered airway transplantation procedures.  相似文献   
82.
83.
AIDS and Behavior - Evidence-based adherence counseling interventions must be delivered with fidelity to ensure that their effectiveness is retained, but little is known regarding how counselors in...  相似文献   
84.
AIDS and Behavior - To assess PrEP service delivery preferences among Black cis-gender women living in urban and rural settings in Alabama, we conducted a cross-sectional discrete choice experiment...  相似文献   
85.
In this study, we have investigated in vivo the time-dependent effects of TSH on vascular endothelial growth factor (VEGF) production in patients monitored for thyroid carcinoma. Serum VEGF, thyroglobulin (Tg), and TSH levels were assayed at baseline and 6, 24, 30, 48, 72, and 96 h and 1 wk after administration of recombinant human TSH (rhTSH) in 45 thyroidectomized patients affected by differentiated thyroid carcinoma. At baseline, the patients with metastasis (18 cases) showed serum Tg and VEGF values significantly higher than those seen in the cured patients (27 cases). During rhTSH stimulation, the mean VEGF levels decreased significantly in both patient groups. In 60% of patients with metastasis, VEGF nadir occurred at the same time as serum TSH reached the highest values, whereas in 85.7% of the cured patients VEGF decreased after the TSH peak (P = 0.003). In conclusion, we demonstrate for the first time that short-term administration of rhTSH in patients monitored for differentiated thyroid carcinoma induces a significant reduction in serum VEGF values even in the absence of thyroid tissue. This result would suggest that TSH may be able in vivo to regulate VEGF production from tissues other than the thyroid gland.  相似文献   
86.
Single oral high-dose vitamin D3 prophylaxis in the elderly   总被引:1,自引:0,他引:1  
A poor vitamin D status is common in the elderly during the winter months. Because it is possible that hypovitaminosis D may be a cause of senile osteopenia, a simple method of prophylaxis would be useful. The single, oral, high-dose method was tested in two old-age homes, and the efficacy of vitamin D3 was compared with that of 25-hydroxyvitamin D3 (25-OHD3). The trials showed that 25-OHD3 caused a higher peak value in the serum 25-OHD levels in the second week than did vitamin D3. However, follow-up after four to five months showed that in those patients who received a single, oral dose of 25-OHD3, the serum 25-OHD levels had returned to the baseline low values, whereas in those patients who had had oral vitamin D3, the serum 25-OHD levels still remained significantly raised compared with the baseline values and were within normal limits. It is concluded that the single, oral, high-dose method using vitamin D3 is a safe and simple method of prophylaxis and could be used easily in large populations of elderly persons.  相似文献   
87.
Leka, a New Platelet Antigen Absent in Glanzmann''s Thrombasthenia   总被引:1,自引:0,他引:1  
The serum of a patient who developed a posttransfusion purpura contained antibodies directed against a previously undescribed platelet antigen Lek a. The antiplatelet activity was present in the IgG fraction and was detected by immunofluorescence, 51Cr lysis and 14C-serotonin release. The frequency of the Lek a phenotype in the French population is 98.18%. Lek a does not appear to be sex-linked and seems to be closely related to the Bak a antigen. The Lek a antigen is not expressed on thrombasthenic platelets but is found on platelets from patients with the Bernard-Soulier syndrome which suggests that this antigen is carried by platelet glycoproteins IIb and/or IIIa.  相似文献   
88.
Background: The effects of systematic sports training during childhood and adolescence on subsequent growth and sexual maturation remains in dispute.

Aim: The study aimed to determine whether moderate–high volumes of dance training adversely influence linear growth and sexual maturation of young girls progressing through puberty.

Subjects and methods: This 3-year mixed longitudinal study comprised 82 novice dancers and 61 controls, aged 8–11 years at baseline, who were assessed bi-annually for 3 consecutive years. A biological maturational age was determined by estimating attainment of age at peak height velocity (PHV). Body dimensions were measured by anthropometry, and exercise levels, nutritional intake and age at menarche by questionnaires.

Results: Controls had significantly greater unadjusted height velocity than dancers 1 year before PHV, however there was no difference between groups in age of attainment of PHV. When controlling for maturation, lean mass, fat mass and extracurricular sport (excluding dancing), there were no group differences in absolute growth or velocity of growth in height, sitting height or leg length. Within the dancers there were no effects of years of dancing (>6.5 years) or weekly dance hours (>7?h per week) on growth velocities. No association was found between age at menarche and years or hours of dance training.

Conclusion: Results suggest that moderate–high levels of dance training do not affect linear growth and maturation. Thus, girls should not be discouraged from dance participation on the basis of potential growth delays.

Résumé. Arrière plan: On reste partagé sur les effets que l’entraînement sportif systématique pendant l’enfance et l’adolescence, peut avoir sur la croissance et sur la maturation sexuelle.

Objectif: L’étude cherche à savoir si l’entraînement moyen ou intensif à la danse, influence négativement la croissance linéaire et la maturation sexuelle des filles en cours de puberté.

Sujets et méthodes: Cette étude semi longitunale de trois ans impliquait 82 danseuses novices et 61 contrôles, âgées de 8 à 11 ans au départ, qui ont été examinées deux fois par an pendant trois années consécutives. Un âge de maturation biologique a été déterminé en estimant à quel âge survenait la croissance staturale de pic (CSP). Les dimensions corporelles ont été mesurées par anthropométrie et les niveaux d’activité physique, ainsi que l’alimentation et l’âge aux premières règles, ont été renseignés par questionnaires.

Résultats: Les contrôles présentent une croissance staturale non ajustée significativement plus élevée que celle des danseuses, un an avant la CSP, mais il n’y a cependant pas de différence d’âge d’atteinte de la CSP entre les groupes. A maturation, masse maigre, masse grasse et sport non programmé constants (à l’exclusion de la danse), il n’y a pas de différences entre les groupes, ni en croissance absolue, ni en vélocité de croissance staturale, taille assis ou longueur de la jambe. Parmi les danseuses, on n’observe aucun effet du nombre d’années de danse (>6,5 ans) ou du nombre d’heures de danse hebdomadaire (>7h par semaine) sur les vitesses de croissance. On n’a pas trouvé d’association entre le nombre d’heures d’entraînement à la danse et l’âge aux premières règles.

Conclusion: Les résultats suggèrent que des niveaux d’entraînement à la danse de modérés à élevés n’affectent pas la croissance linéaire ni la maturation. Les filles ne doivent donc pas être dissuadées de pratiquer la danse sur la crainte d’un retard de croissance potentiel.

Zusammenfassung. Hintergrund: Die Wirkung systematischen sportlichen Trainings während Kindheit und Adoleszenz auf das folgende Wachstum und die sexuelle Reifung wird noch kontrovers diskutiert.

Ziel: Das Ziel der Untersuchung war die Bestimmung, ob mäßig bis sehr intensives Tanztraining einen nachteiligen Einfluss auf das lineare Wachstum und die sexuelle Reifung junger Mädchen während ihrer pubertären Entwicklung hat.

Probanden und Methoden: Diese dreijährige, gemischt longitudinale Studie umfasste 82 neu anfangende Tänzerinnen und 61 Kontrollen, die zu Beginn der Studie 8 bis 11 Jahre alt waren und hernach in 6-montigen Abständen für 3 weitere Jahre untersucht wurden. Ein biologisches Reifealter wurde durch Schätzung des Alters zum Zeitpunkt der maximalen Wachstumsgeschwindigkeit (peak height velocity, PHV) bestimmt. Körpermaße wurden mittels Anthropometrie bestimmt, sowie sportliche Leistung, Ernährung und Menarchealter mittels Fragebogen.

Ergebnisse: Unkorrigiert hatten Kontrollen eine signifikant größere Wachstumsgeschwindigkeit als Tänzerinnen ein Jahr vor PHV, allerdings gab es keinen Unterschied zwischen den Gruppen hinsichtlich des Alters bei Erreichen der PHV. Wenn für Reifestatus, fettfreie Körpermasse, Fettmasse und zusätzliche sportliche Aktivität (neben dem Tanzen) korrigiert wurde, gab es keine Gruppenunterschiede mehr hinsichtlich der absoluten Zunahme oder der Wachstumsgeschwindigkeit von Körperhöhe, Sitzhöhe oder Beinlänge. Unter den Tänzerinnen gab es keine Unterschiede hinsichtlich der Anzahl der Tanzjahre (>6,5?Jahre) oder der wöchentlichen Tanzstunden (>7?h?pro Woche) auf die Wachstumsgeschwindigkeit. Es wurden keine Beziehungen zwischen Menarchealter und der Anzahl der Tanzjahre oder der wöchentlichen Tanztrainingsstunden gefunden.

Zusammenfassung: Die Ergebnisse sprechen dafür, dass ein mäßig bis sehr intensives Tanztraining keinen Einfluss auf lineares Wachstum und körperliche Reifung hat. Aus diesem Grunde sollten Mädchen nicht von der Teilnahme am Tanzen abgeschreckt werden, nur weil eine mögliche Beeinträchtigung des Wachstums befürchtet wird.

Resumen. Antecedentes: Los efectos del entrenamiento deportivo sistemático durante la infancia y adolescencia sobre el crecimiento y la maduración sexual siguen siendo objeto de debate.

Objetivo: El estudio intenta determinar si los niveles moderados y/o altos de entrenamiento en danza influyen adversamente sobre el crecimiento lineal y la maduración sexual de las chicas jóvenes que están progresando hacia la pubertad.

Sujetos y métodos: Este estudio semi-longitudinal de 3 años de duración incluía a 82 bailarinas principiantes y 61 controles, de entre 8 y 11 años de edad como punto de comparación, que fueron estudiadas bianualmente durante tres años consecutivos. La edad biológica de maduración se determinó estimando la edad a la que se alcanzaba el pico de velocidad en el crecimiento estatural (PHV). Las dimensiones corporales fueron medidas por antropometría, y los niveles de ejercicio, la ingesta nutricional y la edad de menarquia mediante cuestionarios.

Resultados: Las chicas control tenían velocidades estaturales no ajustadas significativamente mayores que las bailarinas 1 año antes del PHV, aunque no había diferencias significativas entre los grupos en cuanto a la edad a la que se alcanzaba el PHV. Cuando se controlaba para la maduración, la masa magra, la masa grasa y el deporte extra-curricular (excluyendo la danza), no había diferencias entre los grupos en el crecimiento absoluto o en la velocidad de crecimiento en estatura, talla sentado o longitud de la pierna. Entre las bailarinas, no había efectos debidos a los años que llevaban bailando (> 6,5 años) o las horas de baile semanales (> 7 horas/semana ) sobre las velocidades de crecimiento. No se encontró ninguna asociación entre la edad de menarquia y los años u horas de entrenamiento en danza.

Conclusión: Los resultados sugieren que los niveles moderados y/o altos de entrenamiento en danza no afectan ni al crecimiento lineal ni a la maduración. Por tanto, las chicas no deberían renunciar a practicar danza basándose en supuestos retrasos de su potencial de crecimiento.  相似文献   
89.
Archives of Women's Mental Health - A Correction to this paper has been published: https://doi.org/10.1007/s00737-021-01122-7  相似文献   
90.
New photoinitiating systems based on a polyoxometalate (POM) are proposed: phosphomolybdic acid in combination with silane, germane, or iodonium salt can be used to generate silyl, germyl, or phenyl radicals as well as silylium cations. The photochemical mechanisms are studied by steady‐state photolysis and electron spin resonance. The phosphomolybdic acid/silane/iodonium salt system can initiate either the radical photopolymerization of acrylates or the cationic photopolymerization of epoxides. The synthesis of interpenetrated polymer networks can also be carried out. The mechanical properties of the synthesized polymers are affected by the presence of POM in the matrix, as shown by their dynamic mechanical analysis (DMA).

  相似文献   

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