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91.
Annals of Surgical Oncology - The liver-first approach in patients with synchronous colorectal liver metastases (CRLM) has gained wide consensus but its role is still to be clarified. We aimed to...  相似文献   
92.
Summary and Conclusions In 12 patients with increased intracranial pressure, caused by an expanding process, a hypertonic urea solution was intravenously administered during a craniotomy. At different times before, during and after the operation, the electrolytes, urea, glucose and total protein values were determined in various body fluids and tissues.This study disclosed that the urea administered was distributed through both the intracellular and the extracellular space after 20 minutes. The values of the electrolytes, except the calcium, in the extracellular fluid remained constant after administration of the urea solution; the total protein value, however, showed a considerable decrease.It was established that the blood-brain barrier plays no appreciable role in the mechanism of action of hypertonic urea solutions in dehydrating the brain tissue; the blood-C. S. P. and brain-C. S. F. barriers may do.
Zusammenfassung Bei 12 Patienten mit intrakranieller Drucksteigerung infolge eines raumbeengenden Prozesses wurde Harnstofflösung intravenös während der Schädeleröffnung gegeben. Zu verschiedenen Zeitpunkten vor, während und nach der Operation wurden Elektrolyt, Harnstoff, Glukose und Gesamteiweiß quantitativ bestimmt und zwar sowohl in verschiedenen Körperflüssigkeiten wie auch in Geweben.Die Untersuchungen ergaben, daß der verabfolgte Harnstoff in 20 Minuten sich sowohl auf den intrazellulären, wie den extrazellulären Raum verteilt hat. Die Elektrolytwerte, mit Ausnahme von Kalzium, blieben nach der Harnstoffinfusion in den extrazellulären Flüssigkeiten unverändert, der Gesamteiweißwert nahm dagegen beträchtlich ab.Es wurde festgestellt, daß die Bluthirnschranke keine wesentliche Rolle für die entwässernde Wirkung des Harnstoffes auf das Hirngewebe spielt, während die Blut-Liquor-Schranke und die Hirn-Liquor-Schranke vielleicht von Bedeutung sind.

Resumen Después de una craniectomía se administró una solución de urea hipertónica por via intravenosa a 12 pacientes que presentaban una presión intracraneal creciente a causa de una exposición de la hipófisis. Periódicamente, antes, durante y después de la operación se determinaron los valores de los electrolitos, de la urea, de la glucosa y de las proteinas totales en los diferentes líquidos y tejidos del organismo.Este estudio demostróque la urea administrada se distribuia a través del espacio intra y extracelular al cabo de 20 minutos. Los valores de los electrolitos, excepto el calcio, permanecieron constantes en el líquido extracelular después de la administración de la solución de urea; el valor de las proteinas totales, sin embargo, mostró un descenso considerable.Se concluyó que la barrera hemato-encefálica no juega ningún papel apreciable en los mecanismos de acción de las soluciones de urea hipertónica en la deshidratación del tejido cerebral; tal vez lo juegue en las barreras sangre-liquido cofalo-raquídeo y cerebro-líquido cefalo-raquídeo.

Résumé Lors d'une craniotomie, une solution d'urée hypertonique fut administrée par voie intraveineuse chez 12 patients présentant une pression intracrânienne grandissante causée par une expansion de l'apophyse. De temps en temps, avant, pendant et après l'opération, les valeurs des électrolytes, de l'urée, du glucose et de la protéine totale étaient déterminées dans les différents liquides et tissus du corps.Cette étude démontra que l'urée administrée était distribuée à travers l'espace intra et extraecllulaire au bout de 20 minutes. Les valeurs des électrolytes, excepté le calcium, demeurèrent constantes dans le liquide extracellulaire après l'administration de la solution d'urée; la valeur de la protéïne totale, pourtant, montrait une baisse considérable.Il fut établi que la barrière hémato-encéphalique ne joue aucun rôle appréciable dans le mécanisme d'action des solutions d'urée hypertonique dans la déshydratation du tissu cérébral; les barrières sang-liquide céphalorachidien et cerveau-liquide céphalo-rachidien, peut-être.

Riassunto In 12 pazienti con ipertensione endocranica, causata da un processo espansivo, è stata somministrata durante la craniotomia dell'urea in soluzione ipertonica per via venosa. A diversi tempi prima, durante e dopo l'intervento, sono stati dosati gli elettroliti, l'urea, il glueosio e le proteine totali in vari fluidi e tessuti corporei. Queste ricerche hanno evidenziato che l'urea viene distribuita tra spazio intracellulare ed extracellulare in 20 minuti. I livelli degli elettroliti, eccetto il calcio, rimangono costanti nel liquido extracellulare dopo la somministrazione di urea, i valori della proteinemia totali invece mostrano una notevole diminuizione.E' stato stabilito che la barriera emato-cerebrale non gioca alcun ruolo apprezzabile nel meccanismo d'azione dell'urea ipertonica nel disidratare il tessuto cerebrale; un ruolo importante potrebbe essere inveoe giocato dalla barriera emato-liquorale e tra liquor e sistema nervoso.


This study was supported by a grant from the Netherlands Organization for the Advancement of Pure Research (Nederlandse Organisatie voor Zuiver-Wetenschappelijk Onderzoek, Z. W. O.).  相似文献   
93.
Previous research has shown that mytilins and MGDs are two types of 4-kDa, cysteine-rich, cationic antimicrobial peptides, which are abundant in hemocytes of the mussels, Mytilus galloprovincialis and M. edulis. The expression of the genes encoding these peptides has been analyzed in the hemocytes of animals subjected to various stress factors, as well as during larval development. Variations in gene expression in adult mussels have been tested under conditions of physical stress, bacterial challenge and heat shock. The results suggest that in adult mussels, the MGD2 gene may be over-expressed with physical and temperature stress, but that reduced expression occurs with bacterial challenge. Gene expression during development has been analyzed using different larval and post-larval stages, ranging from 4-day-old veliger larvae to 32-day-old post-larvae. The results show that the expression of both mytilin B and MGD2 is developmentally regulated, but neither gene is expressed in mussels until after larval settlement and metamorphosis. Finally, the genes encoding two isoforms of these peptides have been cloned and sequenced, revealing that both genes contain four exons and three introns.  相似文献   
94.
Effects of dietary naturally occurring anticarcinogens; quercetin, flavone, ellagic acid, ferulic acid, tannic acid, curcumin, coumarin, alpha-angelicalactone, fumaric acid and Brussels sprouts on male Wistar rat hepatic and intestinal (i) glutathione S-transferases (GST) enzyme activity, (ii) GST isozyme levels and (iii) glutathione (GSH) content were investigated. GST enzyme activity was significantly increased by all anticarcinogens tested, except fumaric acid, at least at one of the five sites investigated: proximal, middle, distal small intestine, large intestine and liver. Only alpha-angelicalactone gave an enhanced GST enzyme activity at all five sites. Large intestinal GST enzyme activity was increased only by quercetin (175%) and alpha-angelicalactone (138%). Concomitant changes in GST isozyme levels occurred. Class alpha GSTs were induced in 50% of the cases, especially in liver and upper parts of the intestine by quercetin, flavone, coumarin and alpha-angelicalactone. GST class pi levels were enhanced only at one site by quercetin, coumarin and alpha-angelicalactone. GST class mu changed in 14% of the cases, most profoundly in proximal and middle small intestine by flavone, coumarin and alpha-angelicalactone. Tannic acid and fumaric acid gave a significant raise in class alpha GSTs at almost all sites, whereas overall GST enzyme activity hardly changed. GSH was increased at various sites in 14% of the cases by Brussels sprouts, quercetin, flavone and alpha-angelicalactone. These data demonstrate that most anticarcinogens, in particular flavone, coumarin and alpha-angelicalactone, enhance GST activity in liver and intestine, mainly by induction of class alpha and mu isozymes.  相似文献   
95.
BACKGROUND: Food in the intestine drives the enterohepatic circulation of bile components. OBJECTIVE: We investigated whether parenteral or enteral delivery of nutrients alters serum and biliary lipids in critically ill patients. DESIGN: Eight intensive care unit (ICU) patients who had received >/= 5 d of total parenteral nutrition (TPN) were compared with 8 ICU patients who had fasted for >/=5 d. Both groups were studied before and after 5 d of enteral nutrition (EN). Each patient served as his or her own control. Duodenal bile was analyzed for biliary lipid content and serum lipids were determined simultaneously. Duodenal bile samples from 18 healthy persons served as controls. RESULTS: Bile salt concentrations in all ICU patients were 17% of control values before EN (P < 0.005) and 34% of control values after 5 d of EN (P < 0.005). Phospholipid concentrations were 12% of control before EN (P < 0. 0005) but increased almost 4-fold after EN (P < 0.0005). Biliary cholesterol concentrations were 20% of control values before EN (P < 0.001) and did not improve afterward. No difference in bile composition was observed between fasted ICU patients and those who received TPN. The inverse correlation between the severity of illness and biliary lipid concentrations observed before EN disappeared with enteric stimulation. The low serum concentrations of HDL cholesterol and apolipoprotein A-I increased significantly with EN in all ICU patients. CONCLUSION: Lack of EN during critical illness was associated with profound decrements in biliary lipid concentrations that normalized partially after 5 d of EN. We hypothesize that loss of enteric stimulation in ICU patients impairs hepatic lipid metabolism.  相似文献   
96.

Background

In the literature there is some evidence that the incidence of metastases may increase after radiation treatment.

Methods

In order to investigate whether radiation-induced changes in the lymphatic drainage may alter the rate of lymph node metastasis, the center part of the left hind foot of rats was irradiated with a dose of 1 x 55 Gy before inoculation of tumor cells into the irradiated part of the footpad at different time intervals. Cells of 2 different tumor lines were employed. A rarely metastasising rhabdomyosarcoma, R-l, to look for a possible enhancement of lymphatic metastases, and a readily metastasising mammary carcinoma, Cl-2, in case of a possible decrease in the rate of lymphatic metastasis from tumors growing in pre-irradiated footpads.

Results

The incidence of regional lymph node metastasis decreased for R-l tumors growing in pre-irradiated footpads, but not for Cl-2 tumors. Furthermore, the average time required for lymph node metastasis to attain a reference volume of 100 mm3 is not significantly influenced by pre-irradiation of the footpad. No difference was observed in average times for doubling in volume of lymph node metastases originating from primary tumors in pre-irradiated footpads. Abscopal effects after footpad irradiation may cause a 50-fold increase in size of regional lymph nodes and, therefore, histological examination is essential for verification of lymph node metastases.

Conclusions

Damage to the lymphatic system to be expected in the irradiated footpad did not enhance the incidence of regional metastasis of R-1 tumors. A reduced rate of lymphatic metastasis contradicts earlier findings of enhanced lymphatic metastasis development of R-l tumors, growing in pre-irradiated gastrocnemius muscles. The influence of irradiation on regional metastasis formation seems to be “tumor bed” dependent for R-l tumors.  相似文献   
97.
In order to determine the effectiveness of high-quality foam replacement mattresses in the treatment of pressure ulcers, one such mattress (TheraRest) was compared with a water mattress (Secutex). One hundred and twenty nursing home patients with pressure ulcers were randomised into two groups and nursed on one of the mattresses for four weeks. After four weeks, 45% of the patients using the foam mattress were completely healed, compared with 48.3% of those using the water mattress. This difference is not significant. Since high-quality foam mattresses are cheaper in the long term than water mattresses, and are easier for nursing staff to manage, it is suggested that these mattresses are preferable.  相似文献   
98.
The pharmacokinetics and tolerability of the novel antiexcitatory agent, riluzole, were compared in 18 healthy elderly and 18 healthy gender- and weight-matched young volunteers. All participants received riluzole 50 mg twice daily (the recommended dosage for patients with amyotrophic lateral sclerosis), administered orally for 5 days. The pharmacokinetics of riluzole, determined on the morning of the 5th day of dosing, were not significantly affected by age or gender. The mean terminal elimination half-life (t1/2), however, was statistically significant between elderly and young subjects. Riluzole was well tolerated upon repeat dose administration. Headache was the most frequent adverse event reported, and there was no overt difference in the type, frequency, or severity of adverse events between elderly and young volunteers or between genders. In conclusion, these results indicate that no dosage adjustments of riluzole are required in the elderly.  相似文献   
99.
100.
The angiographic analogue of the sunburst, (right angle) periosteal new bone formation in osteogenic sarcoma is described. The angiographic findings in this tumor and their relationship to the pathologic appearance are discussed.  相似文献   
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