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31.
In the anesthetic management of five patients undergoing excision of pheochromocytoma, adenosine triphosphate (ATP) was used for the purpose of regulating systemic arterial pressure during the period of tumor manipulation. ATP was administered at doses of 0.05–0.4mg/kg/min. Systemic arterial pressure showed a significant decrease from 162 ± 17/103 ± 11mmHg before manipulation to 136 ± 21/81 ± 10mmHg during the manipulation period. The plasma catecholamine levels showed significant increases in this period. Immediately after excision, the systemic arterial pressure was maintained at normal levels (118 ± 13/75 ± 16mmHg) by fluid replacement and discontinuation of ATP administration, subsequently becoming 129 ± 19/79 ± 16mmHg. The heart rate was very stable and tachycardia did not ocurr during the manipulation period. Only one arrhythmic episode ocurred in one patient. The systemic vascular resistance index was significantly lower during the manipulation period than before it. It was therefore considered that ATP was useful as an agent for controlling arterial pressue during the anesthesia for pheochromocytoma.(Murata K, Sodeyama O, Ikeda K et al.: Prevention of hypertensive crisis with ATP during anesthesia for pheochromocytoma. J Anesth 1: 162–167, 1987) 相似文献
32.
Postanesthetic respiratory depression in humans: A comparison of sevoflurane,isoflurane and halothane 总被引:1,自引:0,他引:1
The postanesthetic respiratory depression with sevoflurane, isoflurane and halothane was studied in twenty-one patients. They were divided into three groups of seven patients each. One group underwent sevoflurane anesthesia, another group isoflurane and the third group halothane. Following extubation, the decrease in blood concentration of the anesthetic agent was most rapid with sevoflurane and slowest with halothane. Twenty minutes following extubation, resting ventilation and ventilatory response to carbon dioxide returned to the preanesthetic state with sevoflurane and isoflurane anesthesia. With halothane anesthesia, however, the depressive respiratory effects of halothane remained; depressed ventilatory response to carbon dioxide, decreased tidal volume and increased respiratory frequency. Although halothane has been reported to have the least depressive respiratory effect of the three, its elimination was slowest. Thus the respiratory effects of halothane persisted up to and past the twenty minute mark, far longer than with sevoflurane or isoflurane.(Doi M, Ideda K: Postanesthetic respiratory depression in humans: A comparison of sevoflurane, isoflurane and halothane. J Anesth 1: 137–142, 1987) 相似文献
33.
Eleven male volunteers were studied to compare the airway irritation produced by the four anaesthetic agents: halothane, enflurane,
isoflurane and sevoflurane at two concentrations, equivalent to one and two MAC. Tidal volume, respiratory frequency and functional
residual capacity changes induced by 15 sec inhalation of the anaesthetics were measured using respiratory inductive plethysmograph.
Appearance of the cough reflex was also observed. The order of subjective airway irritation was evaluated by the volunteers.
Inhalation of the anaesthetic agents induced a decrease in tidal volume, increase in respiratory frequency and decrease in
functional residual capacity. Significant changes were considered to have occurred if tidal volume and respiratory frequency
changed by more than 30% from the resting values for at least ten seconds, or if functional residual capacity changed by more
than 30% of the value at resting tidal volume, for at least ten seconds. Each change was induced most frequently by isoflurane
followed by enflurane, halothane and, least frequently, by sevoflurane. The orders of appearance of the cough reflex and of
subjective airway irritation were similar. Sevoflurane did not elicit a cough reflex. It is concluded that sevoflurane was
the least irritant anaesthetic and is considered to be the most suitable for inhalational induction of anaesthesia.
Sept volontaires du sexe masculin font partie dune étude visant à comparer les ejfets irritants de quatre agents anesthésiques
sur les voies respiratoires: l’halothane, l’enflurane, l’ isoflurane et le sévoflurane, à deux concentration qui équivalent
soit à MAC 1, soit à MAC 2. On mesure les changements de volume courant, de fréquence respiratoire et de capacité résiduelle
fonctionnelle à l’aide d’un pléthysmographie à induction. On note l’apparition du réflexe de toux. De plus, on évalue le degré
subjectif d’irritation éprouvé par les sujets. L’inhalation d’agents anesthésiques cause une baisse du volume courant, une
augmentation de la fréquence respiratoire et une diminution de la capacité résiduelle fonctionnelle. On considère significatifs
les changements de volume courant et de fréquence respiratoire de plus de 30% des valeurs de repos pour au moins dix secondes,
les changements de capacité résiduelle fonctionnelle de plus de 30% de sa valeur au volume courant de repos pour au moins
dix secondes. Les changements sont initiés principalement par l’isoflurane, suivi par l’enflurane, l’halothane et moins fréquemment
par le sévoflurane. L’ordre d’apparition du réflexe de toux et de l’impression subjective d’irritation des voies aériennes
est identique. Le sévoflurane ne provoque pas de réflexe de toux. On conclut que le sévoflurane est le moins irritant des
anesthesiques et qu’on peut le considerer comme celui qui convient le mieux à l’induction de l’anesthésie par inhalation. 相似文献
34.
This study was conducted to assess the effect of sevoflurane on lung resistance and compliance, and its responsiveness to
histamine. We studied eight dogs to compare the effect of sevoflurane, isoflurane, enflurane, and halothane on bronchoconstriction
caused by histamine. Baseline values of pulmonary resistance (RL) and dynamic pulmonary compliance (Cdyn) were measured prior to administration of histamine. Histamine (2, 4, and 8 μg · kg−1) were administered iv, and the values of RL and Cdyn at the time of peak effect were recorded. Under 1 or 2 MAC anaesthesia, sevoflurane as well as the other three anaesthetics
had no bronchoactive effects. The four anaesthetics, including sevoflurane, demonstrated inhibitory effect on increases in
RL and decreases in Cdyn caused by histamine. At 1 MAC anaesthesia, % changes in RL caused by 2, 4, or 8 μg · kg−1 of histamine were 38 ± 11, 85 ± 21, or 132 ± 24% (mean ± SE) for halothane, and 65 ± 11, 132 ± 15, or 172 ± 19% for sevoflurane,
respectively. Sevoflurane was less effective than halothane in preventing increases in RL. In preventing decreases in Cdyn, sevoflurane was less effective than halothane only at 8 μg · kg−1 of histamine under 1 and 2 MAC anaesthesia. There was no difference in attenuating effect on changes in RL and Cdyn between sevoflurane and isoflurane or enflurane. We concluded that sevoflurane was less potent than halothane in attenuating
changes in RL and Cdyn in response to iv histamine.
Cette étude a été réalisée dans le but d’évaluer les effets du sévoflurane sur la résistance et la compliance pulmonaires
en réponse à l’histamine. Les effets du sévoflurane, de l’isoflurane, de l’enflurane et de l’halothane sur la bronchoconstriction
induite par l’histamine sont comparés sur huit chiens. Avant l’administration d’histamine, on mesure les valeurs initiales
de la résistance (RL) et de la compliance dynamique (Cdyn) pulmonaires. L’histamine (2, 4, 8 μg · kg−1) est administrée par la voie veineuse et les valeurs maximales de la RL et de la Cdyn sont enregistrées. Les quatre anesthésiques, dont le sévoflurane inhibent l’augmentation de la RL et la diminution de la Cdyn provoquées par l’histamine. A MAC 1 d’anesthésie, les pourcentages de changement de RL produits par 2, 4, ou 8 μg · kg−1 d’histamine sont respectivement de 38 ± 11, 85 ± 21, ou 132 ± 24% (moyenne + SD) pour l’halothane, et de 65 ± 11, 132 ± 15,
ou 172 ± 19% pour le sévoflurane. Le sévoflurane est moins efficace que l’halothane pour prévenir les augmentations de RL. Le sévoflurane est moins efficace pour prevenir la diminution de Cdyn mais seulement à 8 μg · kg−1 d’histamine sous anesthésie à MAC 1 et 2. Le sévoflurane, l’halothane et l’isoflurane ne sont pas de différents pour amortir
les changements de RL et Cdyn. Nous concluons que le sévoflurane est moins puissant que l’halothane pour diminuer la réponse à l’histamine de la RL et de la Cdyn. 相似文献
35.
Terashima Keisuke Takai Satomi Usami Yoshiko Adachi Tetsuo Sugiyama Tadashi Katagiri Yoshihiro Hirano Kazuyuki 《Pharmaceutical research》1996,13(9):1327-1330
Purpose. Indomethacin is well known to be metabolized via O-demethylation and N-deacylation. In this paper we found an enzyme involved in the hydrolysis of amide-linkage of indomethacin and partially characterized it as well as its substrate specificity.
Methods. An indomethacin hydrolyzing enzyme was purified to homogeneity from pig liver microsomes using columns of Q-Sepharose, Red-Sepharose and Blue-Sepharose. The enzyme activity was assayed by measuring of -chlorobenzoic acid liberated from indomethacin by HPLC.
Results. The purified enzyme effectively hydrolyzed the amide linkage in indomethacin but not those in -naphthylacetate and -nitrophenylacetate, which are typical substrates for carboxylesterase. The subunit molecular mass of the enzyme was 65 kDa according SDS-polyacrylamide gel electrophoresis. The Michaelis constant (Km) and maximum velocity (Vmax) values for indomethacin were 67.8 µM and 9.02 nmol/min/mg protein, respectively. The amino acid sequence analysis of the enzyme after cyanogen bromide cleavage showed high homology with a mouse carboxylesterase isozyme designated as ES-male. The activity of indomethacin hydrolysis was relatively high in the pig, rabbit and human liver homogenate, but not in those from rat and mouse. On the other hand, purified human liver carboxylesterases pl 5.3 and 4.5, and pig liver carboxylesterases have no catalytic activity for indomethacin.
Conclusions. These results indicate that the hydrolysis of amide-linkage of indomethacin in humans would be associated with an enzyme similar to the indomethacin hydrolyzing enzyme from pig liver microsomes described here. 相似文献
36.
Key words cardiac arrhythmias - oxygen uptake - carbon dioxide elimination 相似文献
37.
There has been no study comparing the advantage and disadvantage of various antihypertensive agents during surgery for pheochromocytomas because the study is difficult in clinical setting. In the present experiments using dogs, after increasing the arterial blood pressure with norepinephrine, we decreased it to the baseline with sodium nitroprusside (SNP), adenosine triphosphate (ATP), or phentolamine (PE) and compared the hemodynamic changes. A hyperdynamic state was found with ATP and with PE, but not with SNP. The norepinephrine-induced pulmonary hypertension could be successfully treated with SNP, but not with ATP or PE. The reason for these differences are thought to be the different vasodilative properties on peripheral arteries and veins. We conclude that agents that dilates the arteries and veins should be used to regulate the arterial pressure during surgical removal of a pheochromocytoma.(Murata K, Takahashi H, Ikeda K: Comparative cardiovascular effects of SNP, ATP and phentolamine during norepinephrine-induced hypertension in dogs. J Anesth 5: 396–403, 1991) 相似文献
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Chemotherapyremainsoneofthemosteffectivetreatmentsfordisseminatedneoplasia[1 ] .However,theef ficacyofmanychemotherapeuticagentsislimitedbytheirtoxicitytonormaltissues,resultinginanarrowtherapeuticindex.Myelosuppressionisthemostfrequentacutedose limitingsideeffectresponsiblefordelaysindrugadminis trationordoseattenuationwithdecreasedantitumorre sponse[2 4] .Particularly,thrombocytopeniaremainsasig nificantcauseofmorbidityincancerpatientsundergoingallogenicorautologousbonemarrow/bloodstemcellt… 相似文献