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1.
Seven middle-aged men with manifest type II diabetes mellitus underwent an endurance training programme for 10–15 weeks. The maximal aerobic capacity, as well as the endurance capacity, was improved by 10% (p<0.05). The intramuscular glycogen store increased by more than 80% (p<0.05) from 350 μmol/g dw (dry weight), and the activities of citrate synthase and 3-hydroxy-acyl-CoA dehydrogenase increased by more than 50% (p<0.05) and 30% (p<0.05). The activity of glycogen synthase was decreased by approximately 20% (p<0.05), whereas lactate dehydrogenase remained unchanged. Capillaries/fibre and fibre area increased by more than 50% (p<0.05) and 30% (p<0.05) leaving the area of supply constant. Training did not influence fasting blood lipids and glucose, glycosylated hemoglobin, oral glucose tolerance, and insulin response to an oral glucose load measured 72 hours post-exercise. It is concluded that patients with manifest type II diabetes, as normoglycaemic individuals, adapt to physical training. However, no persistent effect on glucohomeostasis and lipaemia is produced by short-term training in the diabetic patients. 相似文献
2.
NILS DAHLGREN BENGT NILSSON TAKEFUMI SAKABE BO K. SIESJ
《Acta physiologica (Oxford, England)》1981,111(4):475-485
The effect of the fatty acid cyclo-oxygenase inhibitor indomethacin on cerebral blood flow (CBF) and the metabolic rate for oxygen (CMRO2) was studied in paralyzed and artificially ventilated rats. In normocapnic animals, the drug (10 mg·kg-1i. v.) reduced CBF to 50% of control without a measurable effect on CMRO2. During hypercapnia (PaCO2 70–80 mmHg) the increase in CBF was reduced by about 80% but CMRO2 remained unchanged. Autoradiographic evaluation of local CBF in 20 brain structures indicated that the reduction in CBF was relatively uniform throughout the brain. Dose response curves showed that an effect on CBF was evident already at an indomethacin dose of 1 mg·kg-1 and maximal effects were obtained with 3–5 mg·kg-1. Following i. v. injection of the drug reduction in CBF was observed already after 10 s and the full response occurred after 1–2 min. It is concluded that metabolites of arachidonic acid, possibly mainly prostacyclin, are powerful modulators of normal cerebrovascular tone, and help to mediate the CBF response to increased CO2 tensions. However, since indomethacin does not modify the circulatory response in other conditions with increased CBF these substances do not qualify as general coupling factors controlling CBF in physiological or pathological states. 相似文献
3.
TORE K. USKI KARL-ERIK ANDERSSON LENNART BRANDT BENGT LJUNGGREN 《Acta physiologica (Oxford, England)》1984,121(4):369-378
The contractile and relaxant effects of various prostanoids were studied on isolated human pial arteries. Contractions were elicited with the following order of potency: U46619?U44069>PGB2>PGF2a>PGE2?PGD2>PGF1a≥TXB2, indicating that prostanoid-induced contractions probably are mediated by a thromboxane-sensitive receptor. Relaxation of PGF2a-contracted arteries was induced with the order of potency: PGE2> PGE1>PGD2?PGD1. Vessels contrated by K+ were relaxed only by PGE,. Since PGI2 was previously found to be more potent than all the prostanoids tested in the present study, relaxant responses are probably mediated via a PGI2-sensitive receptor. The roles of free extracellular and cellularly bound calcium for the contractile effects of PGF2a and K+ were estimated by incubating the arteries for various times in calcium-free medium containing 10-5 M EGTA. Incubation for 5–10 min abolished K+-induced contractions, whereas after 40 min of incubation PGF2a still induced contractions that reached 70% of control. The PGF2a-induced contraction was biphasic in 8 out of 10 preparations. The second phase could be eliminated by increasing the EGTA-concentration to 10-4 M, as well as by nifedipine pretreatment. In calcium-free, high K+ medium calcium-induced contractions were elicited at lower concentrations in the presence of PGF2a. The results suggest that PGF2a-induced contractions in human pial arteries are relatively independent of free extracellular calcium. PGF2a may promote trans-membrane influx of calcium, as well as release calcium from seemingly superficially located cellular stores. 相似文献
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BENGT ANDRÉASSON MAGNUS LINDROTH NILS W. SVENNINGSEN BJÖRN DREFELDT GERT-INGE JÖNSSON LISBET NIKLASON BJÖRN JONSON 《Acta paediatrica (Oslo, Norway : 1992)》1989,78(2):194-204
ABSTRACT. A new method has been evaluated for measuring ventilation and lung mechanics in spontaneously breathing infants by means of a face chamber. Airway flow is measured with a pneumotachograph inserted between the face chamber and a stable pressure source. Oesophageal pressure is measured via a water-filled oesophageal catheter. The method is suitable for use in conjunction with continuous positive airway pressure (CPAP) treatment in neonatal intensive care. A flat frequency response curve up to 15 Hz for the two measuring systems (i.e., airway flow and oesophageal pressure), and a time shift between the two respective signals of less than 2 msec are prerequisites for correct evaluation of respiratory mechanics. In preterm infants with chest distortion, the inhomogeneity of pleural pressure affects the significance of resistance and compliance values, as calculated from oesophageal pressure. Supra-diaphragmatic pressure variations reflect the resistive and elastic load on the diaphragm exerted by the lungs and thorax. Thus, oesophageal pressure is still useful in studies of respiratory mechanics in preterm infants. 相似文献
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JOHAN C. H. GENTZ RICHARD WARRNER BENGT E. H. PERSSON MARVIN CORNBLATH 《Acta paediatrica (Oslo, Norway : 1992)》1969,58(5):481-490
Blood glucose, plasma insulin, FFA and β-hydroxybutyrate values during intravenous glucose tolerance were reported in 20 small for gestational age (SGA) and 15 appropriate for gestational age (AGA) low birthweight infants. The babies were divided into three groups according to their age when tested; <24 hours, 24–48 hours and >48 hours. Both the SGA and AGA infants cleared glucose more rapidly with increasing age. The change was more marked in the SGA babies. The clearance rates were similar to those reported in normal full-sized infants. The insulin values before the glucose load were similar in all groups and comparable to those reported in normal newborn infants. The insulin response to glucose was variable. There were no significant differences with increasing age or between the two groups of infants. The insulin curve of the individual infant followed one of three patterns. Most commonly seen was a double-peak curve. The infants who showed a single-peak insulin response had a better but not significantly different glucose tolerance than that of the other babies. Infants with no appreciable insulin response still removed glucose from plasma at a rate similar to those with a double-peak insulin curve. It is concluded that insulin as measured in peripheral plasma could not explain the rate of removal of glucose from the plasma of the newborn low birthweight infant. Infants of low birthweight had higher plasma FFA values as compared to that reported in normal full term infants. The FFA values in SGA infants were higher than those in AGA babies. In both groups of infants, the jS-hydroxybutyrate values were comparable to those reported in normal full-term babies. Thus there was an unexpected discrepancy between the high FFA and relatively low β-hydroxybutyrate levels in plasma. The fall in plasma FFA and β-hydroxybutyrate after glucose was minimal but similar in both groups of infants. The findings are compatible with a decreased sensitivity to insulin in the infants studied. 相似文献
10.
It has been shown that melanin has the properties of a polyanion and may in vivo and in vitro bind inorganic cations and drugs which are positively charged at physiological pH by a cation-exchange mechanism. In the present study, we explored if the organic aliphatic polycation spermidine would bind to melanin in vivo after administration of 14C-spermidine to pigmented mice and in vitro at incubations with pigment from beef-eyes. The results showed a high labelling of the pigmented tissues in the mice after the administration of 14C-spermidine. At long survival intervals, the radioactivity in the melanin was higher than in any other tissue. A strong melanin affinity of 14C-spermidine was found in vitro. An analysis of the binding by the method of Scale hard showed that the data could be best fitted by the assumption of two classes of binding sites. The in vivo bound material could be displaced by in vitro incubation in solutions containing inorganic cation-chloride salts or HCI and HC1 was also very effective in inhibiting the melanin-binding of 14C-spermidine in vitro. The results indicate that an electrostatic interaction between spermidine and melanin will occur both in vivo and in vitro. 相似文献