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101.
H. W. Van Landuyt J. -M. Fossépré B. Gordts 《European journal of clinical microbiology & infectious diseases》1987,6(2):201-203
A blood-free medium for the recovery of thermophilic
Campylobacter
was compared with Butzler Medium Virion during a one-year study using 2,893 human feces samples. Ninety
Campylobacter
strains (3.1 %) were isolated after incubation for 48 h at 42 C in a candle jar atmosphere. Three strains of
Campylobacter jejuni
were isolated on the blood-free medium only and one on Butzler Medium Virion only. Fecal flora was equally well inhibited on both media except for gram-positive organisms, which were completely inhibited only on the blood-free medium. 相似文献
102.
A new algorithm for QRS delineation has been developed. Based on the envelope of the e.c.g. signal a delineation function
is defined, which yields a single positive pulse for each complex. From this function the onset and end of the QRS or, alternatively,
a fiducial point is determined. To remove low-frequency component such as S-T abnormalities without distortion of the QRS
complex, a filter with time-varying characteristics is used. The accuracy of the method has been evaluated in a test set of
different QRS complexes obtained from coronary care patients. For QRS onset, the standard deviation of the difference between
automated and manual determination was 7 ms in normal beats and 14 ms in ectopic beats. With simulated noise added to each
waveform an average dispersion of 7 ms was observed in the recognition of the QRS onset at a signal-to-noise ratio of 15 dB.
The corresponding dispersion in the location of a fiducial point was 2 ms. Using simulated e.c.g. data, the stability of the
method is demonstrated for transitions between different waveform morphologies.
Presented in part at ‘Computers in cardiology’, Florence, 23rd–25th September 1981 相似文献
103.
104.
Tilki HE Mutluer N Selçuki D Stålberg E 《Electromyography and clinical neurophysiology》2003,43(4):231-234
Herpes zoster (HZ) is essentially a viral disease of the posterior root ganglia and sensory nerve fibers, which presents clinically with vesicular eruption of the skin, radicular pain and sensory changes in the distribution of the affected ganglion. However, motor involvement can be seen as well. If classic cutaneous lesions are present, HZ-related motor paresis is easily diagnosed. Otherwise, the diagnosis may be suspicious, especially if the weakness occurs before the cutaneous lesions have appeared, or weeks after they have subsided. We present a patient with HZ-related motor paresis due to radiculopathy in the cervical segments whose motor symptoms and signs appear as major clinical features. 相似文献
105.
Peter Lindberg Tjelvar Odsjö Lars Reutergårdh 《Archives of environmental contamination and toxicology》1985,14(2):203-212
The levels of polychlorobiphenyls (PCBs), DDT, and total mercury were analyzed in samples of common prey species of the peregrine falcon in two falcon territories, one in northern and one in southern Sweden. Resident and herbivorous prey species showed low residue levels, while elevated levels were found in birds feeding on animals in aquatic habitats. According to biomass, waders accounted for most of the mercury and DDT in the diet of the northern falcons, while the blackheaded gulls had this role in southern Sweden.During the breeding season, the peregrines in northern Sweden were exposed to significantly higher levels of DDT and Hg than the southern peregrines. The estimated average residue levels (based on breast muscles) in the diet were in northern Sweden 0.26 ppm DDT, 0.47 ppm PCB and 0.20 ppm Hg wet-weight. Corresponding figures for southern Sweden were 0.17 ppm DDT, 0.53 ppm PCB and 0.07 ppm Hg.The organochlorine levels in a sample of peregrine eggs were higher than expected from contaminant levels in the diet. It is possible that the main accumulation of pesticides occurs on wintering grounds in western Europe for the Fennoscandian peregrines. 相似文献
106.
The effects of ECT on 5-hydroxyindoleacetic acid, homovanillic acid (HVA), and 4-hydroxy-3-methoxyphenylglycol in cerebrospinal fluid and on kinetic parameters of platelet serotonin uptake were studied in 12 patients with melancholia. There were no significant changes in the monoamine metabolites 3 weeks after initiation of ECT in 12 patients; however, there was a tendency for HVA to increase. The V(max) of serotonin uptake (measured in seven patients) remained unchanged after ECT, but there was a significant increase in K(m), indicating a decreased affinity for serotonin in the carrier. 相似文献
107.
Sophie D. Fosså Asbjørn Flokkmann Mona Heier Magne Aas Brit Moe R. Heintz Sheila Linder-Ciccolunghi 《Cancer chemotherapy and pharmacology》1986,18(3):252-256
Summary Eighteen patients with advanced solid cancer were treated with daily 5-dFUrd infusions given over 1 h on days 1–5 of a 4-week cycle. Nine patients received 3 g/m2 5-dFUrd daily and another nine patients 5 g/m2. One patient on 5 g/m2 5-dFUrd was not fully evaluable for tolerability due to early death (progressive disease) 4 weeks after the first cycle. A total of 48 cycles was given. The gastrointestinal and hematological toxicity was generally mild (grade 1–2). Central neurotoxicity (ataxia, unsteadiness, diplopia, dysarthria, sometimes confusion) was observed in 7 of 8 patients on 5 g/m2 5-dFUrd leading to premature discontinuation of treatment in 3 patients (after 2 cycles). Only 3 of the 9 patients in the 3 g/m2 group had slight signs of cerebellopathy. Typically, the reversible neurological side effects started at the end of the 2nd week of a cycle. The serum elimination kinetics of 5-dEUrd and its metabolites 5-FU and 5-dFUH2 have been investigated in the serum and showed very low intra- and interindividual variations. Peak concentrations of the 5-dFUrd at the end of the infusion approximated 500 mol/l and 1000 mol/l for the 3 g/m2 and 5 g/m2 group, respectively. The peak of the serum 5-FU was reached at the same time, the ratio 5-FU/5-dFUrd being around 10%. The elimination half-life time for 5-FU was protracted by a factor of 2–3 compared with the direct injection of 5-FU.Monthly infusion of 5-dFUrd 5 mg/m2 per day on days 1–5 lead to an unacceptable frequency and degree of neurological toxicity. Similar infusions of 5-dFUrd 3 g/m2 per day on days 1–5 were well tolerated. 相似文献
108.
The present study was undertaken to investigate whether there is an augmented uptake of free fatty acids (FFA) in the leg tissues immediately after surgery when the energy expenditure of the leg is increased considerably. Eight patients were studied before and after cholecystectomy. Blood and plasma flow were determined in one leg, as well as arterio-venous concentration differences for oxygen, glycose, lactate and the total fraction of FFA. To determine uptake and release of FFA, 1-(14C)-oleic acid was infused intravenously and the arterio-venous differences for (14C)-FFA were determined. The mean oxygen uptake in the leg increased from 0.72+/-0.06 mmol/min to 1.78+/-0.41 mmol/min. The uptake of free fatty acids in the leg did not increase significantly after cholecystectomy when compared to before operation in spite of the marked increase in oxygen uptake. Postoperatively there was, however, a positive linear relationship between the uptake of FFA and that of oxygen in the leg. The glucose uptake, after correction for released lactate, corresponded to 7% of the oxygen uptake before surgery and 13% after surgery. The arterial FFA concentration did not change. This study indicates that the combined possible contribution of glucose and free fatty acids to the oxidative energy metabolism of the leg tissues exceeded the oxygen uptake before, but not after surgery. In the postoperative state there was a positive correlation between oxygen uptake and FFA uptake in the leg. 相似文献
109.
Summary The plasma protein binding of amitriptyline, imipramine, clomipramine, and their primary demethylated metabolites were studied by means of a method combining dialysis and gas chromatography. Equilibrium in dialysis of serum containing amitriptyline and its metabolite nortriptyline was attained in about 0.5 h with the drug dissolved in the serum compartment, and in about 2 h with the drug passing from the buffer to the serum compartment.The calculation of free fractions was influenced by variations with dialysis time in the volumes of serum and buffer. Increase of pH in serum increased the protein binding of the weakly basic drugs studied, and made the Donnan distribution effects more pronounced. At pH 7.4, the Donnan effect was negligible.Binding parameters for the 6 tricyclic antidepressant substances studied were estimated for the binding to 1-acid glycoprotein and for total binding in serum. For 1-acid glycoprotein, the k-values ranged from 1·105 to 8·105 M–1, and for pooled serum from 0.4·105 to 8·105 M–1. The determined number of binding sites on the 1-acid glycoprotein was, on average 0.87 for the 6 substances. In serum, the binding capacity was 2–14 times the concentration of 1-acid glycoprotein. 相似文献
110.
M. Larsson S. Landahl P. Lundborg C. G. Regårdh 《European journal of clinical pharmacology》1984,27(2):217-222
Summary The effect of long-term treatment on the absorption and dispsoition of metoprolol has been evaluated in 8 healthy, non-smoking, elderly individuals (mean age 74.5 years) and in a control group of 8 healthy, young individuals. Two trace doses of [3H]metoprolol were given i.v., first concomitantly with a single oral 50 mg dose of cold metoprolol, and second, with the morning dose after 2 weeks of treatment with 50 mg b.d. In the elderly, the mean AUC increased by about 45% (p<0.05) over the treatment period, while in the control group the mean AUC was 18% greater (p<0.05) on Day 14 than on Day 1. In the elderly, changes both in pre-systemic elimination and in total body clearance accounted for the elevation of the AUC, whereas reduced first-pass effect appeared to be the major cause of the increased steady-state plasma level in the control group. With the exception of the volume term, V
, the pharmacokinetic parameters were not significantly different between the elderly and the young individuals. For this reason, almost identical steady-state plasma levels were attained in the two groups. The results suggest that age-related physiological changes may have some minor effects on the pharmacokinetics of metoprolol, and also that the changes do not lead to significantly altered plasma concentrations compared to those in young individuals. 相似文献