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91.
We examined a property of emulsion formation of propofol (ICI 35868) to release histamine into circulating plasma in dogs. Plasma histamine was measured with radioimmunoassay before (baseline), and 1, 5 and 10min after the administration of 15mg·kg–1 propofol. There were no significant differences between the plasma histamine levels at 1, 5 and 10min after the administration of propofol and the baseline level. We conclude that the emulsion formation of propofol of 15mg·kg–1 does not release histamine during induction of anesthesia in dogs.(Mitsuhata H, Shimizu R: Plasma histamine levels during induction of anesthesia with propofol in dogs. J Anesth 7: 206–209, 1993) 相似文献
92.
The echocardiographic assessment of left ventricular performance during sevoflurane and halothane anesthesia 总被引:3,自引:0,他引:3
The cardiovascular effects of sevoflurane were studied and compared with those of halothane in 30 healthy patients. The patients were assigned to receive 1MAC sevoflurane (n = 10), 2MAC sevoflurane (n = 10) or 1MAC halothane (n = 10) in N2O 2l·min–1 and O2 4l·min–1. The changes in left ventricular diastolic and systolic dimension (Dd and Ds), fractional shortening (FS), mean velocity of circumferential fiber shortening (mVcf), left ventricular diastolic and systolic volume (Vd and Vs), stroke volume (SV), ejection fraction (EF) and cardiac index (CI) were evaluated by echocardiography. Sevoflurane produced significant dose-dependent decreases in FS, mVcf, EF and SV, but no significant changes in Dd and Vd. Therefore, the decrease in SV was due mainly to the increase in left ventricular residual volume (Vs). One MAC halothane produced a more significant decrease in FS, mVcf, EF and SV, when compared to values obtained at 1MAC sevoflourane (P 0.01). CI was more significantly decreased with 1MAC halothane than with 1MAC and 2MAC sevoflurane (P 0.01). This was brought about by a slight decrease in HR with halothane and a slight increase in HR with sevoflurane, in addition to a smaller decrease in SV with sevoflurane than with halothane. This study suggests that sevoflurane may better preserve cardiac function as a pump in healthy patients, when compared to halothane.(Kasuda H, Akazawa S, Shimizu R.: The echocardiographic assessment of left ventricular performance during sevoflurane and halothane anesthesia. J Anesth 4: 295–302, 1990) 相似文献
93.
Takagaki Masao Oda Yoshifumi Miyatake Shin-Ichi Kikuchi Haruhiko Kobayashi Toru Sakurai Yoshinori Osawa Masami Mori Kenjiro Ono Koji 《Journal of neuro-oncology》1997,35(2):177-185
To plan the optimal BNCT using BSH for glioblastoma patients, the10B concentration in tumor and blood was investigated in 11newly diagnosed glioblastoma patients. All patients received 20 mg BSH/kgbody weight 2.5–16 hrs prior to tumor removal. The quantitativedistribution of 10B was determined by prompt gamma rayspectrometry and/or -track autoradiography. 10Bdistribution in tumors was heterogeneous, ± 25% of scatteringat the microscopic level, and the distribution was also heterogeneous at thetissue level. 10B concentration in blood decreased inbi-exponential decay as a function of the time after the end of theadministration. The T/B ratio showed non-exponential increase with largevariation. The maximum T/B ratio would be around 1. The tumor/normal brain(T/N) ratio of 10B concentration was 11.0 ± 3.2. The10B content in normal brain is originated in vascular10B in parenchyma, since the 10B content innormal brain to blood (N/B ratio) being compatible with the blood content inparenchyma. These values allow for BNCT, using thermal neutrons, on braintumors located less than approximately 3.3 cm in depth from the brainsurface of neutron incidence, providing that the dose on the normalendothelium is controlled to less than the tolerance limit. In ourpreliminary study of BNCT, a 31% 3-year survival was achieved overall for 16 glioblastoma patients and a 50% 2-year survival wasachieved on 8 glioblastoma patients in our recent dose escalation studybased on these data. 相似文献
94.
Social olfactory recognition in rodents has been shown to assess short-term memory and to be sensitive to cholinergic drugs. It is based on the investigation of a juvenile by an adult rat and is measured by a reduction in duration of exploration during the second of two successive exposures lasting 5min. The present experiments further characterize rodent social recognition in pathophysiological models known to impair memory. Social recognition was distrupted by ageing in both rats and mice, by vincristine-induced septal lesion and by damaging the CA1 hippocampal layer after cerebral ischaemia in rats. These memory deficits could be compensated by reducing the time interval between the two presentations of the juvenile and/or by prolonging the juvenile encounter. Similarly, muscarinic agonists (arecoline, SR 46559A) counterbalanced the memory impairment in the three models. The present results indicate that the hippocampus plays a key role in social recognition. They suggest that in the three pathophysiological models, memory ability is still present although it is of very short duration; however, it can still be improved by pharmacological treatments. 相似文献
95.
96.
Dzierzanowska D Lopaciuk U Kamińska W Wieczyńska J Pawińska A Patzer J 《International journal of antimicrobial agents》1995,5(3):179-182
This study examines the antibiotic susceptibility of 1792 bacterial strains isolated from hospitalized children between January and December 1993. A total of 1015 Gram-negative rods represented by members of Enterobacteriaceae family (770) and nonfermenters (245) were isolated. The most resistant strains were noticed among Klebsiella pneumoniae and Enterobacter cloacae. From 38% to 46% of K. pneumoniae strains were resistant to third-generation cephalosporins, but all of them were sensitive to imipenem. From 60% to 80% of E. cloacae isolates were resistant to all beta-lactams, but sensitive to imipenem. Resistance of P. aeruginosa to aminoglycosides varied from 30% for gentamicin to 5% for amikacin. About 40% of P. aeruginosa strains were resistant to carbenicillin, and 25% to azlocillin and piperacillin, but only two strains were resistant to ceftazidime and imipenem. Among Gram-positive cocci the most frequently encountered were coagulase-negative staphylococci, followed by Staphylococcus aureus and Enterococcus faecalis. The methicillin-resistant strains of coagulase-negative staphylococci and S. aureus consisted 74.8% and 34%, respectively. All strains of methicillin-resistant coagulase-negative staphylococci and S. aureus were sensitive to vancomycin. 相似文献
97.
This paper analyses the relationship between the thickness of the anterior femoral head cartilage (FHC), as measured by ultrasound, and some anthropometric parameters, such as height, weight, skeletal and chronological age. In addition, it provides standard norms for FHC thickness in a paediatric population. Both hips were examined in 213 consecutive subjects (99 boys and 114 girls), aged 1.9–14 years. Seventy-four subjects underwent hand and wrist X-rays for skeletal maturation: 32 of these were dropped from the study because a discrepancy as high as two standard deviations was found between their skeletal and their chronological age. The thickness of FHC correlated strongly with skeletal and chronological age, standing height and body weight. A side difference of 0.2 mm in FHC was considered to be abnormal. The study population was divided into 13 groups according to chronological age and values of FHC for boys and girls are provided for each group. It is suggested that the magnitude of hyaline FHC is a valuable feature in the evaluation of skeletal maturation in children. 相似文献
98.
Multinucleated giant cells (MNGCs) are reported in many thyroid lesions. This study examines whether their quantity and quality can help in the differential diagnosis. All fine-needle aspirations (FNAs) of the thyroid with a "significant" number of MNGCs were reviewed from 1995 -1998. There were 23 cases (<1% of thyroid FNAs): 8 papillary carcinomas (PC), 4 subacute thyroiditis (ST), 3 granulomas, 7 adenomatous goiters (AG), and one Hurthle-cell adenoma (HA). MNGCs with dense cytoplasm were seen exclusively in PC, ST, and granulomas. They had angulated shapes. They were most numerous, largest, and with the highest number of nuclei in ST and granulomas. MNGCs with foamy cytoplasm were seen in AG and HA and 80% of the other cases (PC, ST, and granulomas). In PC, rare MNGCs had intranuclear inclusions and grooves. The accompanying cell population was characteristic of each disease. The quantity and quality of MNGCs in thyroid FNA may be helpful in narrowing the differential diagnosis. Diagn. Cytopathol. 1999;21:307-312. 相似文献
99.
The influence of social class, strain and social support on symptoms of anxiety and depression in mothers of toddlers 总被引:3,自引:0,他引:3
Background: The aim of the study was to identify risk and protective factors for anxiety and depression among mothers of toddlers. Methods: A population-based sample of 921 Norwegian mothers with 18-month-old children completed a questionnaire designed to examine
the impact of socioeconomic and demographic factors, somatic health problems, negative life events, chronic strain and social
support on symptoms of anxiety and depression (HSCL-25). Results: There was a moderate aversive effect of negative life events and chronic strain and a moderate protective effect of social
support on the symptom level, but no interaction effects were found between the risk and protective factors. Behaviour problems
among the children clearly seemed to affect the mothers' symptom level. The symptom level varied with background factors like
the mothers' education, employment status and age even after controlling for the effect of strain and social support. The
largest effect of the background factors seemed to be indirect, however, mediated through their effect on the risk and protective
factors. Conclusions: Although problems with the children's behaviour and child care arrangements were observed to have a strong impact on the
mothers' symptom level, the frequencies of such problems appeared to be less dependent on socioeconomic conditions than did
other types of strain.
Accepted: 21 July 1998 相似文献
100.
Alonso R Gnanadicom H Fréchin N Fournier M Le Fur G Soubrié P 《The European journal of neuroscience》1999,11(3):967-974
A remarkable feature of dopamine functioning is that the concomitant activation of D1-like and D2-like receptors acts to intensify the expression of various dopamine-dependent effects, in particular the expression of the immediate-early genes, c-fos and zif268. Using non-peptide neurotensin receptor antagonists, including SR48692, we have determined that blockade of neurotensin receptors reduced the cooperative responses of direct acting D2-like (quinpirole) and partial D1-like (SKF38393) dopamine agonists on the expression of Fos-like antigens and zif268 mRNA. Pretreatment with SR48692 (3 and 10 mg/kg) reduced the number of Fos-like immunoreactive cells produced by the combined administration of SKF38393 (20 mg/kg) and quinpirole (1 mg/kg) in the caudate-putamen, nucleus accumbens, globus pallidus and ventral pallidum. High-affinity neurotensin receptors are likely to be involved in these D1-like/D2-like cooperative responses, as compounds structurally related to SR48692, SR48527 (3 mg/kg) and its (-)antipode, SR49711 (3 mg/kg), exerted a stereospecific antagonism in all selected brain regions. Pretreatment with SR48692 (10 mg/kg) also diminished Fos induction by the indirect dopamine agonist, cocaine (25 mg/kg), particularly at the rostral level of the caudate-putamen. In situ hybridization experiments in the caudate-putamen indicated that SR48692 (10 mg/kg) markedly reduced zif268 mRNA labelling produced by SKF38393 plus quinpirole in cells not expressing enkephalin mRNA, but was unable to affect the concomitant decrease of zif268 mRNA labelling in enkephalin-positive cells. Taken together, the results of the present study indicate that neurotensin is a key element for the occurrence of cooperative responses of D2-like and partial D1-like agonists on immediate-early gene expression. 相似文献