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991.
992.
Aim: To determine the factors affecting the topographic characteristics of the optic nerve head in a normal Turkish population. Methods: A cross‐sectional study was performed on the optic nerve head of the right eyes of 613 healthy subjects of both sexes aged 11?77 years using a confocal scanning laser ophthalmoscope. The study population was divided into three groups (<20 years, 20?50 years, and>50 years) to evaluate age‐related changes in the optic nerve head topography. A total of 15 variables were determined. Statistical analysis was performed using Student's t‐test, anova, Tukey HSD test, linear regression analysis and Pearson's correlation coefficient. Results: Four eyes were excluded from the study due to poor image quality. There were 307 female subjects and 302 male subjects. The mean age of the subjects was 42.1 ± 15.1 years. The mean optic disc areas were 1.99 ± 0.45 mm2 and 1.97 ± 0.41 mm2 for male and female subjects, respectively. The disc area of the subjects ranged between 1.01 and 4.19 mm2. Disc area was found to be associated with all of the optic nerve head variables studied, and was also found to be significantly increased with advancing age (P < 0.05). The only variable that showed a sex‐related difference was neuroretinal rim volume, which was found to be higher in female subjects in all cases. Conclusion: Optic disc area was found to be the main determinant of the optic nerve head topography in a normal population. Optic disc area was found to be significantly increased with ageing in a normal population. These acquired changes to the optic disc could suggest stretching of the scleral ring, which may highlight the role of advancing age on the pathogenesis of glaucomatous optic neuropathy. 相似文献
993.
Effects of progesterone treatment on cocaine responses in male and female cocaine users 总被引:4,自引:0,他引:4
We recently reported that progesterone treatment attenuated some of the subjective effects of smoked cocaine in female cocaine users. In this study, we further examined the interaction between progesterone and cocaine in both male and female cocaine users using subjective, physiological and behavioral outcomes. A total of 10 subjects, 6 male and 4 female cocaine users, had two experimental sessions. Before each session, participants received either two oral doses of 200 mg of progesterone or placebo. Two hours after the second dose of medication treatment, the participants received a 0.3 mg/kg dose of cocaine intravenously and started the self-administration period, in which five optional doses of cocaine were available. Progesterone treatment attenuated the cocaine-induced diastolic blood pressure increases without affecting the systolic blood pressure and heart rate increases. Progesterone treatment also attenuated the subjective ratings of high and feel the effect of last dose in response to cocaine but did not affect cocaine self-administration behavior. These results suggest that progesterone attenuates some of the physiological and subjective effects of cocaine in both male and female participants. The effects of progesterone treatment on cocaine dependence need to be further studied in controlled trials. 相似文献
994.
Nesime Y Lokman B Akif IM Gurol C Basar C Mustafa K 《Veterinary and human toxicology》2004,46(6):342-344
This study determined the spectrum of deaths due to acute agrochemical poisoning in Turkey. Data was obtained from all autopsy reports performed between 1997 and 2001, compiled by the Institute of Forensic Medicine (which is a department of the Ministry of Justice), and evaluated retrospectively. There were 3990 deaths by intoxication of one form or another. Acute agrochemical/pesticide poisoning caused 843 deaths. Almost half were under 30 yo; 55% were female and 45% were male. Of 205 deaths whose manner of death was determined, 153 (75%) were suicide; the most common substance used was insecticide followed by sulfur, rodenticides, and herbicides. The pattern appeared consistent from 1997 to 2001 with no decline in the number of cases, despite the government having taken measures to educate the public and reduce pesticide use by offering alternates to control pests and insects. 相似文献
995.
Effect of sildenafil on anxiety in the plus-maze test in mice 总被引:2,自引:0,他引:2
Several studies have shown a role of nitric oxide/cyclic guanosine monophosphate signaling pathway in the regulation of anxiety. The effects of the phosphodiesterase (PDE) 5 inhibitors on anxiety are not fully understood. The aim of present study was to investigate the possible role of sildenafil, an inhibitor of cyclic GMP-specific phosphodiesterase, on anxiety in the plus-maze test in mice. Sildenafil at a dose of 0.5 mg/kg had no significant effect on the behavior in the plus-maze test but at doses of 1 and 3 mg/kg induced an anxiogenic effect. The combination of sildenafil (1 mg/kg, i.p.) and methylene blue (1 mg/kg, i.p.) abolished the anxiogenic-like effect of sildenafil. The combination of sildenafil (1 mg/kg, i.p.) and L-arginine (50 mg/kg, i.p.) decreased the percentage of time spent in open arms compared to saline-treated group. Diazepam at a dose of 2 mg/kg significantly increased the percentage of time spent in open arms (p < 0.05). Sildenafil at a dose of 3 mg/kg and the combination of L-arginine (50 mg/kg, i.p.) and sildenafil (1 mg/kg, i.p.) significantly decreased the locomotor activity (p < 0.05). These results suggest that a nitric oxide-cGMP pathway seems to play an important role in sildenafil-induced anxiogenic-like effect. 相似文献
996.
997.
998.
Kocak N Ustün H Gülkaç MD Kanli AO Borazan A Yilmaz A 《Acta oncologica (Stockholm, Sweden)》2004,43(2):204-208
The present study was carried out to evaluate the effects of 1alpha,25-dihydroxyvitamin D3 (VD) on chromosomal aberrations induced by doxorubicin (DXR). Wistar rats were divided into eight experimental groups of five animals each. Control group animals were treated with i.p. distilled water. The animals in three VD groups were given only VD for 4, 6 or 8 weeks. In the DXR groups the animals were given only DXR. In the combination groups VD doses were given for 4, 6 or 8 weeks for each group and DXR was injected 24 h before sacrificing the rats. DXR (50 mg/100 g b.w.) was injected intraperitoneally and VD by gavage 3 microg/kg/day twice weekly. Animals treated with both VD and DXR showed a low frequency of chromosomal aberrations and abnormal metaphases when compared with animals treated with DXR alone (p < 0.0001). The numbers of both chromosomal aberrations and abnormal metaphases were similar in weeks 6 and 8 (p > 0.05) and lower than those in week 4 for the VD groups (p < 0.0001). Under the present experimental conditions, the efficiency of VD in protecting cells against DXR-induced chromosome damage was found to be dose dependent. The protective effects of VD on chromosome aberrations induced by DXR are discussed in the light of literature data. 相似文献
999.
1000.
We aimed to investigate whether there is a direct correlation of serum IgE concentration with severity of acute pulmonary thromboembolism (PTE). DESIGN: Prospective study. SETTINGS: University medical center. Forty-six patients (27 female, 19 male) who were diagnosed as acute PTE in our clinic between 01 October 2000 and 30 November 2001 comprised the study group. Mean age was 55 (range was 20-82). The study group was divided into three groups according to severity of PTE: Group A, submassive PTE without pulmonary infarction (20 patients); group B, submassive PTE with pulmonary infarction (15 patients); and group C, massive PTE (11 patients). Serum IgE concentrations were measured by ELISA method at 1st, 5th, 15th, 30th, 60th, 90th days, and 120th days, if needed, after the diagnosis. Statistical analysis was made by Post hoc Tukey test. First day serum IgE levels were highest in group B (mean 507.7) followed by group C (mean 324.2), and were lowest in group A (mean 117.2). The differences between group B and group C, between group B and group A, and also between group C and A were all statistically significant (p< 0.5, p< 0.0001, p< 0.015, respectively). 5th day and 15th day results showed statistically significant differences between group B and A, and between group C and A (at 5th day: p<0.0001, p< 0.015 respectively, and at 15th day: p< 0.0001, p< 0.012 respectively). At 30th, 60th, and 90th days of diagnosis serum IgE concentrations were higher in group B than in group A which were statistically significant (p< 0.0001, p< 0.0001, p< 0.019 respectively). Patients with submassive PTE and pulmonary infarction had the highest serum IgE concentrations and the longest duration of high levels of IgE. 相似文献