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61.

Background

The under-5 mortality rate (U5MR) is an important metric of child health and survival. Country-level estimates of U5MR are readily available, but efforts to estimate U5MR subnationally have been limited, in part, due to spatial misalignment of available data sources (e.g., use of different administrative levels, or as a result of historical boundary changes).

Methods

We analyzed all available complete and summary birth history data in surveys and censuses in six countries (Bangladesh, Cameroon, Chad, Mozambique, Uganda, and Zambia) at the finest geographic level available in each data source. We then developed small area estimation models capable of incorporating spatially misaligned data. These small area estimation models were applied to the birth history data in order to estimate trends in U5MR from 1980 to 2015 at the second administrative level in Cameroon, Chad, Mozambique, Uganda, and Zambia and at the third administrative level in Bangladesh.

Results

We found substantial variation in U5MR in all six countries: there was more than a two-fold difference in U5MR between the area with the highest rate and the area with the lowest rate in every country. All areas in all countries experienced declines in U5MR between 1980 and 2015, but the degree varied both within and between countries. In Cameroon, Chad, Mozambique, and Zambia we found areas with U5MRs in 2015 that were higher than in other parts of the same country in 1980. Comparing subnational U5MR to country-level targets for the Millennium Development Goals (MDG), we find that 12.8% of areas in Bangladesh did not meet the country-level target, although the country as whole did. A minority of areas in Chad, Mozambique, Uganda, and Zambia met the country-level MDG targets while these countries as a whole did not.

Conclusions

Subnational estimates of U5MR reveal significant within-country variation. These estimates could be used for identifying high-need areas and positive deviants, tracking trends in geographic inequalities, and evaluating progress towards international development targets such as the Sustainable Development Goals.
  相似文献   
62.

Background

Sepsis has represented a substantial health care and economic burden worldwide during the previous several decades. Our aim was to analyze the epidemiological trends of hospital admissions, deaths, hospital resource expenditures, and associated costs related to sepsis during the twenty-first century in Spain.

Methods

We performed a retrospective study of all sepsis-related hospitalizations in Spanish public hospitals from 2000 to 2013. Data were obtained from records in the Minimum Basic Data Set. The outcome variables were sepsis, death, length of hospital stay (LOHS), and sepsis-associated costs. The study period was divided into three calendar periods (2000–2004, 2005–2009, and 2010–2013).

Results

Overall, 2,646,445 patients with sepsis were included, 485,685 of whom had died (18.4%). The incidence of sepsis (events per 1000 population) increased from 3.30 (2000–2004) to 4.28 (2005–2009) to 4.45 (2010–2013) (p?<?0.001). The mortality rates from sepsis (deaths per 10,000 population) increased from 6.34 (2000–2004) to 7.88 (2005–2009) to 7.89 (2010–2013) (p?<?0.001). The case fatality rate (CFR) or proportion of patients with sepsis who died decreased from 19.1% (2000–2004) to 18.4% (2005–2009) to 17.9% (2010–2013) (p?<?0.001). The LOHS (days) decreased from 15.9 (2000–2004) to 15.7 (2005–2009) to 14.5 (2010–2013) (p?<?0.001). Total and per patient hospital costs increased from 2000 to 2011, and then decreased by the impact of the economic crisis.

Conclusions

Sepsis has caused an increasing burden in terms of hospital admission, deaths, and costs in the Spanish public health system during the twenty-first century, but the incidence and mortality seemed to stabilize in 2010–2013. Moreover, there was a significant decrease in LOHS in 2010–2013 and a decline in hospital costs after 2011.
  相似文献   
63.
The quality of aquatic environments all around the world is being altered by different human activities that represent direct threat to the ecological system and the aquatic biota. This study aimed to evaluate the occurrence of histological and genotoxic alterations in Prochilodus lacustris as indicators of anthropic impacts in a lacustrine environment in northeast Brazil. The histological alterations were evaluated using the histological alteration index, and the genotoxic alterations were detected using the micronuclei test, at three sampling stations (S1, S2 and S3). The gills presented lesions with three stages of severity, with mild lesions more frequent in the specimens collected at station S1. Mild hepatic tissue lesions were the most frequent type in both areas. Micronucleus analysis showed that station S3 was the most affected. The biological responses observed indicated that the fish are under influence of environmental changes. It is important to highlight that the organisms collected at station S3 had a more compromised health status.  相似文献   
64.
OBJECTIVE: Three-dimensional analysis of palate size and shape in patients with isolated cleft palate at the stage of permanent dentition. DESIGN: Cross-sectional study using Fourier transform profilometry.Subjects: Twenty-nine randomly selected dental casts of approximately 15-year-old boys with isolated cleft palate and 28 dental casts of normal boys of the same age.Interventions: All patients were operated on by the same method (pushback and pharyngeal flap surgery) at a mean age of 4.5 years. MAIN OUTCOME MEASURES: Data on the palate height in 210 defined locations (pixels). RESULTS: The palate in isolated clefts is narrower throughout its whole extent and lower from the level of the first premolars. The difference, as compared with controls, increases in a posterior direction. At the level of the first molars, palatal height is reduced by one-quarter, the area of the transversal section by more than one-third. The shaping of the palate vault is, on average, symmetrical with a marked interindividual variability. Palatal height does not depend on the width of the dentoalveolar arch, and the height of the primary palate is not reduced. CONCLUSION: The smaller width and reduced height from the level of the first premolars posteriorly confirm the substantially reduced space available for the tongue in patients with isolated cleft palate. Deviations are on the average symmetrical, and the anterior part of the palate is not shallower.  相似文献   
65.
Durable clenching on a particular occlusal area may affect the masticatory muscle activity and induce transitional deformation of the dentoalveolar, mandibular and temporomandibular tissues. These effects may provide detectable alterations in the occlusal contact pattern. The aim of this study was to evaluate the subsequent effect of clenching on the number and location of occlusal contacts. This study was carried out on 16 volunteers with correct occlusion and sharply demarcated occlusal contact pattern. The patient closed to intercuspal position with maximal biting force and the occlusal contacts were revealed with a 12 microns thick occlusal foil. Then a gnathometer was placed between the upper and lower incisors and the mouth was closed for two minutes with about 50 N closing force. After that the occlusal contacts were evaluated again. Paired t-test was used to evaluate the data. Both before and after clenching the highest average number of contacts was recorded on the surface of first molars. They were followed in decreasing order by the second molars, second premolars, first premolars, and finally the canines. When the number of contacts was compared in tooth groups, the first molars and the second premolars had more contacts than the second molars and the first premolars. On the surfaces of molars more occlusal contacts were registered after clenching than before. Significant differences were found in case of the left second molar only. It was concluded that durable clenching on a particular occlusal area might change transitionally the distribution of occlusal contacts.  相似文献   
66.
Conditioning agents used on dentin with composite materials are biologically active and may have deleterious effects on the pulpal microcirculation. No data are available on the immediate vascular effect of etching materials applied on a constant thin pulpal dentin. In this study the authors examined whether the application of 36% phosphoric acid (Conditioner 36, 15 seconds) or itakonic acid with 10% maleic acid (NRC Non-Rinse Conditioner, 20 seconds), as recommended by the manufacturers, alters the blood circulation in the pulp of the rat's lower incisors. The effect of prolonged etching time (60 seconds) was also assessed (Conditioner 36). The application of saline served as the untreated control. The technique of vitalmicroscopy was used on the first lower incisor of 40 (10-10 in each group) male Sprague-Dawley rats (weighing 350 +/- 8 g SE) to record the changes in vessel diameter prior to and at 5, 15, 30 and 60 minutes after the test materials were administered on the dentin. In the control rats, the vessel diameter was stable during the entire experiment. Acid conditioning as recommended by the manufacturers tended to cause vasodilatation, though these alterations were statistically not significant when compared to the control group (ANOVA, p > 0.05). After prolonged etching time (Conditioner 36, 60 seconds) significant vasoconstriction (-14.4 +/- 6.13; -10.59 +/- 4.2; -11.96 +/- 6.75; -5.49 +/- 5.78%) was observed (ANOVA, p < 0.05). In this group, stasis developed in pulpal blood circulation in 40% of rats (Cochran's-Q test, p < 0.05), gas-bubble formation was observed in 30% and the disappearance of the pulpal wall occurred in 20%. These results suggest that exposition time with acid is crucial to the pulpal microcirculation. That is, acid conditioning applied as indicated (for 15-20 seconds) onto a very thin layer of dentin only slightly affects the blood supply to the dental pulp; however, prolonged etching time (for 60 seconds) results in immediate failure of microcirculation in the dental pulp of rats.  相似文献   
67.
The presence of foreign biological substances in the human body can lead to violent immune reactions. This is the report of a very rare case involving not only the presence of a biological substance, but also a symbiotic relationship between a living plant (the common wheat grain, Triticum aestivum L.) and the human body. Black coal particles and one cereal grain were removed from the subgalea of the right parietal region of a 35-year-old man who had sustained injuries in a motor vehicle accident 16 days earlier. There were signs of germination of the grain, but no macroscopic or microscopic evidence of an inflammatory reaction. Grain germination was verified microscopically. There are various explanations for the absence of an immune reaction, but only coal-tar-induced immunosuppression can explain the observed phenomenon.  相似文献   
68.
The salivary excretion of cefoxitin (Mefoxin), a second-generation beta-lactam antibiotic of the cefalosporin group, which shows enhanced anti-anaerobic effect was investigated in oral surgery patients. In animal experiments the saliva levels of imipenem (Tienam) and meropenem (Meronem), which also belong to the betalactam carbapenem group were studied. The antibiotics were administered parenterally in single therapeutic doses, then blood samples were taken first after half an hour then hourly, and mixed saliva was collected for 6 hours. Cefoxitin was found to reach top level in the 1st hour, then this level decreased rapidly, and in the 4th hour it was no longer measurable. Out of the carbapenems imipenem showed highest level in the 2nd hour and in the 4th hour its concentration in the saliva was minimal. Meropenem reached a higher level in the saliva (1,5-2 times higher than the serum level) in the 2nd hour after administration, which persisted even in the 6th hour. The experimental results justify the administration of these antibiotics in dentistry and oral surgery.  相似文献   
69.
OBJECTIVE: To evaluate the effects of Streptococcus mutans biofilm/restorative materials interaction on surface roughness, hardness and morphology of materials tested. METHODS: Empress 2 (E2), Filtek Supreme (FS), Vitremer (V) and Ketac Molar Easymix (KM) were tested. Twenty-five disks of each material were made and divided into three storage groups: (1) 100% relative humidity (n=5); (2) growth medium (BHI and 1% sucrose) (n=5); (3) S. mutans biofilm-growth medium (n=15). Before storage, hardness measurements were immediately obtained from group 1 specimens. After 30 days of storage, the specimens were cleaned in order to obtain the surface roughness and hardness values, besides morphology analysis by scanning electron microscopy. RESULTS: The surface roughness and hardness values obtained from E2 and FS specimens did not present statistically significant differences among the groups 1, 2 and 3 and between immediate and 30-day-old specimens of each material. However, group 3 specimens of V and KM showed statistically significant higher surface roughness means than other groups. Group 1 specimens of V and KM also showed higher hardness values than the immediate values. Group 3 specimens of V presented decreased hardness values compared with other groups. The scanning electron micrographs showed an increase in surface degradation from group 1 to group 3 for FS, V and KM. CONCLUSIONS: Thirty-day-old biofilm promotes a negative effect on the surface morphology of FS, V and KM, on the surface roughness of V and KM and on the hardness of V.  相似文献   
70.
OBJECTIVES: This study evaluated the effect of a warm or cold air-dry stream for solvent evaporation on the microtensile resin-dentin bond strength (muTBS), nanoleakage pattern (SEM), degree of conversion (DC) and solvent evaporation rates (SE) of an ethanol/water- (Adper Single Bond, [SB] 3MESPE) and an acetone-based (Prime & Bond 2.1, [PB] Dentsply), two-step etch-and-rinse adhesive system. MATERIALS AND METHODS: Adhesives were applied on demineralized dentin surfaces. For SE, a warm or cold air-dry stream (10 s) was applied prior to light-activation (10 s). Bonded sticks (0.8mm2) were tested in tension (0.5 mm/min). Two bonded sticks from each tooth were immersed in a 50% (w/v) solution of silver nitrate (24 h), photodeveloped (8 h) and analyzed by SEM. The DC and solvent evaporation rate of the adhesives were evaluated under FTIR and analytical balance, respectively. Data were analyzed by two-way ANOVA and Tukey test (alpha=0.05). RESULTS: Higher muTBS and lower nanoleakage were observed when the SE step was performed with warm air-dry stream. However, the DC of the adhesives was not altered by the use of a warm air-dry. CONCLUSIONS: The use of a warm air-dry stream seems to be a clinical tool to improve the bond strength and the quality of the hybrid layer (less nanoleakage infiltration), since it might reduce the number of pores within the adhesive layer.  相似文献   
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