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61.
62.
Sonoclot analysis is a point of care test to monitor the coagulation process, presenting a comprehensive evaluation of the clot formation and retraction as well as platelet function. This randomized double-blinded study was designed to investigate the utility of Sonoclot analysis in monitoring the coagulation profile as also the antifibrinolytic effects of tranexamic acid administered in patients with tetralogy of Fallot undergoing intracardiac repair. Eighty of a total 94 patients were randomly divided into two groups of 40 each. In the study group, TA was administered thrice at a dosage of 10 mg/kg, i.e. before CPB, on CPB and after CPB, whereas in the control group, placebo was administered at the same time intervals. Sonoclot analysis and D-dimer measurement were performed at baseline and following heparin neutralisation. An additional variable, DR?? (diminishing rate of clot strength at 15 min postmaximal clot strength), was calculated from the Sonoclot graph and was compared with d-dimer levels as a measure of fibrinolysis. The three Sonoclot variables, i.e. activated clotting time, clot rate and platelet function, were deranged at baseline in all the patients. Post-CPB, the change in these variables was not significant. ACT, clot rate and platelet function showed no significant (P > 0.05) difference in both the groups at both the time intervals. DR?? and d-dimer values were comparable at baseline in both the groups. However, a significant (P < 0.05) difference was seen in these variables in the control group as compared with the TA group following heparin neutralisation. To conclude, Sonoclot analysis is a useful, point of care method for the monitoring of coagulation and fibrinolysis in patients with tetralogy of Fallot undergoing intracardiac repair.  相似文献   
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Rapid auditory processing and auditory change detection abilities are crucial aspects of speech and language development, particularly in the first year of life. Animal models and adult studies suggest that oscillatory synchrony, and in particular low-frequency oscillations play key roles in this process. We hypothesize that infant perception of rapid pitch and timing changes is mediated, at least in part, by oscillatory mechanisms. Using event-related potentials (ERPs), source localization and time-frequency analysis of event-related oscillations (EROs), we examined the neural substrates of rapid auditory processing in 4-month-olds. During a standard oddball paradigm, infants listened to tone pairs with invariant standard (STD, 800–800 Hz) and variant deviant (DEV, 800–1200 Hz) pitch. STD and DEV tone pairs were first presented in a block with a short inter-stimulus interval (ISI) (Rapid Rate: 70 ms ISI), followed by a block of stimuli with a longer ISI (Control Rate: 300 ms ISI). Results showed greater ERP peak amplitude in response to the DEV tone in both conditions and later and larger peaks during Rapid Rate presentation, compared to the Control condition. Sources of neural activity, localized to right and left auditory regions, showed larger and faster activation in the right hemisphere for both rate conditions. Time-frequency analysis of the source activity revealed clusters of theta band enhancement to the DEV tone in right auditory cortex for both conditions. Left auditory activity was enhanced only during Rapid Rate presentation. These data suggest that local low-frequency oscillatory synchrony underlies rapid processing and can robustly index auditory perception in young infants. Furthermore, left hemisphere recruitment during rapid frequency change discrimination suggests a difference in the spectral and temporal resolution of right and left hemispheres at a very young age.  相似文献   
66.
ObjectiveThe association between access to CT facilities for lung cancer screening and population characteristics is understudied. We aimed to determine the relationship between census tract–level socioeconomic characteristics (SEC) and driving distance to an ACR-accredited CT facility.MethodsCensus tract–level SEC were determined from the US Census Bureau. Distance to nearest ACR-accredited CT facility was derived at the census tract level. Census tract–level multivariable regression modeling was used to determine the relationship between driving distance to a CT facility and census tract SEC, including population density (a marker of rural versus urban), gender, race, insurance status or type, and education level.ResultsIn an adjusted multivariable model, census tract–level population density was the greatest relative determinant of distance to a CT facility. Namely, rural census tracts had relatively longer distances to CT facilities than urban census tracts (P < .001). Census tracts with higher uninsured, Medicaid, undereducated (less <high school degree) populations had relatively greater distances to CT facilities (p<0.001), whereas those with higher non-White, female, and Medicare populations had shorter distances (p<0.001).DiscussionRural populations have relatively less geographic access to CT facilities. Furthermore, other vulnerable populations, such as the uninsured, those on Medicaid, and the undereducated, may also have relatively less access to CT imaging facilities. These variations in access to CT may affect the uptake and utilization of lung cancer screening.  相似文献   
67.

Purpose

Studies comparing laparoscopic (LIHR) vs. open inguinal hernia repair (OIHR) have shown similar recurrence rates but have disagreed on perioperative outcomes and costs. The aim of this study is to compare laparoscopic vs. open outcomes and costs.

Methods

The National Surgical Quality Improvement Program (NSQIP) was used to compare durations of surgery, anesthesia time, and length of stay (LOS). The University HealthSystem Consortium (UHC) was used to review the cost and complications between approaches. Patients were matched on demographics, year of procedure and surgical approach between datasets for statistical analysis.

Results

A sample of 5468 patients undergoing OIHR (N = 4,693) or LIHR (N = 775) was selected from UHC from 2008–2011. An identical number of patients from NSQIP were matched to those from UHC resulting in a total of 10,936 records. LIHR patients had shorter duration of wait from admission to operation (p < 0.05). Conversely, LIHR patients had longer operating time (p < 0.05), duration of anesthesia (p < 0.05), and time in the operating room (p < 0.05).Overall complication rate was higher in open (3.1 vs. 1.8 %, p < 0.05). Cost favored open over LIHR ($4360 vs $5105). The cost discrepancy mainly stemmed from LIHR supplies ($1448 vs. $340; p < 0.05) and OR services ($1380 vs. $1080; p < 0.05).

Conclusion

This study demonstrates the LOS and perioperative outcomes were superior in the LIHR group; however, the overall cost was higher due to the supplies. Advancement in technology, surgeons’ skill level and preference of supplies are all factors in decreasing the overall cost of LIHR.
  相似文献   
68.
Acquired Immune Deficiency Syndrome (AIDS) is one of the serious public health problems in India. AIDS education has been considered as one of the main intervention for control. Sexual route is the major route of transmission of Human Immunodeficiency Virus (HIV); however, approximately 2.5% is transmitted through blood and blood products. The present study was carried out to know the level of awareness about HIV infection and blood donation among first time (190) and repeat (310) voluntary donors of all age groups. One pre-structured questionnaire was circulated among altruistic blood donors. About 96.6% donors want to become repeat donors. Majority of the donors had good knowledge about routes of HIV transmission. According to 97.4% donors, it is transmitted by sexual route, according to 87.4% of donors by sharing needle, according to 85% of donors by blood transfusion and 82.4% of donors believe through vertical transmission. However, 32.4% of the donors, still believe that HIV infection could be transmitted through blood donation. Intense motivational program among donors is needed to remove this myth. Regular donors were convinced the importance of regular and repeat blood donation. They came forward to donate blood for the cause of humanity (80.6%) and the sense of pride (27.79%). First time donors were less motivated by the cause of humanity (56.21%) and volunteered because of peer pressure (26.03%) and motivated by relative or friend. Donors were very alert about precaution to be taken for protecting themselves from danger of HIV infection and priority wise use of safe sexual practice (90%), disposable needles (61.43%) and receive tested blood (45.71%) whenever required. When in need of blood for relatives the donors will give priority to the quality (64.65%) and properly tested blood from voluntary blood donors (86.7%).  相似文献   
69.
Autism spectrum disorders (ASD) and obsessive compulsive disorder (OCD) are often comorbid and are associated with changes in striatal volumes and N-Acetylaspartate (NAA) and glutamate levels. Here, we investigated the relation between dorsal striatal volume and NAA and glutamate levels. We additionally compared striatal volume and shape between ASD, OCD and controls. T1-weighted magnetic resonance (MR) images, proton spectra (1H-MRS) in the left striatum, and phenotypic information were collected from 54 children with ASD, 32 with OCD, and 56 controls (aged 8–13 years) in a four-site study. Dorsal striatal volume and shape were determined using the FMRIB integrated registration and segmentation tool (FIRST). Spectra were processed with Linear Combination Model. The relationship of left striatal volume with NAA and glutamate was investigated, and group comparisons were performed for NAA levels and for bilateral striatal volume and shape. NAA levels were lower in subjects with ASD compared with controls (t=2.86, p=0.005) and were associated with striatal volume (β=0.37, t=2.78, p=0.008). Glutamate levels were also associated with volume in the ASD group (β=0.38, t=2.46, p=0.018). No group differences were found for striatal volume or shape, but a post-hoc diagnosis-by-hemisphere interaction (F(2,129)=3.86, p=0.024) revealed greater asymmetry (right>left) in striatal volume for the disorder-groups compared with controls. Our findings show involvement of NAA and glutamate in striatal volume in ASD and suggest greater asymmetry in paediatric ASD and OCD compared with controls, pointing to overlapping subcortical abnormalities. The lower NAA in ASD reflects reduced neuronal integrity or impaired neuronal functioning.  相似文献   
70.
BACKGROUND/AIMS: The mechanisms of nitric oxide (NO) production by bacteria in the oral cavity are still not clearly defined but salivary streptococci have been reported to generate NO. The aim of this study was to clarify the mechanism of nitrite metabolism and generation of NO by Streptococcus mutans, a major pathogen of dental caries. METHODS: We searched the genomic database of oral pathogens for nitrite reductase and used a polymerase chain reaction (PCR) to clone the nirJ gene from S. mutans GS5. His-tagged recombinant NirJ protein was expressed in Escherichia coli BL21 and characterized. We constructed a nirJ gene-disrupted mutant strain of S. mutans (DeltanirJ) to analyze the physiological significance of nirJ. RESULTS: S. mutans generates NO from nitrite, probably as a result of the possession of nitrite reductase. We cloned the nirJ gene from S. mutans GS5 by PCR. The recombinant NirJ protein catalyzed the reduction of nitrite with a K(m) value of 3.37 microM and a specific activity of 2.5 micromol/min/mg of protein at 37 degrees C. Biochemical analysis revealed that the nitrite-reducing activity of the mutant (DeltanirJ) strain was significantly lower than that of the wild-type strain. The growth of the mutant strain, but not of the wild-type strain, was strongly suppressed by the presence of physiological levels of nitrite ( approximately 0.2 mM) in saliva. CONCLUSION: These observations suggest that the elimination of nitrite and/or the generation of NO are important for the survival of S. mutans in the oral cavity.  相似文献   
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