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991.
OBJECTIVE: To determine whether changes in graduate medical education (GME) funding have had an impact on emergency medicine (EM) residency training programs. METHODS: A 34-question survey was mailed to the program directors (PDs) of all 115 Accreditation Council for Graduate Medical Education (ACGME)-accredited EM residency programs in the United States in the fall of 1998, requesting information concerning the impact of changes in GME funding on various aspects of the EM training. The results were then compared with a similar unpublished survey conducted in the fall of 1996. RESULTS: One hundred one completed surveys were returned (88% response rate). Seventy-one (70%) of the responding EM residency programs were PGY-I through PGY-III, compared with 55 (61%) of the responding programs in 1996. The number of PGY-II through PGY-IV programs decreased from 25 (28%) of responding programs in 1996 to 17 (16%). The number of PGY-I through PGY-IV programs increased slightly (13 vs 10); the number of EM residency positions remained relatively stable. Fifteen programs projected an increase in their number of training positions in the next two years, while only three predicted a decrease. Of the respondents, 56 programs reported reductions in non-EM residency positions and 35 programs reported elimination of fellowship positions at their institutions. Only four of these were EM fellowships. Forty-six respondents reported a reduction in the number of non-EM residents rotating through their EDs, and of these, 11 programs reported this had a moderate to significant effect on their ability to adequately staff the ED with resident physicians. Sixteen programs limited resident recruitment to only those eligible for the full three years of GME funding. Eighty-seven EM programs reported no change in faculty size due to funding issues. Sixty-two programs reported no change in the total number of hours of faculty coverage in the ED, while 34 programs reported an increase. Three EM programs reported recommendations being made to close their residency programs in the near future. CONCLUSIONS: Changes in GME funding have not caused a decrease in the number of existing EM residency and fellowship training positions, but may have had an impact in other areas, including: an increase in the number of EM programs structured in a PGY-I through PGY-III format (with a corresponding decrease in the number of PGY-II through PGY-IV programs); a decrease in the number of non-EM residents rotating through the ED; restriction of resident applicants who are ineligible for full GME funding from consideration by some EM training programs; and an increase in the total number of faculty clinical hours without an increase in faculty size.  相似文献   
992.
A modification of the Picou and Taylor-Roberts Model was used to estimate rates of total body protein synthesis (S), breakdown (C), and amino nitrogen (N) flux (Q) in the metabolic N pool of five obese females. The subjects were fed egg white albumin at 1.5/kg ideal body weight (IBW) and total calories at 1.2 times the basal energy expenditure (fat:carbohydrate = 30%:50%) as a formula diet (period 1, 1 wk). This was followed by 3 wk during which the nonprotein calories were omitted (period 2, protein-sparing modified fast [PSMF]) and a 1-wk total fast (period 3). Estimates of body protein turnover and skeletal protein breakdown were made during the last 60 and 48 hr, respectively, of each period. Q, S, and C were 223 ± 22, 154 ± 22, and 150 ± 22 g protein24 hr, respectively, for period 1. These values were unchanged at the end of period 2. Total fasting decreased Q and S by 36% and 27%, respectively (p < 0.001), but C remained unchanged. Skeletal protein breakdown, as estimated by urinary Nτ-methylhistidine excretion, was 108 ± 47 μmole in period 1, 79 ± 51 μmole in period 2 (p < 0.01), and 100 ± 49 μmole in period 3, representing 16 ± 5%, 12 ± 5% (p < 0.01), and 16 ± 4% of whole body breakdown. N balance was unchanged in period 1 (?0.4 ± 1.2 g N) and the final week of period 2 (?0.4 ± 1.5 g N), but was ?5.8 ± 0.6 g N in period 3. These data indicate that weight reduction with a PSMF is associated with a maintenance of total body protein turnover parameters and N balance but a reduction in skeletal protein breakdown, whereas a total fast causes a marked reduction in whole body protein synthesis and amino N flux with little change in the rate of total body and skeletal protein breakdown, resulting in a negative N balance. The minimization of N losses that develops after prolonged starvation is achieved at rates of whole body and skeletal protein breakdown similar to those found when the diet is adequate, suggesting that endogenous fat-derived fuels are as effective as exogenous energy in limiting protein catabolism. However, protein intake is necessary to maintain whole body protein synthesis under these conditions.  相似文献   
993.
The ability of selenious acid to reverse selenium deficiency in eight adult home TPN patients was assessed. Initially, deficiency was documented by comparing both plasma selenium levels in patients (means = 0.035 micrograms/g) to those of 10 controls (means = 0.117 micrograms/g) (p less than 0.001) and by comparing erythrocyte glutathione peroxidase (GSHPx) activity, as mumol NADPH oxidized/g Hb/min, in patients (means = 8.93) to controls (means = 31.76) (p less than 0.002). Subsequently, patients added 100 micrograms/day of selenious acid to their total parenteral nutrition solutions. Postsupplementation selenium status demonstrated a mean plasma level of 0.101 micrograms/g and a mean erythrocyte GSHPx activity of 17.56. Statistically, patients' plasma selenium levels were significantly different (p less than 0.001) when compared to pretreatment levels. Additionally, there was no significant difference between the restored levels and the levels of the controls. Postsupplementation erythrocyte GSHPx activity (means = 17.56) was not significantly different from the initial patient values, although activity did double. Additionally, there existed a significant difference between the postsupplementation enzyme activity and the controls (p less than 0.03). We conclude that selenious acid is able to normalize deficient plasma levels but not deficient erythrocyte GSHPx activity.  相似文献   
994.
Retrospective analysis of 139 ventilation-perfusion (V/Q) lung scans obtained for suspected pulmonary embolism (PE) was undertaken, using the Biello criteria for interpretation. All scans were correlated with chest radiographs obtained within 24 hours and with pulmonary angiograms obtained within 72 hours of the V/Q study. The prevalence of PE in the high-, intermediate-, and low-probability groups was 89.5%, 49.3%, and 3.6%, respectively. Using minor modifications of these criteria, V/Q scans interpreted as high or low probability had a sensitivity of 97.1%, specificity of 94.3%, and accuracy of 95.7%. Perfusion defects corresponding to radiographic abnormalities that were present for at least 10 days were less likely to be associated with PE. Separate analysis of 27 perfusion-only lung scans that met all other criteria for inclusion in the study confirmed the nonspecificity of perfusion-only lung imaging and indicated the need for ventilation imaging with Tc-99m-DTPA aerosol or Kr-81m gas for portable studies.  相似文献   
995.
Brains, spleens and livers of 2214 murids, 27 shrews and 7 dormice, trapped at 7 sites in Rhodesia, were tested in 277 pools for the presence of Rift Valley Fever virus. There were no isolations of Rift Valley Fever, but 69 isolations of an unidentified virus were obtained. Sixteen out of 867 sera had low-titre haemagglutination-inhibition activity against Rift Valley Fever antigen, but only one out of 1260 sera had neutralizing antibody. The evidence suggests that murids fail to encounter infection in nature and are unlikely to play a role in circulation and dissemination of Rift Valley Fever virus. Four out of seven widely distributed species of muried, Rhabdomys pumilio, Saccostomys campestris, Aethomys chrysophilus and Lemniscomys griselda, were shown to be capable of circulating amounts of virus likely to be infective for mosquitoes.  相似文献   
996.
Ninety patients who had suspected or confirmed fenestral or cochlear otosclerosis underwent CT examination. Foci of demineralization in the otic capsule were discovered in 20 ears (12 patients). Audiometric studies of the 12 patients revealed sensorineural hearing loss (SNHL) with distinct correlation of CT findings with progressivity and with involvement of the frequency level subtended by the specific area of the cochlea involved. Foci of abnormal increased density, presumably representing the healed phase of this disorder, were found less frequently than expected. There was a predilection for the basilar turn. All patients had static SNHL in the higher frequencies. The healed phase of this disorder is probably not consistently diagnosable with CT.  相似文献   
997.
998.
Morbidly obese adults are at increased risk for perioperative thrombotic complications. Antithrombin III (AT III) is a major endogenous anticoagulant and its deficiency is associated with more frequent thrombotic diseases. We measured AT III quantity and function in 23 morbidly obese adults and in 19 otherwise identical people who had reduced their mean weight to 160% of ideal body weight. Both groups were compared to normal weight controls (less than 120% ideal body weight). Serum and plasma AT III function and serum AT III antigenic concentration were significantly lower in the morbidly obese people compared to the weight reduced group in all three assays. The reduced group had values within the normal range of the normal weight group. In addition, three patients studied both before and after weight loss had similar significant changes in their AT III. We conclude that AT III is reduced in morbidly obese adults and normalizes as weight is reduced. Possible mechanisms of this deficiency and therapeutic approaches are considered.  相似文献   
999.
Technetium-99m pyridoxylideneglutamate (P.G.) cholescintigraphy   总被引:1,自引:0,他引:1  
  相似文献   
1000.
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