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991.
992.
993.
OBJECTIVE: The purpose of this study was to evaluate the feasibility and safety of manual reduction of torsion of an intrascrotal appendage under ultrasonographic monitoring. METHODS: Fifteen boys with torsion of an intrascrotal appendage, confirmed by scrotal ultrasonography and clinical status, were included in the study. The boys were 6 to 13 years old (mean age, 9 years). They all had painful, unilateral swelling of the scrotum and a palpable, tender nodule on physical examination. Scrotal ultrasonography indicated a single, variably echoic mass corresponding to the intrascrotal appendage. The mass was avascular according to Doppler ultrasonography. Thirteen boys underwent manual reduction under ultrasonographic monitoring. We tried to pull and release the swollen appendage in 8 patients and gently squeezed the appendage in 5. The procedure was considered successful when ultrasonography showed reperfusion in the appendage and the patients stated complete relief of scrotal pain. In 14 boys, follow-up scrotal ultrasonography was performed after the manual reduction. RESULTS: Successful reduction was obtained in 12 (80.0%) of 15 boys. Only 1 boy was regarded as having reduction failure; this patient had intractable pain after the trial reduction, and ultrasonography showed transient vascular flow that promptly disappeared in the appendage. On follow-up ultrasonography, the maximal diameter +/- SD of the intrascrotal appendages significantly decreased from 6.1 +/- 1.2 to 4.0 +/- 1.3 (P=.005) in 11 patients with successful reduction. CONCLUSIONS: Manual reduction under ultrasonographic monitoring seems to be a feasible and effective method for the treatment of torsion of an intrascrotal appendage to immediately relieve pain.  相似文献   
994.
995.
Are Metastases Really Hypovascular in the Arterial Phase?   总被引:2,自引:0,他引:2  
OBJECTIVE: The purpose of this study was to describe enhancement and vascularity characteristics of liver metastases on real-time low-mechanical index contrast-enhanced ultrasonography. METHODS: This retrospective study was approved for chart review by our Research Ethics Board. Informed consent was waived. Fifty metastases (colorectal [n = 28], neuroendocrine [n = 6], pancreatic [n = 6], melanoma [n = 3], and other [n = 7]) in 50 patients (38-84 years, 24 male and 26 female) were analyzed. Contrast-enhanced ultrasonography was performed after intravenous injection of a microbubble contrast agent. Two radiologists independently reviewed digital cine clips and static images for the arterial phase intensity and pattern of enhancement and the presence of dysmorphic vessels. Observations on wash-out included its presence and completeness. Disagreement was resolved by consensus. The interval to peak arterial enhancement and beginning of wash-out were determined. Reader agreement was estimated with the kappa statistic. RESULTS: All but 6 metastases (44/50 [88%]) showed arterial hypervascularity, with dysmorphic vessels in 21 (42%) of 50. The pattern of enhancement was rim in 21 (42%) of 50 and diffuse in 29 (58%) of 50. The time to peak arterial enhancement ranged from 8 to 27 seconds (mean, 15.1 seconds), and the beginning of wash-out ranged from 13 to 50 seconds (mean, 25.2 seconds). Although a thin margin of residual enhancement was seen in 27 (54%) of 50 lesions in the early wash-out phase, all lesions (50/50) showed uniform complete wash-out in the portal phase. CONCLUSIONS: Contrary to popular belief based on computed tomography and magnetic resonance imaging studies, most hepatic metastases, including those thought to be hypovascular, show transient arterial hypervascularity on contrast-enhanced ultrasonography, followed by rapid and complete wash-out initiated within the conventional arterial phase.  相似文献   
996.

Purpose

The aim of this study was to evaluate the efficacy and tolerability of rosuvastatin/ezetimibe combination therapy in Korean patients with high cardiovascular risk.

Methods

This was a 12-week, randomized, double-blind, placebo-controlled, multicenter study. A total of 337 patients were screened. After a 4-week run-in period, 245 of these patients with high or moderately high risk as defined by the National Cholesterol Education Program Adult Treatment Panel III guidelines were randomly assigned. Patients received 1 of 6 regimens for 8 weeks as follows: (1) rosuvastatin 5 mg, (2) rosuvastatin 5 mg/ezetimibe 10 mg, (3) rosuvastatin 10 mg, (4) rosuvastatin 10 mg/ezetimibe 10 mg, (5) rosuvastatin 20 mg, or (6) rosuvastatin 20 mg/ezetimibe 10 mg. The primary outcome variable was percentage change in the level of LDL-C at week 8 of drug treatment. Secondary outcome variables included percentage changes of other lipid variables and achievement rates of LDL-C targets. Tolerability analyses were also performed.

Findings

The percentage change of LDL-C ranged from –45% to –56% (mean, –51%) in the monotherapy groups and from –58% to –63% (mean, –60%) in the combination therapy groups. The percentage change was greater in the pooled combination therapy group than in the counterpart (P < 0.001 for the pooled groups); this difference was more obvious for regimens with a lower statin dose. The percentage reductions of total cholesterol and triglycerides were greater in the combination groups than in the monotherapy groups. The LDL-C target achievement rates were 64% to 87% (mean, 73%) in the monotherapy groups and 87% to 95% (mean, 91%) in the combination groups (P = 0.01 for the pooled groups). The rates were significantly greater in patients receiving the combination therapy than in the monotherapy at lower doses of rosuvastatin. The proportions of patients with various adverse events were not significantly different between the groups.

Implications

Rosuvastatin/ezetimibe combination therapy has better efficacy and target achievement rates than rosuvastatin monotherapy in patients with high cardiovascular risk.  相似文献   
997.
A variant 2677A allele of the MDR1 gene affects fexofenadine disposition   总被引:5,自引:0,他引:5  
BACKGROUND AND OBJECTIVES: There have been considerable disagreements regarding the influence of MDR1 (ABCB1) polymorphisms on the disposition of P-glycoprotein (P-gp) substrates. We speculated that the unknown function of the A allele of exon 21 G2677T/A (Ala893Ser/Thr) provides one of the reasons for the contradictory results. This study was performed to clarify the effects of major MDR1 gene polymorphisms, including a variant A allele in exon 21, on fexofenadine pharmacokinetics. METHODS: We investigated the occurrence of 3 high-frequency single-nucleotide polymorphisms (SNPs) in exons 12 (C1236T), 21 (G2677T/A), and 26 (C3435T) of the MDR1 gene in 232 healthy Koreans, using a polymerase chain reaction-restriction fragment length polymorphism method, and performed haplotype analysis on these 3 SNPs. A single oral dose of 180 mg fexofenadine hydrochloride was administered to 33 healthy Korean male volunteers, who were divided into 6 groups based on the MDR1 genotype for the G2677T/A polymorphism in exon 21 and the C3435T polymorphism in exon 26. RESULTS: A strong linkage disequilibrium was observed among the 3 SNPs. The frequencies of the 4 major haplotypes, 1236C-2677A-3435C, C-G-C, T-G-C, and T-T-T, were 16.4%, 18.6%, 21.6%, and 32.2%, respectively. Fexofenadine disposition varied considerably among the groups. In the 2677AA/3435CC genotype group (n=3), the values of area under the concentration-time curve from time 0 to 24 hours [AUC(0-24)] were significantly lower (P=.014) than those of the other 5 genotype groups (GG/CC, GT/CT, TT/TT, GA/CC, and TA/CT). As compared with the 2677GG/3435CC subjects, the AUC(0-24) values were 17% lower in the 2677AA/3435CC subjects and 47% higher in the 2677TT/3435TT subjects (GG/CC versus AA/CC versus TT/TT, 4017 +/- 1137 ng . h/mL versus 3315 +/- 958 ng . h/mL versus 5934 +/- 2,064 ng . h/mL; P=.018). By stratification for genotypes at position 3435, homozygous 3435TT subjects were found to have significantly higher AUC(0-24) (P=.024) and maximum plasma concentration (P=.040) values than CC subjects [AUC(0-24), 5934 +/- 2064 ng . h/mL versus 3998 +/- 1241 ng . h/mL; maximum plasma concentration, 958 +/- 408 ng/mL versus 673 +/- 242 ng/mL]. CONCLUSIONS: The plasma concentrations of fexofenadine after a single oral administration were lower in 2677AA/3435CC subjects than in subjects with the other 5 genotype combinations of the SNPs of G2677T/A and C3435T. These findings confirm the importance of analyzing MDR1 haplotypes and provide a plausible explanation for the conflicting results regarding the effect of MDR1 polymorphisms on the disposition of P-gp substrates.  相似文献   
998.
OBJECTIVES: Small dense LDL, low density lipoprotein (LDL) particles with small size and high density, is regarded as a significant risk factor for cardiovascular diseases. Diabetes mellitus is one of the conditions accompanied by increased small dense LDL. We analyzed LDL subclass in type 2 diabetics and normal controls with LipoPrint LDL System to investigate the LDL heterogeneity in diabetics and factors affecting it. DESIGN AND METHODS: We selected 40 normal controls and 40 type 2 diabetics with fasting blood glucose level over 7.0 mmol/L and HbA1c level over 7%. LDL subclass was determined with LipoPrint LDL System. LipoPrint LDL System fractionates LDL into seven parts (LDL1-7) by size and LDL3 to LDL7 are defined as small-sized LDL. In addition we estimated 'the percent of small-sized LDL over whole LDL' and defined it as 'small-sized LDL proportion'. RESULTS: Mean small-sized LDL proportion was significantly higher in diabetics (23.4%) than in controls (11.8%) (p<0.001) and small-sized LDL proportion showed positive correlation with blood levels of glucose, HbA1c, total cholesterol, triglyceride, and oxidized LDL and negative correlation with HDL cholesterol level in univariate analysis (p<0.001). Of these parameters, triglyceride, HbA1c, oxidized LDL were statistically significant variables contributing to the small-sized LDL proportion in stepwise multiple regression analysis. CONCLUSIONS: We analyzed small-sized LDL proportion in type 2 diabetics and found that it was significantly increased in diabetics than control subjects and it was independently correlated with triglyceride, HbA1c, oxidized LDL in descending order, which are reflecting lipid metabolism, glycation, and oxidative stress, respectively.  相似文献   
999.
1000.
BACKGROUND/AIMS: Although balloon-occluded retrograde transvenous obliteration (BRTO) has been used as a new procedure for gastric variceal bleeding due to its feasibility and minimal invasiveness, reports regarding the results of BRTO are not well presented in Korea. Therefore, we analyzed the results of our experience in recent 39 months. METHODS: Twenty eight patients who received BRTO for primary hemostasis or secondary prevention of gastric variceal bleeding from December 2001 to March 2005 were analyzed retrospectively. RESULTS: Twenty three men and five women were involved, and the mean age was 53.7+/-9.6 years. Technical and clinical success rates were 89.3% and 85.7%, respectively. Follow-up duration was 17.5+/-12.5 months in 23 patients. Gastric varices disappeared in 78.3% and decreased in 21.7%. Relapses occurred in 4.3% of the patients. Preexisting hepatic encephalopathy improved in all 11 patients. Aggravation of ascites, esophageal varices, portal hypertensive gastropathy were observed in 45.8%, 30.4%, 56.5%, respectively. Increased Child-Pugh score (p < 0.001) and decreased albumin concentration (p = 0.002) were observed 3 days after BRTO, but resolved 7 days later. Increased albumin concentration and decreased Child-Pugh score maintained thereafter. Rebleeding occurred in 3 patients which were caused by esophageal varices. Two-year survival rate was 54.6%. Presence of hepatocellular carcinoma (HCC) (p = 0.001) and Child-Pugh grade (p = 0.033) affected the survival, but HCC was the only independent risk factor (p = 0.010, OR = 15.837) in multivariate analysis. CONCLUSIONS: BRTO is an effective therapeutic procedure for primary hemostasis, secondary prevention, and for improving survival in gastric variceal bleeding patients.  相似文献   
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