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81.
OBJECTIVES: Although muscular dystrophy (MD) affects primarily striated muscles, smooth muscle cells of the gastrointestinal tract may also be involved. We recorded gastric electrical activity and gastric emptying time (GET) in children with MD at initial presentation and at 3-yr follow-up in order to detect gastric motor abnormalities and study their evolution along the clinical course. METHODS: Twenty children with MD (median age: 4.6 yr; range age: 3-7 yr) were investigated by means of ultrasonography, for measuring GET, and by electrogastrography (EGG); 70 children served as controls. RESULTS: Ten patients had Duchenne muscular dystrophy (DMD) and 10 Becker muscular dystrophy (BMD). GET was significantly more delayed in MD patients (DMD, median: 195 min; range 150-260 min; BMD, median: 197 min; range: 150-250 min) than in controls (median: 150 min; 110-180 min; p < 0.05); it markedly worsened at the follow-up in DMD (median: 270 min; range 170-310 min; p < 0.001 vs controls) but not in BMD patients (median: 205 min; 155-275 min; p < 0.05 vs DMD). Baseline EGG showed a significantly lower prevalence of normal rhythm and significantly higher prevalence of dysrhythmias in both groups of patients as compared to controls (% of normal rhythm: DMD 66.7 +/- 8.2, BMB 67.2 +/- 11.5, controls 85.3 +/- 7.2, p < 0.001; % of tachygastria: DMD 28.4 +/- 8.0, BMB 29.8 +/- 12.3, controls 10.6 +/- 5.1, p < 0.001; % of dominant frequency instability coefficient: DMD 36.1 +/- 6.0, BMB 33.2 +/- 2.9, controls 17.9 +/- 7.1, p < 0.001); furthermore, no difference in fed-to-fasting ratio of the dominant EGG power was found between the two groups and controls (DMD 2.84 +/- 1.27, BMB 2.82 +/- 0.98, controls 3.04 +/- 0.85, ns). However, at the follow-up no significant change in the prevalence of normal rhythm and dysrhythmias occurred in both groups (ns vs baseline values), whereas only DMD patients showed a marked reduction in fed-to-fasting power ratio (0.78 +/- 0.59; p < 0.001 vs controls and BMD; p < 0.05 vs baseline), which correlated with the progressive neuromuscular weakness occurring in DMD subjects (r, 0.75; p < 0.001). CONCLUSIONS: In children with MD, there is an early abnormality in gastric motility that is due to deranged regulatory mechanisms, whereas contractile activity of smooth muscle cells seems to be preserved. At the follow-up, DMD patients exhibited a progressive failure in neuromuscular function, which was accompanied by a gastric motility derangement with worsening in GET and in EGG features suggesting an altered function of gastric smooth muscle cells.  相似文献   
82.
Aims Smoking cessation treatment trials often require that smokers quit on or before a protocol‐defined date. The goals of this paper were to: (1) identify factors associated with adherence to a protocol‐defined quit date and (2) determine whether such adherence predicts cessation outcome (relapse). Design A quasi‐experimental secondary analysis of data collected from a randomized placebo‐controlled trial of fluoxetine (60 mg or 30 mg) versus placebo for smoking cessation. Setting and participants Clinic‐based smoking cessation treatment program comprising 989 non‐depressed smokers. Intervention Participants received cognitive behavioral therapy for smoking cessation and either study medication or placebo for 10 weeks. They were required to set a quit date within 2 weeks of their second study visit (by visit 4). Findings Significant predictors of quit date adherence were low nicotine dependence and active drug treatment. High‐dose fluoxetine (60 mg) and male gender were protective against relapse. Adherence to quit date was not an independent predictor of relapse; instead there was a significant interaction between quit date adherence and gender. Among non‐adherers to the quit date, women were more than 2.5 times as likely as men to relapse; among adherers to the quit date, women were only 1.3 times as likely as men to relapse. Conclusions Although women were more likely than men to relapse regardless of quit date adherence, adherence was strongly protective against relapse for women.  相似文献   
83.
OBJECTIVE: To evaluate effect of age on hypertensive status in chronic kidney disease (CKD). METHODS: We studied 459 prevalent CKD patients (stages 2-5, no dialysis), grouped by age (< 55, 55-64, 65-74, >or= 75 years), undergoing clinical blood pressure (CBP) and ambulatory blood pressure (ABP) measurement. RESULTS: Prevalence of diabetes, left ventricular hypertrophy and previous cardiovascular disease progressively increased with aging; glomerular filtration rate (GFR) and hemoglobin decreased. Achievement of CBP target decreased from 16% in patients < 55 years to 6% in those >or= 75 years (P = 0.023). ABP 24-h systolic rose while diastolic decreased, with a consequent pulse pressure increase from 45 +/- 8 to 65 +/- 14 mmHg (P < 0.0001). Age, proteinuria, diabetes, cardiovascular disease and anemia but not GFR predicted higher 24-h pulse pressure. CBP overestimated systolic/diastolic daytime ABP by 14 +/- 18/7 +/- 11 mmHg on average, a greater difference in older than younger groups (P < 0.005). Conversely, CBP night-time ABP difference did not vary among groups (24 +/- 20/16 +/- 11 mmHg). These age-dependent differences determined a rising prevalence of white-coat hypertension (from 19 to 40%, P = 0.001) and night/day ratio of at least 0.9 (from 43 to 66%, P = 0.0004). Age, diabetes, left ventricular hypertrophy and anemia but not GFR predicted nondipping status. Among the oldest patients, 13% had diastolic CBP below 70 mmHg, with 48% below the corresponding values of daytime (< 69 mmHg) or night-time ABP (< 60 mmHg). CONCLUSION: In CKD, prevalence of white-coat hypertension, nondipping status and potentially dangerous low diastolic ABP increases with aging. This suggests wider use of ABP monitoring in older patients and need for trials addressing identification of an age-specific blood pressure target.  相似文献   
84.
Leukocytes contribute to the pathogenesis of thrombosis in essential thrombocythemia (ET) through recently discovered mechanisms of activation and interaction with platelets and endothelial cells. To evaluate whether an increased leukocyte count was associated with thrombosis and whether this effect can be modulated by therapy, we analyzed the clinical course of 439 patients with ET followed at the Ospedali Riuniti di Bergamo. The strength of the association was measured at diagnosis or before thrombotic events by multivariable analyses carried out using data at baseline as well as time-varying covariates. The results showed that (1) an increased leukocyte count at diagnosis was associated with thrombosis during follow-up ("baseline analysis," relative risk [RR] 2.3, 95% confidence interval [CI] 1.4-3.9, P = .001); (2) hydroxyurea (HU) lowered leukocytosis and reduced the strength of the association between leukocytosis and thrombosis ("time-dependent analysis," RR 1.6, 95% CI 0.9-2.0, not significant [NS]); (3) the association of leukocytosis and thrombosis was more evident in untreated low-risk patients (RR 2.7, 95% CI 1.2-6.4, P = .01) compared with HU-treated high-risk patients (RR 1.6, 95% CI 0.8-3.2, NS); and (4) the presence of JAK2 V617F was not identified as a risk factor for thrombosis during follow-up despite a significant association between the mutation and leukocytosis. We suggest validation of these findings in prospective clinical studies.  相似文献   
85.
86.
Headache and recurrent abdominal pain (RAP) are common disorders in children and adolescents, frequently referred to paediatricians. Both disorders show similarities in trigger and comorbid factors, their burden on family and individual life, and a paroxysmal trend with risks of chronicization over time. However, very few studies have compared directly headache and RAP. The main aim of this study was to compare the psychological profile of headache and RAP patients vs. healthy controls. A total of 210 children and adolescents [99 boys, 111 girls; age range 4-18 years; mean age (m.a.) = 11.04, SD 4.05] were assessed: 70 headache patients (m.a. 12.4 years; SD 2.9; F = 35, M = 35), 70 RAP patients (m.a. 9 years; SD 3.6; F = 30, M = 40) and 70 controls (m.a. 11.7 years; SD 4.6; F = 46, M = 24). The diagnoses had been made according to international systems of classification both for headache (ICHD-II criteria) and RAP (Rome II criteria). The psychological profile had been made according to the Child Behaviour Checklist 4-18 (CBCL). anova one-way analysis was used to compare CBCL scales and subscales between groups. Headache and RAP showed a very similar trend vs. control for the main scales of the CBCL, with a statistically significant tendency to show problems in the Internalizing scale (anxiety, mood and somatic complaints) and no problems in the Externalizing (behavioural) scale. Only for the Attention Problems subscale migraineurs showed a significant difference compared with RAP. In conclusion, headache and RAP show a very similar psychological profile that should be considered not only for diagnostic and therapeutic purposes, but also from the aetiological aspect.  相似文献   
87.
Heart Failure Reviews - Obstructive (OA) and central apneas (CA) are highly prevalent breathing disorders that have a negative impact on cardiac structure and function; while OA promote the...  相似文献   
88.

Introduction

Catheter ablation (CA) is an established therapy for atrial fibrillation (AF). The SmartTouch catheter (STc) provides information about catheter tip to tissue contact force (CF). The Surround Flow catheter (SFc) provides a uniform cooling of the tip during ablation. We sought to analyze the impact of STc and SFc on CA of paroxysmal AF in terms of feasibility and acute efficacy.

Methods and results

Sixty-three patients (mean age 57.6?±?9.8 years, 53 males) with paroxysmal AF underwent pulmonary veins (PVs) antral isolation, by using standard ThermoCool catheter (TCc) in 21, STc in 21, and SFc in 21. Total procedural, fluoroscopy, and radiofrequency (RF) delivery times; percentage of persistently deconnected PVs after 30 min; and percentage of isolated PVs at the end of the procedure were measured. The use of both STc and SFc obtained a reduction of fluoroscopy time (TCc 34?±?18 min, STc 20?±?10 min, p?<?0.001; SFc 21?±?13 min, p?=?0.02 vs TCc) and RF time (TCc 41?±?13 min, STc 30?±?14 min, p?=?0.013; SFc 30?±?9 min, p?<?0.01 vs TCc). The use of STc resulted in a reduction of procedural time (TCc 181?±?53 min, STc 140?±?53 min, p?<?0.001; SFc 170?±?51 min, p?=?NS vs TCc). The percentage of isolated PVs was comparable between groups (TCc 96 % vs STc 98 % vs SFc 96 %; p?=?NS). The percentage of deconnected PVs at 30 min was lower in TCc (89 %) than in STc (95 %) and in SFc (95 %) group (p?<?0.05).

Conclusions

Both STc and SFc allowed a simplification of CA of paroxysmal AF. In addition, they reduced early PVs reconnection.

Condensed abstract

Sixty-three patients with paroxysmal AF underwent ablation by standard ThermoCool, SmartTouch, or Surround Flow catheter. Both the SmartTouch and the Surround Flow significantly reduced radiofrequency and fluoroscopy times, as well as pulmonary veins reconnection rate at 30 min. Moreover, the SmartTouch reduced overall duration of the procedure.  相似文献   
89.
Objective. To assess the relationship between clinical pictureand neuroimaging in patients affected by SLE with and withoutneuropsychiatric (NP) involvement. Methods. One hundred and seven SLE patients including 66 withNP involvement (NPSLE) with focal or diffuse presentation and41 without underwent single photon emission computed tomography(SPECT) and MRI. Results. After stratification for diffuse or focal NP involvement,in the 52 patients with diffuse presentation, abnormalitiesdetected with MRI or SPECT did not differ from patients withoutNP; however, after combining the two techniques, a normal resultwas more frequently observed in patients without NP involvement(P = 0.010). In the 14 patients with focal presentation, MRIalone and concordant abnormal MRI plus SPECT were more frequentlydetected in the NPSLE group; again normal findings by both techniquessimultaneously applied were more frequently found in SLE patientswithout NP involvement. White matter hyperintense T2-weightedlesions were the most frequent MRI abnormal findings in bothgroups, but the presence of multiple lesions (>5) involvingboth the hemispheres at subtentorial level was limited to NPSLEpatients. Multifocal hypoperfused SPECT areas were more frequentlyobserved in frontal and parietal lobes of NPSLE. Conclusions. Combining SPECT and MRI appears more useful thanthe two techniques alone and may help the clinician in the assessmentof patients with NP involvement since normal findings contemporarilydetected by these two techniques have been rarely observed inpatients with NP involvement especially in those with focalmanifestations where MRI and SPECT were never simultaneouslynormal. KEY WORDS: Systemic lupus erythematosus, Central nervous system, Magnetic resonance imaging, Single photon emission computed tomography Submitted 29 June 2007; revised version accepted 3 December 2007.  相似文献   
90.
BACKGROUND: Vascular endothelial growth factor (VEGF)-165 promotes cardiomyogenesis in chronic myocardial ischemia and nonreperfused myocardial infarction (MI). It is unknown whether this effect is present in reperfused MI. We sought to investigate the effect of VEGF-165 gene therapy on cardiomyogenesis after reperfused MI. METHODS AND RESULTS: Twenty-four Yucatan minipigs underwent thoracotomy and a vascular clamp was placed in the left circumflex artery. Reperfusion was reestablished after 90 minutes, and VEGF-165 gene therapy or placebo was administered. A replication-deficient recombinant human adenovirus serotype 5 was used for gene transfer (Ad5-VEGF165). The same viral vector devoid of VEGF gene (Ad5-beta-galactosidase) was used as placebo. Two administration routes were tested, intramyocardial (IM) injection and circumflex intracoronary (IC) infusion. The pigs were assigned to one of the following groups: IM Ad5-VEGF165 (n = 6), IM Ad5-betaGal (n = 6), IC Ad5-VEGF165 (n = 6), and IC Ad5-betaGal (n = 6). All pigs received 5-bromo-2'-deoxyuridine (BrdU) 250 mg IV twice a week to label cells undergoing DNA replication. The hearts were explanted at 4 weeks. BrdU-labeled cardiomyocytes in the peri-infarct area were counted by a pathologist blinded to group assignment. The number of BrdU-labeled cardiomyocytes per million cells was 4-fold higher in the group receiving IM VEGF-165 (64 +/- 11.4) vs. IM placebo (16 +/- 10.6), P = 0.034. No difference in infarct size or ventricular function was observed between the groups. CONCLUSIONS: IM VEGF-165 gene therapy promotes cardiomyogenesis in reperfused MI. However, no benefit in infarct size or cardiac function was observed at 4 weeks. The origin of these cells remains unknown and needs to be determined.  相似文献   
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