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101.
OBJECTIVE: To determine the relationship between baseline plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels and the presence and extent of myocardial ischemia during dobutamine stress echocardiography (DSE). METHODS: NT-proBNP was measured in 170 consecutive patients prior to DSE. Rest wall motion abnormalities (RWMAs) and new wall motion abnormalities (NWMAs) were scored using a 5-point, 17-segment model. Kruskal-Wallis tests were applied to study differences in NT-proBNP levels between patients with normal DSE, RWMAs but no NWMAs, and NWMAs, and (in patients with NWMAs) between those with 1-2, 3-4 and >4 ischemic segments. Univariate and multivariate regression analyses were used to determine the value of NT-proBNP in predicting NWMAs. RESULTS: The median NT-proBNP level was 110 ng/l (interquartile range: 42-389 ng/l). Median NT-proBNP was 59, 321 and 440 ng/l in patients with normal DSE, with RWMAs but no NWMAs, and with NWMAs, respectively (P<0001). Among patients with NWMAs, median NT-proBNP was associated with the number of ischemic segments: 364, 710 and 2376 ng/l in patients with 1-2, 3-4 and >4 ischemic segments, respectively (P<0.001). Elevated NT-proBNP levels were significantly associated with NWMAs (odds ratio per 100 ng/l increase: 1.14, 95% confidence interval: 1.1-1.2) in a multivariate analysis of clinical baseline variables and RWMAs. CONCLUSION: Elevated baseline levels of NT-proBNP are associated with the presence and extent of myocardial ischemia during DSE, independent of the presence of RWMAs.  相似文献   
102.
Exogenous advanced glycation endproducts (AGEs, known atherogenic molecules) abundant in everyday precooked, rich in fat, overheated meals can possibly contribute to the increased risk for diabetes and cardiovascular disease in women with polycystic ovary syndrome (PCOS). The aim of the present study was to investigate the effect of a lipase inhibitor on absorbed food glycotoxins in healthy women and those with PCOS. A 2-day protocol was followed. In the first day, a meal rich in AGE was provided, which on the second day was followed by two 120-mg capsules of lipase inhibitor, orlistat. Serum AGE levels were evaluated at baseline (0 hours), and at 3 and 5 hours postmeal during the study. Thirty-six women were studied, 15 controls (mean age, 28.80 +/- 5.47 years; body mass index, 25.85 +/- 6.73 kg/m(2)) and 21 with PCOS (mean age, 25.29 +/- 5.06 years; body mass index, 30.40 +/- 7.51 kg/m(2)) (University Hospital, Athens, Greece, institutional practice). Serum AGE levels, on day 1, were significantly increased both in the control group and in the PCOS group as compared with basal values (control group, 14.1%; PCOS group, 6.0%; P < .001). The corresponding rise was significantly lower on day 2 when the same meal was combined with orlistat (control group, 4.1%; PCOS group, 2.0%; P < .01). A limitation of the study is that it is a nonplacebo, nonrandomized therapeutic trial where each subject is considered as its own control. In conclusion, this study demonstrated the beneficial effect of orlistat on the absorption of food glycotoxins.  相似文献   
103.
A time-varying parametric spectrum estimation method for analysing non-stationary heart rate variability signals is presented. As a case study, the dynamics of heart rate variability during an orthostatic test is examined. In this method, the non-stationary signal is first modelled with a time-varying autoregressive model and the model parameters are estimated recursively with a Kalman smoother algorithm. The benefit of using the Kalman smoother is that the lag error present in a Kalman filter, as well as in all other adaptive filters, can be avoided. The spectrum estimates for each time instant are then obtained from the estimated model parameters. Statistics of the obtained spectrum estimates are derived using the error propagation principle. The obtained spectrum estimates can further be decomposed into separate components and, thus, the time variation of low- and high-frequency components of heart rate variability can be examined separately. By using the presented method, high resolution time-varying spectrum estimates with no lag error can be produced. Other benefits of the method are the straightforward procedure for evaluating the statistics of the spectrum estimates and the option of spectral decomposition.  相似文献   
104.
OBJECTIVE: To detect origin and course and to evaluate viability in patients with anomalous RCA. DESIGN: 3D coronary MR angiography and viability study using gadolinium-enhanced magnetic resonance imaging (Gd-MRI) was performed. SETTING: A tertiary hospital center. PATIENTS: Four patients, selected from the catheter lab, were studied. RESULTS: Anomalous RCA from the left sinus of Valsalva was identified in all patients. Inferior myocardial infarction was documented in three patients. CONCLUSIONS: Magnetic resonance imaging can non-invasively identify anomalous RCA and perform viability study in the same examination.  相似文献   
105.
Objective. The association between Helicobacter pylori (H. pylori) infection and serum lipid profile is still controversial. The aim of this study was to determine any possible relationship between H. pylori infection and the lipid profile of patients with upper gastrointestinal symptoms. Material and methods. Consecutively selected 20–70 year-old dyspeptic patients who had undergone esophagogastroduodenoscopy were evaluated for H. pylori infection using both the CLO test and Giemsa staining. Serum total cholesterol (C), HDL-C, LDL-C, apo-A1, apo-B and triglyceride levels were measured. Results. A total of 137 patients (median age 52.0 years) were studied. Total cholesterol levels were lower in H. pylori-infected patients than in H. pylori-negative patients (mean±SEM: 199.3±5.9 versus 212.6±4.6 mg/dl, p=0.08). Patients with duodenal ulcer (DU) had significantly lower levels of all measured lipidemic parameters including cholesterol, with the exception of triglycerides, in comparison with either H. pylori-positive or -negative dyspeptic patients (cholesterol: 177.6±6.5 versus 214.6±4.2 mg/dl, p<0.0001). However, there was no difference in the total cholesterol/HDL-C ratio between DU patients and the rest of the dyspeptic patients. Conclusions. Among H. pylori-positive and H. pylori-negative patients there was no difference in lipid profile apart from a trend towards total cholesterol levels being lower in H. pylori-positive patients. However, cholesterol, HDL-C, LDL-C, apo-A and apo-B were all decreased in DU patients even though this reduction did not result in a fall in the total cholesterol/HDL-C ratio. The etiologic factor differentiating the lipid profiles among dyspeptics only in H. pylori-positive patients carrying a DU could be dietetic, microbial, genetic or a combination of all three.  相似文献   
106.
107.
108.

Purpose

The purpose of the present study was to analyze biopsy samples from the subscapularis tendon and from the joint capsule from male patients with shoulder impingement syndrome (SAIS) and compare them with samples from male patients with post-traumatic recurrent shoulder instability. The hypothesis of the study was that patients with SAIS would have more histologic and ultrastructural degenerative changes in their subscapularis tendon and joint capsule than patients with post-traumatic recurrent shoulder instability.

Methods

Male patients scheduled for surgery, with either subacromial decompression or Bankart reconstruction, were included. Four biopsies from each patient were obtained from the capsule and four from the subscapularis tendon during arthroscopic surgery. The histologic characteristics and the presence of glycosaminoglycans were assessed using the light microscope, and the ultrastructure was assessed using a transmission electron microscope.

Results

Eight patients, median age 53 (45–74) years (p?<?0.0001), were included in the impingement group, and 12 patients, median age 27 (22–48) years, were included in the instability group. The histologic assessment revealed significantly higher cellularity and total degeneration score in the capsule (p?=?0.016 and p?=?0.014 respectively) in patients with subacromial impingement compared with the instability patients. The corresponding finding was not made for the subscapularis tendon. The ultrastructural evaluation revealed that the instability patients had more fibrils with a large diameter (indicating less degeneration) in both the subscapularis tendon and the capsule compared with the impingement patients (p?<?0.0001).

Conclusion

Male patients with subacromial impingement have more histologic and ultrastructural degenerative changes in their shoulder compared with patients with post-traumatic recurrent shoulder instability.

Clinical relevance

It appears that in patients with subacromial impingement, the whole shoulder joint is affected and not only the subacromial space. It is the opinion of the authors that intra-articular therapeutic injections could be tried more often in these patients.

Level of evidence

III.
  相似文献   
109.

Background

In countries such as Cyprus the financial crisis and the recession have severely affected the funding and priority setting of the health care system. There is evidence highlighting the importance of population’ preferences in designing priorities for health care settings. Although public preferences have been thorough analysed in many countries, there is a research gap in terms of simultaneously investigating the relative importance and the weight of differing and competing criteria for determining healthcare priority settings. The main objective of the study was tο investigate public preferences for the relative utility and weight of differing and competing criteria for health care priority setting in Cyprus.

Methods

The ‘conjoint analysis’ technique was applied to develop a ranking exercise. The aim of the study was to identify the preferences of the participants for alternative options. Participants were asked to grade in a priority order 16 hypothetical case scenarios of patients with different disease and of diverse socio-economic characteristics awaiting treatment. The sample was purposive and consisted of 100 Cypriots, selected from public locations all over the country.

Results

It was revealed that the “severity of the disease” and the “age of the patient” were the key prioritization criteria. Participants assigned the smallest relative value to the criterion “healthy lifestyle”. More precisely, participants older than 35 years old assigned higher relative importance to “age”, while younger participants to the “severity of the disease”. The “healthy lifestyle” criterion was assigned to the lowest relative importance to by all participants.

Conclusion

In Cyprus, public participation in health care priority setting is almost inexistent. Nonetheless, it seems that the public’s participation in this process could lead to a wider acceptance of the healthcare system especially as a result of the financial crisis and the upcoming reforms implemented such as the establishment of the General System of Health Insurance.
  相似文献   
110.
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