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481.
This study is designed to evaluate the N-terminal pro-BNP (NTproBNP) levels in patients with mitral stenosis (MS) and its possible correlation with clinical and echocardiographic parameters of the disease. The study group consisted of 29 patients with isolated MS (patients with greater mild regurgitation were excluded) and 20 normal control subjects of similar age and gender distribution. Blood samples for NTproBNP were collected at the time of clinical and echocardiographic examination. NTproBNP levels were elevated in patients with MS compared to controls (325 +/- 249 pg/dL [19.9-890] versus 43 +/- 36 pg/dL [5.76-193.3], P < 0.001). Patients with atrial fibrillation had significantly higher NTproBNP levels compared to those with sinus rhythm (561 +/- 281 pg/dL versus 254 +/- 194 pg/dL, P = 0.044). MS patients with sinus rhythm also had higher NTproBNP levels compared to controls (254 +/- 194 pg/dL versus 43 +/- 36 pg/dL, P = 0.00011). NT pro BNP levels correlated to the LA (R = 0.73, P < 0.0001) and RV (R = 0.41, P = 0.042) diameters, mitral valve area (R =-0.45, P = 0.025), mean mitral gradient (R = 0.57, P = 0.003), peak PAP (R = 0.7, P = 0.03), and NYHA functional class (R = 0.61, P = 0.007). In conclusion, serum NTproBNP levels correlate well with echocardiographic findings and functional class in patients with MS and can be used as a marker of disease severity. Additionally, it may have a potential use as an additional noninvasive and relatively cheap method in monitoring disease progression especially in patients with poor echocardiographic windows.  相似文献   
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Purpose

To assess the relationships between mucosal thickness, T1-weighted, T2-weighted signals and restricted diffusion on magnetic resonance imaging (MRI) with the degree of symptoms in patients with incidentally detected inflammatory sinonasal disease.

Materials and methods

Conventional and diffusion-weighted MRI of 100 patients with incidental sinonasal mucosal thickening were prospectively evaluated. There were 53 men and 47 women, with a mean age of 44.6 years ± 15.17 (SD) (range: 18–81 years). Correlations between quantitative values (T1-signal, T2-signal and apparent diffusion coefficient [ADC]) and three different quality of life questionnaires (chronic sinusitis survey, sinonasal outcomes test-22 and nasal obstruction and septoplasty effectiveness scale [NOSE]) were searched using the Spearman correlation test.

Results

The mean SNOT-22 score was 35.81 ± 20.36 (SD) (range: 0–83), CSS score was 4.64 ± 3.42 (SD) (range: 0–14), and NOSE score was 5.91 ± 4.84 (range: 0–18). All patients (100%) had maxillary sinus involvement. Ethmoidal sinus involvement was present in 57% of patients, frontal sinus involvement in 33% and sphenoidal sinus involvement in 27%. Morphologically, 40 patients (40%) had septal deviation, 41 (41%) had maxillary sinus retention cyst and 78 (78%) had hypertrophy of the conchae. No correlations were found between morphological abnormalities, quantitative values and patient scores in none of the questionnaires.

Conclusion

Incidental morphological abnormalities or restricted diffusion of the paranasal sinuses on MRI do not correlate with the degree of symptoms in patients with incidentally detected inflammatory sinonasal disease.  相似文献   
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Inguinal and incisional hernias are the two most common types of hernias caused by abdominal wall weakness and defects in connective tissue. The structure of the extracellular matrix, mainly collagen and metalloproteinases (MMPs), and their regulators have been studied extensively and found to play a significant role in the pathophysiology of hernias. One of the regulators of MMPs, tissue inhibitor metalloproteinases (TIMPs), bind to MMPs and inhibit its activity significantly shifting the balance towards collagen synthesis rather than degradation. Due to their importance in collagen metabolism, their metabolism might be significant in the aetiology of hernias. Our study used immunohistochemical techniques to investigate the possible effects of TIMP 1 and 2 on the samples taken from the abdominal walls of patients with inguinal and incisional hernias, compared them with control patients, and reviewed the literature. In this study, samples of 90 patients (30 patients from control, inguinal hernia, and incisional hernia groups) were taken and analysed. These samples were stained with TIMP‐1 Ab‐2 and TIMP2 Ab‐5 (Clone 3A4) antibodies and evaluated under ×100 magnification. The degree of staining was classified as (a): No staining (0), (b): Staining less than 10% (I), (c): Staining between 10% and 50% (II), (d): Staining more than 50% (III). Statistical analyses were done. No significant difference was found between groups in terms of patient demographics. Smoking and family history of hernia was not found to be associated with TIMP expression. TIMP1 expression was significantly higher in the incisional and inguinal hernia group than in the control group (P < .05), while the level of TIMP2 was higher in the control group. (P < .05). TIMP1 and TIMP2 levels did not significantly differ between incisional and inguinal hernia groups. We found significantly increased TIMP‐1 levels in tissue samples from patients with hernia supporting its suggested role in hernia pathophysiology. Local alterations in MMP and TIMP levels might play a role in the pathogenesis of hernias. Thus detection of TIMP in tissues can be important for clinical use after further validation studies. In the era of molecular medicine, detecting TIMP levels in hernia patients can impact clinical practice.  相似文献   
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Harnessing interactions of functional nano-compartments to generate larger particle assemblies allows studying diverse biological behaviors based on their population states and can lead to the development of smart materials. Herein, thiol-functionalized polymersome nanoreactors are utilized as responsive organelle-like nano-compartments—with inherent capacity to associate into larger aggregates in response to change in the redox state of their environment—to study the kinetics of cascade reactions and explore functions of their collective under different population states. Two nanoreactor populations, glucose oxidase- and horseradish peroxidase-loaded polymersomes, are prepared, and the results of their cascading upon addition of glucose are investigated. The kinetics of resorufin production in associated polymersomes and non-associated polymersome populations are compared, observing a decreased rate upon association. For the associated populations, faster chemical cascading is found when the two types of nanoreactors are associated in a concerted step, as compared to sequential association. The addition of competing agents such as catalase impacts the communication between non-associated polymersomes, whereas such an effect is less pronounced for the associated ones. Altogether, the results showcase the impact of collective associations on enzymatic cascading between organelle-like nanoreactors.  相似文献   
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