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61.
During annual rounds of mass treatment against onchocerciasis, women who are pregnant or nursing neonates should not to be offered ivermectin. The aim of the present study was to determine how many women were not treated, as a result of this policy, in four villages in south-eastern Nigeria. Of the 1714 women of reproductive age present during the 2000 round of mass treatment, 599 (35%) were excluded because they were pregnant or nursing babies aged < 1 month. Most (56%) of the 599 excluded women were, however, treated individually later in the year. Of the 264 excluded women who did not receive a dose of ivermectin at all in 2000, 123 (47%) said they would have actively sought ivermectin treatment had they been made aware of the short duration of exclusion for nursing. If they had all known of the short duration of the exclusion and when and how to locate and receive treatment in their villages after the round of mass treatment, 91% of the women excluded from the round of mass treatment would probably have been treated later in the year. Better treatment systems, follow-up and health education, targeted at pregnant and lactating women, would improve treatment coverage of this group after parturition and early nursing.  相似文献   
62.
The symptoms of carpal tunnel syndrome, a compression neuropathy of the median nerve at the wrist, are aggravated by wrist motion, but the effect of these motions on median nerve motion are unknown. To better understand the biomechanics of the abnormal nerve, it is first necessary to understand normal nerve movement. The purpose of this study was to evaluate the deformation and displacement of the normal median nerve at the proximal carpal tunnel level on transverse ultrasound images during different wrist movements, to have a baseline for comparison with abnormal movements. Dynamic ultrasound images of both wrists of 10 asymptomatic volunteers were obtained during wrist maximal flexion, extension and ulnar deviation. To simplify the analysis, the initial and final shape and position of the median nerve were measured and analyzed. The circularity of the median nerve was significantly increased and the aspect ratio and perimeter were significantly decreased in the final image compared with the first image during wrist flexion with finger extension, wrist flexion with finger flexion and wrist ulnar deviation with finger extension (p < 0.01). There were significant differences in median nerve displacement vector between finger flexion, wrist flexion with finger extension and wrist ulnar deviation with finger extension (all p's < 0.001). The mean amplitudes of median nerve motion in wrist flexion with finger extension (2.36 ± 0.79 normalized units [NU]), wrist flexion with finger flexion (2.46 ± 0.84 NU) and wrist ulnar deviation with finger extension (2.86 ± 0.51 NU) were higher than those in finger flexion (0.82 ± 0.33 NU), wrist extension with finger extension (0.77 ± 0.46 NU) and wrist extension with finger flexion (0.81 ± 0.58 NU) (p < 0.0001). In the normal carpal tunnel, wrist flexion and ulnar deviation could induce significant transverse displacement and deformation of the median nerve.  相似文献   
63.
OBJECTIVE: Transabdominal ultrasound (US) is the most frequently used imaging method for the diagnosis of choledocholithiasis. The aim of this prospective study was to evaluate the diagnostic accuracy of high-resolution US in the diagnosis of common bile duct stones depending on the operator's experience and in comparison with endoscopic retrograde cholangiography (ERC) as the gold standard. MATERIAL AND METHODS: From April 2003 through November 2004, 126 patients referred because of clinically and biochemically suspected common bile duct stones were included in the study. Two patients were excluded because they refused to undergo ERC. Consequently, the study comprised 124 patients (86 F, 38 M, mean age 63.2 years, range 21-91 years). High-resolution US was performed (2-5 MHz sector scanner; Siemens Elegra, Erlangen, Germany) by operators who were unaware of the results of other imaging procedures. The definitive diagnosis was established by means of ERC. RESULTS: Thirty-five out of 124 patients were investigated by experienced examiners. Twenty-seven of 35 patients (77%) were found to have stones at ERC. Bile duct stones were correctly found by US in 22 out of 27 patients (sensitivity 82%, 95% CI: 63-92). Of the 8 patients without stones at ERC, one false-positive diagnosis was made with US (specificity 88%, 95% CI: 53-98). Correct diagnoses were made in 29 out of 35 (accuracy 83%, 95% CI: 67-92) patients investigated by experienced examiners. Eighty-nine out of 124 patients were investigated by less-experienced examiners. Fifty-four of 89 patients (61%) were found to have stones at ERC. Choledocholithiasis was found correctly in only 25 out of 54 patients (sensitivity 46%, 95% CI: 34-59). Of the 35 patients without stones at ERC, three false-positive diagnoses were made with US (specificity 91%, 95% CI: 78-97). In conclusion, correct diagnoses were observed in 57 of 89 patients (accuracy 64%, 95% CI: 54-73) investigated by less-experienced examiners (p<0.05 in comparison with the results of experienced examiners). CONCLUSIONS: High-resolution US carried out by experienced examiners has a high diagnostic accuracy in the diagnosis of choledocholithiasis. Therefore, good training and continued experience are prerequisites for successful sonographic detection of bile duct stones using US. Under these conditions, further expensive and invasive methods such as ERC, magnetic resonance cholangiopancreatography and endoscopic ultrasonography may not be necessary in cases with a clear sonographic diagnosis.  相似文献   
64.
Pandemic (H1N1) 2009 influenza virus (pH1N1/09) infection spread rapidly around the globe, leading to a phase 6 pandemic level of alert declared in June 2009. The WHO declared the end of the pandemic in August 2010. Although for the majority of infected patients, it manifest as a mild, self-limiting illness, a proportion appeared to follow an adverse clinical course, requiring higher level care and aggressive management strategies. Experience with previous pandemics suggests that H1N1 will continue to circulate for many years. The aim of this review is to evaluate data from published case series reporting patients with pH1N1/09 influenza to identify clinical markers of severe disease. Comorbid illnesses including chronic lung disease, obesity and pregnancy have been shown to confer increased risk of severe infection. Admission vital signs, laboratory investigations and chest radiographic features can guide admitting clinicians to stratify patients’ risk of severe disease, however, the currently available severity scoring tools have only a limited role in risk assessment. Knowledge of high risk parameters remains important for clinicians triaging patients with suspected pH1N1/09 influenza and to inform strategies for future pandemics.  相似文献   
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66.
Increased afterload results in ‘pathological’ cardiac hypertrophy, the most important risk factor for the development of heart failure. Current in vitro models fall short in deciphering the mechanisms of hypertrophy induced by afterload enhancement. The aim of this study was to develop an experimental model that allows investigating the impact of afterload enhancement (AE) on work-performing heart muscles in vitro. Fibrin-based engineered heart tissue (EHT) was cast between two hollow elastic silicone posts in a 24-well cell culture format. After 2?weeks, the posts were reinforced with metal braces, which markedly increased afterload of the spontaneously beating EHTs. Serum-free, triiodothyronine-, and hydrocortisone-supplemented medium conditions were established to prevent undefined serum effects. Control EHTs were handled identically without reinforcement. Endothelin-1 (ET-1)- or phenylephrine (PE)-stimulated EHTs served as positive control for hypertrophy. Cardiomyocytes in EHTs enlarged by 28.4?% under AE and to a similar extent by ET-1- or PE-stimulation (40.6 or 23.6?%), as determined by dystrophin staining. Cardiomyocyte hypertrophy was accompanied by activation of the fetal gene program, increased glucose consumption, and increased mRNA levels and extracellular deposition of collagen-1. Importantly, afterload-enhanced EHTs exhibited reduced contractile force and impaired diastolic relaxation directly after release of the metal braces. These deleterious effects of afterload enhancement were preventable by endothelin-A, but not endothelin-B receptor blockade. Sustained afterload enhancement of EHTs alone is sufficient to induce pathological cardiac remodeling with reduced contractile function and increased glucose consumption. The model will be useful to investigate novel therapeutic approaches in a simple and fast manner.  相似文献   
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69.
Aim:  The application of ultrasound may be suitable for evaluating the effects of intestinal cytoskeletal rearrangement of the duodenum and colon as a result of exposure to live Giardia lamblia trophozoites. We studied the sonographic appearance of the duodenum and colon in giardiasis compared with amebiasis and healthy subjects.
Methods:  Sonographic images obtained from 100 consecutive patients with symptomatic giardiasis were compared to those taken from 40 patients with amebiasis and 40 healthy subjects. B-mode ultrasound examination of the duodenum and colon was performed using a 7.5 MHz annular array transducer. Gray scale images with water contrast were acquired.
Results:  Normal duodenum and colon echoanatomy were demonstrated. Giardial lesions of the duodenum and colon were associated with increased wall thickness when compared with healthy subjects ( P  < 0.05). Furthermore, giardial lesions were characterized by increased wall echogenicity, flattening or loss of duodenal folds and/or colonic haustration, hyperechoic floating foci (HFF) demonstrating chaotic motility, increased peri-lesional tissue echogenicity, and altered colonic peristalsis. In amebiasis, focal hyperechoic wall thickening was seen at lesion sites identified as amebomas with increased wall echogenicity, but otherwise normal duodenal folds and colonic haustration. There were no HFF with chaotic motility, rather intestinal contents showed bulk motility in patients with amebiasis. There was no focal colonic wall motion abnormality observed.
Conclusion:  B-mode imaging with water contrast demonstrated details of duodenal and colonic echoanatomy. There were sonographic features of giardial lesions of the duodenum and colon that were distinct from those in amebiasis and healthy subjects.  相似文献   
70.
Sepsis is a deadly disease characterized by considerable derangement of the proinflammatory, anti-inflammatory and coagulation responses. Protease-activated receptor 1 (PAR1), an important regulator of endothelial barrier function and blood coagulation, has been proposed to be involved in the lethal sequelae of sepsis, but it is unknown whether activation of PAR1 is beneficial or harmful. Using a cell-penetrating peptide (pepducin) approach, we provide evidence that PAR1 switched from being a vascular-disruptive receptor to a vascular-protective receptor during the progression of sepsis in mice. Unexpectedly, we found that the protective effects of PAR1 required transactivation of PAR2 signaling pathways. Our results suggest therapeutics that selectively activate PAR1-PAR2 complexes may be beneficial in the treatment of sepsis.  相似文献   
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