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31.

Purpose

To report two cases of solitary unilateral vitreous cyst.

Methods

A complete ocular examination, fundus photography, B-scan ultrasound and spectral-domain optical coherence tomography were performed in both patients.

Results

The first patient (a 39-year-old man) presented with transient blurred vision in the right eye. The second patient (a 78-year-old man) reported transient blurred vision in the right eye when changing head position. He was referred to the Eye Hospital because of vitreomacular traction in the other eye. After examination, a diagnosis of vitreous cyst was made in both cases.

Conclusions

Vitreous cysts are rare clinical findings. They can occur in normal eyes or in eyes with certain ocular pathologies. When a cyst floats into the visual axis area, it can disturb visual function; therefore, patients usually report transient blurring of vision. A prompt clinical examination is necessary for differentiating this rare condition.Key words: Vitreous cyst, Floater, Retinoschisis, Myopia  相似文献   
32.
Hepatic ethoxyresorufin-O-deethylase (EROD) activity was measured in black gobies (Gobius niger) collected from seven sampling sites along the Slovenian coast during spawning and non-spawning periods. Sediments from the same sites were tested for their toxicity and for total polycyclic aromatic hydrocarbon (PAH) content. EROD activity was significantly higher during the non-spawning period in winter than during the spawning period in spring and generally correlated well with increased total PAH content in sediments and with sediment toxicity. An 11-fold increase of EROD activity was induced 48 h after injecting 10 μg g−1 weight of benzo(a)pyrene into black gobies. On the basis of these results and of its ecological characteristics, the black goby is proposed as a suitable candidate for future biomonitoring programmes.  相似文献   
33.
The aim of our retrospective study was to analyze the clinical course and outcome of patients with immunoglobulin A (IgA) nephropathy who presented with macroscopic hematuria and acute kidney injury (AKI). During the period from 1990 to 2005, seven out of 584 adult patients with IgA nephropathy (1.2%) fulfilled the criteria for macroscopic hematuria‐induced AKI. There was an equal gender distribution among our patients, and a rather high average age at presentation (55.7 ± 10.9 years). Four patients who were oliguric upon admission to hospital needed hemodialysis treatment. The average serum creatinine at the time of kidney biopsy was 429.8 ± 377 µmol/L (median value 378). The percutaneous kidney needle biopsies showed focal proliferative crescentic glomerulonephritis of subclass III, according to the Haas scheme, associated with prominent red blood cell tubular casts and acute tubulointerstitial nephritis. Four patients with the most prominent crescents and tubulointerstitial involvement were treated with methylprednisolone. All patients, treated and untreated, recovered their kidney function (the serum creatinine at a median follow‐up of 15 months was 111.7 ± 38 µmol/L). In conclusion, AKI in IgA nephropathy accompanied by macroscopic hematuria appears to have been a reversible condition in our series of patients. Regarding pathogenesis, the kidney biopsy study points to the important role of glomerular bleeding with consequent, widespread obstructive red blood cell tubular casts accompanied by tubular injury and interstitial nephritis.  相似文献   
34.
The concurrence of multiple sclerosis (MS) and brain tumors has been reported, but it is not known whether MS patients are at greater risk of harbouring the latter. The most common cerebral neoplasms reported in MS patients were oligodendroglioma, astrocytoma, glioblastoma and gliomatosis. MS can also present as a mass lesion that mimics a brain tumor. To establish the correct diagnosis radiological follow-up and/or histological confirmation is needed. Two cases of coincidental MS and brain tumors are reviewed. One is a 26-year-old woman with relapsing-remitting MS and an anaplastic oligodendroglioma, the other a 49-year-old woman patient with relapsing-remitting MS and gliomatosis type 2. Both patients were treated with interferon-beta1b and both died from the tumor. The concurrence of MS and brain tumors could be purely coincidental, or the result of neoplastic transformation of reactive glial cells in the areas of demyelination. The combination of a brain tumor and MS, and interferon-beta treatment could also be pure coincidence or an unknown side effect of treatment. Although interferon-beta has been said to function as a tumor-suppressor protein, the influence of long-term treatment of MS patients on cancer development is not known.  相似文献   
35.
Surface free energy of a chemically heterogeneous surface is often treated as an approximately additive quantity through the Cassie equation [Cassie ABD (1948) Discuss Faraday Soc 3:11-16]. However, deviations from additivity are common, and molecular interpretations are still lacking. We use molecular simulations to measure the microscopic analogue of contact angle, Θ(c), of aqueous nanodrops on heterogeneous synthetic and natural surfaces as a function of surface composition. The synthetic surfaces are layers of graphene functionalized with prototypical nonpolar and polar head group: methyl, amino, and nitrile. We demonstrate positive as well as negative deviations from the linear additivity. We show the deviations reflect the uneven exposure of mixture components to the solvent and the linear relation is recovered if fractions of solvent-accessible surface are used as the measure of composition. As the spatial variations in polarity become of larger amplitude, the linear relation can no longer be obtained. Protein surfaces represent such natural patterned surfaces, also characterized by larger patches and roughness. Our calculations reveal strong deviations from linear additivity on a prototypical surface comprising surface fragments of melittin dimer. The deviations reflect the disproportionately strong influence of isolated polar patches, preferential wetting, and changes in the position of the liquid interface above hydrophobic patches. Because solvent-induced contribution to the free energy of surface association grows as cos Θ(c), deviations of cos Θ(c) from the linear relation directly reflect nonadditive adhesive energies of biosurfaces.  相似文献   
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38.
AIM To investigate whether duodenal lesions induced by major venous occlusions can be attenuated by BPC 157 regardless nitric oxide(NO) system involvement.METHODS Male Wistar rats underwent superior anterior pancreaticoduodenal vein(SAPDV)-ligation and were treated with a bath at the ligated SAPDV site(BPC 157 10 μg, 10 ng/kg per 1 mL bath/rat; L-NAME 5 mg/kg per 1 m L bath/rat; L-arginine 100 mg/kg per 1 mL bath/rat, alone and/or together; or BPC 157 10 μg/kg instilled into the rat stomach, at 1 min ligation-time). We recorded the vessel presentation(filled/appearance or emptied/disappearance) between the 5 arcade vessels arising from the SAPDV on the ventral duodenum side, the inferior anterior pancreaticoduodenal vein(IAPDV) and superior mesenteric vein(SMV) as bypassing vascular pathway to document the duodenal lesions presentation; increased NO-and oxidative stress [malondialdehyde(MDA)]-levels in duodenum.RESULTS Unlike the severe course in the SAPDV-ligated controls, after BPC 157 application, the rats exhibited strong attenuation of the mucosal lesions and serosal congestion, improved vessel presentation, increased interconnections, increased branching by more than 60% from the initial value, the IAPDV and SMV were not congested. Interestingly, after 5 min and 30 min of L-NAME and L-arginine treatment alone, decreased mucosal and serosal duodenal lesions were observed; their effect was worsened at 24 h, and no effect on the collateral vessels and branching was seen. Together, L-NAME+L-arginine antagonized each other's response, and thus, there was an NO-related effect. With BPC 157, all SAPDV-ligated rats receiving L-NAME and/or L-arginine appeared similar to the rats treated with BPC 157 alone. Also, BPC 157 in SAPDV-ligated rats normalized levels of NO and MDA, two oxidative stress markers, in duodenal tissues.CONCLUSION BPC 157, rapidly bypassing occlusion, rescued the original duodenal flow through IAPDV to SMV flow, aneffect related to the NO system and reduction of free radical formation.  相似文献   
39.

Objective

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) causes multiple endocrine deficiencies, oral candidiasis and different forms of ectodermal dystrophy including enamel hypoplasia, documented in permanent teeth. Our purpose was to examine dental aberrations associated with APECED, including possible manifestations in primary teeth.

Design

We studied clinically, radiographically, and by scanning electron microscopy (SEM) teeth of children belonging to two APECED families with different mutations in the AIRE gene.

Results

In addition to enamel defects in the permanent teeth we observed hypoplastic pits and hypomaturated patches in the deciduous teeth with underlying changes in the prismatic ultrastructure. The enamel of the permanent molars exhibited a layered arrangement with included whirl-like formations.

Conclusions

Our findings confirm that APECED causes enamel defects that are individually but chronologically distributed, and can alter enamel development early enough to affect deciduous teeth.  相似文献   
40.
Asthma is the most common chronic disease in childhood characterized by chronic bronchial inflammation of variable intensity accompanied by spontaneous or drug reversible airflow obstruction. The onset of asthma, clinical presentation and response to therapy are influenced by numerous genetic and environmental factors. Asthma in childhood is characterized by its heterogeneity in terms of possible etiology, degree of inflammation and airway obstruction, lung function as well as the natural course of disease that may persist and continue to adulthood. Protective factors linked to early life experiences have also been delineated which may impact the development of asthma. Pathophysiological mechanisms of allergic reaction as an excessive inflammation driven by T-helper-2 (Th2) immunity, offer poor understanding of the heterogeneity of clinical disease. A recently introduced approach defines asthma as a syndrome that comprises of several subtypes or endotypes based on entirely novel pathways to disease. Timely diagnosis and adequate treatment are necessary to prevent irreversible airway remodeling and consequent decrease in pulmonary function.  相似文献   
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