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1.
This paper deals with digital radiological image processing, with a special emphasis on quantitative measurement extraction aimed at discriminating different lung pathologies. Texture analysis of these images, not easily performed by the human eye, can be carried out by means of fractal techniques, which allow different textures to be characterized by a single parameter--i.e. the fractal dimension. To extract the fractal dimension of an image, the so-called "blanket" method is employed, which allows the average fractal dimension of an image area to be evaluated. The result of this processing is a new image whose points are assigned the average fractal dimension value of the area they belong to. The behaviors of fractal dimension histograms related to various simulations of lung pathologies are notably different, which allows such pathologies to be effectively characterized and differentiated on a quantitative basis. The radiographic images the "blanket" method was applied to are related to simulations of both pathological and healthy tissues. The behaviors of fractal dimension histograms and the average fractal dimension values allow the characterization of the different pathologies both for single tissues and in case of superimposition of a healthy tissue on a pathological one. The promising simulation results have encouraged us to carry out the present experimental investigation in the field of lung neoplasms.  相似文献   
2.
Black organic coatings and ritual deposits on ancient Egyptian coffins and cartonnage cases are important and understudied sources of evidence about the rituals of funerary practice. Sometimes, the coatings were applied extensively over the surface of the coffin, resembling paint; in other cases, they were poured over the mummy case or wrapped body, presumably as part of a funerary ritual. For this study, multiple samples of black coatings and ritual liquids were taken from 20 Egyptian funerary items dating to a specific time period (c. 943 to 716 BC). Multiple sampling from each object enabled several comparisons to be made: the variability of the black coating within one application, the variability between two applications on one object, and the variability from object to object. All samples were analyzed for lipids using gas chromatography–mass spectrometry (GC-MS), and 51 samples from across the 20 items were further analyzed for the presence of bitumen using solid phase separation followed by selected ion monitoring GC-MS. The majority of the black substances were found to comprise a complex mixture of organic materials, including bitumen from the Dead Sea, conifer resin, and Pistacia resin, providing evidence for a continuation in international trade between Egypt and the eastern Mediterranean after the Late Bronze Age. Both the coating and the anointing liquid are very similar to mummification balms, pointing to parallels with Egyptian embalming rituals and raising questions about the practical aspects of Egyptian funerary practice.

To the ancient Egyptians, black symbolized the underworld and Osiris (often shown with black skin) and also night, especially when used in contrast with yellow and gold (for the sun) and the rich black soil of fertility and regeneration (13). The practice of using black coatings on Egyptian coffins is first attested in the Middle Kingdom (e.g., the cartonnage cases of Nepthys and Hapiankhtifi, Metropolitan Museum of Art 11.150.15 and 12.183.11c.1-0.2) and occurs in the New Kingdom, when black coatings are also used on funerary objects such as divine figures, shabtis, and shabti boxes (35). A secondary application of a black anointing liquid in a funerary context is known from at least as early as the burial of Tjuyu (18th Dynasty, c. 1375 BC), whose gilded funerary mask was anointed with black fluid (6).The application of black substances as coatings and anointing liquids on coffins and mummy cases also occurs in the Third Intermediate Period c. 1086 to 664 BC. This period in Egypt was a time of decentralized rule. In its first phase (21st Dynasty c. 1086 to 943 BC), kings based in the eastern Delta ruled the northern part of Egypt, sharing power with a line of generals, who also acted as high priests of Amun at Thebes, and controlled the southern stretch of the Nile valley. A return to centralized administration in the early 22nd Dynasty (c. 943 to 716 BC) was followed by a gradual fragmentation of the country into smaller political units, some of which were ruled by individuals claiming kingly status, while others were controlled by rulers of Libyan chiefdoms (7), thus Dynasties 22 to 24 and the early 25th Dynasty overlap. The end of the Bronze Age had seen catastrophic events across the eastern Mediterranean, with the Mycenaean and Hittite states collapsing (8, 9). Egypt itself saw incursions and lost control of land in Syria Palestine. Evidence from Egypt and the Levant during this time suggests fluctuating levels of contact and influence (10).During this period, burial practices were changing; instead of a decorated tomb and a wide array of tomb goods, the focus turned toward the body and the coffin (11, 12). The elite continued to lavish expenditure on their burials, but due to high levels of tomb raiding and tomb and coffin appropriation, emphasis was no longer placed on the funerary goods placed in the tomb, as was common in the New Kingdom (13). Instead, the expenditure was concentrated on the body and the coffin, which could be moved to a more secure location if necessary. The 21st Dynasty saw developments in mummification that indicate an increase in the resources allocated for those procedures (14). In the 22nd Dynasty, further changes in the treatment of the body were introduced, most notably the introduction of the cartonnage case, into which the mummy was tightly laced (3). Cartonnage is made with layers of linen, plaster, and glue, similar to papier maché, which can be molded to shape and which dries to make a hard case. These cases were valuable in terms of a vehicle for display as they could be highly decorated and gilded (14), and cartonnage is much more difficult to repurpose than other funerary goods because the body of the deceased is sewn inside. Concentrating resources into the preparation of the body, mummy case, and coffin allowed the elite to display their wealth and power while at the same time securing their investment.Black substances painted on the inside and/or outside of coffins and other funerary items or poured over cartonnage as part of the funerary ritual are a material source of evidence for examining the resourcing of funerary activities during this time of political upheaval. A research project on the 22nd-Dynasty coffins, cartonnage mummy cases, shabti boxes, and Osiris figures in the collection of the British Museum offered the opportunity to address this subject. Using analytical chemistry to examine the complex molecular composition of the black ritual substances, the study aimed to identify the materials used and their likely sources. Determination of chemical composition also offered a means to investigate how the materials were processed and applied as well as patterns of use within the funerary context.Previous research on similar materials has been limited and varied in terms of analytical techniques, covering multiple time periods and considering ritual applications alongside mummification balms (15, 16) or considering a small subset of samples (5, 1719).* By focusing on burial goods of the 22nd Dynasty, this research is a more targeted examination of funerary ritual residues than has been previously undertaken.  相似文献   
3.

Objectives

Implant rehabilitation in oral lichen planus (OLP) is a major challenge for clinicians and patients. There is limited scientific evidence, primarily case reports and small case series. We conducted a literature review of data on the effectiveness and safety of implant rehabilitation in OLP patients.

Material and methods

We searched MEDLINE, Embase and Cochrane databases for articles on implant placement in OLP patients (searches from 1980 to 2011).

Results

Eight studies (41 OLP patients rehabilitated with 135 implants) met the inclusion criteria. Survival rate of implants was 94.8% over a mean follow-up of 56.5?months.

Conclusions

There is very limited evidence on the safety and benefits of implant placement in OLP patients. Implant loss appears not to be directly related to OLP, but linked to factors such as parafunctions, poor bone quality and marginal mandibular resection. The benefits and harms of using implants in people with OLP require thorough evaluation in properly designed randomised, controlled studies.

Clinical relevance

OLP is not an absolute contraindication for implant insertion and there is no increased risk of failure. Implants should be positioned only if mucosal signs and symptoms are in the remission phase. A careful oral hygiene and frequent follow-up are the main recommendations in OLP patients rehabilitated with implants.  相似文献   
4.
Standardized nonopioid preoperative protocol effects perioperative opioids. Combined use of acetaminophen, pregabalin, celecoxib, and transdermal scopolamine (APCS), in mastectomy with immediate subpectoral reconstruction procedures. Retrospective (2014‐2017) cohort study (n = 305) examined treatment groups; APCS, no treatment (NONE), and partial combination APCS (OTHER), employing multivariable gamma regression models controlling preoperative and perioperative variables, examining postoperative opioid use (oral morphine equivalents, OME) and hospital stay (hours, LOS). APCS group had a 25% statistical reduction in OME total vs OTHER, a 12% statistical reduction in LOS vs OTHER, and 11% statistical reduction in LOS vs NONE. Standardized nonopioid preoperative protocol provides insight into perioperative opioid use.  相似文献   
5.
The aim is to establish the feasibility to image in vivo microscopic dental surface by non-invasive, real-time, en face Reflectance Confocal Microscopy (RCM). Fifteen healthy volunteers referred at the Multidisciplinary Department of Medical-Surgical and Odontostomatological Specialties, Second University of Naples, Naples, Italy, were enrolled. A commercially available hand-held RCM (Vivascope®3000, Lucid, Rochester, NY, USA) was used to image in vivo the dental surface of the upper right and left central incisors of each volunteer. Totally, thirty vestibular surfaces of upper central incisors were imaged in vivo by RCM to preliminary image the dental surface and assess the feasibility of a more extended study on teeth. In vivo RCM was able to image the dental surface within the enamel, at a maximum depth imaging of 300 μm, with images good in quality and the capability to detect enamel structures such as enamel lamellae and enamel damages, such as unevenness and cracks. In conclusion, enamel “optical biopsy”, gained by RCM imaging, revealed to be a non-invasive real-time tool valid to obtain architectural details of the dental surface with no need for extraction or processing the samples. RCM appears to be an optimum auxiliary device for investigating the architectural pattern of superficial enamel, therefore inviting further experiments aimed to define our knowledge about damages after etching treatments or bracket removal and the responsiveness to fluoride seals and the morphology of the tooth/restoration interface. Moreover, this device could also be used to detect relevant diseases like caries, or to assess surface properties to evaluate lesion activity.  相似文献   
6.
The mechanisms employed by human papillomaviruses (HPVs) to control the replication of the viral genome and the expression of the viral genes are extremely complex and further complicated by the fact that the viral life cycle is intricately tied to the differentiation program of its host epithelial tissue. Indeed, HPV-induced immortalization of keratinocytes and disruption of the normal cytokeratin (CK) expression pattern progress pari passu during the stepwise process that preludes to squamous cell carcinoma. In our study, we have analyzed the interaction occurring between HPV type 16 E7 mRNA and the intermediate cytokeratin filaments 7 and 19 and report data in favor of a possible association between HPV16 E7 protein level and CK19.  相似文献   
7.
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9.
OBJECTIVES: To investigate the effects of aldosterone receptor blockade in postinfarction heart failure. METHODS: Eighty-seven rats with moderate myocardial infarction were randomized to receive either no drug or canrenone, the active metabolite of spironolactone, 20 mg/kg/day, or ramipril, 1 mg/kg/day, or a combination of the two drugs. Treatment was initiated 1 month after coronary ligation and lasted 4 weeks. Echocardiography was performed at baseline and after 4 weeks. LV catheterization, isolated heart studies, morphometric histology, myocardial norepinephrine and SERCA-2 mRNA were assessed at the end of the treatment period. RESULTS: Infarct sizes were 33+/-3, 32+/-3, 34+/-3, and 34+/-4% in the placebo, canrenone, ramipril, and combination groups, respectively. Canrenone attenuated LV remodeling, improved LV systolic and diastolic function, and markedly reduced interstitial and perivascular fibrosis. These effects were increased by concomitant ramipril therapy. Moreover, myocardial norepinephrine content was decreased while ventricular fibrillation threshold significantly augmented by canrenone. SERCA-2 levels remained unchanged. CONCLUSIONS: Canrenone attenuated LV dilation and interstitial remodeling, and improved LV filling dynamics and systolic function in the rat model of postinfarction heart failure. Addition of ramipril conferred further cardioprotection. Canrenone also reduced myocardial norepinephrine content and increased ventricular fibrillation threshold. The data provide a potential explanation for the decreased sudden death observed in the RALES study.The mechanisms of action of aldosterone inhibition are still poorly understood, despite its proven efficacy in heart failure. Rats with postinfarction heart failure were randomized to receive for 1 month either no drug or canrenone, or ramipril, or a combination of canrenone and ramipril. Canrenone treatment was associated with a significant attenuation of LV dilation, better LV diastolic and systolic dynamics, and a marked reduction of reactive fibrosis. These effects were enhanced by concomitant ramipril therapy. Moreover, canrenone increased ventricular fibrillation threshold and reduced myocardial norepinephrine content. The data may explain the reduced mortality demonstrated by the RALES.  相似文献   
10.
Squamous cell carcinoma (SSC) is the most frequent malignant tumor of the oral cavity. A study on the effect of all-trans retinoic acid (RA) on cell growth, expression of GRIM-19 and content and activity of complex I of the mitochondrial respiratory chain in normal human keratinocytes (NHEK) and mouth carcinoma cells with low (HN) and high (KB) transformation grade was carried out. In NHEK cells, RA treatment resulted in growth suppression, significant overexpression of GRIM-19 protein, enhanced content of complex I but depressed activity of NADH-UQ oxidoreductase activity of the complex. In HN cells, RA treatment depressed cell growth, inhibited the enzymatic activity of complex I but had no significant effect on the levels of GRIM-19 and complex I. In KB cells RA had no effect on cell growth, GRIM-19 expression, content and activity of complex I.  相似文献   
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