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1.
Variations of the medial and inferior choanal limits may facilitate snoring. These are: 1) short vomer without crista choanalis vomeris and adaptational formations, 2) extremely concave posterior margin of the hard palate leading to disproportion between the muscular and aponeurotic part of m. tensor veli palatini and hence to a flabby soft palate especially during sleep, and 3) neonatal relation of the height and width of the choane resulting in a very large choanal region instead of relative reduction of choanal width compared to its increasing height. All these variations result in a flabby soft palate especially during sleep and may lead to formation of whirles of inspired air and snoring.  相似文献   
2.
Met-enkephalin (MENK) increased superoxide anion release by human polymorphonuclear cells (PMNs) at a physiological (10(-10) M) concentration and decreased release at a relatively high (10(-8) M) concentration. Surprisingly, naloxone (NAL), used as a specific antagonist in these experiments, displayed immunomodulatory actions of its own, increasing superoxide anion release at 10(-10) and 10(-8) M concentrations. Although both were effective, the dose-response curves were different for NAL and MENK. NAL and MENK also had a combined influence on O2- release. The stimulative effect of 10(-10) M MENK could be abolished by 10(-8) M NAL in seven of eight cases. Unexpectedly, the stimulatory effect of 10(-8) and 10(-10) M NAL could be abrogated by MENK in five of eight cases as well. The fact that NAL and MENK mutually interfere with one another in their effect upon O2- release by human PMNs discredits NAL as an appropriate antagonist in this system.  相似文献   
3.
Acetabular fractures represent a complex variety that are classified in different types. Conventional radiology is often inadequate to demonstrate and classify the fractures. Computed tomography (CT) has already been shown to be superior in this field. A further advantage of CT is represented by the recent availability of three-dimensional (3D) images that are realized from axial CT scans by means of a new software. The Authors report the applications of this new software to the study of the normal acetabulum and in patients with fractures. 3D images allows an effective demonstration of the fracture, its irradiation and the dislocation of bone fragments. The information is contained in one or few images rather than many axial images. Therefore the role of 3D images may be considered complementary to axial CT scans.  相似文献   
4.
The present ultrastructural investigation into osteocyte dendrogenesis represents a continuation of a previous study (Ferretti et al., Anat. Embryol., 2002; 206:21-29), in which we pointed out that, during intramembranous ossification, the well-known dynamic bone formation (DBF), performed by migrating osteoblast laminae, is preceded by static bone formation (SBF), in which cords of stationary osteoblasts transform into osteocytes in the same site where they differentiated. The research was carried out on the perichondral center of ossification surrounding the mid shaft level of various long bones of chick embryos and newborn rabbits. Transmission electron microscope observations showed that the formation of osteocyte dendrites is quite different in the two types of osteogenesis, mainly depending on whether or not osteoblast movement occurs. In DBF, osteoblasts transform into small ovoidal/ellipsoidal osteocytes and their dendrites form in an asynchronous and asymmetrical manner in concomitance with, and depending on, the advancing mineralizing surface and the receding osteogenic laminae. In SBF, stationary osteoblasts give rise to big globous osteocytes, located inside confluent lacunae, with short and symmetrical dendrites that can radiate simultaneously all around their cell body because they are completely surrounded by unmineralized matrix. Contacts and gap junctions were observed between all osteocytes (both SBF- and DBF-derived) and between osteocytes and osteoblasts. Finally, a continuous osteocyte network extends throughout the bone, regardless of its static or dynamic origin. This network has the characteristic of a functional syncytium, potentially capable of modulating, by wiring transmission, the cells of the osteogenic lineage covering the bone surfaces.  相似文献   
5.
Age- and sex-associated differences in lipid peroxidation (LPO), and total sialic acid content (TSA) in response to abuse of drugs have been reported both in humans and experimental animals. However, no data on the influence of gender and age on these parameters have been reported for methionine-enkephalin (MENK). In this study we examined the influence of age and gender on MENK-induced LPO levels in the liver and TSA content in splenocytes of CBA mice. LPO production, which was age- and gender-associated was differentially regulated by MENK at a dose of 10 mg or 2.5 mg/kg body weight. At the higher dose, MENK stimulated LPO production in younger males and females but suppressed only in older male mice. At the lower dose, MENK induced strong suppression in males while being without any effect in females. In TSA levels, the age-associated increase was greater in males and much lower in females, with higher TSA levels in younger (2.5, 4.5 months) and decreased levels in older female mice (9 months) being observed. Contrary to the effect on LPO level, TSA level in MENK-treated mice was suppressed in both sexes but only in young 2.5-month-old mice. These data provide evidence that some immunomodulatory properties of MENK are age- and gender-associated which may be relevant to the potential use of MENK as adjuvant therapy in patients with immunocompromised status.  相似文献   
6.
Cerebrospinal fluid (CSF) cytology provides valuable diagnostic and prognostic information for diseases of the central nervous system (CNS) and remains the gold standard for the detection of neoplastic meningitis. Metastatic involvement of the CSF by non‐CNS neoplasms far surpasses that of primary brain tumors, although conventional glioblastoma multiforme (GBM) can occasionally be identified in the CSF. GBM with epithelial differentiation is an uncommon variant that may contain features such as adenoid structures, signet ring cells, or squamous metaplasia. Herein, we present a case of GBM with epithelial differentiation to highlight a potential diagnostic pitfall in CSF cytology. A 55‐year‐old man presented with neurological symptoms and a 6.4 cm left temporal lobe cystic mass. Primary resection revealed GBM with focal epithelial differentiation confirmed by cytokeratin, epithelial membrane antigen, and glial fibrillary acidic protein immunohistochemical studies. Four months following primary resection, the patient developed severe headache for which a lumbar puncture with CSF cytologic evaluation was performed. The cytospin preparation showed numerous malignant epithelioid cells with high nuclear–cytoplasmic ratio and prominent cytoplasmic vacuoles resembling metastatic carcinoma. However, the lesional cells were cytomorphologically identical to the epithelial component present in the patient's recently diagnosed GBM. This case illustrates the potential for GBM with epithelial differentiation to closely mimic metastatic carcinoma from a non‐CNS site in CSF cytology, which expands the differential diagnosis and emphasizes the necessity of clinical correlation. Diagn. Cytopathol. 2015;43:638–641. © 2015 Wiley Periodicals, Inc.  相似文献   
7.
Several implant surface debridement methods have been reported for the treatment of peri-implantitis, however, some of them can damage the implant surface or promote bacterial resistance. Photodynamic therapy (PDT) is a new treatment option for peri-implantitis. The aim of this in vitro study was to analyze implant surface decontamination by means of PDT. Sixty implants were equally distributed (n?=?10) into four groups and two subgroups. In group G1 there was no decontamination, while in G2 decontamination was performed with chlorhexidine. G3 (PDT???laser?+?dye) and G4 (laser, without dye) were divided into two subgroups each; with PDT performed for 3 min in G3a and G4a, and for 5 min in G3b and G4b. After 5 min in contact with methylene blue dye (G3), the implants were irradiated (G3 and G4) with a low-level laser (GaAlAs, 660 nm, 30 mW) for 3 or 5 min (7.2 and 12 J). After the dilutions, culture media were kept in an anaerobic atmosphere for 1 week, and then colony forming units were counted. There was a significant difference (p?<?0.001) between G1 and the other groups, and between G4 in comparison with G2 and G3. Better decontamination was obtained in G2 and G3, with no statistically significant difference between them. The results of this study suggest that photodynamic therapy can be considered an efficient method for reducing bacteria on implant surfaces, whereas laser irradiation without dye was less efficient than PDT.  相似文献   
8.
The first genotype‐phenotype relationship in breast pathology developed in 1994 with the discovery of the CDH1 gene. This finding eventually provided biological insight into the characteristic morphology of invasive lobular carcinoma. Subsequent investigative efforts have uncovered additional molecular alterations largely responsible for the histology of several breast neoplasms including secretory carcinoma, adenoid cystic carcinoma, tall cell carcinoma with reversed polarity, fibroepithelial lesions, and most recently, adenomyoepithelioma. Evaluation of the genomic landscape of other special types of breast cancer with distinctive growth patterns, such as invasive mucinous carcinoma, have yet to uncover recurring cytogenetic and/or molecular alterations. Despite the lack of a hallmark alteration in mucinous carcinoma, it is important to note the relative decrease in PIK3CA mutations compared with invasive carcinoma of no special type. In this review, we describe the clinical and pathologic features of breast tumors with recognized genotype‐phenotype correlations and summarize the molecular alterations of mucinous carcinoma.  相似文献   
9.
Recurrent herpes labialis is a worldwide life-long oral health problem that remains unsolved. It affects approximately one third of the world population and causes frequent pain and discomfort episodes, as well as social restriction due to its compromise of esthetic features. In addition, the available antiviral drugs have not been successful in completely eliminating the virus and its recurrence. Currently, different kinds of laser treatment and different protocols have been proposed for the management of recurrent herpes labialis. Therefore, the aim of the present article was to review the literature regarding the effects of laser irradiation on recurrent herpes labialis and to identify the indications and most successful clinical protocols. The literature was searched with the aim of identifying the effects on healing time, pain relief, duration of viral shedding, viral inactivation, and interval of recurrence. According to the literature, none of the laser treatment modalities is able to completely eliminate the virus and its recurrence. However, laser phototherapy appears to strongly decrease pain and the interval of recurrences without causing any side effects. Photodynamic therapy can be helpful in reducing viral titer in the vesicle phase, and high-power lasers may be useful to drain vesicles. The main advantages of the laser treatment appear to be the absence of side effects and drug interactions, which are especially helpful for older and immunocompromised patients. Although these results indicate a potential beneficial use for lasers in the management of recurrent herpes labialis, they are based on limited published clinical trials and case reports. The literature still lacks double-blind controlled clinical trials verifying these effects and such trials should be the focus of future research.  相似文献   
10.

Purpose

We conducted a retrospective study to evaluate the influence of different tumor enhancement measurement approaches on the ability of computed tomography (CT) to differentiate between solid forms of clear cell renal cell carcinoma (RCC), other RCC histologic subtypes and oncocytomas. Different RCC subtypes have a diverse range of malignant potential; consequently, the information about RCC subtype obtained using minimally invasive imaging method before the treatment could allow the more accurate therapy planning. Differentiation of ccRCCs from oncocytomas is important because oncocytomas are usually benign tumors which could be treated conservatively.

Methods

CT images of 113 patients with 118 solid renal tumors were evaluated. The imaging protocol consisted pre-contrast and post-contrast images during the arterial and nephrographic phases. Renal tumor attenuation values were measured using region of interest covering as much of the solid enhancing tumor tissue as possible. Tumor attenuation values and tumor enhancement ratios were correlated with histologic subtype. One hundred of tumors were diagnosed as clear cell RCC, nine as non-clear cell RCC and nine as oncocytoma.

Results

Tumor attenuation values of >74 HU on the arterial phase scans significantly correlated with clear cell RCC (Az 0.73). The tumor-to-aorta enhancement ratios calculated on tumor attenuation values measured on the arterial phase scans had a cutoff value of >0.29, which significantly correlated with clear cell RCC (Az 0.79). All ROC curves for differentiating the clear cell RCC from oncocytomas have area under the curve too small (0.5 or less) to have chose cutoff value with sensitivity and specificity that could be applied in clinical work.

Conclusion

Enhancement measurements of renal carcinomas on CT images in the arterial phase can be used as an auxiliary method in the pretreatment differentiation of solid forms of the most frequent RCC subtypes in patients not suitable for core biopsy but who are suitable for minimally invasive treatment methods and/or targeted therapy.  相似文献   
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