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1.
Cancer stem cells are thought to be closely related to tumor progression and recurrence, making them attractive therapeutic targets. Stem cells of various tissues exist within niches maintaining their stemness. Glioblastoma stem cells (GSCs) are located at tumor capillaries and the perivascular niche, which are considered to have an important role in maintaining GSCs. There were some extracellular matrices (ECM) on the perivascular connective tissue, including type 1 collagen. We here evaluated whether type 1 collagen has a potential niche for GSCs. Imunohistochemical staining of type 1 collagen and CD133, one of the GSCs markers, on glioblastoma (GBM) tissues showed CD133‐positive cells were located in immediate proximity to type 1 collagen around tumor vessels. We cultured human GBM cell lines, U87MG and GBM cells obtained from fresh surgical tissues, T472 and T555, with serum‐containing medium (SCM) or serum‐free medium with some growth factors (SFM) and in non‐coated (Non‐coat) or type 1 collagen‐coated plates (Col). The RNA expression levels of CD133 and Nestin as stem cell markers in each condition were examined. The Col condition not only with SFM but SCM made GBM cells more enhanced in RNA expression of CD133, compared to Non‐coat/SCM. Semi‐quantitative measurement of CD133‐positive cells by immunocytochemistry showed a statistically significant increase of CD133‐positive cells in Col/SFM. In addition, T472 cell line cultured in the Col/SFM had capabilities of sphere formation and tumorigenesis. Type 1 collagen was found in the perivascular area and showed a possibility to maintain GSCs. These findings suggest that type 1 collagen could be one important niche component for CD133‐positive GSCs and maintain GSCs in adherent culture.  相似文献   
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Extraskeletal osteosarcoma is an uncommon malignant neoplasm. The origin of osteosarcoma in the pleura is extremely rare, with only four such cases so far documented in the literature to the best of our knowledge. We herein report the case of a 64-year-old Japanese man in whom a left pneumonectomy and pleurectomy were carried out to remove a huge tumor. The pathological examination confi rmed a diagnosis of chondroblastic osteosarcoma that had originally arisen from the pleura.  相似文献   
4.
Carney complex is a rare autosomal-dominant, familial tumor syndrome first described in the mid 80's. This syndrome is multiple neoplasia syndrome featuring cardiac, endocrine, cutaneous, and neural tumor, in addition to a variety of pigmented lesions of the skin and mucosa. We report the case of a 12-year-old female patient with Carney complex who manifested a high value of serum growth hormone (s-GH), cutaneous angiomyxomas and labial pigmented lesions. Magnetic resonance imaging (MRI) revealed a cystic pituitary tumor. We carried out removal of the pituitary tumor via the transsphenoidal approach. In addition to the pituitary adenoma, pathological examination revealed the presence of a Rathke cleft cyst. So far, approximately 500 cases of this disorder have been described, but there have been no cases similar to our case described here. Therefore, the present case seems to be the first case of Carney Complex complicated with pituitary adenoma and Rathke cleft cyst.  相似文献   
5.
Recently, apoptosis has been implicated in the selective neuronal loss of Alzheimer's disease (AD). Apoptosis is regulated by the B cell leukemia-2 gene product (Bcl-2) family (Bcl-2, Bcl-x, Bax, Bak and Bad) and the caspase family (ICH-1 and CPP32), with apoptosis being prevented by Bcl-2 and Bcl-x, and promoted by Bax, Bak, Bad, ICH-1 and CPP32. In the present study, we examined the levels of these proteins in the membranous and cytosolic fractions of temporal cortex in AD and control brain. In the membranous fraction, the levels of Bcl-2, Bcl-xL, Bcl-xβ, Bak and Bad were increased in AD. In the cytosolic fractions, the level of Bcl-xβ was increased, while Bcl-xL, Bax, Bak, Bad and ICH-1L were unchanged. CPP32 was not detected in AD or control brain. These findings demonstrate a differential involvement of cell death-regulatory proteins in AD and suggest that Bak, Bad, Bcl-2 and Bcl-x are upregulated in AD brains.  相似文献   
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We are reporting a case of a rare renal actinomycosis in a 12-year-old mentally-retarded girl. Proteinuria and hemopyuria were pointed out one year before the operation by an annual medical check-up and IVP subsequently performed showed foreign bodies at the upper pole of the right kidney. The patient continued to have pyuria and right nephrectomy was performed. There was a fistula between the duodenum and the upper portion of the right kidney. Foreign bodies (two bobby pins) were found in the kidney. Subsequent pathologic examination of the resected kidney revealed an actinomycotic lesion.  相似文献   
7.
One-stage frontofacial monobloc advancement has been used to treat patients with craniofacial synostosis including Crouzon disease. Nishimoto et al. first applied a rigid external distraction system for two patients. However, precise surgical techniques and proper indication for this gradual distraction method have not yet been established. This report describes the advantages and detailed surgical methods of frontofacial monobloc advancement using a Rigid External Distraction (RED- II) System. Three patients with severe craniofacial synostosis including Crouzon disease and Treacher Collins syndrome were treated. The ages of patients were 9, 9, and 8 year old, respectively. The RED- II System was safely applied for these young children and cosmetic results were sufficient. No major postoperative complications occurred.  相似文献   
8.
Peroxisomes (microbodies) are ubiquitous single-membrane–bounded organelles and fulfill essential roles in the cellular metabolism. They are found in virtually all eukaryotic cells and basically multiply by division. However, the mechanochemical machinery involved in peroxisome division remains elusive. Here, we first identified the peroxisome-dividing (POD) machinery. We isolated the POD machinery from Cyanidioschyzon merolae, a unicellular red alga containing a single peroxisome. Peroxisomal division in C. merolae can be highly synchronized by light/dark cycles and the microtubule-disrupting agent oryzalin. By proteomic analysis based on the complete genome sequence of C. merolae, we identified a dynamin-related protein 3 (DRP3) ortholog, CmDnm1 (Dnm1), that predominantly accumulated with catalase in the dividing-peroxisome fraction. Immunofluorescence microscopy demonstrated that Dnm1 formed a ring at the division site of the peroxisome. The outlines of the isolated dynamin rings were dimly observed by phase-contrast microscopy and clearly stained for Dnm1. Electron microscopy revealed that the POD machinery was formed at the cytoplasmic side of the equator. Immunoelectron microscopy showed that the POD machinery consisted of an outer dynamin-based ring and an inner filamentous ring. Down-regulation of Dnm1 impaired peroxisomal division. Surprisingly, the same Dnm1 serially controlled peroxisomal division after mitochondrial division. Because genetic deficiencies of Dnm1 orthologs in multiperoxisomal organisms inhibited both mitochondrial and peroxisomal proliferation, it is thought that peroxisomal division by contraction of a dynamin-based machinery is universal among eukaryotes. These findings are useful for understanding the fundamental systems in eukaryotic cells.Peroxisomes are single-membrane–bounded organelles found in nearly all eukaryotic cells. In plant cells, peroxisomes are involved in a variety of metabolic pathways essential for development associated with photorespiration, lipid mobilization, and hormone biosynthesis (1, 2). In animals, abnormalities in peroxisome proliferation are associated with carcinogenesis, neurodegeneration, and cerebrohepatorenal syndrome (1, 3). Peroxisomes are thought to basically proliferate by division, although they do not contain DNA (1). Because the cells of multiperoxisomal organisms, such as yeasts, plants, and animals, contain irregularly shaped peroxisomes that divide randomly, their proliferation has been examined by analyzing peroxisome abundance and distribution (4, 5). Therefore, the division machinery (ring) that is essential for proliferation and plays a central role is unclear. Cyanidioschyzon merolae offers unique advantages for studying peroxisomal division, because each cell contains a minimal set of basic eukaryotic organelles, comprising one chloroplast, one mitochondrion, one cell nucleus, and one peroxisome, the divisions of which occur in that order and can be synchronized by light/dark cycles (69) (Fig. 1 A and B and Fig. S1). In C. merolae, peroxisomes do not form de novo from the endoplasmic reticulum in the peroxisomal division cycle but divide by binary fission (6, 7, 10). In addition, the complete sequence of the genome has enabled proteomic analyses (7, 11).Open in a separate windowFig. 1.Identification of Dnm1 from the dividing-peroxisome fraction. (A) Immunofluorescence and schematic images of mitochondrial and peroxisomal divisions of C. merolae. Peroxisomal (red) division occurred after mitochondrial (yellow) division. Chl, chloroplast; Mt, mitochondrion; Nu, nucleus; PC, phase-contrast image; Po, peroxisome. (B) Frequencies of dividing cell nuclei (Nu), dividing chloroplasts (Chl), dividing mitochondria (Mt), and dividing peroxisomes (Po) in non–oryzalin-treated cells (control) and oryzalin-treated cells (Orz+) at the indicated times after synchronization (n > 100). (C) Proteomic analysis of peroxisomal fractions in control and oryzalin-treated cells at 20 h after synchronization. The major bands specific to oryzalin-treated cells were identified as catalase (black arrowhead), Dnm1 (red arrowhead), and others. (D) Immunoblot analyses of Dnm1, catalase, mitochondria division protein (Mda1), porin, and chloroplast division protein (PDR1). Cell, whole cell; Mt/Chl, isolated mitochondria and chloroplast; Po, isolated peroxisomes. (Scale bars: 1 μm.)  相似文献   
9.
Gastric emptying is achieved by co-operation between gastric and duodenal motor activity. Therefore, evaluation of gastric emptying and its associated mechanisms would benefit clinical therapy as well as medical research. Healthy volunteers underwent rapid magnetic resonance imaging (MRI) of the abdomen along the coronal plane after ingestion of a liquid meal. The gastric fundal and duodenal areas were quantified semi-automatically by self-developed segment software. The average gastric fundal area determined by the serosal end in 40 sequential images was reduced to ~81% 30 min after and to ~70% 60 min after ingestion of a liquid meal. The average duodenal area also decreased to ~86% after 30 min and to 83% after 60 min. In contrast, changes in the centre of gravity increased to about fivefold after 30 min and to about threefold after 60 min. The mean velocity of the duodenal wall mimicked changes in the centre of gravity. The application of metoclopramide, a dopamine D(2) receptor antagonist, accelerated gastric emptying, presumably due to facilitated duodenal activity even immediately after liquid meal ingestion. The ingestion of water caused fast gastric emptying in 30 min, accompanied by high duodenal motility, but it ceased after 60 min, presumably reflecting complete gastric emptying. A rapid MRI scan visualized the association between gastric emptying and duodenal motility that could be modified by calories and dopaminergic neurotransmission. Changes in the centre of gravity and mean velocity of the duodenal wall appear to quantify the motility obtained from cine MRI accurately.  相似文献   
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