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1.
Purpose Reelin is important in the guidance of neuronal stem cells in the central nervous system during normal development. We wished to determine whether reelin is expressed in the retina and cornea after injury. Methods Mice underwent laceration of their retina as well as corneal epithelial debridement. The mice were sacrificed at 3 days, and eyes were fixed and stained for reelin expression and reelin messenger ribonucleic acid (mRNA). Results In normal eyes, reelin was expressed only at very low levels in the ganglion cell layer of the retina and the endothelial cell layer of the cornea. In injured eyes, there was marked expression in reelin immunoreactivity in the retina and cornea. Reelin gene expression was seen in the retina and cornea. Conclusions Reelin is expressed during normal retinogenesis. This study shows that reelin is also upregulated following injury to the retina and cornea. The expression of reelin following injury suggests that reelin may play an important role in regulating stem cell trafficking in neuronal and nonneuronal tissues following injury similar to its role in normal organogenesis. For consideration of publication in Graefe’s Archive for Clinical and Experimental Ophthalmology.  相似文献   
2.
Oral Diseases (2012) 18 , 206–212 Objectives: The effect of growth differentiation factor 5 and bone morphogenetic protein 2 on human periodontal ligament‐derived cells was investigated with special reference to tendo/ligamentogenesis‐related markers. Materials and Methods: Effects of each factor were analyzed by quantitative PCR for scleraxis and tenomodulin and by western blotting for scleraxis. After exposure to those factors, STRO‐1‐positive and STRO‐1‐negative fractions of human periodontal ligament tissues were isolated with an immunomagnetic cell sorting system, and the expression of scleraxis in each fraction was analyzed by western blotting. Non‐separated crude cells were used as a control. Results: Growth differentiation factor 5 and bone morphogenetic protein 2 did not increase alkaline phosphatase activity in crude periodontal ligament‐derived cells. Growth differentiation factor 5, but not bone morphogenetic protein 2, increased the expression of scleraxis in crude, STRO‐1‐positive and STRO‐1‐negative periodontal ligament‐derived cells. The expression of scleraxis in STRO‐1‐positive periodontal ligament‐derived cells was significantly less compared to that in crude P2 and STRO‐1‐negative periodontal ligament‐derived cells. Conclusion: Growth differentiation factor 5 induced the expression of scleraxis and may enhance tendo/ligamentogenesis in human periodontal ligament‐derived cells. The expression of scleraxis was higher in STRO‐1‐negative fraction, suggesting more differentiated state of the cells.  相似文献   
3.
A 13-year-old boy was referred to us for investigation of a giant liver mass, approximately 16 cm in diameter. Sonographically guided percutaneous needle biopsy was performed and histological examination revealed a fetal-type hepatoblastoma. After four courses of chemotherapy, we performed a left hepatic trisegmentectomy. Follow-up computed tomography, 55 months after the surgery, showed a 1-cm tumor on the route of the preoperative needle biopsy. A second laparotomy revealed a peritonealised tumor, which was excised. The histology of this tumor was identical to that of the primary hepatoblastoma. To our knowledge, this is only the second report of needle tract implantation of hepatoblastoma after percutaneous needle biopsy.  相似文献   
4.

Background

The present study aimed to assess the long-term results of seton placement for fistula-in-ano (FIA) in infants.

Methods

Data of patients aged <1 year who presented to our department with perianal abscess (PA) between January 2006 and February 2010 were retrospectively reviewed. Our standard initial treatment for PA was incision and drainage. Patients with systemic diseases and inflammatory bowel diseases were excluded.

Results

Ninety-five patients were treated for PA and/or FIA during the 5-year period, and follow-up data were available for 90 patients. The mean follow-up duration in these patients was 49.8?±?11.4 months, and mean age at presentation was 3.1?±?2.7 months. Of the 90 patients, 36 (40 %) developed FIA (39 lesions) and underwent seton placement. The condition healed in a mean period of 6.3?±?4.0 weeks after the placement of a cutting seton. Healing of the fistula was achieved in 35 (97.2 %) of 36 patients after the initial seton procedure, and one patient who showed recurrence underwent a second seton placement, resulting in successful healing of the FIA after 5 weeks.

Conclusions

The long-term success of seton placement indicates that this procedure should be a treatment option for FIA in infants.  相似文献   
5.
In addition to a stimulatory effect on FSH production by the pituitary gland, activin is thought to have a paracrine or autocrine role in follicular development in the ovary, where it is produced. Recently, we established a human ovarian granulosa tumor cell line, KGN, which possesses in vivo characteristics of granulosa cells, namely the expression of functional FSH receptors and cytochrome P-450 aromatase. Here, we have demonstrated the activin signaling pathway and its role in KGN cells. A series of transient transfection experiments revealed that activin type IB receptor (ActRIB) is an essential component of the activin signaling pathway in KGN cells. Smad2 was found to act downstream of ActRIB as an intracellular signal transmitter. Smad7, but not Smad6, was an inhibitory Smad in the pathway. Finally, we show that FSH receptor expression and cytochrome P-450 (P-450) aromatase activity was up-regulated by activin stimulation through ActRIB in KGN cells. These results show that we have clarified the signaling mechanisms and the roles of activin in the human granulosa cell line, KGN. Activin signaling mediated by ActRIB-Smad2 system in the ovary may thus be essential for the regulation of follicular differentiation.  相似文献   
6.
ObjectiveThe clearance of the pharynx by deglutition and the respiratory phase patterns associated with deglutition are important in protecting airways and lungs against aspiration. The deglutition and respiratory phase patterns during sleep in patients (without swallowing disorders while awake) with obstructive sleep apnea (OSA) precipitating recurrent intractable aspiration pneumonia were investigated.MethodsAfter videoendoscopic and videofluorographic examinations of swallowing showed subjects had no swallowing disorders while awake, two adults with recurrent intractable aspiration pneumonia precipitated by severe OSA were examined via time-matched digital recordings of polysomnography and surface electromyography of the muscles (thyrohyoid and suprahyoid muscles) related to swallowing and compared with the same patients before and under CPAP therapy.ResultsCPAP therapy cured recurrent intractable aspiration pneumonia. Swallows following and/or followed by inspiration (uncoordinated deglutition with respiration), which were frequently observed before CPAP therapy, were markedly reduced under CPAP therapy. On the other hand, swallows following and/or followed by expiration (coordinated deglutition with respiration) markedly increased under CPAP therapy. Deglutition was related to the sleep stage. The deeper the sleep stage, the lower the deglutition frequency. Before and under CPAP therapy, swallowing was infrequent and absent for long periods. However, respiratory phase patterns associated with sleep-related deglutition in patients with OSA under CPAP therapy markedly improved.ConclusionsIn patients (without swallowing disorders while awake) with OSA precipitating recurrent intractable aspiration pneumonia, the high rate of uncoordinated deglutition with respiration (swallows following and/or followed by inspiration) during sleep were markedly reduced and the rate of coordinated deglutition with respiration (swallows following and/or followed by expiration) was markedly increased under CPAP therapy.Sleep-related deglutition and respiratory phase patterns are likely to adversely influence aspiration pneumonia in patients with OSA. CPAP therapy improved not only apnea-hypopnea during sleep and sleep quality but also sleep-related deglutition, especially respiratory phase patterns associated with deglutition in patients with OSA. CPAP therapy may decrease the risk of aspiration and greatly improve aspiration-related diseases such as aspiration pneumonia.  相似文献   
7.

Purpose

The presence of both systemic and airway inflammation has been suggested in obstructive sleep apnea (OSA) by increased levels of inflammatory biomarkers in the circulation and respiratory specimens. We aimed to investigate the relationship between systemic and airway inflammation in OSA.

Methods

This study was conducted by simultaneously measuring various biomarkers both in serum and induced sputum of 43 patients. We compared the relationships of these biomarker levels with polysomnographic data and obesity measurements and also investigated their interrelationships between systemic and local compartments. We also assessed the relation of inflammatory markers with proximal airway resistance measured by impulse oscillometry.

Results

In multiple regression analyses, each measured serum biomarker [leptin, interleukin-6 (IL-6), IL-8, tumor necrosis factor-α (TNF-α), and vascular endothelial growth factor (VEGF)] significantly correlated with waist circumference or fat area determined by computed tomography. In contrast, regarding airway inflammation, sputum IL-6, IL-8, TNF-α, and VEGF significantly correlated with OSA severity as indicated by the respiratory disturbance index or oxygen desaturation indices. Sputum IL-6, IL-8, TNF-α, and VEGF were significantly related to sputum neutrophil number, and sputum IL-8 and TNF-α were related to proximal airway resistance independently of body mass index. There were no significant interrelationships between the same biomarkers in serum and induced sputum.

Conclusions

Systemic and airway inflammation in OSA might be differently regulated by OSA itself and comorbid obesity, depending on the type of cytokine. Although we did not find apparent interrelationships between systemic and local compartments, further studies are needed to clarify this concept.  相似文献   
8.
AIM: We investigated the extent of apoptosis in crypt cells and Peyer's patches (PPs) during small bowel allograft rejection in rats to examine the effect of FTY720 during rejection. METHODS: Orthotopic small bowel transplantations (SBTs) were performed from BN to LEW rats. Isografted animals served as controls. Three groups of SBT animals were studied on days 3, 5, and 7 after operation: isograft, untreated allograft, allograft with FTY720. FTY720 was orally administered by gavage (1 mg/kg/d) to allograft recipients on 7 consecutive days. Cryostat sections were prepared from grafts, including PPs. An in situ end-labeling (ISEL) technique was used to detect apoptotic cells. Indirect immunoperoxidase staining was also performed using monoclonal antibodies against rat Fas/Fas-L. RESULTS: Graft survival was prolonged in the FTY720-treated group. The number of ISEL-positive enterocytes in the allografts increased significantly on days 3, 5, and 7 compared with the isograft group. In the FTY720-treated group, the number of ISEL-positive enterocytes in the allografts was down-regulated significantly on days 3, 5, and 7 compared with untreated allograft group. In the PPs, the number of ISEL-positive mononuclear cells increased significantly in the allografts compared with the isograft group. In the FTY720-treated groups, the number of ISEL-positive mononuclear cells were down-regulated significantly in the allografts compared with the untreated allograft group. The number of Fas/FasL-positive enterocytes were increased significantly in allografts compared with isograft group. In FTY720-treated groups, the number of Fas/FasL-positive enterocytes were down-regulated significantly on day 7 compared with the untreated allograft group. In the PPs, Fas/FasL-positive mononuclear cells also increased significantly on day 7 in the allografts compared with isografts. In the FTY720-treated groups, Fas/FasL-positive mononuclear cells were down-regulated significantly in the allografts compared with the untreated allograft group. CONCLUSIONS: The number of apoptotic enterocytes, lymphocytes, and Fas/FasL-positive lymphocytes increased during small bowel graft rejection. FTY720 prevented up-regulation of the number of apoptotic enterocytes, lymphocytes, and Fas/FasL-positive lymphocytes while also prolonging small bowel allograft survival.  相似文献   
9.
Purpose Total pelvic exenteration (TPE) is the standard procedure for locally advanced rectal cancer involving the prostate and seminal vesicles. We evaluated the feasibility of bladder-sparing surgery as an alternative to TPE. Methods Eleven patients with advanced primary or recurrent rectal cancer involving the prostate or seminal vesicles, or both, underwent bladder-sparing extended colorectal resection with radical prostatectomy. The procedures performed were abdominoperineal resection (APR) with prostatectomy (n = 6), colorectal resection using intersphincteric resection combined with prostatectomy (n = 4), and abdominoperineal tumor resection with prostatectomy (n = 1). Local control and urinary and anal function were evaluated postoperatively. Results Cysto-urethral anastomosis (CUA) was performed in seven patients and catheter-cystostomy was performed in four patients. Coloanal or colo-anal canal anastomosis was also performed in four patients. There was no mortality, and the morbidity rate was 38%. All patients underwent complete resection with negative surgical margins. After a median follow-up period of 26 months there was no sign of local recurrence, and ten patients were alive without disease, although distant metastases were found in three patients. Five patients had satisfactory voiding function after CUA, and three had satisfactory evacuation after intersphincteric resection (ISR). Conclusion These bladder-sparing procedures allow conservative surgery to be performed in selected patients with advanced rectal cancer involving the prostate or seminal vesicles, without compromising local control.  相似文献   
10.
Bone marrow stem cells develop into haematopoietic and mesenchymal lineages, but have not been known to participate in steroidogenic cell production. Steroidogenic factor 1 (SF-1), also designated adrenal 4 binding protein (Ad4BP), is an essential orphan nuclear receptor for steroidogenesis as well as for adrenal and gonadal gland development. In the present study, we revealed that the adenovirus-mediated forced expression of SF-1 can transform cultured primary long-term cultured bone marrow cells into steroidogenic cells, showing the de novo synthesis of multiple steroid hormones in response to adrenocorticotropic hormone (ACTH). This finding may provide an initial step in innovative autograft cell transfer therapy for steroid hormone deficiencies.  相似文献   
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