首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   239篇
  免费   9篇
耳鼻咽喉   1篇
儿科学   1篇
基础医学   35篇
口腔科学   78篇
临床医学   14篇
内科学   18篇
皮肤病学   4篇
神经病学   22篇
特种医学   4篇
外科学   35篇
综合类   1篇
预防医学   8篇
药学   7篇
肿瘤学   20篇
  2020年   3篇
  2018年   3篇
  2017年   2篇
  2016年   1篇
  2015年   2篇
  2014年   1篇
  2013年   3篇
  2012年   10篇
  2011年   8篇
  2009年   2篇
  2008年   8篇
  2007年   11篇
  2006年   7篇
  2005年   8篇
  2004年   9篇
  2003年   8篇
  2002年   14篇
  2001年   16篇
  2000年   14篇
  1999年   14篇
  1998年   1篇
  1997年   2篇
  1996年   4篇
  1995年   1篇
  1993年   1篇
  1992年   8篇
  1991年   9篇
  1990年   8篇
  1989年   9篇
  1988年   14篇
  1987年   4篇
  1986年   1篇
  1985年   5篇
  1984年   5篇
  1983年   7篇
  1982年   1篇
  1981年   1篇
  1979年   1篇
  1978年   3篇
  1976年   1篇
  1974年   3篇
  1973年   2篇
  1971年   3篇
  1970年   5篇
  1969年   2篇
  1968年   1篇
  1965年   2篇
排序方式: 共有248条查询结果,搜索用时 15 毫秒
1.
2.
We developed a novel method which enables bloodless exposure of the levator veli palatini muscle in rat in order to investigate the physiological properties of this muscle. The levator veli palatini muscle which is innervated by a branch of the glossopharyngeal nerve showed rhythmic spontaneous movement in rats. Cutting the branch supplying LVP of the glossopharyngeal nerve caused cessation of the spontaneous movement of the levator veli palatini muscle. The spontaneous discharges of the glossopharyngeal nerve were synchronized with those of the phrenic nerve. A mixture of 95% oxygen and 5% room air influenced the efferent discharges from the branch of the glossopharyngeal nerve supplying the levator veli palatini muscle. These findings indicate that the motor nerve supply to the levator veli palatini muscle is the glossopharyngeal nerve, and the levator veli palatini muscle is related to the respiratory system, in particular with inspiration in rats.  相似文献   
3.
The radial forearm flap, or the forearm flap, is called "Chinese flap" for its development of the chinese doctors, and is originally designed for the correction to the post-burn contraction of the face and neck. The radial forearm flap is one of the fasciocutaneous flap, supplied by the radial artery, and transferred as a single-stage reconstruction micro-surgically. In oral and maxillofacial region, the deltopectral flap (D-P flap) and the pectralis major myocutaneous flap (P-M-M-C flap) are mainly used for the reconstruction. These flaps, however, are sometimes too bulky and limited to transfer, and more require two-stage operations. On the other hand, as the forearm flap being thin and pliable, some doctors use this flap micro-surgically at single-stage free flap reconstruction. Before two years, we have begun to transfer the radial forearm flap for the intra-oral reconstruction. The operation method is as follows. Design and Elevation of the Radial Forearm Flap 1. Using the ultrasonic doppler flow meter, the radial artery and the subcutaneous forearm veins are marked on the skin. 2. The flap is designed 20% larger according to the pattern to be reconstructed, with the distal section of the radial artery as an axis on the forearm and the median vein of forearm inclusively. 3. Before the operation, Allen test must be performed in order to determine whether the hand will survive without a radial arterial in-put. 4. The operation is performed with a arm tourniquet. The margin of the flap are incised down to the deep fascia, isolating and preserving the proximal subcutaneous veins as required.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
4.
Primary renal angiosarcoma is very rare. To our knowledge, only 15 cases have been reported to date. A 77-year-old Japanese man with a unilateral kidney presented with massive hematuria followed by renal failure. A renal tumor was suspected and a left nephrectomy was performed. The histopathological diagnosis was angiosarcoma of the kidney. A hemorrhagic tumor measuring 10 × 5 cm and clotted blood was found in the modularly area. The atypical tumor cells had a sinusoidal and solid appearance, and showed Immunohistochemically positive reactions for some of the endothelial markers. The patient died about 21 months after the nephrectomy and the autopsy revealed massive metastases to the liver and retroperitoneum. One of the differential diagnoses of the case was anglomyolipoma, because the tumor cells were relatively bland in their histological appearance with entrapped fat cells in the pelvic area. Fifteen case reports with titles that included the term 'hemangiosarcoma/anglosarcoma', 'hemangioendothelloma/endothelloma' or 'vascular sarcoma' of the kidney were reviewed and compared to the present case.  相似文献   
5.
To evaluate the pathogenetic roles of immune complexes and alveolar hyaline membrane in idiopathic interstitial pneumonia (IIP), immunohistological and ultrastructural studies of the kidney and lung were performed in 23 cases of IIP, 19 cases of autoimmune diseases, 17 cases of interstitial pneumonia other than IIP, and 11 cases of bronchopneumonia as a control group. None of the cases of IIP or interstitial pneumonia other than IIP showed immune complexes in the alveolar and glomerular capillary walls. On the other hand, one case of SLE was positive for IgG and components of complement along the alveolar and glomerular capillary walls. The alveolar hyaline membrane in the present cases revealed immunoglobulins as well as components of complement, which were poorly soluble in chaotropic solution or acidic buffer. These results indicate that circulating immune complexes play a minor role in the pathogenesis of IIP and other types of interstitial pneumonia, and that there is no relationship between immune complex deposition in alveoli and the alveolar hyaline membrane. It is necessary to further investigate factors other than immune complexes involved in alveolar tissue damage and to clarify the significance of the hyaline membrane in the processes occurring from acute changes to pulmonary fibrosis in IIP.  相似文献   
6.
Although rhythmic jaw movement in feeding has been studied in mammals, such as rats, rabbits and monkeys, the cellular and molecular mechanisms underlying it are not well understood. Transgenic and gene-targeting technologies enable direct control of the genetic makeup of the mouse, and have led to the development of a new category of reagents that have the potential to elucidate the cellular and molecular mechanisms of neural networks. The present study attempts to characterize rhythmic jaw movements in the mouse and to demonstrate its relevance to rhythmic jaw movements found in higher mammals using newly developed jaw-tracking systems and electromyograms of the masticatory muscles. The masticatory sequence of the mouse during feeding was classified into two stages, incision and chewing. Small and rapid (8 Hz) open-close jaw movements were observed during incision, while large and slow (5 Hz) open-close jaw movements were observed during chewing. Integrated electromyograms of the masseteric and digastric muscles were larger during chewing than those observed during incision. Licking behavior was associated with regular (8 Hz), small open-close jaw movements with smaller masseteric activity than those observed during mastication. Grooming showed variable patterns of jaw movement and electromyograms depending on the grooming site. These results suggest that there are neuronal mechanisms producing different frequencies of rhythmic jaw movements in the mouse, and we conclude that the mouse is useful for understanding rhythmic jaw movements in higher mammals.  相似文献   
7.
In this study, we examined the corrosion behaviors of pure titanium, the alloys Ti-6Al-4V and Ti-6Al-7Nb, and the new experimental alloys Ti-Pt and Ti-Pd using anodic polarization and corrosion potential measurements in an environment containing fluoride. Before and after immersion in the test solutions, we made observations using a scanning electron microscope. The test solutions included an artificial saliva containing 0.2% NaF (corresponding to 905 ppm F) and an artificial saliva with a low concentration of oxygen. Although the surfaces of the Ti-Pt and Ti-Pd alloys were not affected by an acidic environment containing fluoride, the surfaces of the pure titanium, the Ti-6Al-4V alloy, and the Ti-6Al-7Nb alloy were markedly roughened by corrosion. The surfaces of the pure titanium, the Ti-6Al-4V alloy, and the Ti-6Al-7Nb alloy were microscopically damaged by corrosion when they were immersed in the solution containing a low concentration of dissolved oxygen, even with a fluoride concentration included in the commercial dentifrices. In this situation, however, the surfaces of the new Ti-Pt and Ti-Pd alloys were not affected. These alloys are expected to be of use in dental work as new titanium alloys with high corrosion resistances.  相似文献   
8.
Ana ID  Matsuya S  Ohta M  Ishikawa K 《Biomaterials》2003,24(18):3061-3067
In this study, the effects of added bioactive glass on the basic setting properties of a commercially available resin-modified glass ionomer cement were investigated with respect to setting time, mechanical strength, and setting mechanism. It was found to be clinically acceptable whether the setting time was extended or shortened depending on the type of bioactive glass added. The compressive strength of the set cement containing the bioactive glass decreased and was much higher when compared with the conventional type glass ionomer cement containing bioactive glass. The Fourier-transform infrared and 13C CP/MAS-NMR spectroscopies revealed that the extent of the acid-base reaction was larger in the cements containing bioactive glass than in the commercial resin-modified glass ionomer cement because of its high basicity in the bioactive glass. The 27Al MAS-NMR showed that crosslinking of the carboxylates in the polymeric acid by Al proceeded less in the cement containing the bioactive glass.  相似文献   
9.
We have constructed a plasmid to express and secrete dextranase in the oral bacterium Streptococcus gordonii. The dextranase gene from Arthrobacter sp. strain CB-8 was linked to a promoter and a DNA sequence encoding the signal peptide of Streptococcus downei glucosyltransferase I (gtfI) followed by the Escherichia coli rrnBt1t2 terminator and inserted in the shuttle vector pVA838. S. gordonii transformed with this plasmid (pMNK-4) expressed and secreted mature Arthrobacter dextranase. The transformant was found to repress the firm adherence of water-insoluble glucan in a coculture experiment with cariogenic bacteria, Streptococcus sobrinus, in the presence of sucrose. Such genetically engineered oral bacteria could provide a therapy to prevent dental caries.  相似文献   
10.
Outcome of surgery in cystic renal cell carcinoma   总被引:30,自引:0,他引:30  
OBJECTIVES: To review cases of cystic renal cell carcinoma treated surgically at our institution and define their clinical and histopathologic features. METHODS: Between 1986 and 1998, 21 patients with cystic renal cell carcinoma were treated surgically. Cystic renal cell carcinoma was categorized using Hartman's classification. RESULTS: Histopathologic examination demonstrated cystic necrosis in 11 patients, multilocular cystic renal cell carcinoma in 9, and unilocular cystic renal cell carcinoma in 1 patient. Tumors were incidentally found during an evaluation of unrelated disease or a general health checkup in 14 patients (67%). The mean tumor size was 5.6 cm (range 0.5 to 12) for cystic necrosis and 5.4 cm (range 2 to 9) for multilocular cystic renal cell carcinoma. All 9 cases of multilocular cystic renal cell carcinoma were of the clear cell type and tumor grade 1. The mean follow-up period was 65 months (range 9 to 141). The 5-year disease-specific survival rates for multilocular cystic renal cell carcinoma and cystic necrosis were 100% and 80%, respectively. CONCLUSIONS: The prognosis for patients with cystic renal cell carcinoma is better than that for patients with solid tumors. In particular, the prognosis of multilocular cystic renal cell carcinoma is excellent. Multilocular cystic renal cell carcinoma represents a distinct subtype of renal cell carcinoma that can be completely cured by surgery.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号