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   232篇
  免费   2篇
  国内免费   19篇
儿科学   5篇
妇产科学   5篇
基础医学   14篇
口腔科学   5篇
临床医学   20篇
内科学   37篇
神经病学   1篇
特种医学   96篇
外科学   25篇
综合类   7篇
预防医学   7篇
药学   22篇
肿瘤学   9篇
  2022年   1篇
  2021年   1篇
  2020年   1篇
  2019年   1篇
  2018年   2篇
  2017年   1篇
  2016年   1篇
  2015年   3篇
  2014年   8篇
  2013年   3篇
  2012年   6篇
  2011年   1篇
  2010年   4篇
  2009年   3篇
  2008年   5篇
  2007年   16篇
  2006年   6篇
  2005年   11篇
  2004年   4篇
  2003年   2篇
  2002年   2篇
  2001年   2篇
  2000年   3篇
  1999年   1篇
  1998年   10篇
  1997年   21篇
  1996年   11篇
  1995年   9篇
  1994年   13篇
  1993年   9篇
  1992年   1篇
  1991年   1篇
  1990年   2篇
  1989年   18篇
  1988年   7篇
  1987年   8篇
  1986年   12篇
  1985年   8篇
  1984年   3篇
  1983年   3篇
  1982年   8篇
  1981年   3篇
  1980年   8篇
  1978年   2篇
  1977年   2篇
  1976年   3篇
  1975年   2篇
  1968年   1篇
排序方式: 共有253条查询结果,搜索用时 15 毫秒
1.
2.
3.
PEG-rHuMGDF injected daily in normal mice causes a rapid dose-dependent increase in megakaryocytes and platelets. At the same time that platelet numbers are increased, the mean platelet volume (MPV) and platelet distribution width (PDW) can be either decreased, normal, or increased depending on the dose and time after administration. Thus, PEG-rHuMGDF at a low dose causes decreases in MPV and PDW, MGDF at an intermediate dose causes an initial increase followed by a decrease in MPV and PDW, and PEG-rHuMGDF at higher doses causes an increase in MPV and PDW followed by a gradual normalization of these platelet indices. In addition to the expected thrombocytosis after 7 to 10 days of daily injection of high doses of PEG-rHuMGDF, a transient decrease in peripheral red blood cell numbers and hemoglobin is noted accompanied in the bone marrow by megakaryocytic hyperplasia, myeloid hyperplasia, erythroid and lymphoid hypoplasia, and deposition of a fine network of reticulin fibers. Splenomegaly, an increase in splenic megakaryocytes, and extramedullary hematopoiesis accompany the hematologic changes in the peripheral blood and marrow to complete a spectrum of pathologic features similar to those reported in patients with myelofibrosis and megakaryocyte hyperplasia. However, all the PEG-rHuMGDF-initiated hematopathology including the increase in marrow reticulin is completely and rapidly reversible upon the cessation of administration of PEG-rHuMGDF. Thus, transient hyperplastic proliferation of megakaryocytes does not cause irreversible tissue injury. Furthermore, PEG-rHuMGDF completely ameliorates carboplatin-induced thrombocytopenia at a low-dose that does not cause the hematopathology associated with myelofibrosis.  相似文献   
4.
Tumor cells upregulate myriad proteins that are important for pH regulation, resulting in the acidification of the extracellular tumor microenvironment (TME). Abnormal pH is known to dampen immune function, resulting in a worsened anti-tumor immune response. Understanding how extrinsic alterations in pH modulate the interactions between immune cells and tumors cells will help elucidate opportunities for new therapeutic approaches. We observed that pH impacts the function of immune cells, both natural killer (NK) and T cells, which is relevant in the context of a highly acidic TME. Decreased NK and T cell activity was correlated with decreasing pH in a co-culture immune cell-mediated tumor cell-killing assay. The addition of pH-modulating drugs cariporide, lansoprazole, and acetazolamide to the co-culture assay was able to partially mitigate this dampened immune cell function. Treatment of colorectal cancer (CRC) cells with NHE1 inhibitor cariporide increased CRC cell-secreted cytokines involved in immune cell recruitment and activation and decreased cytokines involved in epithelial-mesenchymal transition (EMT). Cariporide treatment also decreased CRC cell shed TRAIL-R2, TRAIL-R3, and PD-L1 which is relevant in the context of immunotherapy. These experiments can help inform future investigations into how the pH of the tumor microenvironment may be extrinsically modulated to improve anti-tumor immune response in solid tumors such as colorectal cancer.  相似文献   
5.
Both ultrasonography (US) and cholescintigraphy are used to study gallbladder dynamics. The present study was undertaken to determine whether the two methods provide the same or different information relating to gallbladder emptying. Emptying was simultaneously studied with both methods during infusion of graded physiologic doses of cholecystokinin (CCK) in six healthy subjects. Infusion of stepwise increasing doses of CCK, ranging from 0.03 to 0.5 Ivy dog units per kilogram of body weight per hour (IDU/kg.h), induced significant dose-related increases in plasma CCK, decreases in gallbladder volume assessed with US, and gallbladder emptying assessed with cholescintigraphy. The threshold dose for inducing significant gallbladder emptying was 0.13 IDU/kg.h, as determined with both techniques, indicating similar detection limits. There was a highly significant correlation between decreases in gallbladder volume and decreases in radioactive counts over the gallbladder region, with a tendency toward greater gallbladder responses at sonography during the early phase of gallbladder contraction and toward greater responses at cholescintigraphy during the later phase of gallbladder contraction. It is concluded that these methods can be used interchangeably for the quantitation of gallbladder emptying.  相似文献   
6.
OBJECTIVE: To present early experience in managing complex renal calculi using a combined ureteroscopic and percutaneous approach, as complex and branched renal calculi often require multiple access tracts during percutaneous nephrolithotomy (PNL), and the combined use of flexible ureteroscopy and PNL has the potential to reduce the inherent morbidity of several tracts. PATIENTS AND METHODS: The study included seven patients (mean age 54 years) with multiple, branched, large-volume renal calculi suitable for management with PNL. Preoperative data, including patient demographics, stone location and stone surface area, were recorded. After informed consent, the patients underwent combined PNL and ureteroscopy in one session. Intraoperative data, including the location of PNL puncture sites, operative duration and complications, were analysed. Stone-free rates were determined by follow-up imaging at 3 months. RESULTS: All patients had either two or more stones in separate locations in the collecting system, or staghorn stones involving multiple calyces. The mean stone burden was 666 mm(2). All patients had only one percutaneous access tract. The mean operative duration was 142 min and the mean blood loss 79 mL. Two patients had small residual stones (< 3 mm), that required ureteroscopic intervention as they failed to pass spontaneously by 3 months after the initial combined procedure. The convalescence was similar to that in our current PNL practice; imaging showed that five of the patients were stone-free. CONCLUSIONS: Combined PNL and ureteroscopic management can effectively reduce the number of percutaneous access tracts which would otherwise be required for managing complex and branched renal calculi, as stones in an unfavourable location relative to the access tract can be relocated and fragmented within easy reach of the single nephrostomy tract. This manoeuvre reduces potential patient morbidity and blood loss but with no significant effect on stone-free rates and operative durations.  相似文献   
7.
8.
Major motor atrophic patterns in the face and neck: CT evaluation   总被引:1,自引:0,他引:1  
Harnsberger  HR; Dillon  WP 《Radiology》1985,155(3):665-670
Cranial nerve deficits from various pathologic processes of the head and neck may result in characteristic patterns of denervation muscular atrophy. Such atrophic patterns may be clues to the location and extent of the lesion, particularly when cranial nerves are involved early in the course of the disease process. Thirty-six patients with computed tomographic (CT) evidence of muscular atrophy secondary to pathologic conditions involving the motor division of cranial nerves were examined. Five characteristic denervation muscular atrophy patterns seen on CT scans were identified. In several patients, identification of the muscular atrophy pattern was the only clue to the presence of a pathologic condition. Recognition of these atrophic patterns can prevent misinterpretation of their CT appearance and direct the CT examination to the course of the compromised cranial nerve from the brainstem to its peripheral innervation.  相似文献   
9.
PURPOSE OF REVIEW: Stone disease continues to plague humankind. Recent innovations in minimally invasive surgery, however, have decreased morbidity for the treatment of lithiasis, once only amenable to open surgical techniques. These advances in stone management have also been paralleled in the radiographic armamentarium. Herein, we describe the evolution of initial radiographic workup for urolithiasis, from abdominal radiograph to three-dimensional computed tomography and some of the novel applications thereof. RECENT FINDINGS: Previously, abdominal radiography was the only modality available for the visualization of calculi. Subsequently, the development of intravenous contrast aided in evaluating renal function, detecting the presence and location of obstruction, and in identifying filling defects. Most recently, prospective randomized trials have demonstrated improved sensitivity and specificity using noncontrast helical computed tomography rather than intravenous pyelogram with regard to the initial evaluation of acute flank pain. Further attempts to lower the overall radiation dose without compromising efficacy have also been introduced. Currently, the volume of calculus disease can be better quantified and somewhat qualified from three-dimensional computer software, thereby optimizing stone management. SUMMARY: Considerable progress has been made using minimally invasive techniques in the treatment of nephrolithiasis. Furthermore, advances in radiographic computer hard- and software applications allow for a rapid acquisition time and improved image quality without sacrificing diagnostic accuracy. In time, it is likely that the combination of these enhanced imaging modalities will lead to an improvement in stone localization, fragmentation and stone-free rates.  相似文献   
10.
脐部给药的多塞平栓研制及应用   总被引:2,自引:0,他引:2  
目的:研制透皮制剂多塞平栓,考察其治疗各型急、慢性荨麻疹的临床疗效。方法:多塞平以甘油明胶为质,氮酮为促透剂,制成栓剂,经脐部给药,观察50个病例,与口服多塞平片作对照,观察临床疗效。结果:多塞平栓治疗各型急、慢性荨麻疹,总有效率为94.0%,经统计学分析,P〈0.05,差异具显著性。结论:本品制备工艺可行,疗效确切,用药剂量小,无副作用,具有进一步研究、开发的价值。  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