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排序方式: 共有395条查询结果,搜索用时 171 毫秒
101.
Background
To allow direct comparison of bloodstream infection (BSI) rates between hospitals for performance measurement, observed rates need to be risk adjusted according to the types of patients cared for by the hospital. However, attribute data on all individual patients are often unavailable and hospital-level risk adjustment needs to be done using indirect indicator variables of patient case mix, such as hospital level. We aimed to identify medical services associated with high or low BSI rates, and to evaluate the services provided by the hospital as indicators that can be used for more objective hospital-level risk adjustment. 相似文献102.
Thirteen children with intrinsic spinal cord tumours were seen between 1984 and 1995. In only one was this the presumptive diagnosis at referral, despite a high incidence of characteristic features. Eight had presented to their local paediatrician, four to local orthopaedic teams, and one to a general surgeon. Eleven had back pain. Eleven had either spinal curvature or change in gait. The interval between onset of symptoms and diagnosis ranged from one week to six years, with a mean of 17.5 months. In nine children symptoms had been present for four or more months. In nine, unrewarding investigations had been carried out. This paper highlights typical presenting features of these tumours and how earlier diagnosis can be achieved. 相似文献
103.
Specimens of excised tissue from the porta hepatis in 26 infants with extrahepatic biliary atresia undergoing hepatic portoenterostomy were analysed histologically for the presence and size of biliary ductules. No correlation could be found between the establishment of effective biliary drainage and the number or size of biliary ductules. it is suggested that prognosis after surgery may be related to the intrahepatic lesion and age of the child at operation rather than to the histology of the extrahepatic bile duct remnants. 相似文献
104.
Rath TJ Sundgren PC Brahma B Lieberman AP Chandler WF Gebarski SS 《Neuroradiology》2005,47(3):183-188
Subependymomas are benign intraventricular tumors with an indolent growth pattern, which are usually asymptomatic, and most commonly occur in the fourth and lateral ventricles. When symptomatic, subependymomas often obstruct critical portions of the cerebrospinal fluid (CSF) pathway, causing hydrocephalus, and range from 3 cm to 5 cm in size. We report a case of an unusually massive subependymoma of the lateral ventricles treated with subtotal resection, ventriculoperitoneal shunt, and post-surgical radiation. The clinical course, radiographic and pathologic characteristics of this massive intraventricular subependymoma are discussed, as well as the differential diagnosis of lateral ventricular masses and a review of the literature concerning subependymomas. 相似文献
105.
COX-2 expression is induced by UVB exposure in human skin: implications for the development of skin cancer 总被引:12,自引:6,他引:12
Buckman SY; Gresham A; Hale P; Hruza G; Anast J; Masferrer J; Pentland AP 《Carcinogenesis》1998,19(5):723-729
Extensive documentation has validated the role of UV irradiation as a tumor
initiator and promoter, inducing both squamous and basal cell carcinomas.
Human epidermis is a tissue which undergoes active metabolism of
arachidonic acid to prostaglandins which is regulated by the action of
prostaglandin H synthase (also known as cyclooxygenase). One mechanism for
the promotional activity of UV light may involve its ability to induce
prostaglandin formation. Work in our laboratory has demonstrated that acute
exposure of human keratinocytes to UVB irradiation results in increased
production of prostaglandin E2 (PGE2). When cultured human keratinocytes
were examined after irradiation with 30 mJ/cm2 UVB in vitro, Western blot
analysis showed a 6-fold increase in COX-2 protein which was evident at 6 h
and peaked 24 h after irradiation. Furthermore, when human subjects were
irradiated on sun- protected skin with up to four times their minimal
erythema dosage (MED) and biopsied 24 h later, upregulation of COX-2
protein expression was observed via immunofluorescence microscopy. RNAase
protection assays supported this observation, showing induction of COX-2
message which peaked at approximately 12 h following irradiation in vitro.
Furthermore, human squamous cell carcinoma biopsies exhibited strongly
enhanced staining for COX-2 protein via immunohistochemistry and Western
analysis when compared to normal non-sun-exposed control skin. Together,
these data demonstrate acute upregulation of COX-2 via UVB irradiation and
suggest the need for further studies of COX-2 expression as a potential
pharmacological target mediating human skin tumor development.
相似文献
106.
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108.
S Hopkins‐Donaldson R Cathomas AP Simes‐Wüst S Kurtz L Belyanskya RA Stahel U Zangemeister‐Wittke 《International journal of cancer. Journal international du cancer》2003,107(6):1058-1058
The original article to which this Erratum refers was published in International Journal of Cancer (2003) 106(2) 160–166 相似文献
109.
异型缝隙连接通道和磷酸化对心脏缝隙连接的调变 总被引:5,自引:0,他引:5
目的 检测由缝隙连接蛋白(connexin,Cx)43和Cx45组成的多种异型缝隙连接通道(her—eromultimeric gap junction channels,HGJC)和磷酸化对缝隙连接(gap junction,GJ)的调变作用。方法 将转染了编码为Cx43或Cx45的DNA后的Hela细胞放置在一起共同培养组成双侧和单侧异型GJ通道。显微注射若丹明123(rhodamine123,Rh)检测经200nmol/L十四(烷)酰佛波醇乙酸酯(12-0-tetrade—canoylphorbol-13-acetae,TPA)处理前后,在紫外光显示下由Cx43和Cx45所组成的不同GJ通道对荧光染料的偶联率(coupling ratio)。结果 在不同的GJ中,同型GJ通道Cx43(homotypie Cx43,HoCx43)偶联率最高。从Cx45侧注入荧光染料的单侧异型GJ通道45(mono-heteromeric Cx45-Cx43/45,MH45)偶联率较之从Cx43/45侧注入荧光染料的MH45、双侧异型GJ通道Cx43/45(bi-heteromeric Cx43/45,BH43/45)及同型GJ通道Cx45(homotypic Cx45,HoCx45)等的偶联率是最低的。根据HoCx43或HoCx45通道的偶联率对各型通道偶联率进行标准化处理。BH43/45和MH43通道的偶联率均较HoCx43降低。对MH45通道来说,从Cx43/45侧注射的通道偶联率大于从Cx45侧注射的偶联率。TPA处理后HoCx43的偶联率降低,而当Cx43和Cx45组合成BH43/45和MH43通道后其偶联率下降更显著。结论 Cx43和Cx45共同表达可构成BH43/45、MH43和MH45等异型通道,而这些通道可降低细胞间的通讯并对磷酸化的作用不敏感。单侧异型GJ通道的偶联率取决于染料注射的方向。 相似文献
110.