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排序方式: 共有715条查询结果,搜索用时 31 毫秒
11.
MY Mancao LJ Sindel PH Richardson FM Silver 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(1):118-120
Croup is an acute infectious illness usually occurring in children; it is characterized by brassy cough and stridor. The main pathogens include mainly parainfluenza and influenza viruses. Recently there have been reports of prolonged croup caused by the herpes simplex viruses. We report two cases of prolonged croup due to herpes simplex types 1 and 2. We also review and summarize the reported pediatric cases of herpetic croup. 相似文献
12.
Urothelial carcinoma of the upper urinary tract: inverted growth pattern is predictive of microsatellite instability 总被引:2,自引:0,他引:2
Hartmann A Dietmaier W Hofstädter F Burgart LJ Cheville JC Blaszyk H 《Human pathology》2003,34(3):222-227
Urothelial carcinoma of the renal pelvis and ureter may develop as a manifestation of hereditary nonpolyposis colorectal cancer syndrome (HNPCC), a disorder characterized by mutation or inactivation of a number of DNA mismatch repair genes and detectable as microsatellite instability (MSI). Some urothelial carcinomas display areas of endophytic, or inverted, growth. In this study, urothelial cancers of the upper urinary tract (n = 132) from patients treated at 2 tertiary care centers were studied to identify an association between growth pattern and MSI. Thirty-five neoplasms were microsatellite unstable (26.5%), and MSI was more frequent in papillary lesions than in sessile urothelial cancers (P = .033). The amount of inverted growth was estimated as a percentage of the total tumor. The interobserver and intraobserver concordance in recognizing inverted growth was good, and 65.7% of microsatellite-unstable tumors exhibited at least 20% of an inverted growth component, compared with only 17.5% of microsatellite-stable tumors (P < .0001). In this series, inverted growth predicted MSI with a sensitivity and specificity of .82. Inverted growth in urothelial carcinomas of the upper urinary tract may serve as a marker lesion for MSI and may help identify patients who should be offered testing for HNPCC. 相似文献
13.
The ramification of the portal vein at the porta hepatis was studied by anatomic dissection performed in 32 formalin fixed human livers. In all the specimens there were branches which ran towards the caudate lobe, arising from the portal vein and either from the left or the right portal branches. Tri-and quadrifurcation of the portal vein was observed. In 5 cases (16%) there were branches arising from left portal branch or portal vein and directed anteriorly to the quadrate lobe or to the region of the gall-bladder sulcus. These branches ranged from 1.0 to 6.0 mm in diameter. The portal caudate branches were divided into 3 groups.Group 1: Branches to the papillary process; 1 or 2 branches in 26 cases (82%), 3 or 5 branches in 3 cases (9%) and no branches in 3 cases (9%); 相似文献
14.
L. J. Burgart J. Zheng Q. Shu J. G. Strickler D. Shibata 《The American journal of pathology》1995,147(4):1105-1111
Likely hot spots for mutations are mitochondrial sequences as there is less repair and more damage by carcinogens compared with nuclear sequences. A somatic 50-bp mitochondrial D-loop deletion was detected in four gastric adenocarcinomas. The deletion included the CSB2 region and was flanked by 9-bp direct repeats. The deletion was more frequent in adenocarcinomas arising from the gastroesophageal junction (4/32, 12.5%) compared with more distal tumors (0/45). Topographical analysis revealed the absence of the deletion from normal tissues except in focal portions of smooth muscle in one case. In two cases, apparent mutant homoplasmy was present throughout two tumors, including their metastases. In the two other cases, the mutation was present in only minor focal portions ( < 5%) of their primary tumors. These findings document the presence of somatic mitochondrial alterations in gastric cancer, which may reflect the environmental and genetic influences operative during tumor progression. 相似文献
15.
16.
Is fecundability associated with month of birth? An analysis of 19th and early 20th century family reconstitution data from The Netherlands 总被引:1,自引:4,他引:1
Smits LJ; Van Poppel FW; Verduin JA; Jongbloet PH; Straatman H; Zielhuis GA 《Human reproduction (Oxford, England)》1997,12(11):2572-2578
The relationship between fecundability and month of birth was investigated
in a cohort of 1526 women who married between 1802 and 1929, using only
women whose first marriage occurred before the age of 35 years. On the
basis of their time to pregnancy (TTP, calculated as time between wedding
and first birth minus gestational length), women were categorized into two
groups: fecunds (TTP up to 12 months or prenuptial conceptions, n = 1348)
and subfecunds (TTP >18 months, n = 118). By use of logistic regression,
cosinor functions with a period of 1 year or 6 months and variable shift
and amplitude were fitted through the monthly odds of subfecunds versus
fecunds. The best fitting curve was unimodal, with a zenith in September (P
= 0.13 for H0: no differences). Exclusion of childless women (n = 36,
minimum follow-up 5 years) from the subfecunds led to a similar curve (P
< 0.01), while childless women, as compared with fecunds, showed a birth
distribution that was best represented with a bimodal curve with zeniths in
January and July (P = 0.06). This study provides evidence for the existence
of differences in fecundability by month of birth. The cause of this
relationship is unclear, but may lie in a melatonin-dependent circannual
variability of the quality of the oocyte.
相似文献
17.
A model of corrective gene transfer in X-linked ichthyosis 总被引:5,自引:0,他引:5
Freiberg RA; Choate KA; Deng H; Alperin ES; Shapiro LJ; Khavari PA 《Human molecular genetics》1997,6(6):927-933
Single gene recessive genetic skin disorders offer attractive prototypes
for the development of therapeutic cutaneous gene delivery. We have
utilized X-linked ichthyosis (XLI), characterized by loss of function of
the steroid sulfatase arylsulfatase C (STS), to develop a model of
corrective gene delivery to human skin in vivo. A new retroviral expression
vector was produced and utilized to effect STS gene transfer to primary
keratinocytes from XLI patients. Transduction was associated with
restoration of full-length STS protein expression as well as steroid
sulfatase enzymatic activity in proportion to the number of proviral
integrations in XLI cells. Transduced and uncorrected XLI keratinocytes,
along with normal controls, were then grafted onto immunodeficient mice to
regenerate full thickness human epidermis. Unmodified XLI keratinocytes
regenerated a hyperkeratotic epidermis lacking STS expression with
defective skin barrier function, effectively recapitulating the human
disease in vivo. Transduced XLI keratinocytes from the same patients,
however, regenerated epidermis histologically indistinguishable from that
formed by keratinocytes from patients with normal skin. Transduced XLI
epidermis demonstrated STS expression in vivo by immunostaining as well as
a normalization of histologic appearance at 5 weeks post-grafting. In
addition, transduced XLI epidermis demonstrated a return of barrier
function parameters to normal. These findings demonstrate corrective gene
delivery in human XLI patient skin tissue at both molecular and functional
levels and provide a model of human cutaneous gene therapy.
相似文献
18.
Multiplex polymerase chain reaction. 总被引:1,自引:0,他引:1
L J Burgart R A Robinson M J Heller W W Wilke O K Iakoubova J C Cheville 《Modern pathology》1992,5(3):320-323
The polymerase chain reaction (PCR) is a widely utilized assay for specifically amplifying small fragments of DNA. Multiplex PCR is the amplification of more than one DNA fragment per reaction and has many potential uses. When more than one primer set per reaction tube is utilized, the total number of tubes in any one experiment may be reduced, conserving expensive reagents and decreasing possible contamination. Multiplex PCR allows for an assay of the gene of interest and assures that the amplification process proceeds as expected with the use of a companion control genome primer set. Multiplex PCR is useful in assaying DNA extracted from samples of immunocompromised patients in which more than one infectious agent may be suspected such as simultaneous EBV and CMV detection. Multiplex PCR offers many advantages over single reaction PCR and has been found to be an useful adjunct in our laboratory. 相似文献
19.
Marsman H Matsushita T Dierkhising R Kremers W Rosen C Burgart L Nyberg SL 《Human pathology》2004,35(4):430-435
Steatosis in donor liver biopsy specimens has been shown to correlate with graft dysfunction after orthotopic liver transplantation. This 2-part (laboratory pilot, clinical retrospective) study compared the traditional interpretation of steatosis by a pathologist with an automated measurement determined by an image analysis system. In our pilot study, Sprague-Dawley rats were studied prospectively by feeding them a choline-deficient diet for up to 7 days. In our clinical group, data from 49 consecutive recipients of cadaveric liver transplantation were reviewed retrospectively. In both studies, the percentages of microvesicular fat, macrovesicular fat, and total fat content within liver biopsy specimens were determined by an automated image analysis software program and a pathologist using the same set of slides. The association between fat content of the donor liver and patient survival and graft survival, along with levels of aspartate aminotransferase, alanine aminotransferase, prothrombin time, and total bilirubin after transplantation, were also examined in the clinical study. A direct correlation was observed between levels of macrovesicular fat determined by a pathologist and the automated software using livers from rats fed a choline-deficient diet and livers from deceased donors. A significant association was observed between macrovesicular fat content in the donor liver biopsy and graft survival by both techniques. We conclude that an image analysis system can be used to automate the determination of fat content in liver biopsy specimens, and that its findings correlate with both the visual interpretation by a pathologist and graft survival. Further study is needed to determine the role of an automated technique in the evaluation of donor livers for transplantation. 相似文献
20.
Frederick H Koh Jason MW Chua Joselyn LJ Tan Fung-Joon Foo Winson J Tan Sharmini S Sivarajah Leonard Ming Li Ho Bin-Tean Teh Min-Hoe Chew 《World journal of gastrointestinal surgery》2021,13(8):734-755
A growing body of evidence has demonstrated the prognostic significance of sarcopenia in surgical patients as an independent predictor of postoperative complications and outcomes. These included an increased risk of total complications, major complications, re-admissions, infections, severe infections, 30 d mortality, longer hospital stay and increased hospitalization expenditures. A program to enhance recovery after surgery was meant to address these complications; however, compliance to the program since its introduction has been less than ideal. Over the last decade, the concept of prehabilitation, or “pre-surgery rehabilitation”, has been discussed. The presurgical period represents a window of opportunity to boost and optimize the health of an individual, providing a compensatory “buffer” for the imminent reduction in physiological reserve post-surgery. Initial results have been promising. We review the literature to critically review the utility of prehabilitation, not just in the clinical realm, but also in the scientific realm, with a resource management point-of-view. 相似文献