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101.
102.
Intracranial aneurysms (IAs) are found more often in patients with aortic coarctation (AC) than in the general population and aneurysm rupture occurs much earlier in the lives of these patients when there is coexistent AC. The diagnosis of AC is frequently made only after a serious cerebrovascular complication has developed. The aim of this paper is to call attention to AC in patients presenting with aneurysmal subarachnoid hemorrhage. The literature is reviewed, the key clinical features are highlighted, and the proposed pathogenesis of this association is discussed. The authors present clinical information and imaging data obtained in three young patients with ruptured IAs that were associated with initially unnoticed AC. Abnormal results of cardiovascular examinations led the authors to consider an underlying AC, which was later confirmed by aortography. These aneurysms were successfully treated prior to correction of the ACs. The diagnosis of AC should be considered in adolescent and young adult patients presenting with IAs.  相似文献   
103.
104.
Weaver  DA; Hei  TK; Hukku  B; McRaven  JA; Willey  JC 《Carcinogenesis》1997,18(6):1251-1257
To establish a cell culture model for lung carcinogenesis, independent populations of the human papillomavirus 18-immortalized human bronchial epithelial cell line BEP2D were treated with high linear energy transfer radon-simulated alpha-particles, expanded and xenotransplanted into Nu/Nu mice. Six independent cell lines were established from tumors that developed from three separate radiation treatments as follows: treatment (Tx) 1 (30 cGy--two doses), H2BT, Tx 2 (30 cGy-- single dose), R30T1L, R30T2 and R30T3L, Tx 3 (30 cGy--single dose), H1ATN and H1ATBA1. Cytogenetic analysis revealed common changes in all tumor lines: loss of the Y chromosome (ch), one of three copies of ch8, one of three copies of ch14, and one of two copies of ch4p16-pter and ch11p15-pter. Analysis of polymerase chain reaction-amplified short tandem repeats of informative loci confirmed the loss of chY in all lines and loss of heterozygosity (LOH) at eight loci spanning the length of ch8 in all lines from Tx's 1 and 2. Our data support previous studies indicating the presence of tumor suppressor genes on ch8. LOH also was confirmed on ch14 at locus D14S306 in all cell lines from Tx 2 and in one of two lines from Tx 3. This region, 14q12-q13, may contain changes in one of the five known somatostatin receptor genes (SSTR1). No LOH was detected at any of the informative loci tested for on ch4 or ch11.   相似文献   
105.
106.
Childhood tuberculosis is perceived by many as a disease of the past. Experience in a children's hospital serving a deprived population suggested that tuberculosis and other mycobacterial infections were not declining in clinical practice. Fifty three tuberculous and 11 atypical mycobacterial infections were identified between 1978 and 1992. There was no decline in tuberculosis and nine of the 11 atypical infections occurred in the last five years. Altogether 40% of cases of tuberculosis were in non-Asian children; 32% had arrived in the UK or visited family overseas in the previous year; and 38% had a history of tuberculosis contact, usually a close adult relative. Nationally, the previous decline in tuberculosis in all ages has reversed. In the local health districts in London's east end, childhood tuberculosis has also stopped declining and seems to be increasing. It is regrettable that BCG vaccination has been abolished by some districts in the UK, against current recommendations. Childhood tuberculosis is still common in the practice described here, including among children who do not fall into conventionally recognised high risk groups. Inner city dwellers and junior doctors are both highly mobile populations, adding to the risk that paediatricians, particularly those in training, may encounter tuberculosis with little or no previous experience of the condition.  相似文献   
107.
Background: Small bowel cancer is a relatively rare tumor with an incidence of 2,700 new cases and 900 deaths per year. The influence of stage on survival has been reported only once previously. Patterns of recurrence are unreported. Methods: All cases of small bowel cancer treated at our hospital over a 30-year period (1960–1989) were reviewed. Results: The site of most cancers was the duodenum (46%), followed in frequency by the jejunum (33%) and the ileum (21%). Adenocarcinoma was the most common histology (63%), followed in frequency by lymphoma (15%), leiomyosarcoma (13%), carcinoid tumors (6%), and miscellaneous (3%). Analysis of stage distribution by site showed a decrease in stages I and II with more distal locations. Associated cancers occurred in 11%, but none were seen in the group with carcinoid tumors. Actuarial 10-year survival rates were 24% for those with adenocarcinoma (all stages) 75% for stage I, 25% for those with stage II, and 0% for stage III. A subgroup of 10 patients who underwent a pancreaticoduodenectomy (one stage I, seven stage II, two stage III) had a 30% 10-year survival rate. Those patients with lymphoma had a 12% 10-year survival rate, and those with leiomyosarcoma had a 20% 10-year survival rate. A 100% 10-year survival rate was observed in those with carcinoid tumors. Peritoneal carcinomatosis was the most common failure pattern (33%), followed in frequency by local recurrence in 23% and abdominal wall recurrence in 15%. Conclusions: A correlation exists between the pathologic stage and the survival rate for adenocarcinoma. The most common recurrence pattern for adenocarcinoma was carcinomatosis, followed in frequency by abdominal wall recurrence. Leiomyosarcoma preferentially metastasizes to the liver. The results of this study were presented at the 46th Annual Cancer Symposium of The Society of Surgical Oncology, Los Angeles, California, March 18–21, 1993.  相似文献   
108.
109.
Multisection, dual-echo magnetic resonance (MR) transaxial images of blood vessels contain both anatomic and qualitative information about flow. Even so, the images are produced as a series of two-dimensional tomographic sections from which full visualization of connected structures is difficult. A computer algorithm was developed that automatically detects flowing blood based on pixel intensity and calculated T2 and provides reconstructed views of vessels while analyzing and displaying flow characteristics. Images of abdominal vessels, aortic aneurysms, and the heart were encoded by flow and color to demonstrate depth. In addition, these data were reconstructed to derive a more accurate assessment of patency. With this technique, transaxial images can be used to analyze flow patterns, determine patent areas, and visualize all levels of vessels in a single image.  相似文献   
110.
Seventy cases of congential heart disease including the most frequent types were studied, and wedge hepatic venous pressure (WHVP) was measured in each. The mean pressure was determined in the "jammed position" and in the free hepatic veins, inferior vena cava, and low right atrium. The average mean WHVP was 7.0 mm Hg, 5.0 in inferior vena cava, and 3.4 in the right atrium. A direct relationship was found between wedge hepatic venous pressure of the inferior vena cava and the low right atrium, but not other parameters. Ten patients had a mean pressure above 10 mm Hg. We believe that in many circumstances in patients with congenital heart disease, liver function may be abnormal and high values of wedge hepatic venous pressure may also be found.  相似文献   
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