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排序方式: 共有1985条查询结果,搜索用时 15 毫秒
91.
Cytogenetic and molecular genetic analysis of tumorigenic human bronchial epithelial cells induced by radon alpha particles 总被引:4,自引:1,他引:4
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
92.
93.
HM Goodyear JC Moore-Gillon EH Price VF Larcher MO Savage CB Wood 《Archives of disease in childhood》1993,69(2):229-231
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
94.
Dr. Daniel B. Frost MD Philip D. Mercado MD Jon S. Tyrell MD 《Annals of surgical oncology》1994,1(4):290-295
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
95.
96.
Hale JD; Valk PE; Watts JC; Kaufman L; Crooks LE; Higgins CB; Deconinck F 《Radiology》1985,157(3):727-733
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
97.
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
98.
99.
Sotillo M Carretié L Hinojosa JA Tapia M Mercado F López-Martín S Albert J 《Neuroscience letters》2005,373(1):5-9
Though neuropsychological data indicate that the right hemisphere (RH) plays a major role in metaphor processing, other studies suggest that, at least during some phases of this processing, a RH advantage may not exist. The present study explores, through a temporally agile neural signal--the event-related potentials (ERPs)--, and through source-localization algorithms applied to ERP recordings, whether the crucial phase of metaphor comprehension presents or not a RH advantage. Participants (n=24) were submitted to a S1-S2 experimental paradigm. S1 consisted of visually presented metaphoric sentences (e.g., "Green lung of the city"), followed by S2, which consisted of words that could (i.e., "Park") or could not (i.e., "Semaphore") be defined by S1. ERPs elicited by S2 were analyzed using temporal principal component analysis (tPCA) and source-localization algorithms. These analyses revealed that metaphorically related S2 words showed significantly higher N400 amplitudes than non-related S2 words. Source-localization algorithms showed differential activity between the two S2 conditions in the right middle/superior temporal areas. These results support the existence of an important RH contribution to (at least) one phase of metaphor processing and, furthermore, implicate the temporal cortex with respect to that contribution. 相似文献
100.
Mercado U Arroyo de Anda R Avendaño L Araiza-Casillas R Avendaño-Reyes M 《Clinical and experimental rheumatology》2005,23(5):685-688
OBJECTIVE: To assess the metoclopramide response in patients with early diffuse systemic sclerosis (dSSc) and the acute effects of intravenous (IV) metoclopramide on the lower esophageal sphincter (LES). METHODS: Twenty-one patients with early dSSc (mean age 41.4 +/- 9.8 yrs., mean disease duration 2.47 +/- 0.75 yrs.) were prospectively evaluated. Six patients with late dSSc (mean age 52.6 +/- 9.1 yrs., mean disease duration 9.5 +/- 2.5 yrs.) were used as control group. All underwent solid-state esophageal manometry at rest and 15 minutes later received 10 mg of metoclopramide in an intravenous single bolus. RESULTS: We found that the mean LES pressures measured by the station pull-through technique significantly increased in both early and late dSSc patients after metoclopramide administration (p < 0.05). While early dSSc patients did improve the mean residual pressures (p < 0.05), late dSSc patients did not (p > 0.05). In the esophageal body (EB), the mean contractions amplitude at 18, 13, 8, and 3 cm above the LES was < 20 mm Hg for both groups. However, peristaltic contraction velocitiy was significantly higher in early dSSc patients (< 0.05) than in that with late dSSc (p > 0.05). Our study did not show any major differences when comparing both groups. No side effects were seen. CONCLUSIONS: The results of our study show that metoclopramide may improve LES pressures in patients with early and late dSS. Metoclopramide improve the mean residual pressure in patients with early dSSc, but not in late dSSc patients. Although esophageal contractions amplitude were significantly improved, they did not achieve a pressure > 20 mm Hg. Because metoclopramide can be used orally, it may mitigate both dysphagia and heartburn. 相似文献