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31.
Impact of smoking on cancer stage at diagnosis. 总被引:2,自引:0,他引:2
Nathan L Kobrinsky Marilyn G Klug Peggy Jo Hokanson Diane E Sjolander Larry Burd 《Journal of clinical oncology》2003,21(5):907-913
BACKGROUND: Studies evaluating the relationship between smoking and cancer spread are limited. METHODS: We studied the relationship between cancer stage at diagnosis (local, regional, or metastatic) and smoking history (current, previous, or nonsmoker). For lung cancer, patterns of spread were also studied. RESULTS: In a tumor registry for eastern North Dakota, northwestern Minnesota, and northern South Dakota, 11,716 cases were identified from 1986 to 2001. Current smokers (relative risk [RR], 2.11; 95% confidence interval, 1.93 to 2.32; P <.001) and previous smokers (RR, 1.56; 95% confidence interval, 1.42 to 1.72; P <.001) had an increased risk of metastatic disease at diagnosis. Current smokers (RR, 1.39; 95% confidence interval, 1.29 to 1.51; P <.001), but not previous smokers, also had an increased risk of regional disease. An increase in metastatic disease was most evident for prostate cancer (RR, 1.53; P =.003). An increase in regional disease was most evident for head and neck (RR, 3.53; P <.001), prostate (RR, 1.83; P =.030), and breast cancer (RR, 1.22; P =.005). Compared with previous smokers, current smokers with metastatic lung cancer were more likely to have involvement of the brain (33.6% v 23.0%; P =.004), bone marrow, adrenal gland, and pericardium (24.7% v 15.9%; P =.004). CONCLUSION: Previous or current smoking is a risk factor for increased cancer stage in a wide range of malignancies. Further study is required to determine whether this association is causal. 相似文献
32.
Larry Demco 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2003,7(2):141-145
Complications of laparoscopy are categorized into trocar insertion complications, complications resulting from image quality, and complications resulting from instrumentation. Microlaparoscopy also has similar complications and additional complications when being performed in the awake patient. Each of these complications is reviewed as they apply to microlaparoscopy. The results reveal that the seriousness of the complication is directly dependent on the size of the perforation. Therefore, surgeons' reluctance to downsize the instruments used is increasing the laparoscopy complication rate. Using smaller-diameter trocars and instruments reduces laparoscopic complication rates. 相似文献
33.
Laparoscopic feeding jejunostomy: also a simple technique 总被引:2,自引:1,他引:1
Michael H. Albrink James Foster Alexander S. Rosemurgy Larry C. Carey 《Surgical endoscopy》1992,6(5):259-260
Summary Placement of feeding tubes is a common procedure for general surgeons. While the advent of percutaneous endoscopic gastrostomy
has changed and improved surgical practice, this technique is contraindicated in many circumstances. In some patients placement
of feeding tubes in the stomach may be contraindicated due to the risks of aspiration, gastric paresis, or gastric dysmotility.
We describe a technique of laparoscopic jejunostomy tube placement which is easy and effective. It is noteworthy that this
method may be used in patients who have had previous abdominal operations, and it has the added advantage of a direct peritoneal
view of the viscera. We suggest that qualified laparoscopic surgeons learn the technique of laparoscopic jejunostomy. 相似文献
34.
Summary An infant with persistent truncus arteriosus associated with splenic agenesis and the asplenia syndrome is reported, including clinical, echocardiographic and autopsy findings. To the authors' knowledge this association has not been previously reported. 相似文献
35.
Bruce F. Waller Charles M. Orr James Van Tassel Thomas Peters Edward Fry James Hermiller Larry D. Grider 《Clinical cardiology》1997,20(1):67-74
Catheter balloon angioplasty is a well accepted form of nonsurgical treatment of acutely and chronically obstructed coronary artery vessels. It is also the centerpiece for various new intervention techniques. Their morphologic effect on the site of obstruction has been termed “remodeling.” Part V of this six-part series focuses on remodeling effects of balloon angioplasty on obstructed young (≤ 1 year) and old (> 1 year) saphenous vein bypass grafts. 相似文献
36.
Christopher B. O'Brien Barbara S. Henzel Larry Wolfe Karen Gutekunst Dilip Moonka 《Digestive diseases and sciences》1997,42(5):1087-1093
Reports suggest that response tointerferon-alpha therapy is influenced by both hepatitisC viral genotype and titer. Our aim was to determine ifdirect, automated, cycle sequencing of the PCR productfrom an HCV RNA detection assay could be used toreliably determine HCV genotype. In addition, theapproach was used to determine the HCV genotypedistribution in our patient population and to learn ifthere was a correlation between HCV genotype and RNAtiter that could be used to predict response totreatment. In all 143 consecutive patients were testedfor both HCV RNA titer and genotype. Automated, cycle sequencing of PCR product was highly effectiveand failed to yield a genotype in only 3 (2%) patients.The distribution of HCV genotypes was: 1a (40%), 1b(39%), 2a (2%), 2b (6%), 3a (4%). There were significant differences in the median HCV RNA titersbetween genotypes 1, 2, and 3. 6 High HCV RNA titers>4.4 × 106 copies/ml were only seenin genotype 1. However, the HCV RNA level should not beused as a surrogate marker of genotype because of a significantoverlap of titers within the genotypes. 相似文献
37.
The syndrome of senile gait 总被引:1,自引:0,他引:1
Summary Infrared computed stroboscopic photometry was used to quantify the kinematic profiles of walking in 10 elderly patients with symmetrical neurological disturbances of gait and in 19 age-matched neurologically healthy people. Clinical examination of the patients revealed similar profiles of walking even though their diagnoses were vascular dementia (2), normal pressure hydrocephalus (2), Alzheimer dementia with possible normal pressure hydrocephalus (2), mixed Alzheimer and vascular dementia (1), peripheral neuropathy (1), Alzheimer dementia with parkinsonian features (1), and un determined (1). Quantitatively, the patients' gait kinematics deviated greatly from control values, but these deviations were statistically attributable to reductions in stride. We suggest that many gait disturbances in elderly people are similar, regardless of etiology, because the characteristics of these gait disturbances are heavily veiled by nonspecific stride-dependent changes that comprise the syndrome of senile gait. 相似文献
38.
INAUGURAL ARTICLE by a Recently Elected Academy Member:From oligonucleotide shapes to genomic SELEX: Novel biological regulatory loops
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Larry Gold David Brown Yi-yuan He Timur Shtatland BrittaS. Singer Yan Wu 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(1):59-64
The SELEX method and oligonucleotide combinatorial chemistry discovery process yields high-affinity/high-specificity ligands for virtually any molecular target. Typically, the enormous starting libraries used in the SELEX process contain 1014–1015 sequences. We now ask if the smaller sequences, complexity of extant organisms, and evolutionary history provide useful interactions between oligonucleotides and at least some unexpected targets. That is, do organisms contain a robust “linkage map” between their oligonucleotides and proteins and/or small molecules that enriches life? 相似文献
39.
Antiviral immune responses modulate the nature of central nervous system (CNS) disease in a murine model of multiple sclerosis 总被引:4,自引:0,他引:4
Summary: In animals and in humans, T-cell therapy can cure advanced disseminated leukemia that would otherwise be fatal. The therapeutic effect of immune T cells is quantitative. As the dose of effector T cells is increased, survival is proportionately increased. Therefore, effective T-cell therapy is predicated on the ability to procure large numbers of immune effector T cells. By using cultured T cells, the number of immune T cells can be increased in vivo substantially above che level achievable by vaccination. The survival of cultured T ceils in vivo is dependent upon both the culture conditions used and the therapeutic regimens employed. Under appropriate conditions, cultured T ceils can proliferate in vivo in response to stimulation by antigen, distribute widely and survive long term to provide effector function and immunologic memory. Given that T cells recognize peptides. the need for immunization with tumor can be circumvented by immunization with peptide. Peptide-specific T cells and the progeny of single T-cell clones can provide the necessary cellular functions to eradicate disseminated murine leukemia. The ability of cloned T cells to similarly provide substantial measurable immunity in humans has been validated in clinical trials. By priming with peptides and by using established culture conditions, T-cell therapy can now be directed against virtually any antigen within the host T-cell repertoire. The major remaining question to be answered is which proteins and which peptides are the most suitable targets for T-cell therapy trials. 相似文献
40.
Larry E. Davis Mario Kornfeld Herbert S. Mooney Kurt J. Fiedler Kathleen Y. Haaland William W. Orrison Elsa Cernichiari Thomas W. Clarkson 《Annals of neurology》1994,35(6):680-688
For 3 months in 1969 a family in the United States that included a pregnant mother consumed pork containing methylmercury. Children, aged 20, 13, and 8 years and a neonate, developed severe neurological signs. Twenty-two years later, the 2 oldest had cortical blindness or constricted visual fields, diminished hand proprioception, choreoathetosis, and atentional deficits. Magnetic resonance images showed tissue loss in the calcarine and parietal cortices and cerebellar folia. The youngest had quadriplegia, blindness, and severe mental retradation until their deaths. The brain of the 8-year-old who died at age 30 showed cortical atrophy, neuronal loss, and gliosis, most pronounced in the paracentral and parietooccipital regions. The total mercury level in formalin-fixed, left occipital cortex was 1,974 ng/gm as measured by atomic absorption. Regional brain mercury levels correlated with extent of brain damage. A control patient had 38.5 ng of mercury/gm in the occipital cortex. Systemic organs in the patient and a control subject had comparable mercury levels. In mercury-intoxicated rats, we found that only 5 to 10% of total brain mercury was lost by formalin fixation. Brain inorganic mercury in the patient ranged from 82 to 100%. Since inorganic mercury crosses the blood-brain barrier poorly, biotransformation of methyl to inorganic mercury may have occurred after methylmercury crossed the blood-brain barrier, accounting for its persistence in brain and causing part of the brain damage. 相似文献