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11.
Background. Partial harvesting of the left internal mammary artery (LIMA) is a widespread technique used during minimally invasive coronary operations performed through a left anterior small thoracotomy. The influence of persisting LIMA branches was investigated to evaluate their effect on the blood flow of the left anterior descending artery.

Methods. Thirty patients, 15 with totally (group A) and 15 with partially (group B) harvested LIMAs, were evaluated. All the patients underwent postoperative angiography, during which a flow map of the LIMA was performed. The average peak velocity and the diastolic-to-systolic peak velocity ratio were recorded. The LIMA graft flow pattern was recorded in the proximal and distal thirds of the artery. Intramammary adenosine (12 to 14 μg) was injected and the average peak velocities before and after injection were calculated.

Results. The average peak velocity was similar in both groups in the proximal and distal thirds of the LIMA (25 ± 7 and 26 ± 5 cm/sec, respectively, in group A versus 27 ± 5 and 25 ± 5 cm/sec, respectively in group B; p = NS). The diastolic-to-systolic peak velocity ratio was similar proximally (0.78 ± 0.3 in group A versus 0.69 ± 0.3 cm/s in group B; p = NS), but not distally (1.72 ± 0.1 in group A versus 0.97 ± 0.3 in group B; p < 0.0005). The LIMA graft flow reserve was similar both proximally and distally (2.6 ± 0.6 and 2.5 ± 0.3 cm/s, respectively, in group A versus 2.6 ± 0.5 and 2.6 ± 0.3 cm/s, respectively, in group B; p = NS).

Conclusions. The persistence of LIMA branches does not influence the blood flow of the left anterior descending artery after acute adenosine-induced myocardial hyperemia. If a left anterior small thoracotomy is used in left anterior descending artery direct revascularization, complete LIMA harvesting is not mandatory and depends on the personal preference of the surgeon.  相似文献   

12.
The clinical and biochemical presentation of carcinoma of the pancreas (PC) and of the papilla of Vater (CPV) are very similar, and, consequently, detailed investigations are required to correctly distinguish between them. The aim of the present study was to select the clinical and biochemical variables that would most efficiently discriminate the precise site of tumor origin. The study group consisted of 72 patients with PC and 22 patients with CPV consecutively hospitalized in our department. The following clinical parameters were considered: age, asthenia, anorexia, vomiting, weight loss, pain, fever, pruritis, and constipation; the biochemical parameters considered were total, direct, and indirect bilirubin, glucose, alkaline phosphatase, gamma glutamy transferase, transaminase, total protein, amylase, and occult blood in stools. The results indicated that in the initial phase of PC the most frequent clinical parameters were weight loss (P<0.0001), anorexia (P<0.02), constipation (P<0.001), and pruritus (P<0.01). In contrast, in CPV, fever (P<0.003) was most frequent in the same phase. There was a statistically significant difference in occult blood in stools (P<0.0001), total (P<0.03) and direct bilirubin (P<0.02), alkaline phosphatase (P<0.05), and transaminase (P<0.002) values in the two groups. On discriminant analysis, weight loss, constipation, pruritus, nausea, anorexia, and fever were the variables which best discriminated between the two types of tumors. In fact, the presence of weight loss, anorexia, asthenia, constipation, and pruritus correctly classified 87.5% of the patients with PC, while the presence of fever and nausea correctly classified 72.7% of the patients with CPV.  相似文献   
13.
The case describes a 38-year-old woman presenting a multilocular radiolucency affecting the entire right half of the lower jaw, with an unerupted third molar displaced to the region of the coronoid process. The histological study showed the presence of fibroblasts, focally with pleomorphic nuclei, dense collagen and an odontogenic epithelium with dystrophic calcifications. A cyst with an important inflammatory infiltrate was, moreover, observed.  相似文献   
14.
The ability of the aminothiol N-acetylcysteine (NAC) to preventthe formation of carcinogen-DNA adducts in tracheal epithelialcells was investigated in Sprague-Dawley rats exposed whole-bodyto mainstream cigarette smoke for either 40 or 100 consecutivedays. 32P-Postlabelling analyses showed the occurrence of DNAadducts (12.49 adducts/108 nucleotides) after 40 days of exposure,with a trend to formation of characteristic diagonal radioactivezones. Total adduct levels were not further enhanced after 100days of exposure to smoke, although significant changes occurredin the amounts of individual adducts. NAC, given by gavage inthe 40 day study and in drinking water in the 100 day study,significantly inhibited the formation of smoke-related carcinogen-DNAadducts in the tracheal epithelium, to such an extent that adductlevels were not significantly higher than those detected insham-exposed control rats. Together with a variety of othermolecular, clastogenicity, metabolic, cytological and histopathologicalend-points investigated in rodents and with the preliminaryevidence arising from a study in humans, these results documentthe considerable efficacy of oral NAC in inhibiting smoke-relatedcarcinogen-DNA adducts.  相似文献   
15.
16.
OBJECTIVE: We describe the case of a patient who developed an episode of catatonia during the course of her life-long obsessive-compulsive disorder (OCD) and discuss issues related to the etiopathogenesis, differential diagnosis, and therapeutic management of this association. BACKGROUND: Catatonia is conventionally considered a heterogeneous syndrome of motor dysregulation characterized by mutism, immobility, negativism, posturing (catalepsy), stereotypies, and echophenomena. The relationship between OCD and catatonia is still misunderstood and poses significant challenges to the diagnosis and treatment of patients with both conditions. METHOD: Naturalistic follow-up of a single case. RESULTS: A patient with OCD developed catatonia in concert with deteriorating mood, thought, and behavior. This atypical clinical presentation of individuals with OCD and the list of differential diagnosis raised during the patient's clinical assessment are discussed on 3 different levels: symptomatic presentation, comorbidity pattern, and pharmacodynamic mechanisms involved. CONCLUSIONS: The development of a systematic therapeutic plan for patients with OCD and comorbid catatonia includes: the fine-tuning of the antiobsessional treatment; management of comorbid disorders that may engender catatonia; prompt discontinuation, and subsequent slow reintroduction of drugs deemed to trigger toxic reactions or to worsen comorbid disorders and, ultimately, the catatonia; and the implementation of specific anticatatonia measures.  相似文献   
17.
Mycobacterium avium subsp. paratuberculosis (MAP) is the etiological agent of Johne's disease (JD), a chronic gastroenteritis of ruminants and other animals, including primates. Many evidences suggested association of MAP to Crohn's disease, a chronic granulomatous gastrointestinal disease of humans with strong similarities with JD. The present study attempts to evaluate global gene regulation in MAP, which has not been addressed previously, despite the availability of MAP genome sequence. For this purpose, we investigated: (i) the presence of sigma factors and their relationship to sigma factors of other mycobacteria (M. avium subsp.avium, M. tuberculosis, M. bovis, M. leprae and M. smegmatis), and (ii) their expression during different growth conditions and in vitro infection of intestinal epithelial Caco2 cells. MAP genome contains 19 putative sigma factor, but only 12 belong to gene families common to other mycobacteria. Gene expression was evaluated with Real-Time PCR during growth in 7H9 medium and mycobactin J, in 7H9 medium plus mycobactin J and lisozyme, and during infection of Caco2 cells: very different expression patterns were observed and, on the whole, only 7 sigma factors were found to be expressed. sigJ was upregulated during the infection of Caco2 cells. Even if only few sigma factors were expressed in the three conditions tested, the overall high numbers of MAP sigma factors suggests a noteworthy flexibility of this pathogen. Thus, this first report on expression of MAP sigma factors opens the way to an extensive characterization of global gene regulation, as a key to understand strategies of survival and mechanisms of infections used by this organism.  相似文献   
18.
19.
To compare rest-injected thallium-201 (Tl) redistribution and resting technetium-99m methoxyisobutylisonitrile (99mTc-MIBI) myocardial uptake in chronic coronary artery disease (CAD), 15 patients with angiographically proven CAD and left ventricular (LV) dysfunction (ejection fraction 34%±9%) were studied. All patients underwent rest-redistribution Tl and resting 99mTc-MIBI cardiac imaging. Gated 99mTc-MIBI images were also acquired to assess regional LV wall motion (WM). Myocardial segments (n=225) were divided into three groups on the basis of the degree of coronary artery stenosis: group 1 (total occlusion, n=82), group 2 (50%–99% of stenosis, n=84) and group 3 (<50% of stenosis, n=59). WM was significantly worse in groups 1 and 2 compared to group 3 (P<0.001), but no difference was observed between groups 1 and 2. TI and 99mTc-MIBI uptake were significantly lower in groups 1 and 2 compared to group 3 (P < 0.001), and in group 1 compared to group 2 (P<0.001). When TI and 99mTc-MIBI uptake were directly compared, TI uptake was higher than 99mTc-MIBI uptake in group 1 (P<0.001), while no significant difference was observed in groups 2 and 3. Thus, both rest-injected TI redistribution and resting 99mTc-MIBI uptake reflected the severity of coronary artery stenosis in CAD. However, in myocardial segments with total coronary occlusion T1 uptake was significantly higher than 99mTc-MIBI uptake. Our data suggest that rest-injected Tl redistribution cardiac imaging may identify, more accurately than resting 99mTc-MIBI imaging, the presence of viable myocardium in chronic CAD, particularly when the coronary blood flow is severely impaired.  相似文献   
20.
In the course of a phase I trial, in which recombinant IL-2 (rIL-2) was infused intraperitoneally (i.p.) in patients with peritoneal carcinomatosis, we evaluated the effect on "tumor-associated lymphocytes" (TAL) isolated from the ascitic fluid. No major changes in the percentages of cells expressing the CD3, CD4, CD8, Leu-7, OKM1 and WT-31 antigens were detected either in TAL or in peripheral blood lymphocytes (PBL) after 7 days of rIL-2 infusion. In contrast the percentages of TAL (but not PBL) expressing surface IL-2 receptor (Tac), or LAK-1 antigen were sharply increased. Analysis of cytolytic functions showed a potentiation of the lytic activity against natural-killer (NK) sensitive K562 target cells and the de novo appearance of lytic activity against fresh melanoma cells. In one patient IFN-gamma was detected in the ascitic fluid following rIL-2 infusion. T-cell clones derived from the patient were analyzed for the IFN-gamma production. While only approximately 40% of PB-derived control clones produced medium to low amounts of IFN-gamma, all of the TAL-derived clones produced medium to high amounts of the lymphokine.  相似文献   
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