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81.
Antonio Cuadrado Emilio Fábrega Fernando Casafont Fernando Pons-Romero 《Liver transplantation》2005,11(4):420-426
The aim of this study was to evaluate the rate of alcohol recidivism after orthotopic liver transplantation (OLT) for alcoholic liver disease (ALD) and its influence on the allograft and patient survival, as well as the development of comorbidities and de novo cancers. The study was performed on 54 subjects previously analyzed and transplanted in our center for ALD, whose follow-up was prolonged to a mean of 99.2 (SD 31.7) months (range, 14-155). Medical records were reviewed, and data on alcohol consumption, therapeutic compliance, graft evolution, rejection, infections, comorbidities, rates of de novo malignancies and other clinical events, and survival were collected. Comparisons between groups were performed by the Fisher's exact test, and survival was assessed by the Kaplan-Meier method. Survival curves were compared using the Mantel-Cox statistic. The risk of death resulting from alcohol recidivism was analyzed with a Cox proportional hazards model. Fourteen patients who underwent transplantation for ALD (25.9%) returned to alcohol use between 5.0 and 86.9 months after OLT (median, 47.5). There was no significant association between the presence or absence of alcohol recidivism and the occurrence of graft rejection, infections, associated comorbidities after OLT, or compliance. The 5- and 10-year survival rates for patients with alcohol recidivism were 92.9% and 45.1%, respectively, compared with 92.4% and 85.5%, respectively, for patients without alcohol recidivism. These figures show significantly lower survival rates in recidivistic patients after 10 years (P < 0.01, Mantel-Cox). The fact that patients who resumed alcohol consumption have a worse 10-year survival rate might be attributed to a higher frequency of deaths, primarily from cancer and cardiovascular events. 相似文献
82.
The role of glutamate in conditioned taste aversion was investigated. Both, in the amygdala (AMYG) and in the lateral hypothalamus (LH) extracellular levels of glutamate were assessed by microdialysis and capillary electrophoresis with laser induced fluorescence detection. Rats were conditioned by pairing a novel flavor (strawberry flavor) with an intraperitoneal injection of lithium chloride. When the conditioned stimulus (strawberry flavored solution) was injected into the mouth of conditioned rats, there was an increase of glutamate release in the AMYG, and a decrease in glutamate release in the LH. These results predicted that glutamate release in the AMYG and the LH was involved in CTA. This possibility was tested by MK-801 (glutamate antagonist) and glutamate microinjections. MK-801 injections in AMYG attenuated the rejection of the novel flavor, and in the LH did not cause any effect on CTA. Glutamate microinjections in the AMYG caused CTA. These results suggest that glutamatergic activity in the AMYG might be a relevant neurochemical correlate and cause of conditioned taste aversion. 相似文献
83.
PURPOSE: To assess the dose-dependent effect of low concentrations of isoflurane on respiratory mechanics in normal subjects. METHODS: We studied 12 non-premedicated ASA I patients scheduled for lower abdominal or extremity surgery. After thiopental 5-7 mg*kg(-1) iv and succinylcholine 1 mg x kg(-1) iv, the trachea was intubated and an esophageal balloon was placed optimally by the occlusion test. After introduction of N(2)O and muscle paralysis with vecuronium, we studied 0, 0.6, 0.9 and 1.2% isoflurane. We recorded flow (F), airway opening and esophageal pressures. Signals were amplified, filtered, sampled at 100 Hz, and then fed in a 12-bit analogue-digital converter in a personal computer. Data were collected and analyzed using LABDAT and ANADAT software. Signals were acquired for 60-90 sec during mechanical ventilation (10 mL x kg(-1), 10 breaths x min(-1), I:E ratio 1:2). We estimated respiratory system (RS), lung (L) and chest wall (W) dynamic elastance (E) and resistance (R) by P(t) = EV(T)(t) + RF(t) + K, where t is time, V(T) tidal volume from integration of F, and K an estimation of end-expiratory pressure. ANOVA was used for comparing the basal state with the three concentrations. RESULTS: E and R were statistically lower at 0.6, 0.9 and 1.2% compared to basal values for RS, L and W. Concentrations equal to or higher than 0.6% did not further change respiratory mechanics, except for E(L1.2) compared to E(L0.6,) 12.37 +/- 5.72 and 13.52 +/- 5.64 cm H(2)O.L(-1), respectively. CONCLUSION: Isoflurane concentrations between 0.6-1.2% are not associated to a dose-dependent effect on respiratory mechanics. 相似文献
84.
Invariant Visual Responses From Attentional Gain Fields 总被引:5,自引:0,他引:5
85.
Dr. Pedro J. Morgado M.D. José A. Suárez M.D. Luis G. Gómez M.D. Pedro J. Morgado Jr. M.D. 《Diseases of the colon and rectum》1988,31(6):474-480
The present classification of first, second, and third grade hemorrhoids only reflects variation in size of a normal human tissue and does not relate to "hemorrhoidal disease." Cross-sections and coronal sections of the anal canal in 32 fetuses, with ages ranging from 28 to 38 weeks of development, were studied and the following fundamental facts were found: in the lumen of the anal canals of fetuses, there are prominences of mucosa formed by conjunctive and muscular tissue, arterial and venous vessels and glands, arranged without following any particular pattern, which resemble similar formations found in the adult that protrude equally in the inside of the canal, known as hemorrhoids. The muscular tissue, smooth or striated, is grouped in bundles, and bunches of collagen fibers of homogeneous, nonfragmented, and regular aspect are found between them. Blood vessels have an ample lumen with a defined structure of collagen tissue as well as muscular tissue in its walls. Prominences of mucosa are connected to the remainder of the intestinal wall by defined conjunctive thick, nonfragmented fibers, that permit firm adherence. In healthy adults, the findings were similar but there was an evident degenerative process in the collagen fibers. In 100 surgical specimens of hemorrhoidectomies, the histologic investigation demonstrated a severe inflammatory reaction that especially affected the blood vessel wall and conjunctive tissue, which probably produced an ischemic lesion of the mucosa that could condition the onset of a vascular thrombosis, allowing displacement of the mucosa and its protrusion through the anus. The files of 815 patients suffering from hemorrhoidal disease were also studied. The main physical findings were bleeding, thrombosis of the internal hemorrhoidal plexus, prolapse of the anal cushions, or a combination of these. The authors propose to classify hemorrhoidal disease as bleeding, prolapsing, thrombotic, and mixed hemorrhoidal disease, aiming toward a rational treatment. 相似文献
86.
Heredia García Carlos Dante García Calderon Pedro Antonio 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1988,226(5):428-430
One hundred patients with retinal detachment (61 primary operations and 39 reoperations) were studied for titers of autoantibodies to human retinal S antigen using the enzyme-linked immunosorbent assay technique (ELISA). There was no statistically significant difference when comparing the group of patients with primary retinal detachment with the control group. However, a statistically significant increase in anti-S titers was recorded when a comparison was made between the group of reoperated patients and the control group (2,P < 0.001) and between the group of reoperated subjects and the group of patients operated on for the first time (2,P < 0.005).Presented at the XVth Meeting of the Club Jules Gonin, Copenhagen, 10–15 August 1986 相似文献
87.
Summary In the 4th International Workshop on Chronic Lymphocytic Leukaemia (CLL), staging and response criteria were proposed to help physicians make decisions on when and how to treat patients with CLL. The most important factor is prolonging survival. There are several promising new treatment approaches under investigation, and the criteria proposed should facilitate future therapy trials.Supported in part by grants 89-0353 (Fondo de Investigaciones Sanitarias de la Seguridad Social), PA 85-0234 and PB 86-0593 (Dirreción General de Investigación Científica y Técnica), Ministerio de Educación y Ciencia 相似文献
88.
Emilio Benfenati Pierluigi Farina Tina Colombo Gianluca De Bellis Mauro Valerio Capodiferro Maurizio D'Incalci 《Cancer chemotherapy and pharmacology》1989,24(6):354-358
Summary The pharmacokinetics of the anticancer agent p-(3,3-dimethyl-1-triazeno) benzoic acid (pCOOH-DMT), a drug now in phase I clinical trial in Europe, was investigated in C57 Bl female mice with M5076 reticulum-cell sarcoma that were treated i.v. with 200 mg/kg pCOOH-DMT. The drug disappeared from plasma with a terminal half-life of about 2.5 h. Plasma clearance was approximately 6 ml/min per kg. Distribution studies showed some differences in drug levels in different tissues. The highest levels were found in the tumor, liver, kidney and lung; lower levels were found in the spleen and gut, and the lowest, in the brain. The N-desmethyl derivative of pCOOH-DMT was not detectable in plasma or tissues of mice treated with the drug. Therefore, the previous evidence of low N-demethylation of pCOOH-DMT was confirmed. pCOOH-DMT glucuronide was identified by mass spectrometry and quantified by high-performance liquid chromatography (HPLC) in plasma, tissues and urine samples. pCOOH-DMT glucuronide appears to be the major urinary metabolite of pCOOH-DMT in mice. Another metabolite identified by mass spectrometry and quantified by HPLC in some tissues and urine was pCOOH-DMT glycinate.Abbreviations DTIlC
5-(3,3-dimethyl-l-triazeno)imidazole-4-carboxamide
- pCOOH-DMT
p-(3,3-dimethyl-l-triazeno)benzoic acid
- pCOOH-MMT
p-(3-methyl-l-triazeno)benzoic acid
- pCONH2-DMT
p-(3,3-dimethyl-l-triazeno)carboxamide
- BSTFA
N,O-bis(trimethylsilyl)trifluoroacetamide
- TMCS
trimethylchlorosilane
- TLC
thin-layer chromatography
- FAB
fast atom bombardment
- EI
electron impact
- M5
M5076 reticulum-cell sarcoma
- t1/2
beta-half-life
- C0
concentration time 0
- AUC
area under the concentration vs time curve
- Cl
total clearance
- V
volume of distribution 相似文献
89.
Busse A Sánchez MA Monterroso V Alvarado MV León P 《American journal of medical genetics. Part A》2004,(2):190-194
Four affected siblings in a Costa Rican family presented an aggressive polyneuropathy with widespread involvement of many visceral organs and onset during the third decade of life with rapid loss of muscle mass in the lower limbs and severe dysautonomy. The medical histories include vitreous opacity, cardiac enlargement, dermal and gastrointestinal infiltration, and autonomic dysfunction including circulatory compromise and gastrointestinal disturbances. Histological studies using Congo red stain and immunohistochemical assays with antibodies against the transthyretin (TTR) protein showed widespread deposition of amyloid in extracellular areas, including dermis and gastrointestinal lamina propia, endo- and perineural spaces, and vascular walls. A mutation search in the transthyretin (ttr) gene was performed seeking the cause of this severe form of familial amyloidotic polyneuropathy (FAP). We applied single-stranded conformational polymorphism (SSCP)-analyses followed by sequencing of the four exons of the ttr gene, revealing a point mutation in exon 3, a G to A transition that causes a Glu54Lys codon change. Western blots of plasma proteins incubated with anti-transthyretin antibodies after gel electrophoresis provided separation of wild-type and mutant TTR protein in affected family members. 相似文献
90.
Well-differentiated endometrial adenocarcinoma can be difficult to distinguish from complex atypical hyperplasia (CAH) in a curettage or biopsy specimen. When a focus of back-to-back glands or cribriforming smaller than 2.1 mm is seen in a biopsy, we make a diagnosis of adenocarcinoma in situ (AIS). Whether this diagnosis translates into a more frequent diagnosis of carcinoma on the hysterectomy specimen is unknown. The objective of this study was to compare follow-up hysterectomy findings in biopsies showing AIS in CAH with biopsies showing only CAH without AIS. Twelve biopsy/curettage cases diagnosed as endometrial AIS in CAH and 12 biopsy/curettage cases diagnosed as CAH only were reviewed and correlated with corresponding hysterectomy material. A diagnosis of AIS was designated on biopsy/curettings when a focus of back-to-back glands or cribriforming less than 2.1 mm was present. Hysterectomy specimens showed endometrial carcinoma in 6 (50%) of 12 cases of CAH with AIS, and in 2 (17%) of 12 cases diagnosed as CAH only. Endometrial carcinoma with myometrial invasion was identified in 5 (42%) of the cases showing AIS on biopsy, but in none of the 12 cases diagnosed as CAH only on biopsy. Identification of AIS in CAH cases provides useful prognostic information. 相似文献