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71.
BACKGROUND: Murine progressive ankylosis (MPA) is a spontaneous arthropathy that produces ankylosis of peripheral and spinal joints in mice homozygous for the gene ank. This animal model bears a striking resemblance clinically, radiographically, and histologically to ankylosing spondylitis. Phosphocitrate (PC) is the only treatment known to significantly delay disease progression in MPA. Transforming growth factor-beta (TGF-beta) is important for both developmental bone formation and fracture healing, and has been detected in biopsy specimens from sacroiliac joints of patient with ankylosing spondylitis. We hypothesized that TGF-beta might be involved in the pathogenesis of MPA. METHODS: We compared the proliferative response of resting fibroblasts from normal and MPA mice to TGF-beta 1 as measured by 3H-thymidine incorporation and the effect of PC on that response. Cells were cultured with 10% serum as a positive control. The mouse fibroblast cell line, BALB/3T3, controlled for culture conditions. RESULTS: MPA and normal fibroblasts responded similarly to serum. MPA fibroblasts proliferated significantly better in TGF-beta 1 than the poorly responsive normal mouse fibroblasts. PC, at 10(-3) mol/L, inhibited the TGF-beta 1-induced proliferation of MPA and 3T3 cells, but had no effect on normal fibroblasts. CONCLUSIONS: MPA fibroblasts proliferate excessively to TGF beta 1 in vitro. This effect could be caused by altered TGF receptors, changes in signal transduction, or impaired inhibition of the TGF-beta signal. This excessive response is blocked by PC. These results give further clues as to how PC inhibits the progression of ankylosis in MPA.  相似文献   
72.
Three hepatic porphyrias--acute intermittent porphyria, hereditary coproporphyria and variegate porphyria--are characterized by episodic acute attacks that consist of various neuro-psychiatric symptoms and signs, such as abdominal pain, vomiting, constipation, hypertension and tachycardia associated with increased excretion of porphyrins and porphyrin precursors. Peripheral neuropathy is manifested as pain in the extremities, and it may progress to a severe motor neuropathy. Measurement of porphobilinogen in the urine gives a prompt diagnosis during acute attacks. Attacks are often induced by precipitating factors such as drugs, alcohol, infection, fasting or changes in sex-hormone balance, and they should be eliminated when a patient is treated during an attack. Heme, the end biosynthetic product, is the most effective therapy for restoration of porphyrin biosynthesis to normal, and it is usually infused at 3 mg/kg daily for 4 days. Adequate calories are necessary and parenteral nutrition with carbohydrates may be necessary. Attacks may also require therapy for hypertension, pain and epileptic seizures. Strict avoidance of all precipitating factors may not be necessary in the asymptomatic phase.  相似文献   
73.
Alcaligenes xylosoxidans is an uncommon but serious cause of nosocomial epidemics. This report describes a cluster of two patients who underwent revision of hip arthroplasties and one patient who had a lumbar puncture. Cultures obtained during all three procedures showed A. xylosoxidans with similar antibiotic sensitivity patterns. An investigation found that saline used to process these specimens was contaminated with this organism.  相似文献   
74.
PURPOSE: The technique and outcome of minimally invasive laparoscopic treatment of various forms of intussusception in children after ineffective attempt at conservative treatment are described. METHODS: Ninety-eight patients from 2 months to 11 years of age were analyzed. RESULTS: Suggested scheme of surgical treatment using laparoscopic technique was successful in 64 patients (65.3%), and conversion to open procedure occurred in 34 (34.7%). There was no mortality or intraoperative complications in our series. CONCLUSION: Practically every form of intussusception without bowel necrosis, including the most complex forms, can be reduced now using modern videolaparoscopic equipment and atraumatic instruments.  相似文献   
75.
OBJECTIVE: Esophageal adenocarcinoma is increasing in white men. We sought to identify trends in esophageal cancer in different patient groups in our region. METHODS: We reviewed the records of all patients with esophageal cancer seen at two hospitals in Columbia, SC between 1981 and 1995. Patients were divided into three cohorts (1981-1985, 1986-1990, and 1991-1995). Demographic data, histological type, tumor stage, grade, and survival were recorded. RESULTS: Histology was available in 371 of 386 patients (cohort 1, 113 patients; cohort 2, 144; and cohort 3, 114). Adenocarcinoma accounted for 24%, 27%, and 49% of esophageal cancer in white men in cohorts 1, 2, and 3, respectively (p = 0.03). Corresponding figures for African-Americans were 10%, 7%, and 3% (p = 0.22). Women comprised 8%, 14%, and 22% of patients with squamous carcinoma in the three cohorts (p = 0.03). Median survival for esophageal cancer was 6.0, 6.8, and 10.4 mo in cohorts 1, 2, and 3 (p = 0.0002). CONCLUSION: Adenocarcinoma is increasing in whites. Squamous carcinoma remains the predominant type in this region, seen mainly in African-Americans. Esophageal squamous carcinoma is increasing in women. The mean age at diagnosis of squamous carcinoma has decreased in whites. There is a trend toward improved survival in patients with esophageal cancer.  相似文献   
76.
Using intraoperative monitoring of the blood flow linear speed in a. cerebralis media while total a. carotis interna occlusion in 10 patients the authors have concluded, that the degree of blood flow compensation in a. cerebralis media depends not only on collateral compensation possibilities by the contralateral side and rate of it inclusion, but largely-on a. carotis externa possibility on the lesion side.  相似文献   
77.
Normally the rat gingival microcirculatory bed is represented by superficial capillaries, postcapillaries, arterioles, and venules of different diameters. The major changes characterizing microcirculation disorders in experimental periodontitis are edema, arteriolar constriction and dilatation, stasis, and thrombosis, which undergo variously directed shifts in different periods of pathological process.  相似文献   
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79.
The lipoxygenase pathway in sunflower roots was studied in vitro. A preliminary incubation of linoleic acid with 15 000 g supernatant of homogenate of sunflower roots (1.5-6 days after germination) revealed the predominant activity of 13-lipoxygenase. The exogenously added linoleic acid 13-hydroperoxide is further utilized through two competing pathways. One of them is directed towards formation of the ketodiene (9Z,11E)-13-oxooctadeca-9,11-dienoic acid. The second pathway, which is controlled by allene oxide synthase, leads to the formation of an alpha-ketol and a novel cyclopentenone, rac-cis-12-oxo-10-phytoenoic acid (12-oxo-PEA) via a short-lived allene oxide. Unexpectedly, the cyclopentenone 12-oxo-PEA is the predominant allene oxide synthase product. Identification of cis-12-oxo-PEA was confirmed by its UV, mass, (1)H NMR and 2D-COSY spectral data. The highest yield of 12-oxo-PEA is observed in very young roots (1.5-2 days after germination). The results of methanol-trapping experiments demonstrate that both 12-oxo-PEA and alpha-ketol are formed through the unstable allene oxide intermediate, (9Z)-12,13-epoxyoctadeca-9,11-dienoic acid, which is the primary product of allene oxide synthase. Since 12-oxo-PEA is a jasmonate congener, its biosynthesis in plants might be of physiological importance.  相似文献   
80.
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