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91.
The immunohistochemical and histochemical properties of 16 surgically excised subretinal neovascular membranes from 16 patients with age-related macular degeneration were studied. Primary antisera to c-retinaldehyde-binding protein; leukocyte common antigen; factor VIII-related antigen; S-100 protein; glial fibrillary acid protein; muscle-specific actin; neuron-specific enolase; collagen types I, II, III, IV, and V; laminin; and fibronectin were used for immunohistochemical characterization of the membranes. Histochemical staining for lipid and mucopolysaccharide was performed. The results of the staining in conjunction with histologic examination showed the cellular components of the membranes to be composed of retinal pigment epithelium, inflammatory cells, vascular endothelium, glial cells, myofibroblasts, photoreceptor cells, and fibrocytes. The extracellular matrix of the membranes contained collagen types I, III, IV, and V; fibronectin; laminin; mucopolysaccharide; and lipid. These findings are consistent with the concept that subretinal neovascular membranes in age-related macular degeneration are composed of localized intra-Bruch's membrane granulation tissue proliferation associated with diffuse drusen.  相似文献   
92.
Pathogenetic mechanisms in anterior proliferative vitreoretinopathy.   总被引:6,自引:0,他引:6  
A clinicopathologic study of ten consecutive patients (ten eyes) undergoing surgery for rhegmatogenous retinal detachment with anterior proliferative vitreoretinopathy and a subsequent histopathologic, immunohistochemical, and ultrastructural study of ten enucleated eyes with anterior proliferative vitreoretinopathy were performed in order to elucidate relevant pathogenetic mechanisms. Our findings suggest that the pathogenetic evolution of anterior proliferative vitreoretinopathy occurs in three consecutive stages: (1) traction on the ciliary body and peripheral retina induced by fibrocellular contraction of the vitreous base; (2) incorporation of tractionally denuded components of the ciliary body and peripheral retina into the fibrocellular membranes overlying the vitreous base; and (3) proliferation of the incorporated components and fibrovascular ingrowth from the uvea, the retina, or both, into the fibrocellular membranes. Tractional disruption of the epithelium of the ciliary body pars plicata and breakdown of the ciliary blood-aqueous barrier are the principal pathogenetic mechanisms of chronic intractable hypotony and the post-vitrectomy fibrin syndrome in anterior proliferative vitreoretinopathy.  相似文献   
93.
94.
引用违法传递概念设计合成了11个C-末端含氧代赖氨酸二肽,进行抗深部致病菌-白念珠菌活性试验,体外实验结果显示极强的抑菌活性,MIC在12.5~0.8μg/disk之间,较母体氧化赖氨酸大50~135倍(克分子比。  相似文献   
95.
Latency differences (>0.5 ms) of median and ulnar sensory action potentials (mSAP and uSAP) at the wrist evoked by ring finger stimulation are considered a sensitive and specific test for diagnosis of carpal tunnel syndrome (CTS). In this study, we aimed to assess the practical usefulness of the ring finger test (RFT) in routine electromyography (EMG) examinations. We investigated 2 series of patients: in the first prospective series we considered 300 hands affected by only mild CTS; in the second series we examined retrospectively the EMG charts of 961 hands affected only by CTS but not selected for severity or duration of symptoms. In the first series we found pathological RFT scores in 87% of cases, and pathological RFT or mSAP latency results in 92%. In the second series, pathological RFT scores were found only in 55% of cases, while in 20% where mSAP failed, a volume conducted uSAP had been erroneously interpreted as arising from the median nerve. RFT sensitivity tested in routine EMG examinations of unselected hands affected by CTS drops considerably. Fingers innervated by one only nerve, such as the index and the little fingers, must also be investigated to increase the diagnostic value of RFT.
Sommario La differenza (>0.5 ms) tra le latenze distali dei potenziali sensitivi di mediano e ulnare (mSAP e uSAP) registrati al polso ed evocati per stimolazione al quarto dito (ring finger test, RTF) viene considerato un test sensibile e specifico per la diagnosi di sindrome del tunnel carpale (CTS). Sono state studiate 2 serie di pazienti: nella prima serie prospettica abbiamo esaminato 300 mani affette da CTS lieve, in cui mSAP e uSAP dopo stimolazione al quarto dito potevano essere chiaramente differenziati. Il RFT era patologico nell'87%. Considerando insieme il risultato del RFT e il valore assoluto della latenza distale del mSAP dal quarto dito, almeno uno dei test era patologico nel 92% dei casi. Nella seconda serie sono stati esaminati retrospettivamente i referti EMG di 961 mani non selezionate affette esclusivamente da CTS. Attraverso il solo RFT solo il 55% delle diagnosi sarebbero state classificate correttamente, perchè in 20% un uSAP volume condotto era stato erroneamente interpretato come proveniente dal mediano. Dita innervate da un solo nervo come il secondo dito ed it quinto dito devono essere esaminate per aumentare il valore diagnostico del RFT in esami di routine.
  相似文献   
96.
97.
The objective of our study was to evaluate the sociodemographic factors associated with completion of screening for latent tuberculosis infection (LTBI) among undocumented immigrants in Brescia, Italy. Screening for LTBI was offered to 649 immigrants; 213 (33%) immigrants completed the first step of screening; only 44% (55/124) of individuals with a positive tuberculin skin test result started treatment for LTBI. The univariate analysis showed that being unmarried, of Senegalese nationality and being interviewed by a health-care worker with the same native language as the immigrant were significantly associated with completion of screening for LTBI. In the multiple logistic regression, being interviewed in the native language of the health-care worker (OR 2.5, 95% CI 1.3-4.8, P = 0.004) and being of Senegalese origin (OR 2.3, 95% CI 1.4-3.6, P = 0.0005) were independently associated with adherence to LTBI screening. Our results suggest that knowledge of the sociodemographic characteristics of immigrants, and the participation of health-care workers of the same cultural origin as the immigrant during the visits, can be an important tool to improve completion of screening for LTBI.  相似文献   
98.
OBJECTIVES: To determine the effect of deep-plane rhytidectomy on the cross-sectional area of the nasal cavity in the vicinity of the nasal valves and to compare this quantitative measure with patients' subjective assessment of their postoperative nasal airway. DESIGN: An inception cohort of 17 patients undergoing rhytidectomy (either cheek-lift or face-lift) for facial rejuvenation was evaluated with acoustic rhinometry. Initial measurements were taken approximately 1 week prior to surgery, followed by postoperative measurements at 1 week and again at 1 month (a total of 18 measurements per patient). Patients undergoing simultaneous nasal procedures were excluded. Control subjects consisted of patients undergoing facial plastic procedures other than rhytidectomy or septorhinoplasty (n = 3). The main outcome measure was cross-sectional area of both the internal and external valve regions as determined by acoustic rhinometry. The setting was an ambulatory surgery center at a large academic institution. RESULTS: Seventy percent of patients (12 of 17) reported subjective improvement of their nasal airway patency following rhytidectomy, whereas no control subjects (0%) reported any such change. Eighty-eight percent of patients (15 of 17) had a substantial increase in the dimension of their internal nasal valve area as measured with acoustic rhinometry at 1 week, with 70% of patients demonstrating increase at 1 month. Fifty-three percent of patients (9 of 17) demonstrated an increase in their external valve area at 1 week, and 59% had a persistent increase as measured at 1 month. No control subjects demonstrated any significant nasal valve area increases at either time. There was no correlation between age or body mass index and the measurement outcomes among participants. CONCLUSIONS: While there is a statistically significant increase in both the internal and external nasal valve cross-sectional areas at 1 month after rhytidectomy, the permanency of this effect is unknown. In support of these findings, a sizable proportion of patients undergoing rhytidectomy subjectively report an increase in their ability to breathe through their noses, lending credence to a postrhytidectomy melonasal effect.  相似文献   
99.
Myeloid sarcoma (MS) is a localized extramedullary mass of immature granulocytic cells that usually occurs in patients with acute myeloid leukemia (AML) or myeloproliferative disorders. It may rarely precede peripheral blood or bone marrow involvement, presenting a diagnostic challenge. Although MS may be found in any location, an intraoral occurrence is rare. In this report we describe a rare case of a patient with nonleukemic MS of the maxillary gingiva. The histologic specimen was first interpreted as non-Hodgkin's lymphoma. The correct diagnosis was reached after extensive immunohistologic studies. The malignant cells were myeloperoxidase positive, lysozyme positive, CD45+, CD68+, CD3-, CD10-, CD19-, CD20-, CD30-, CD34-, CD56-, CD79a-, S100-, and chloroacetate esterase negative. Induction therapy with FLAND (fludarabine, Ara-C, mitoxantrone, and dexamethasone) was started, but the patient did not achieve a remission. Some weeks later, the patient presented pleural effusion and paralysis of the seventh cranial nerve on the left side. She died a few days later. The present case indicates the importance of a correct initial diagnosis for adequate therapy, which is often delayed because of a high misdiagnosis rate. If the MS is treated without intensive chemotherapy for AML as soon as possible, the prognosis will be poor.  相似文献   
100.
As an alternative to performing interventional radiology on inpatients under the care of internists and surgeons, the authors have established a cardiovascular radiology admitting service for well-screened, elective patients. The patients are admitted under the care of a cardiovascular radiology fellow and a staff physician. From April 1982 to December 1983, 133 patients were admitted to the service. Patients are cared for in a surgical ward or in an intermediate unit, as determined by the clinical situation. Advantages of this approach include a broader patient referral base, improved rapport with clinical colleagues and patients, improved follow-up data, and rapid evaluation and treatment, resulting in short hospital stays. The major disadvantages involve the commitment of time and staff necessary to provide quality care. The concept of the interventional radiologist in the role of admitting physician has important implications in terms of negotiations for additional financial compensation, commensurate with the skill and time required for performing these procedures and caring for the patient.  相似文献   
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