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91.
Premalignant lesions and nonsquamous malignancy of the penis and carcinoma of the scrotum. 总被引:2,自引:0,他引:2
P F Schellhammer G H Jordan E L Robey J T Spaulding 《The Urologic clinics of North America》1992,19(1):131-142
Premalignant lesions of the penis include cutaneous horn, balanitis xerotica obliterans, and leukoplakia. The true incidence of progression of each of these to squamous-cell carcinoma is unknown. Bowenoid papulosis, erythroplasia of Queyrat, and Bowen's disease are histologically identical to in situ carcinoma. Although the first is consistently benign, the latter two regularly evolve into invasive cancer. Malignant scrotal lesions include squamous-cell carcinoma, liposarcoma, leiomyosarcoma, basal-cell carcinoma, extramammary Paget's disease, erythroplasia of Queyrat, malignant melanoma, and metastases. Hemangioma can be confused with carcinoma. 相似文献
92.
Mild traumatic brain injury in an insured population: subjective complaints and return to employment 总被引:5,自引:0,他引:5
The great majority of traumatic brain injury (TBI) is of mild severity, with Glasgow Coma Scores (GCS) of 13-15, post-traumatic amnesia of less than 48 hours and brief, if any, hospitalization. All mild TBI admissions to hospital were provided with education in the form of a brief interview and a brochure on minor head trauma from the National Head Injury Foundation. Seventy-seven insured individuals with mild TBI were contacted by phone between 1 and 3 months post-injury to determine the frequency and severity of post-traumatic symptoms and the rate of return to work (RTW). Twenty-six per cent of those contacted had subjective complaints; 88% had returned to work or school; 16% of those returning did so with some symptoms. Only 45% of symptomatic individuals sought medical consultation for their condition when offered. Education about post-traumatic symptoms from the onset may provide sufficient reassurance to most individuals that future use of medical services is seen as unnecessary. Rate of RTW is relatively higher than reported in previous studies of mild TBI. 相似文献
93.
Van Landeghem G; Haese P; Lamberts L; Barata J; DeBroe M 《Nephrology, dialysis, transplantation》1997,12(8):1692-1698
Background: The association between aluminium and
dialysis encephalopathy and deterioration of the neurological state during
desferrioxamine treatment of dialysis patients is well established. At
present little is known about the speciation and the mechanisms underlying
the element's neurotoxicity. Methods. Aluminium speciation was performed in
cerebrospinal fluid samples of acutely aluminium-intoxicated dialysis
patients using a recently developed high-performance liquid
chromatographic/electro-thermal atomic absorption spectrometric hybrid
method. Results: Baseline cerebrospinal fluid
aluminium levels of samples taken shortly after the intoxication were low
but elevated (5.0±2.0 &mgr;g/l, n=3) as compared to subjects
with normal renal function (<1 &mgr;g/l). In contrast to the
situation noted in serum and to the iron speciation in cerebrospinal fluid,
aluminium was not bound to transferrin but appeared as two distinct
compounds, the main fraction eluting at the elution volume of aluminium
citrate/silicate. The second compound was not identified. Forty-four hours
after desferrioxamine administration the cerebrospinal fluid aluminium
levels had increased up to a concentration of 10.3±2.5
&mgr;g/l (n=3). This was accompanied by a change in the speciation
profile with aluminium appearing at the elution volume of aluminoxamine.
Conclusion: Our findings may contribute to a better
understanding of the neurotoxic effects of aluminium and its
desferrioxamine chelate in dialysis patients. 相似文献
94.
F. M. RAAPHORST R. LANGLOIS VAN DEN BERGH J. L. M. WAAIJER J. M. VOSSEN & M. J. D. VAN TOL 《Scandinavian journal of immunology》1997,46(3):292-297
Fetal B lymphocytes in mice and humans use a limited number of the available VH gene segments. Mouse fetal B cells primarily utilize 3' VH elements, suggesting that the localization of these elements determines their rearrangement frequency. The previously reported non-random usage of human VH genes has been more difficult to explain. In this study the authors analysed the expression of the most proximal 3' human VH element (VH 6) using a monoclonal antibody (JE-6). VH 6 expression was assessed in various B cell differentiation stages from fetal liver, bone marrow and spleen at 12–20 weeks of gestation. The authors demonstrate that the level of VH 6 expression does not exceed a stochastic usage frequency. This suggests that the localization of VH 6 does not significantly promote its expression during human fetal life, and that other factors must affect the usage of VH genes during human fetal development. 相似文献
95.
96.
Three hundred and twenty samples of subgingival plaque were obtained from 80 caucasian girls, ranging from 10 to 13 years of age. The samples were analyzed to verify the influence of age upon colonization of the gingival sulcus by microorganisms potentially pathogenic to the periodontal tissues. The gingival and plaque status were evaluated through the gingival index (GI) and plaque index (PlI) and the microflora was assessed by the enzymatic method benzoyl-arginine-naphthylamide (BANA). The results of the BANA test were positive for 62.50% of the tested individuals and 40% of the examined sites. The influence of age was statistically significant on BANA reactivity, and the number of positive sites was greater at 11 (57.5%) than at 12 years (28.8%). 相似文献
97.
Koichi Masuda Robert L Sah Michael J Hejna Eugene J-M A Thonar 《Journal of orthopaedic research》2003,21(1):139-148
Most attempts to tissue-engineer cartilage have involved seeding of cultured cells into a biological or synthetic scaffold. We have developed a novel two-step culture approach that makes possible the in vitro formation of cartilaginous-like tissue by mature adult bovine chondrocytes without the aid of a synthetic matrix. The first step consists of culturing chondrocytes under conditions that maintain their rounded shape and their molecular phenotype as assessed by type II collagen and aggrecan production. This step was accomplished by culturing the isolated chondrocytes in alginate beads until the cells have reestablished a proteoglycan-rich cell-associated matrix (CM). The second step consists of culturing the cells with their CM, after recovery from the beads, on a tissue culture insert with a porous membrane. In this study, young adult bovine articular chondrocytes were cultured in alginate beads in the presence of 10% or 20% fetal bovine serum (FBS). After 7 days of culture, the alginate beads were dissolved by incubating the beads for 20 min in sodium citrate buffer, a calcium chelator. Following a brief centrifugation, the cells with their CM were recovered, resuspended in medium containing 10% or 20% FBS and seeded onto a tissue culture insert. After 1 week of culture on the insert, the individual cells with their CM progressively became incorporated into a mass of cartilaginous tissue. Culture with 20% FBS resulted in the best formation of tissues. These tissues, easily recovered from the insert, were then subjected to biochemical and histological analyses. The biochemical results showed that the chondrocytes remain phenotypically stable in the tissues. The de novo tissue has a relatively high ratio of PG/collagen. Histological examination of the tissue revealed it contained a cartilage-like matrix strongly stained with toluidine blue. This scaffold-free system appears ideal to study, in vitro, the development of transplantable cartilaginous tissue. 相似文献
98.
L R Bergman 《Acta paediatrica Scandinavica》1991,80(12):1250-1252
99.
Most authors consider the principal advantage of FG anastomoses (compared to microsurgical anastomoses) to be shorter operating time, reduced surgical trauma to oviduct stumps, and absence of tissue ischemia. These features promote reparative regeneration and decrease adhesion formation, resulting in complete recanalization of fallopian tubes. To date, the majority of work on FG is confined to the experimental development of surgical techniques. Investigations in reconstructive gynecological surgery are quite uncommon. The physical properties of FG and the positive results of available experimental studies suggest that further development of surgical techniques using FG in obstetrics and gynecology is worthwhile. 相似文献
100.