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BACKGROUND AND OBJECTIVE: The purpose of this study was to determine whether solid material reinforcement of a liquid albumin solder coagulum could improve the cohesive strength of the solder and, thus, the ultimate breaking strength of the incision repair in vitro. STUDY DESIGN/MATERIALS AND METHODS: A 50%(w/v) bovine serum albumin solder with 0.5 or 2.5 mg/ml indocyanine green (ICG) dye was used to repair an incision in bovine aorta. The solder was coagulated with an 806-nm continuous wave diode laser. A 50-micrometer-thick poly(DL-lactic-co-glycolic acid) film was used to reinforce the solder (the controls had solder but no reinforcement). Acute breaking strengths were measured, and the data were analyzed by Student's t-test. RESULTS: Observations of the failure modes indicate cohesive strength reinforcement of the test specimens vs. the controls. The 2.5 mg/ml ICG reinforced solder was stronger than the controls without reinforcement (P < 0.05) for all laser powers tested. There was no difference between the test specimens and the controls with 0.5 mg/ml ICG solder for low laser powers, but at higher laser powers, the reinforced solder was stronger than the controls (P < 0.05). CONCLUSION: Reinforcement of liquid albumin solders in laser-assisted incision repair seems to have advantages in terms of acute breaking strength over conventional methods that do not reinforce the cohesive strength of the solder. 相似文献
23.
Isolation and characterization of propagable cell lines (HUNC) from the androgen-sensitive Dunning R3327H rat prostatic adenocarcinoma 总被引:1,自引:0,他引:1
Presnell SC; Borchert KM; Glover WJ; Gregory CW; Mohler JL; Smith GJ 《Carcinogenesis》1998,19(4):585-590
The Dunning H rat prostate tumor (R3327H) is a widely used experimental
model of human prostatic adenocarcinoma (CaP). The Dunning H tumor has been
characterized as androgen-sensitive, androgen-receptor (AR) positive,
prostate-specific antigen and prostatic acid phosphatase (PAP) positive. To
date, the tumor has been maintained by serial passage in vivo because of
the lack of an in vitro cell line that retains the characteristics of the
in vivo tumor. The objective of the present study was to establish a
propagable cell line from R3327H adenocarcinoma that maintained androgen
sensitivity and expression of AR, PSA and PAP. Tissue harvested from an in
vivo R3327H tumor was dissociated with collagenase and placed into
Richter's improved media (with supplements). A cytokeratin-positive
epithelial cell line (HUNC- E) and a vimentin-positive stromal cell line
(HUNC-S) were generated from the primary culture, subcultured continuously
for >300 days, and passaged >50 times. Survival of the HUNC-E cell
line in vitro depended on several media supplements, including
nicotinamide, insulin, transferrin, selenium and epidermal growth factor
(EGF). HUNC-E cells expressed AR and produced PSA and PAP throughout the
culture period, as confirmed by immunocytochemistry and Western blot
analyses. Addition of 14 nM testosterone (T) or dihydrotestosterone (DHT)
to HUNC-E cells, stimulated DNA synthesis as well as anchorage-independent
growth and PSA production, which demonstrated the androgen-sensitive nature
of the cells in vitro. When HUNC-E and HUNC-S cells were combined in a 3:1
ratio and introduced subcutaneously into syngeneic male hosts, tumors
formed in 2/3 animals with an average latency of 7 months. RT-PCR and
immunocytochemical characterization of the HUNC cell lines revealed that
the cells expressed several growth factors and their cognate receptors,
including HGF, TGF-alpha and the TGF-betas, indicating the establishment of
potential autocrine loops in the neoplastic cells. The HUNC-E and HUNC-S
CaP cell lines, which retain the characteristics of the epithelial and
stromal components of the in vivo R3327H tumor, will allow a more thorough
and informative molecular and biological analysis of prostatic
adenocarcinoma.
相似文献
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Between January 1995 and Jul 1997, 474 patients with anterior knee pain resistant to conservative treatment were referred
for MR of the knee. The MR examination consisted of routine sequences with an additional patellofemoral dynamic examination
using a technique that has been developed at this institution. The dynamic study examines both knees simultaneously, with
the patient supine and the quadriceps loaded. No gating or restraint apparatus is needed. Patellar subluxation or tilt was
present in 188(40 %) of cases, bilateral in 104 and unilateral in 84 cases (right 39, left 45). It was classified as mild
in 51 %, moderate in 39 % and severe in 10 %. Subluxation was more prevalent in females than males (42 % vs. 37 %) and this
was most obvious in the severe group where 68 % were female. In 90 knees selected at random, four measurements of patellofemoral
morphology were obtained using reconstructed images from a volume gradient echo sequence. These measurements were correlated
with the degree of subluxation or tilt. A tibial tubercle distance greater than 20 mm, a femoral sulcus angle greater than
150 degrees, sulcus depth less than 4 mm were specific for subluxation but no measurement proved to be sufficiently sensitive
to preclude a tracking study. MRI can be used to define more precisely the anatomy of the extensor mechanism and its relationship
to the femur and tibia, in both a static and dynamic setting. In this way, patients with anterior knee pain can be classified
more accurately and the outcomes of treatment more reliably assessed.
Received: 17 September 1999; Revised: 31 January 2000; Accepted: 4 February 2000 相似文献
26.
Nevi of the conjunctiva generally develop during the first 2 decades of life, and are almost entirely restricted to the epibulbar surface, the plica, the caruncle, and the lid margin. Therefore, any elevated pigmented lesion of the forniceal or tarsal conjunctiva acquired later in life must be regarded with suspicion as a melanoma or melanoma precursor, and a biopsy should be done routinely. This report is, to the best of the authors' knowledge, the first histopathologic documentation of nevi located in the palpebral conjunctiva. One nevus was acquired and the other was probably congenital. 相似文献
27.
A standardised ultrasonic diagnosis and an accurate prevalence for the retroverted uterus in general gynaecology patients 总被引:1,自引:0,他引:1
Haylen BT McNally G Ramsay P Birrell W Logan V 《The Australian & New Zealand journal of obstetrics & gynaecology》2007,47(4):326-328
Transvaginal ultrasound with an empty bladder is recommended as a standardised ultrasonic technique for the accurate diagnosis of the retroverted uterus. Using this method, the prevalence of the retroverted uterus in 480 general gynaecological patients attending for subspecialist gynaecological ultrasound was 18%. The anteverting effect of the full bladder required for transabdominal ultrasound reduces the prevalence of the retroverted uterus to 13% (P < 0.001). 相似文献
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29.