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81.
82.
H. J. C. M. Sterenborg M. Motamedi R. F. Wagner Jr M. Duvic S. Thomsen S. L. Jacques 《Lasers in medical science》1994,9(3):191-201
The feasibility of using in vivo autofluorescence for the diagnosis of skin cancer was evaluated. In vivo fluorescence measurements
were performed on healthy human volunteers, and patients with different types of benign and malignant skin tumours. Fluorescence
spectra as well as fluorescence images were acquired. The excitation-emission matrix of normal skin (n=3) showed a broad peak at the shortest excitation wavelength (365 nm) and at 440 nm fluorescence wavelength, smoothly decreasing
towards longer excitation and fluorescence wavelengths. Non-melanoma skin tumours (n=31) and control skin excited with 375 nm showed a broad fluorescence band from 400 to 700 nm, peaking around 436 nm. No significant
differences in measurements between tumours and the corresponding control sites were found. A large spatial variation in the
fluorescence intensity was observed both in the tumours and in the control sites. Standard deviations found ranged from 0.15
to 1.5 times the mean fluorescence. Fluorescence images, excited with 375 nm and taken with an image intensified CCD camera,
on eight malignant melanomas and eight benign pigmented lesions did not indicate any fluorescence intensity distribution specific
to the malignancy of the lesion. Neither the shape of the fluorescence spectra, nor the spatial distribution of the fluorescence
intensity showed any signature specific to the histopathological nature of the lesions investigated. Optical diagnostics of
skin tumours using the autofluorescence does not seem to be feasible at the present time. 相似文献
83.
Objective: Microvascular pericytes may contract in two different ways: In the first, a circumferential or radial mechanical force applied at right angles to the long axis of the vessel may constrict the underlying vessel affecting blood flow and transmural pressure. Retraction and elongation of pericyte processes may also occur tangentially and at right angles to the vessel axis and alter microvessel permeability by changing the amount of ablumenal surface covered or the openness of interendothelial junctions. In this study, cultured pericytes were utilized as a model experimental system to determine if vasoactive stimulation changes their shape in a manner consistent with this hypothesis. Methods: Pericytes cultured from isolated rate capillaries were subjected to angiotensin II and histamine. Their response was monitored by measuring the area of nonyielding substrate covered by the pericytes and the manner in which their shape changed. Shape changes were quantified by calculating the surface area: perimeter perimeter ratios. Results: Histamine significantly reduced surface area covered and the surface area: perimeter ratio. The pericyte processes retracted, resulting in elongated, spindle-shaped cells. These effects were nullified by the H1 blocker diphenhydramine suggesting a receptor-specific response. Angiotensin II also elicited contraction and reduced surface area, but the cells contracted laterally and longitudinally. The surface area: perimeter ratios also decreased. Conclusions: These results indicate that pericytes are capable of two types of contractile responses in culture, depending on the specific vasoactive stimulus. 相似文献
84.
Rest thallium-201 myocardial perfusion imaging in a patient with leukaemic infiltration of the heart
A. Cahid Civelek Jeffrey A. Brinker Edwaldo E. Camargo Jonathan M. Links Henry N. Wagner Jr. 《European journal of nuclear medicine and molecular imaging》1992,19(4):306-308
Despite the high incidence of leukaemic infiltration of the heart, only 8 cases of atrioventricular block due to leukaemia have been reported in the literature. Improvement in the heart block associated with disappearance of the leukaemic infiltrate has not been reported. A rest thallium-201 study was used in a 65-year-old man to demonstrate leukaemic infiltration of the heart which was associated with complete heart block. After chemotherapy, when the tumour burden was reduced and the leukaemia in remission, his heart block resolved, and a follow-up thallium scan was normal.
Offprint requests to: A.C. Civelek 相似文献
85.
Pelvic fractures are frequently complicated by concomitant vascular lacerations involving, particularly, branches originating from the internal iliac arteries. Massive hemorrhage may be difficult to be treated surgically. In such cases interventional radiology can be helpful and able to treat definitely extensive hemorrhage caused by pelvic trauma. 相似文献
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88.
Shock is defined as a disproportion between oxygen supply and consumption based on a deficient perfusion of vital organs. Reduction of circulating blood volume (hypovolemic shock), cardiac failure with low output (cardiac shock) or the failure of peripheral vascular resistance (distributive shock) can result in shock. Preclinically the diagnosis of shock is determined by exploration, physical examination and – some – monitoring only. Therapy is directed towards the underlying cause whilst recovery and maintenance of adequate perfusion of vitals and tissue are of primary importance. This strategy includes the application of oxygen, fluids and catecholamines. Moreover, the choice of the hospital for further therapy is crucial in case of emergency. 相似文献
89.
Nicole Rotter Hubert Wagner Sabine Fuchshuber Wolfgang J. Issing 《European archives of oto-rhino-laryngology》2003,260(5):254-257
Microcystic adnexal carcinoma is a rare cutaneous neoplasm characterized by slow but locally aggressive growth, which normally does not lead to systemic metastasis. Frequent local recurrences are reported, which are most likely due to insufficient operative technique. We present the fourth case of cervical ipsilateral metastatic microcystic adnexal carcinoma in an otherwise healthy woman. The patient presented with a previously diagnosed but not completely resected microcystic adnexal carcinoma in the area of the right posterior scalp and two palpable ipsilateral lymph nodes. The tumor was resected using intraoperative snap frozen histological evaluation of the resection borders. In the same procedure two lymph nodes were resected from the right neck. The lymph nodes were histologically assessed and showed infiltration by small strains of tumor cells. After exclusion of a second primary tumor, e.g., mammary carcinoma, as the cause for cervical lymph node metastases, we performed a modified radical neck dissection with resection of the sternocleidomastoid muscle and the accessory nerve, which was histologically proven to be perineurally infiltrated by tumor cells. In this second procedure the histological evaluation of the specimen showed no sign of remaining tumor infiltration. After exclusion of distant metastasis the patient was irradiated with 60 Gy. The patient is well 1 year after the initial treatment without signs of recurrence. 相似文献
90.
Dr. med. habil. Karl -Heinz Wagner 《Journal of molecular medicine (Berlin, Germany)》1941,20(22):574-576
Zusammenfassung Bei normal ernährten und Vitamin A-frei ernährten Ratten wird bei Sesamölzugabe keine Erhöhung der Thrombocyten beobachtet. Auch bei Gesunden und Kranken mit einer relativen Thrombopenie gelang es nicht, durch Verabreichung von Sesamöl die Thrombocyten zur Norm zu steigern. Die Anwesenheit des Faktors T im Sesamöl wird abgelehnt. 相似文献