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961.
962.
Farina B Bartoli C Bono A Colombo A Lualdi M Tragni G Marchesini R 《Physics in medicine and biology》2000,45(5):1243-1254
In an attempt to overcome the subjectiveness of clinical observation in the diagnosis of cutaneous melanoma, a computerized method is proposed. Reflectance images of 237 pigmented lesions (67 melanomas and 170 non-melanomas) were analysed using a telespectrophotometric technique. This device consists of a CCD camera with 17 interference filters. Images were acquired at selected wavelengths, from 420 to 1040 nm. Morphological and reflectance related parameters were extracted from the wavelength-dependent images of the lesions. The most significant features in the comparison between benign and malignant lesions were: lesion dimension (P < 10(-8) at 578 nm); mean value (P < 10(-7) at 940 nm) and standard deviation (P < 10(-4) at 904 nm) of lesion reflectance; lesion roundness (P < 10(-5) at 461 nm); and border irregularity (P < 10(-4) at 461 nm). Based on these parameters, a discriminant function between the two populations of lesions (naevi and melanomas) was obtained. By using the results of the analysis of the recruited lesions as 'training data', discriminant functions enabled the assignment of a score, or a 'risk probability', to each studied lesion. By imposing a sensitivity of 80% (a figure that mimics the diagnostic capability of an experienced clinician), entering or not entering the lesion dimension as input data in the discriminant analysis led to a specificity of 51% or 46% respectively. The high number of false-positive cases, which is a consequence of the selection criteria of the lesions, is, at present, the major limitation of the current technique. Nevertheless, our results suggest that an imaging-based computer-assisted device could be capable of discriminating malignant lesions mainly by evaluation of reflectance, especially in the infrared region, and shape properties. The dimension of a lesion should not be essential in the diagnosis of melanoma and, in our opinion, small melanomas should be recognized by a computer system as well as they are on clinical grounds. 相似文献
963.
A Branchereau P E Magnan H Espinoza J M Bartoli 《The Journal of cardiovascular surgery》1991,32(5):604-612
Ninety seven patients (mean age: 58 years) with lesions involving the subclavian artery were studied to determine the relationship between clinical symptoms, angiographic lesions and Doppler-detected hemodynamic disorders. Ninety patients had vertebro-basilar insufficiency (VBI) and 7 had hemispheric manifestations or upper limb ischemia. Of the 105 lesions of the subclavian artery, we observed 76 stenoses greater than 50% and 29 complete occlusions. Thirty seven patients presented a unilateral subclavian lesion and 63 multiple lesions. Doppler examination of the vertebral artery including an upper limb hyperaemic test allowed classification of the patients into three stages: stage 1 "pre-subclavian steal" (35 patients): sudden decrease in the systolic vertebral flow with complete interruption during hyperaemia; stage 2 "intermittent subclavian steal" (18 patients): transient inversion of vertebral during systole with permanent inversion for 1 or 2 minutes after hyperaemia; stage 3 "permanent subclavian steal" (33 patients): complete inversion of the vertebral flow without diastolic flow and increase of flow during hyperaemia. The clinical, hemodynamic and angiographic findings were compared. In stage 1, 65.7% of the patients presented severe VBI (at least two signs) and 66% had a 50 to 70% stenosis of the subclavian artery. In stage 2, 66.6% of the patients presented severe VBI and 78% had a 75 to 95% stenosis. In stage 3, 72.7% of the patients had severe VBI and 73% had either subtotal or complete occlusion of the subclavian artery. There was no correlation between the severity of VBI and the hemodynamic stages but a strong correlation between the hemodynamic grades and the anatomical lesions.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
964.
Vermeiden JP; Roseboom TJ; Goverde AJ; Suchartwatnachai C; Schoute E; Braat DD; Schats R 《Human reproduction (Oxford, England)》1997,12(7):1399-1402
In the spontaneous menstrual cycle, the mid-cycle gonadotrophin surge
causes maturation of the cumulus-oocyte complex, mucification of cumulus
cells and expansion of the cumulus oophorus, resumption of meiosis and
maturation of the cytoplasm of the oocyte. Whether this is an effect purely
of luteinizing hormone (LH) or whether follicle stimulating hormone (FSH)
also plays a role is unknown. The effect of an artificially induced FSH
surge at the time of human chorionic gonadotrophin (HCG) injection on
maturation of the cumulus-oocyte complex was investigated in a prospective
randomized double-blind trial. Twelve patients underwent controlled ovarian
hyperstimulation [long gonadotrophin-releasing hormone agonist
(GnRHa)/human menopausal gonadotrophin (HMG) protocol] for in-vitro
fertilization (IVF) treatment. At the time of HCG administration, six
patients received a bolus injection of FSH (450 IU i.m.); the other six
patients received a placebo. The peak plasma concentrations of FSH of the
experimental group were compared with the peak values of FSH obtained at
the mid- cycle gonadotrophin surge of the natural cycle of a group of 12
volunteers to validate the bolus injection of FSH. Maturation of the
cumulus-oocyte complex was quantified by measuring the expansion of the
cumulus, by the fertilization rate and the implantation rate. The quality
of the embryos was scored according the average morphology score. The bolus
injection of FSH mimicked the mid-cycle gonadotrophin surge. The mean peak
value of FSH (12.9 IU/l) in the experimental group was fully comparable
with the mean peak value of FSH (10.0 IU/l) of the mid-cycle gonadotrophin
surge in the natural cycle. No effect of a bolus injection of FSH on the
maturation of the cumulus-oocyte complex or any other outcome variable was
found. It is not advantageous to combine the final HCG injection with a
bolus injection of FSH in GnRHa/HMG stimulated cycles.
相似文献
965.
Angelo Di Leo Leonardo Ferrari Emilio Bajetta Cesare Bartoli Giovanni Vicario Daniele Moglia Rosalba Miceli Marina Callegari Aldo Bono 《Breast cancer research and treatment》1995,33(3):237-244
Summary Recently, compounds having pure antiestrogenic activity have become available. In this study, we examined the activity of the new steroidal antiestrogen EM-170 (N-n-butyl, N-methyl-11-(16-chloro-3,17-dihydroxy-estra-1,3,5-(10)-trien-7-yl) undecanamide) on the growth of 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary carcinoma stimulated by treatment with estrone (E1), a steroid known to play an important role as precursor of 17-estradiol (E2), especially in postmenopausal women. Twenty-five days after ovariectomy (OVX), tumor volume in control OVX animals decreased to 51.4 ± 11% of the initial volume; treatment with E1, administered by Silastic implants, stimulated tumor growth to 179 ± 21%. Treatment with the antiestrogen EM-170 at a dose of 200 µg (twice daily) not only completely reversed the stimulatory effect of E1, but also inhibited tumor growth to 30.5 ± 9.6%, an effect that is 41% (P < 0.01 vs OVX control) greater than that of ovariectomy alone. At a relatively low dose of 40 µg (twice daily), 20 days of treatment with EM-170 reversed by 55% the stimulatory effect of E1 (1.0 µg, subcutaneously, twice daily) on tumor growth in OVX animals. On the other hand, the antiestrogen also induced a significant inhibitory effect on 17-hydroxysteroid dehydrogenase (17-HSD) activity in the DMBA-induced mammary tumors, an effect that is in agreement with the marked reduction caused by the same treatment on tumor estradiol (E2) levels in E1-treated OVX animals. The present data show that the new steroidal antiestrogen EM-170 exerts a potent inhibitory effectin vivo on E1-stimulated growth of DMBA-induced mammary tumors, an effect that is probably mediated by both its antiestrogenic activity at the receptor level and its inhibitory effect on 17-HSD, thus inhibiting local E2 formation and facilitating the action of the antiestrogen at the receptor level. 相似文献
966.
Bartoli D Battista G Bertoncini S De Santis M Giusti S Orsi D Pirastu R Zingoni A Valiani M 《La Medicina del lavoro》1998,89(5):424-436
The investigation aimed at studying cause-specific mortality of art glass workers employed in 17 industrial facilities in Tuscany, Italy. A cohort of 3390 workers employed for at least 1 year was obtained from company payrolls. Follow-up was between the year each factory started operations, mostly in the mid-fifties, and the end of 1993. The cause specific expected mortality was computed relative to Tuscany rates, specified for gender, 5-year age groups and calendar year. Separate analyses were carried out for the job titles of makers, batch mixers and grinders. For males, 3180 individuals, the observed mortality for cancer causes was above the expected for the lung [standardized mortality ratio (SMR) 123, 10 observed (Obs)], larynx (SMR 166, 10 Obs), stomach (SMR 105, 30 Obs) and brain (SMR 150, 7 Obs). For non-cancer causes observed mortality was above expected for hypertensive diseases (SMR 178, 10 Obs) and diseases of the genitourinary system (SMR 169, 11 Obs). Increases for the above listed causes were shown also among makers. Mortality for larynx and lung cancer increased with time since first exposure and significantly increased SMRs were observed for 21 or more years since first exposure: this pattern was still present with smoking adjustment. The results showed consistently increased mortality for lung and larynx cancer in the overall cohort and among makers. Stomach cancer, brain cancer, hypertensive diseases and diseases of the genitourinary system were also increased in the overall cohort and among makers. 相似文献
967.
Microdeletions of the Y chromosome and intracytoplasmic sperm injection: from gene to clinic 总被引:7,自引:11,他引:7
Kremer JA; Tuerlings JH; Meuleman EJ; Schoute F; Mariman E; Smeets DF; Hoefsloot LH; Braat DD; Merkus HM 《Human reproduction (Oxford, England)》1997,12(4):687-691
Intracytoplasmic sperm injection (ICSI) is a successful treatment option
for severe male infertility, although the aetiology of the disorder remains
unclear in most cases. Recently, microdeletions in the AZF region of the Y
chromosome have been detected in men with azoospermia or severe
oligozoospermia. In this study we investigated the prevalence of
microdeletions in the AZF region of the Y chromosome in a population of men
undergoing ICSI, and looked for clinical characteristics of men with and
without this deletion. Blood was drawn from 164 men, who were on the
waiting list for ICSI treatment: 19 were azoospermic, 111 oligozoospermic
and 34 normozoospermic (after previous total fertilization failure). A
total of 100 men with proven fertility served as a control. Microdeletions
in the AZFc region were present in seven of the 111 oligozoospermic men
(6.3%). Compared with oligozoospermic men without microdeletions, men with
microdeletions had a lower concentration of follicle stimulating hormone
(FSH), a lower number of motile spermatozoa and a lower frequency of
abnormal findings at andrological history or examination. No microdeletions
were found in the azoospermic, normozoospermic and control groups. In
conclusion, microdeletions in the AZFc region are relatively frequently
found in men with severe unexplained oligozoospermia. In the ICSI era this
finding has an important impact because this form of male infertility is
now potentially hereditary. Therefore we recommend DNA screening (and
genetic counselling) before ICSI, especially in men with normal FSH, severe
oligozoospermia and no abnormal clinical andrological findings.
相似文献
968.
G. Antonutto M. Bartoli M. Melato 《Virchows Archiv : an international journal of pathology》1975,368(1):23-34
Summary This study was carried out in order to define the histochemical behaviour of the substance present in follicles of normal parathyroid glands obtained at routine autopsies. It was noticed that these follicles with typical amyloid staining properties are constantly present in old persons; furthermore the amyloid in question presents histochemical characteristics which identify it as Apudamyloid.With this in mind we studied the possible, concomitant, systemic, amyloid microdeposits; we noticed that intrafollicular Apudamyloid of the parathyroid gland is often encountered together with immune deposits which are sometimes present in the same gland though not necessarily in the follicles.We are grateful to Mr. L. Bortoletto for his technical assistance. 相似文献
969.
P Bartoli 《Annales de parasitologie humaine et comparée》1983,58(3):227-242
Cercariae and metacercariae of Meiogymnophallus strigatus (M. V. Lebour, 1908) have been found in some places along the coast of Camargue (South of France). Sporocysts and cercariae are parasites of Tellina tenuis. Metacercariae occur in various Bivalves, mainly in Donax trunculus and D. semistriatus. Cercariae and metacercariae are described. Relationship between cercariae and metacercariae is demonstrated. Metacercarial microhabitat is delimited. Reaction of D. trunculus in front of the metacercarial infection is studied. Some metacercariae are free-living in the extrapallial space, between the mantle and the shell. These larvae have an advanced genital maturity. Most of the metacercariae are massed together and are enclosed by the host's epithelium. Their excretory vesicle, which is packed with blackish granules, almost fills the entire body. Attempts to infect laboratory reared birds by feeding metacercariae from Donax trunculus were not successful. The natural final host is unknown. In consideration of the metacercarial anatomy, Cercaria strigata M. V. Lebour, 1908 is placed in the genus Meiogymnophallus H. L. Ching, 1965. 相似文献
970.
Carrara M Tomatis S Bono A Bartoli C Moglia D Lualdi M Colombo A Santinami M Marchesini R 《Physics in medicine and biology》2005,50(22):N345-N357
The aim of this study was to develop an algorithm for the automatic segmentation of multispectral images of pigmented skin lesions. The study involved 1700 patients with 1856 cutaneous pigmented lesions, which were analysed in vivo by a novel spectrophotometric system, before excision. The system is able to acquire a set of 15 different multispectral images at equally spaced wavelengths between 483 and 951 nm. An original segmentation algorithm was developed and applied to the whole set of lesions and was able to automatically contour them all. The obtained lesion boundaries were shown to two expert clinicians, who, independently, rejected 54 of them. The 97.1% contour accuracy indicates that the developed algorithm could be a helpful and effective instrument for the automatic segmentation of skin pigmented lesions. 相似文献