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21.
Schachter J Laish A Mekhmandarov S Feinmesser M Fenig E Tamir G Gutman H 《World journal of surgery》2000,24(4):491-495
Identification and histologic study of the sentinel node (SN) is an acceptable, yet not firmly established, guide for treating
intermediate-thickness melanoma. This study widens the range of applications of this technique. We included 97 patients with
intermediate-thickness melanoma lesions or lesions for which there is no standard treatment. Fifty-six underwent preoperative
lymphoscintigraphy, and all underwent intraoperative lymphatic mapping (IOLM) using blue dye, followed by frozen section study
and total node processing by serial sections. Elective lymph node dissection was performed in cases of metastasis to the sentinel
node or technical failures with high risk. Four categories were defined: (A) intermediate-thickness lesions (mean 2.27 mm)
(n= 45); (B) thin lesions (mean 1.14 mm) with risk factors of regional failure (n= 27); (C) lesion thickness close to but more than 4 mm (n= 10); and (D) lesions of undetermined thickness (n= 15). Median follow-up was 30 months (range 13–51 months). Intraoperative lymphatic mapping successfully identified the sentinel
node (SN) in 93% of basins explored. Metastases were detected in 11 SNs. There were three lymph basin recurrences in patients
with previously negative SNs, all salvaged by therapeutic lymph basin dissection and are NED (no evidence of disease). Two
SN+ patients had systemic recurrences; one died of his disease, and the other is alive with disease. One SN− patient died NED owing to other cause. This technique spared 83% of category A patients from lymph node dissection. It allowed
better staging and better decision making for treatment in categories B and D; and it prevented early regional recurrences
in category C patients. Intraoperative lymphatic mapping with SN guidance is a novel, low-morbidity approach applicable and
advantageous for a wide range and subgroups of melanoma patients. 相似文献
22.
Treatment variables in relation to oocyte maturation: Lessons from a clinical micromanipulation-assisted in vitro fertilization program 总被引:1,自引:0,他引:1
Ori M. Avrech Gil A. Goldman Onit Rufas Anat Stein Shoshana Amit Israel Yoles Haim Pinkas Benjamin Fisch 《Journal of assisted reproduction and genetics》1997,14(6):337-342
Objective: In an effort to understand the mechanism underlying the improved pregnancy rate observed in IVF cycles when gonadotropin-releasing
hormone analogues (GnRH-a) are applied, we investigated a possible relationship between treatment variables and oocyte-nuclear
maturity.
Design: Nuclear maturity was retrospectively assessed in cumulus-free, denuded oocytes, obtained from women undergoing micromanipulation-assisted
IVF treatment following controlled ovarian hyperstimulation with GnRH-a and menotropins.
Setting: The setting was the infertility and IVF unit of a tertiary academic medical center.
Participants: Two hundred twenty-one patients underwent 435 treatment cycles.
Main Outcome Measure: This was the proportion of germinal vesicle-intact immature (GVII) oocytes.
Results: One hundred fifty-four of the 3520 oocytes studied (4.4%) were in the GVII stage. These oocytes were found in 66 of the treatment
cycles (15.2%) and in 54 of the patients (24.4%). Cycles in which GVII oocytes were detected did not differ from those in
which all the aspirated oocytes were mature in the following respects: patient age, type and duration of infertility, controlled
ovarian hyperstimulation protocol and time of ovum pickup. However, the GVII group was characterized by a significantly higher
peak estradiol level, as well as a higher number of mature follicles visualized sonographically (diameter, >14 mm) and oocytes
retrieved.
Conclusions: Comparing the present findings with previously published data, it appears that the inclusion of GnRH-a in the stimulation
regimen is associated with a lower proportion of immature oocytes. A higher occurrence of oocyte-nuclear immaturity is apparently
associated with a significantly better ovarian response to stimulation. The high incidence of immature oocytes observed in
patients with normospermic partners and low fertilization rates in previous cycles may suggest that the fertilization failure
in some of these cases is due to oocyte, rather than sperm, dysfunction. 相似文献
23.
Ron Epelbaum Channa Shalitin Ruth Segal Clari Valansi Ida Arselan David Faraggi Michelle Leviov Menahem Ben-Shahar Nissim Haim 《Pathology oncology research : POR》1998,4(4):271-276
A novel serum 21 kDa haptoglobin-related protein (Hpr) was investigated in patients with malignant lymphoma, to evaluate its
correlation with clinical and histologic features at presentation and its possible role as a tumor marker for patient outcome.
One hundred fifty eight serum samples were taken from 88 patients with non-Hodgkin’s lymphoma (n=58) and Hodgkin’s disease
(n=30) at presentation and in the course of follow-up. Sera from 61 healthy volunteers served as normal controls. Serum Hpr
levels in the lymphoma patients (median 430xl03 u/ml, range 0-4000xl03) were significantly higher than in the control group (median 68xl03 u/ml, range 0-180xl03) (p=0.0001). Higher median Hpr values were detected in patients with advanced disease (p=0.013), “B” symptoms (p=0.029) and
in males (p=0.053). There was also a significant correlation between Hpr and erythrocyte sedimentation rate (p=0.028). Serial
determinations showed a significant decrease of the initial Hpr values obtained after treatment in 41 patients, 38 of whom
achieved complete remission. In the follow-up period additional Hpr measurements were taken from 17 patients. Three of them
eventually relapsed, and showed increased Hpr levels at the time of relapse. Hpr levels remained low in 11 of 14 patients
who maintained complete remission, and increased in three. In conclusion, serum Hpr is a new serum tumor marker of potential
use in the clinical setting of lymphoma.
This work is dedicated to the memory of Dr. Arie H. Bartal, a dedicated oncologist and friend. This work was supported by
Chemotech Thechnologies Ltd., by grant no. 3676 from the Chief Scientist’s Office of the Ministry of Health, Israel, and by
the Fund for Promotion of Research in the Technion. 相似文献
24.
Einat Shemesh-Mayer Dana Gelbart Eduard Belausov Nisan Sher Ahuva Daus Haim D. Rabinowitch Rina Kamenetsky-Goldstein 《Viruses》2022,14(10)
Garlic lost its ability to produce true seeds millennia ago, and today non-fertile commercial cultivars are propagated only vegetatively. Garlic viruses are commonly carried over from one generation of vegetative propagules to the other, while nematodes and arthropods further transmit the pathogens from infected to healthy plants. A recent breakthrough in the production of true (botanical) garlic seeds resulted in rapid scientific progress, but the question of whether viruses are transmitted via seeds remains open and is important for the further development of commercial seed production. We combined morpho-physiological analysis, fluorescence in situ hybridization (FISH), and PCR analysis to follow potyvirus localization and translocation within garlic fertile plants and seeds. Spatial distribution was recorded in both vegetative and reproductive organs. We conclude that garlic potyviruses are translocated to the seeds from the infected mother plant during flower development and post-fertilization, while pollen remains virus-free and does not contribute to seed infection. Therefore, the main practical goal for virus-clean seed production in garlic is the careful maintenance of virus-free mother plants. Although garlic pollen is free of potyviral infection, the male parents’ plants also need to be protected from contamination, since viral infection weakens plants, reducing flowering ability and pollen production. 相似文献
25.
Nir Paran Yfat Yahalom-Ronen Ohad Shifman Shirley Lazar Ronen Ben-Ami Michal Yakubovsky Itzchak Levy Anat Wieder-Feinsod Sharon Amit Michal Katzir Noga Carmi-Oren Ariela Levcovich Mirit Hershman-Sarafov Alona Paz Rebecca Thomas Hadas Tamir Lilach Cherry-Mimran Noam Erez Sharon Melamed Moria Barlev-Gross Shay Karmi Boaz Politi Hagit Achdout Shay Weiss Haim Levy Ofir Schuster Adi Beth-Din Tomer Israely 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2022,27(35)
The current monkeypox virus global spread and lack of data regarding clinical specimens’ infectivity call for examining virus infectivity, and whether this correlates with results from PCR, the available diagnostic tool. We show strong correlation between viral DNA amount in clinical specimens and virus infectivity toward BSC-1 cell line. Moreover, we define a PCR threshold value (Cq ≥ 35, ≤ 4,300 DNA copies/mL), corresponding to negative viral cultures, which may assist risk-assessment and decision-making regarding protective-measures and guidelines for patients with monkeypox. 相似文献
26.
We have studied the metabolism of VP-16-213 (etoposide, VP-16), an antitumor agent, by mouse liver microsomes to reactive intermediates and the subsequent covalent binding to microsomal proteins. This metabolism was shown to involve the O-demethylation of VP-16 and resulted in the formation of a 3',4'-dihydroxy derivative (DHVP-16) which was identified by both HPLC and mass spectrometry. The formation of DHVP-16 was cytochrome P-450-mediated as indicated by its dependence on NADPH, its increased production following treatment of mice with phenobarbital, and its marked inhibition by SKF-525A and piperonyl butoxide. Furthermore, DHVP-16 formation required oxygen. Microsomal incubation of VP-16 resulted in an irreversible binding of the drug to the proteins, which was also shown to be cytochrome P-450 dependent. The covalent binding of the VP-16 metabolite(s) was inhibited by DHVP-16 in a dose-dependent fashion, suggesting that the reactive intermediates that bound to proteins were derived from DHVP-16. Electron spin resonance studies indicated that the same semiquinone radical was formed during enzymatic (oxidation or reduction) metabolism of DHVP-16 and the o-quinone derivative of VP-16 (VP-16-Q). VP-16-Q and its semiquinone radical are suggested to be the bioalkylating species. 相似文献
27.
28.
29.
Karl M Potier M Schulman IH Rivera A Werner H Fornoni A Elliot SJ 《Endocrinology》2005,146(2):889-900
30.
Ike D. Tanabe M.D. Anthony DiTomaso M.D. Haim Pinkas M.D. Dobromir Pencev M.D. 《The American journal of gastroenterology》1995,90(3):504-505
We describe an unusual case of a 32-yr-old man who presented with massive GI hemorrhage as an initial manifestation of an ileal duplication cyst. The lesion was first revealed by visceral angiography during investigation of the bleeding source. At laparotomy, a large ileal duplication containing full-thickness gastric-type mucosa was identified. Ulceration of the ileal mucosa adjacent to the communicating orifice was found to be the source of bleeding. Duplications of the alimentary tract are rare congenital malformations. Patients usually present in infancy and childhood, although delayed complications can present in adulthood. This entity should be considered among other lesions that can cause massive GI hemorrhage not diagnosable by endoscopy. 相似文献