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1.
Gonadal steroid levels were determined in the ovary ofSalamandra salamandra infraimmaculataduring the reproductive cycle in populations from a xeric region in northern Israel. Varying proportions of previtellogenic and vitellogenic oocytes were present throughout the year, and mature oocytes were present in winter and spring. The numbers of mature oocytes were greater between December and April, after parturition. The levels of 17β-estradiol and testosterone rose during oocyte vitellogenesis and maturation. Levels of progesterone and 17α-hydroxy progesterone appeared to be related to the level of vitellogenesis. Gravid females contained greater quantities of all four steroids than did nongravid females.  相似文献   
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Acrylic and composite resin facings may fracture or become detached from the metal framework. Insufficient retention, abrasion and trauma are among the causes of these phenomena. Clinical and laboratory techniques have been developed to fabricate facings by means of light-curing composite systems such as the Dentacolor (Kulzer, Inc.) system. The effect of different polishing methods, obtained in both techniques using the same material, was studied with SEM on samples. Finishing and polishing procedures were accomplished using fine finishing diamonds, diamond burs and sof-lex discs. Smooth and lustrous surfaces were obtained with finishing discs, in contrast to techniques using other finishing instruments. Little or no difference in surface texture was observed between samples finished by clinical and those finished by laboratory techniques.  相似文献   
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Since 9/11, hospitals and health authorities have been preparing medical response in case of various mass terror attacks. The experience of Tel Aviv Sourasky Medical Center in treating suicide-bombing mass casualties served, in the time leading up to the war in Iraq, as a platform for launching a preparedness program for possible attacks with biological and chemical agents of mass destruction. Adapting Quarantelli's criteria on disaster mitigation to the "microinfrastructure" of the hospital, and including human behavior experts, we attempted to foster an interactive emergency management process that would deal with contingencies stemming from the potential hazards of chemical and biological (CB) weapons. The main objective of our work was to encourage an organization-wide communication network that could effectively address the contingent hazards unique to this unprecedented situation. A stratified assessment of needs, identification of unique dangers to first responders, and assignment of team-training sessions paved the way for program development. Empowerment through leadership and resilience training was introduced to emergency team leaders of all disciplines. Focal subject matters included proactive planning, problem-solving, informal horizontal and vertical communication, and coping through stress-management techniques. The outcome of this process was manifested in an "operation and people" orientation supporting a more effective and compatible emergency management. The aim of article is to describe this process and to point toward the need for a broad-spectrum view in such circumstances. Unlike military units, the civilian hospital staff at risk, expected to deal with CB casualties, requires adequate personal consideration to enable effective functioning. Issues remain to be addressed in the future. We believe that collaboration and sharing of knowledge, information, and expertise beyond the medical realm is imperative in assisting hospitals to expedite appropriate preparedness programs.  相似文献   
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OBJECTIVE: The aim of this study was to evaluate the consecutive transfer approach of early embryos and blastocyst(s). DESIGN: Case-control study. SETTING: Public assisted reproduction technology unit. PATIENT(S): The study population consisted of three groups. In Group 1, a double transfer was performed on 136 consecutive women, that is, a standard transfer of embryos on day 2 or 3, and a second transfer of a blastocyst(s). In Group 2, an early transfer of only two embryos and a second transfer of one blastocyst were performed on 29 women from group 1 who had more than three high-quality embryos available for early transfer. In Group 3, a single early transfer was performed on 139 consecutive women who received three high-quality embryos (controls). INTERVENTION(S): Early embryo transfer, extended culture of the spare embryos, and a second transfer of a blastocyst(s). MAIN OUTCOME MEASURE(S): Implantation and pregnancy rates. RESULTSs): No differences were detected among the three groups in either pregnancy or implantation rates (pregnancy: 36.8%, 41.4%, and 37.4%, respectively; implantation: 14.6%, 19.9%, and 19.8%, respectively). CONCLUSION(S): The double (consecutive) transfer of early embryos and blastocyst(s) does not offer any advantage over the traditional early transfer. This may be from the adverse effect of the second transfer on the implantation process.  相似文献   
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The products of the MUC1 gene are known to be highly expressed in human breast cancer cells. The best characterized MUC1 protein is a polymorphic, type 1 transmembrane molecule containing a large extracellular domain composed primarily of a variable number of 20 amino acid tandem repeats. We have recently identified a novel protein product of the MUC1 gene, the MUC1/Y protein, that is also a transmembrane protein but is devoid of the tandem repeat array and its immediate flanking sequences. To analyze its expression in tumor cells we generated monoclonal antibodies directed against the MUC1/Y extracellular domain (anti-MUC1/Yex MAbs). Epitope mapping identified the MAb, 6E6, which recognized the MUC1/Y isoform with exquisite specificity- the repeat-array-containing MUC1 isoform could not compete out this immunoreactivity. A 30mer peptide which is unique for MUC1/Y and corresponds to the "join" region generated by the MUC1/Y specific splice, abrogated all 6E6 MAb immunoreactivity towards MUC1/Y. Immunoprecipitation of the MUC1/Y protein with 6E6 MAbs revealed that, in contrast with the proteolytic cleavage of the tandem-repeat-array-containing MUC1 isoform, MUC1/Y is not cleaved. Flow cytometry analyses using the 6E6 MAbs demonstrated that the MUC1/Y isoform is expressed on the cell surface of both MCF-7 breast cancer cells and malignant epithelial cells present in effusions obtained from breast and ovarian cancer patients. Our results unequivocally establish that the MUC1/Y protein is expressed on the surface of breast cancer cells and cells of other epithelial malignancies. The anti-MUC1/Y MAbs described here can target MUC1/Y expressing tumor cells in vivo and are likely to be important reagents both for epithelial tumor diagnosis and immunotherapy.  相似文献   
8.
The aim of this study was to investigate whether equally high-quality embryos derived from standard in vitro fertilization (IVF) or from intracytoplasmic sperm injection (ICSI) differ in pregnancy potential. We evaluated all consecutive cycles from January 1996 to December 1997, in which only high-quality embryos were transferred. A total of 171 IVF and 148 ICSI cycle procedures, conducted in 153 and 130 women respectively, met with the inclusion criteria. A higher clinical pregnancy rate was recorded for the IVF group than the ICSI group (35% versus 29% respectively), although the difference did not achieve statistical significance. This result was detected despite the significantly higher mean age of the IVF patients compared with the ICSI patients (35 +/- 4.9 years and 33 +/- 5.2 years respectively). Controlling for the effect of patient age using linear regression analysis yielded a significantly higher clinical pregnancy rate for IVF therapy. In conclusion, IVF is associated with a significantly higher clinical pregnancy rate than ICSI even when high-quality, morphologically comparable embryos are utilized.  相似文献   
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We previously have shown that adenovirus type 5 E4orf4 protein associates with protein phosphatase 2A (PP2A) and induces apoptosis in transformed cells in a p53-independent manner. Here we show that the interaction between E4orf4 and PP2A is required for induction of apoptosis by the viral protein. This conclusion is supported by a mutation analysis of E4orf4 protein, showing a correlation between the ability to bind PP2A and to induce apoptosis, and by the observation that transfection of an antisense construct of the PP2A-B55 subunit reduces expression of the PP2A-B55 subunit and inhibits induction of apoptosis by E4orf4, but not by p53. The mutant analysis also indicates that even a low level of interaction with PP2A is sufficient to initiate the E4orf4 apoptotic pathway. In addition, E4orf4 inhibits cellular transformation by various oncogenes, and this function is coupled to its ability to induce apoptosis. Furthermore, expression of oncogenes in primary cell cultures sensitizes these cells to induction of apoptosis by E4orf4. Our results suggest that E4orf4 is a potentially useful tool for cancer gene therapy.  相似文献   
10.
Myocardial injury, developed after a period of ischemia/reperfusion (I/R) results in the destruction of functional heart tissue, this being replaced by scar tissue. Intracellular signaling pathways mediating cardiomyocyte death are partially understood and involve the activation of Ras. p38-MAPK, JNK and Mst-1 are downstream effectors of Ras protein. We hypothesized that S-farnesylthiosalicylic acid (FTS), a synthetic small molecule that detaches Ras from the inner cell membrane, consequently inhibiting Ras activity, reduces I/R myocardial injury in vitro and in vivo.Wistar rat hearts were isolated, mounted on the Langendorff apparatus and subjected to ischemia (30 min, 37 °C) and reperfusion. During the reperfusion period, the hearts were perfused with FTS (1 μM) solution or control buffer. Left anterior descending (LAD) ligation and subsequent reperfusion was performed in two groups of Wistar rats. Rats received 5 mg/kg FTS or PBS according to two protocols: (A) FTS or PBS were administered daily 7 days prior, immediately before and 14 days (every other day) after LAD occlusion or (B) every other day for 14 days post-I/R. Hearts from FTS-treated rats (Langendorff) and FTS-treated rats (protocol A) showed a significant improvement in myocardial performance and smaller scar tissue compared with the PBS group. Infarct size in the FTS-treated group was 12.7 ± 2% vs. 23.7 ± 4% in the PBS-treated (in vitro) group and 17.3 ± 2.5% vs. 36 ± 7% compared with control I/R rats (in vivo) p < 0.05. These effects may be associated with the down regulation of JNK as a short-term effector and with Mst-1 in the long-term remodeling process.  相似文献   
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