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951.
Cloacal anomalies are extremely rare and have variable presentations. Prenatal diagnosis can be difficult especially if they present in late gestation. Here we present two cases diagnosed in the late third trimester and review the literature regarding prenatal diagnosis of cloacal anomalies.  相似文献   
952.
The 1969 Stonewall riot in New York City is widely celebrated as the beginning of the modern gay rights movement. However, the social changes that followed were possible only because of a decades-long indigenous organization. This article examines three traditional organizational theories on social action movements and applies Aldon Morris's analytical framework for understanding collective social action to the emergence of the modern U.S. gay civil rights movement. The author concludes that social workers need to understand how to gain access to and support indigenous social structures to assist oppressed groups to bring about social change.  相似文献   
953.
BACKGROUND: We performed a multi-institutional randomized trial comparing preoperative chemotherapy followed by surgery with surgery alone for patients with local and operable esophageal cancer. METHODS: Preoperative chemotherapy for patients randomly assigned to the chemotherapy group included three cycles of cisplatin and fluorouracil. Surgery was performed two to four weeks after the completion of the third cycle; patients also received two additional cycles of chemotherapy after the operation. Patients randomly assigned to the immediate-surgery group underwent the same surgical procedure. The main end point was overall survival. RESULTS: Of the 440 eligible patients with adequate data , 213 were assigned to receive preoperative chemotherapy and 227 to undergo immediate surgery. After a median possible study time of 55.4 months, there were no significant differences between the two groups in median survival: 14.9 months for the patients who received preoperative chemotherapy and 16.1 months for those who underwent immediate surgery (P=0.53). At one year, the survival rate was 59 percent for those who received chemotherapy and 60 percent for those who had surgery alone; at two years, survival was 35 percent and 37 percent, respectively. The toxic effects of chemotherapy were tolerable, and the addition of chemotherapy did not appear to increase the morbidity or mortality associated with surgery. There were no differences in survival between patients with squamous-cell carcinoma and those with adenocarcinoma. Weight loss was a significant predictor of poor outcome (P=0.03). With the addition of chemotherapy, there was no change in the rate of recurrence at locoregional or distant sites. CONCLUSIONS: Preoperative chemotherapy with a combination of cisplatin and fluorouracil did not improve overall survival among patients with epidermoid cancer or adenocarcinoma of the esophagus.  相似文献   
954.
Male C57BL/6N mice were chosen to determine Fos production during acquisition of context-dependent fear and after re-exposure to the conditioning context. Fear-conditioning was induced by a single exposure of mice to a context followed by an electric shock. Control groups consisted of mice exposed to context only (Context group) or to an immediate electric shock. When contextual retention was measured 24 h after conditioning (retention test 1), significant contextual generalization was observed. However, when animals were exposed to a different context from days 2-5 after conditioning and then tested for retention on day 6 (retention test 2), generalization was markedly reduced. After the training, the fear-conditioned mice produced higher Fos levels than mice exposed to an immediate shock in the hippocampus, medial amygdaloid nucleus and parietal somatosensory cortex. Both shock groups produced significantly more Fos than the Context group in the central nucleus of the amygdala. After retention test 1, fear-conditioned mice generated more Fos in the hippocampus and central amygdaloid nucleus than the two control groups. However, all groups exhibited similarly low Fos production after retention test 2. The results demonstrated that simultaneous Fos production in the hippocampus, central and medial nuclei of amygdala and somatosensory parietal cortex closely paralleled the ability of mice to acquire conditioned fear. In contrast, Fos production after the retention tests did not correlate with the expression of conditioned fear.  相似文献   
955.
Between 1/1986 and 6/1996, 37 consecutive patients affected by node-positive gastric cancer (GC) were treated with radical surgery and received 5-fluorouracil, epirubicin and mitomycin C (FEM) as adjuvant treatment. Only 57% of the patients received all six cycles and the reasons for treatment withdrawal were mainly related to concomitant pathologies and prolonged leukopenia. After a median follow-up of 39 months, the 3-year disease-free survival, disease-related survival and overall survival were 75.8%, 83.7% and 78.6% respectively. A statistically significant difference in survival was found in the subgroup of patients receiving more than three courses of treatment.  相似文献   
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Nucleocapsid protein (NCp7), which contains highly conserved retroviral zinc fingers, is essential in the early as well as the late phase of human immunodeficiency virus (HIV) life cycle and constitutes a novel target for AIDS therapy. HIV-1 NCp7 is a basic 55 amino acid protein containing two C(X)2C(X)4H(X)4C motif zinc fingers flanked by basic amino acids on each side. 2,2'-dithiobisbenzamides have previously been reported to release zinc from these NCp7 zinc fingers and also to inhibit HIV replication. Specifically, 2,2'-dithiobisbenzamides derived from simple amino acids showed good antiviral activities. The benzisothiazolone 3, the cyclic derivative of 2, was selected for clinical trials as an agent for AIDS therapy. Herein we report the syntheses and antiviral activities, including therapeutic indices, of 2,2'-dithiobisbenzamides derived from alpha-, beta- and gamma-amino acids. Electrospray ionization mass spectrometry was used to study the zinc-ejection activity of these compounds. Among the alpha-amino acid derived 2,2'-dithiobisbenzamides, analogues containing alkyl side chains were found to be antivirally active with good therapeutic indices. 2,2'-Dithiobisbenzamides, derived from beta- and gamma-amino acids, were found to possess better antiviral and therapeutic efficacies than the alpha-amino acid analogues. Thus compound 59 was found to possess an EC50 of 1.9 microM with a therapeutic index of > 50. Interestingly, 2,2'-dithiobisbenzamides derived from alpha-amino acids containing a protected acid function and polar side chains also exhibited very good antiviral activity.  相似文献   
958.
Following genomic damage, the cessation of DNA replication is co-ordinated with onset of DNA repair; this co-ordination is essential to avoid mutation and genomic instability. To investigate these phenomena, we have analysed proteins that interact with PCNA, which is required for both DNA replication and repair. One such protein is p21Cip1, which inhibits DNA replication through its interaction with PCNA, while allowing repair to continue. We have identified an interaction between PCNA and the structure specific nuclease, Fen1, which is involved in DNA replication. Deletion analysis suggests that p21Cip1 and Fen1 bind to the same region of PCNA. Within Fen1 and its homologues a small region (10 amino acids) is sufficient for PCNA binding, which contains an 8 amino acid conserved PCNA-binding motif. This motif shares critical residues with the PCNA-binding region of p21Cip1. A PCNA binding peptide from p21Cip1 competes with Fen1 peptides for binding to PCNA, disrupts the Fen1-PCNA complex in replicating cell extracts, and concomitantly inhibits DNA synthesis. Competition between homologous regions of Fen1 and p21Cip1 for binding to the same site on PCNA may provide a mechanism to co-ordinate the functions of PCNA in DNA replication and repair.  相似文献   
959.
960.
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