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991.
PURPOSE: To compare the antitumor activity and toxicity of the two induction chemotherapy treatments of paclitaxel, cisplatin, and fluorouracil (FU; PCF) versus standard cisplatin and FU (CF), both followed by chemoradiotherapy (CRT), in locally advanced head and neck cancer (HNC). PATIENTS AND METHODS: Eligibility criteria included biopsy-proven, previously untreated, stage III or IV locally advanced HNC. Patients received either CF (cisplatin 100 mg/m2 on day 1 plus FU 1000 [corrected] mg/m2 continuous infusion on days 1 through 5) or PCF (paclitaxel 175 mg/m2 on day 1, cisplatin 100 mg/m2 on day 2, and FU 500 mg/m2 continuous infusion on days 2 through 6); both regimens were administered for three cycles every 21 days. Patients with complete response (CR) or partial response of greater than 80% in primary tumor received additional CRT (cisplatin 100 mg/m2 on days 1, 22, and 43 plus 70 Gy). RESULTS: A total of 382 eligible patients were randomly assigned to CF (n = 193) or PCF (n = 189). The CR rate was 14% in the CF arm v 33% in the PCF arm (P < .001). Median time to treatment failure was 12 months in the CF arm compared with 20 months in the PCF arm (log-rank test, P = .006; Tarone-Ware, P = .003). PCF patients had a trend to longer overall survival (OS; 37 months in CF arm v 43 months in PCF arm; log-rank test, P = .06; Tarone-Ware, P = .03). This difference was more evident in patients with unresectable disease (OS: 26 months in CF arm v 36 months in PCF arm; log-rank test, P = .04; Tarone-Ware, P = .03). CF patients had a higher occurrence of grade 2 to 4 mucositis than PCF patients (53% v 16%, respectively; P < .001). CONCLUSION: Induction chemotherapy with PCF was better tolerated and resulted in a higher CR rate than CF. However, new trials that compare induction chemotherapy plus CRT versus CRT alone are needed to better define the role of neoadjuvant treatment.  相似文献   
992.
There is evidence that the duration of untreated psychosis may affect both the course and outcome of treatment in schizophrenic patients. In the present study, we used neuroendocrine probes to test the hypothesis that untreated psychosis may induce time-dependent changes in central serotonergic and dopaminergic neurotransmission. Prolactin responses to the administration of clomipramine (i.v.) and haloperidol (i.m.) were measured in healthy control subjects and in 16 never-treated male patients with DSM-IV diagnoses of schizophreniform or schizophrenic disorders of paranoid subtype, both before and after 5 weeks of treatment with haloperidol. In the drug-free state, schizophrenic patients exhibited significantly increased prolactin responses to clomipramine administration compared with both the healthy control subjects and the schizophreniform patients. Maximum prolactin responses to clomipramine in the total group of patients were positively correlated with the duration of psychotic illness and negatively correlated with changes in Positive and Negative Syndrome Scale (PANSS) total, negative symptoms and general psychopathology scores after 5 weeks of treatment with haloperidol. Prolactin responses to haloperidol challenge in the drug-free state were lower in the schizophreniform group than in the control and the schizophrenic groups, but the differences did not reach statistical significance. The results provide evidence that the persistence of psychotic psychopathology induces secondary neuroadaptive effects, which seem to involve changes in central serotonergic function.  相似文献   
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994.
995.
An inversion, inv(4)(p14q27), was found as the sole karyotypic anomaly at diagnosis in the bone marrow cells from a 65-year-old male patient with an M4 acute nonlymphocytic leukemia (ANLL). To our knowledge, the breakpoints observed in this case appear to be different from other inversions of chromosome 4 previously described in ANLL. The patient we described had a poor response to chemotherapy and had a short survival.  相似文献   
996.
Acute Care of the Elderly (ACE) units have been shown to improve outcomes for hospitalized elders. Because the literature offers little to describe the appropriate staffing of such units, we surveyed ACE units about their size, configuration, staffing, patient selection, training, and outcomes data. Although we had anticipated speaking with staff from 30 to 40 units, we were able to poll key personnel on only 18 ACE units. This article describes staffing and continuous quality improvement data for these sites.  相似文献   
997.
The efficacy of cryopreservation by direct plunging into liquid nitrogen (vitrification) of human pronuclear oocytes using open pulled straws with a super-finely pulled tip, as well as the ultrastructural changes caused by cooling and vitrification, were evaluated. Clinical and electron microscopic studies of cooled and vitrified oocytes were performed. Oocytes were cooled to 4 degrees C in the presence and absence of cryoprotectants, vitrified, warmed, cultured and transferred. Abnormally fertilized oocytes were examined by electron microscopy. Vitrified and warmed 2-pronuclear oocytes showed 71.1% survival rate and 83.3% developmental rate. One- and 3-pronuclear oocytes, after cooling without cryoprotectants (presumably non-viable), showed progressive swelling of mitochondrial smooth endoplasmic reticulum (SER). After vitrification, oocytes (presumably viable) showed the formation of large SER vesicles associated with mitochondria. The described protocol of vitrification of human pronuclear oocytes was shown to be effective in producing pregnancy. Normal ultrastructure after undergoing the described vitrification protocol was confirmed.  相似文献   
998.
OBJECTIVE: To evaluate the relative prognostic value of ultrasound findings during the first-trimester scan by univariate and logistic regression analysis in a group of asymptomatic women. STUDY DESIGN: A total of 125 asymptomatic pregnant women with a singleton conceptus, concordance between menstrual age and crown-rump length, and documented fetal activity, 25 for each gestational age between 6 and 10 weeks, were enrolled in the study and underwent a transvaginal sonographic examination. The following data were collected: yolk sac mean diameter and volume, gestational sac mean diameter and volume, fetal heart rate, maternal age, gestational age and presence of a retrochorial hematoma. The outcome variable was abortion, defined as pregnancy loss at any time up to 20 weeks' gestation. Normograms were constructed for volumes, mean diameters and fetal heart rate. Receiver-operator characteristic curves were performed in order to dichotomize maternal and gestational age. Univeriate analysis was performed by Fisher's exact test. Logistic regression was performed to test the relationship between independent variables and pregnancy outcome. RESULTS: In univariate analysis, the variables significantly associated with spontaneous abortion were maternal age > 34 years, yolk sac volume outside the 5th to 95th percentile, gestational sac volume < the 5th percentile and fetal heart rate outside the 5th to 95th percentile. In regression analysis only maternal age > 34 years, gestational sac mean diameter < 5th percentile and fetal heart rate outside the 5th to 95th percentile were significant in predicting abortion. CONCLUSION: Our data suggest that new three-dimensional parameters are of no clinical benefit in the prediction of abortion in nonbleeding, first-trimester pregnancy, when conventional sonographic parameters are used.  相似文献   
999.
1000.
A diagnostic test was applied at the National Autonomous University of Mexico School of Medicine using a two-part format with 42 clinical cases and 210 multiple-choice items. Residents were randomized into two groups: group A (printed test) and group B (computerized test). Academic performance was measured by determination of media, standard deviation, and correct-answer score; the exam was measured by reliability, difficulty index, and discrimination index and question/item assessment were calculated for item analysis. Residents answered a survey questionnaire and time taken to answer was controlled. Results showed that the printed test had higher achievement; there was better reliability for computerized format, and resident opinion was more favorable toward computer use. The two parts of the test were analyzed and results were produced for the first part of the test; in part two, results were very similar. We conclude that lack of experience in computer use could be a determining factor in our results.  相似文献   
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