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1.
Gene M. Heyman 《Psychopharmacology》1993,112(2-3):259-269
A series of experiments evaluated the determinants of preference for mixtures of ethanol plus sucrose relative to sucrose in rats. One dipper served 10% ethanol mixed with 10% sucrose, and the second dipper served 10% sucrose. Lever presses operated each dipper according to a variable-interval 5-s schedule. In three experiments the subjects were given pre-session meals of sucrose (2.5–20 ml) or sucrose (20 ml) plus chow (5 or 10 g). Pre-session meals decreased responding maintained by sucrose but not responding maintained by ethanol mixture. In two experiments body weight was varied from 85% to 125% of the initial free-feeding values. Increases in body weight, like pre-session meals, decreased responding reinforced by sucrose, but typically did not decrease responding reinforced by ethanol mixture. Throughout most of the study, ethanol consumption remained at about 1.25 ml per half hour session (3–4 g/kg per 30 min). For example, pre-session access to ethanol mixture decreased within-session ethanol consumption, but total consumption, counting both sources, remained about 1.25 ml/session. The within-session patterns of responding also differed. Responding reinforced by ethanol mix decreased as a function of ethanol consumption, whereas responding reinforced by sucrose was relatively constant throughout the session. The simplest explanation of the results is that ethanol's pharmacological consequences regulated preference. 相似文献
2.
Kazumasa Fujitani Jaffer A. Ajani Christopher H. Crane Barry W. Feig Peter W. Pisters Nora Janjan Garrett L. Walsh Stephen G. Swisher Ara A. Vaporciyan David Rice Angela Welch Jackie Baker Josephine Faust Paul F. Mansfield MD 《Annals of surgical oncology》2007,14(4):1305-1311
Background Significant tumor downstaging has been achieved in patients with localized gastric or gastroesophageal adenocarcinoma by induction
chemotherapy and preoperative chemoradiotherapy (CTX–CTXRT). However, the influence of CTX–CTXRT on operative morbidity and
mortality has not yet been clarified. The aim of the present study was to document the frequency and nature of morbidity and
mortality after surgery combined with CTX–CTXRT, and identify factors predictive of postoperative complications in patients
with localized gastric or gastroesophageal adenocarcinoma.
Methods A prospectively collected database on 71 consecutive patients who underwent CTX–CTXRT at M.D. Anderson Cancer Center between
January 1997 and August 2004 was reviewed. Postoperative morbidity and mortality were investigated, and risk factors for overall
complications were identified by multivariate logistic regression analysis.
Results Overall morbidity and mortality rates were 38.0% (27 patients) and 2.8% (2 patients), respectively. Age greater than 60 years
[relative risk 11.3 (95% confidence interval 2.50–50.6)] and body mass index (BMI) of 26 kg/m2 or above [relative risk 4.08 (95% confidence interval 1.08–15.4)] were significant risk factors for overall complications.
Conclusions CTX–CTXRT can be performed safely with an acceptable operative morbidity and a low operative mortality rate in patients with
gastric or gastroesophageal cancer, with careful consideration of added risk associated with age and obesity. 相似文献
3.
Robert M. Kelsey Sarah Reiff Stefan Wiens Tamera R. Schneider Elizabeth S. Mezzacappa William Guethlein 《Psychophysiology》1998,35(3):337-340
The interrater reliability and concurrent validity of two methods of scoring the ensemble-averaged impedance cardiogram were evaluated. Impedance cardiographic and electrocardiographic signals were recorded from 40 undergraduate men and women during a baseline rest period and a vocal mental arithmetic task period. Recordings were scored by four raters using a conventional method, involving ensemble averaging after careful editing of beat-to-beat waveforms, and a streamlined method, involving ensemble averaging without beat-to-beat editing. Intraclass correlations for interrater reliability exceeded .92, whereas intraclass correlations for concurrent validity exceeded .97, indicating excellent agreement between raters and scoring methods for all cardiac measures. The streamlined method was significantly faster than the conventional method. The results indicate that variations in beat-to-beat editing do not constitute a serious source of error in the ensemble-averaged impedance cardiogram and support the interrater reliability and concurrent validity of the two scoring methods. 相似文献
4.
Combined large cell neuroendocrine carcinoma 总被引:1,自引:0,他引:1
Toshiya Bessho Keiya Yokochi Teruhisa Sakurai 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2004,52(9):426-428
We report a case of combined large cell neuroendocrine carcinoma. A 78-year-old man with vertigo was referred to our hospital
where chest X-ray revealed a tumor shadow in the right lung. A transbronchial lung biopsy specimen verified a diagnosis of
non-small cell lung carcinoma (cT1N0M0). Right lower lobectomy with mediastinal lymph node dissection (#7,8,9) was performed.
A postoperative histological diagnosis was combined large cell neuroendocrine carcinoma of a component of squamous cell carcinoma
[pT4 (pm) N2M0]. The patient received concurrent chemoradiotherapy due to upper mediastinal lymph node metastasis 4 months
after surgery. The chemoradiotherapy well responded and the patient remains well 9 months after surgery. 相似文献
5.
Anuchai Niwetpathomwat 《Comparative clinical pathology》2006,15(4):215-219
Doxycycline has a well known broad spectrum activity against bacteria and rickettsia, as well as Ehrlichia spp. However, the use of doxycycline for the treatment of concurrent ehrlichiosis and babesiosis has rarely been evaluated, especially in veterinary hospital populations. A retrospective study of 70 canine ehrlichiosis and 12 canine babesiosis concurrent infections from Out Patient Department patients at Chulalongkorn Small Animal Teaching Hospital, admitted during 2001–2003, were studied. The results showed a complete curative effect of doxycycline on both canine ehrlichiosis and canine babesiosis concurrent infections. The red blood cell indices after treatment were significantly higher in canine ehrlichiosis (P < 0.05). The platelet cell counts after treatment were significantly higher in concurrent canine ehrlichiosis and babesiosis infections (P < 0.05). Doxycycline can be recommended as the drug of choice for both canine ehrlichiosis and canine babesiosis and concurrent infections of both conditions in veterinary hospitals. 相似文献
6.
Osman Serhat Guner Latif Volkan Tumay 《Asian journal of surgery / Asian Surgical Association》2021,44(6):841-847
BackgroundIn rectal cancer, extramural vascular invasion (EMVI) is the presence of tumour cells in blood vessels outside the muscular layer, which is associated with poor prognosis. Regression of EMVI on MRI following neoadjuvant chemoradiotherapy or its persistence may have prognostic implications.MethodsThis retrospective study included 52 patients with rectal cancer who underwent total mesorectal excision following long-course neoadjuvant chemoradiotherapy (CRT). EMVI assessments were done on previous pelvic MRIs obtained before neoadjuvant CRT and eight weeks after the completion of neoadjuvant chemoradiotherapy in initially EMVI positive cases.ResultsPersistently EMVI positive patients had worse overall survival and disease-free survival compared to initially EMVI negative patients and patients who returned to negative (p < 0.001 for both). Multivariate analysis identified persistent EMVI positivity after neoadjuvant treatment (HR, 102.9; p = 0.003) as significant independent predictor of worse overall survival; and persistent EMVI positivity (HR, 17.0; p = 0.002), mesorectal fascia involvement after neoadjuvant treatment (HR, 8.0; p = 0.017), and poor differentiation (HR, 10.3, p = 0.012) as significant independent predictors of worse disease-free survival.ConclusionPersistent EMVI positivity after neoadjuvant therapy appears to be an independent factor for poor overall survival; and persistent EMVI positivity as well as mesorectal fascia involvement on post neoadjuvant therapy MRI and poor differentiation appears to be important predictors of poor disease-free survival in rectal cancer patients. 相似文献
7.
侧方淋巴引流是低位直肠癌3个重要的淋巴引流方向之一。沿引流途径清扫淋巴结是直肠癌根治术基本要求,也决定淋巴结清扫范围。但侧方淋巴结是区域淋巴结还是远处淋巴结,一直存在争议。这带来新辅助放化疗和侧方淋巴结清扫、以及新辅助放化疗对侧方淋巴结转移疗效的争议。笔者综合分析国内外研究进展,对直肠癌侧方淋巴结转移规律、影响侧方淋巴结转移复发危险因素以及放化疗前后MRI检查对侧方淋巴结评估等进行深入阐述,并结合临床实践,探讨进展期低位直肠癌新辅助放化疗后侧方淋巴结清扫的选择和意义。 相似文献
8.
Rationale: Progressive ratio (PR) schedules have become well accepted for testing the reinforcing effectiveness of drugs. This study
extends the methods to concurrent PR schedules with different concentrations of orally delivered phencyclidine (PCP). Objective: The sensitivity of the procedure is tested by presenting different PCP concentrations with independently-operating PR schedules.
Method: PCP self-administration was investigated in seven rhesus monkeys. Six different PCP concentrations (0.03–1.0 mg/ml) and
water were randomly paired (21 pairings). Liquid delivery (24 ml) was contingent upon lip-contact responses on solenoid-operated
drinking spouts; whereby, the response requirement or fixed-ratio (FR) increased (from 8 to 16, 32, 64, 128... to 4096) after
each successful completion of a previous FR and subsequent liquid delivery. Monkeys self administered PCP during daily 3-h
sessions, and each pair of concentrations was held constant until behavior had stabilized for at least 4 days. Results: The higher of the two PCP concentrations always maintained greater responding, PR break point (BP), or the last ratio completed,
and liquid deliveries than did the lower concentration. However, the monkeys did not exclusively respond on the drinking spout
that yielded the higher drug concentration. When examined across all drug pairings, the percentage of total available deliveries
of the higher concentration was significantly greater than those of the lower concentration. The monkeys maximized the amount
(mg) consumed for the response output. Responding, BPs and liquid deliveries maintained by 0.12 and 0.25 mg/ml PCP were significantly
greater than other PCP concentrations; however, drug intake (mg) increased directly with PCP concentration. Conclusion: These results indicate that concurrent PR schedules using oral drug self-administration and a concurrent choice paradigm
reliably provide an estimation of relative reinforcing strength, and behavior maintained by these schedules is sensitive to
small changes in PCP concentration.
Received: 18 September 1998 / Final version: 28 December 1998 相似文献
9.
Mark T. Jennings Michael L. Freeman Michael J. Murray 《Journal of neuro-oncology》1996,28(2-3):207-222
This article will review the current treatment of pediatric patients with diffuse pontine gliomas (DPG) and discuss three potential avenues of therapeutic research including (i) radiotherapy (RT) in combination with radiation sensitizers, (ii) dose-intensive, induction chemotherapy with hematopoietic support followed in sequence with RT applied as a consolidation therapy, and (iii) the interleafed application of phase-specific chemotherapeutic agents and hyperfractionated external beam radiotherapy (HFEBRT) referred to as chemoradiotherapy. 相似文献
10.
Treatment of oesophageal cancer with preoperative chemoradiotherapy may increase operative mortality
J. Balart J. Balmaa X. Rius R. Salazar M. Gallen S. Navarro A. Arcusa E. Gallardo J. Brunet 《European journal of surgical oncology》2003,29(10):884-889
AIMS: This phase II multicentric study evaluates a modified preoperative chemoradiotherapy schedule. METHODS: Patients <75 years with potentially resectable neoplasm were eligible. Treatment included an initial course of CDDP 100 mg/m2 (Day 1) and 5-FU CI 5000 mg/m2 (Days 1-5) followed by 45 Gy (Days 28-63) and 5-FU CI 5000 mg/m2 (Days 28-33), CDDP 75 mg/m2 (Day 56) and 5-FU CI 3750 mg/m2 (Days 56-61). Regional lymph nodes were irradiated. RESULTS: Nineteen patients were studied. Oesophagectomy was performed in 17. Clear margins were achieved in 16 of these. Eight patients showed a pathologic complete response (pCR). One patient died of infection during the preoperative treatment and four died due to acute surgical complications. The study was closed prematurely because of excessive mortality. Median follow-up was 19 months. Local and regional relapse occurred in one and three patients, respectively. Median time and actuarial 3-year of overall survival and progression free rates were 18.6 months and 28%, and 12.7 months and 10.4%, respectively. CONCLUSIONS: This schedule showed a high pCR, resectability and local control rate. Treatment-related mortality limits its clinical applicability, but further investigations are warranted. 相似文献