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11.
Noradrenergic projections from the dorsomedial medulla reach the shell of the nucleus accumbens (NAcc), a structure implicated in both reward and feeding behavior. Despite this relationship, the effect of food reward on accumbens norepinephrine (NE) remains uninvestigated. In the course of assessing dopamine (DA) in the NAcc during sucrose ingestion [0.03, 0.1, and 0.3 M; Am. J. Physiol., Regul. Integr. Comp. Physiol., 286 (2004) R31], we also analyzed NE in the microdialysis samples from 14 ad-libitum-fed male rats. In contrast to DA, which increased with sucrose concentration (+20-47%) during sham feeding, in the same animals, NE levels were reduced (approximately -20%), regardless of sucrose concentration. These results demonstrate a novel relationship between accumbens DA and NE during orosensory stimulation with a preferred nutrient.  相似文献   
12.
The hunt for genes influencing behavior may be aided by the study of intermediate phenotypes for several reasons. First, intermediate phenotypes may be influenced by only a few genes, which facilitates their detection. Second, many intermediate phenotypes can be measured on a continuous quantitative scale and thus can be assessed in affected and unaffected individuals. Continuous measures increase the statistical power to detect genetic effects (Neale et al., 1994), and allow studies to be designed to collect data from informative subjects such as extreme concordant or discordant pairs. Intermediate phenotypes for discrete traits, such as psychiatric disorders, can be neurotransmitter levels, brain function, or structure. In this paper we conduct a multivariate analysis of data from 111 twin pairs and 34 additional siblings on cerebellar volume, intracranial space, and body height. The analysis is carried out on the raw data and specifies a model for the mean and the covariance structure. Results suggest that cerebellar volume and intracranial space vary with age and sex. Brain volumes tend to decrease slightly with age, and males generally have a larger brain volume than females. The remaining phenotypic variance of cerebellar volume is largely genetic (88%). These genetic factors partly overlap with the genetic factors that explain variance in intracranial space and body height. The applied method is presented as a general approach for the analysis of intermediate phenotypes in which the effects of correlated variables on the observed scores are modeled through multivariate analysis.  相似文献   
13.
BackgroundSurgical staging in endometrial cancer includes a systematic lymphadenectomy with significant morbidity, although its therapeutic role is unclear. Sentinel lymph node (SLN) study is a less morbid alternative to identify nodes most likely to be metastatic, permitting selective removal and thus reducing morbidity without compromising oncological safety. This study was done using blue dye single labelling to study the feasibility and utility in identifying SLN in early disease.MethodsTwenty-two patients of early-stage low-risk disease during surgical staging underwent cervical injection of methylene blue, SLN mapping, and sampling as per the standard algorithm, followed by a systematic lymphadenectomy in all cases. SLN were submitted separately for ultrastaging (US).ResultsTwenty patients underwent the procedure, and SLN could be identified in 18 patients with an overall mapping rate of 90% with a bilateral mapping rate of 70%, and a negative mapping rate of 10%. 57 SLN were identified along with two suspicious non-sentinel nodes and 11 were metastatic on US with a sensitivity of 66.7% and NPV of 87.5%. All patients with metastatic nodes, however, could be identified by applying the standard SLN algorithm for sampling.ConclusionSLN mapping algorithm with blue dye single labelling in early endometrial cancer, by identifying LN most likely to be metastatic enabling their selective removal may help avoid routine lymphadenectomies without compromising oncological safety. The procedure is simple and can be practiced at all centres and can also aid pathologists by pinpointing the likely metastatic nodes after a selective or complete lymphadenectomy.  相似文献   
14.
腹腔镜超声刀在妇科恶性肿瘤淋巴结切除术中的应用   总被引:7,自引:0,他引:7  
目的:探讨在妇科恶性肿瘤腹腔镜淋巴结切除术中使用超声刀切割,止血的效果。方法:应用超声刀进行妇科恶性肿瘤腔镜盆腔及腹主动脉周围淋巴结切除术共13例,其中子宫颈癌10例,子宫内膜癌3例,手术步骤包括经阴道腹腔镜辅助广泛全子宫切除,盆腔及腹主动脉周围淋巴结切除和卵巢动静脉高位结扎,并与同期应用电刀切割和止血的相同术式进行比较。结果:使用超声刀较电刀切割和止血术中出血量明显减少(P<0.05),手术时间显著缩短(P<0.05),无术中及术后并发症。结论:腹腔镜下应用超声刀切割和止血具有手术时间短,止血效果更佳,对周围组织无损伤且并发症少等优点。  相似文献   
15.
Zusammenfassung Berichtet wird über die operative Behandlung von 1232 Patienten mit einem kolorektalen Karzinom aus dem Zeitraum 1.09.1984 bis 1.01.1990. Entsprechend einer Resektionsquote von 90,3 % wurden 1112 Patienten (kurativ: n = 917, palliativ: n = 195) reseziert. Bei 82 Patienten war wegen Organüberschreitung des Tumors eine multiviszerale Resektion von einem oder mehreren benachbarten Organen (69mal kurativ, 13mal palliativ) notwendig. Komplikationsraten (26,7% zu 27,5 %) und die 30-Tageletalität (3,4% zu 2,9 %) waren in beiden Gruppen der kurativ and kurativ erweitert resezierten Patienten gleich. Die Berechnung der Fünfjahresüberlebensrate ergab für die kurativ resezierten Patienten ohne Erweiterung einen Wert von 58% gegenüber 55 mit Erweiterung. Auch die Subgruppenanalyse ergab keinen Unterschied in den einzelnen Stadien. Die Ergebnisse lassen den Schlul zu, da bei gleicher Komplikations-und Letalitätsrate die kurativ erweiterte Resektion von pT3- and pT4-Tumoren gleiche Spdtergebnisse wie die entsprechende Behandlung von nicht erweitert resezierten pT3-Tumoren erwarten lät. Die Daten zeigen, da eine Infiltration von Nachbarorganen durch ein kolorektales Karzinom nicht als Inoperabilitätskriterium gelten darf.
From 1 September to 1 January 1990, a total of 1232 patients underwent surgery for colorectal cancer. Resection was performed on 1112 (90.3%) patients. It was curative in 917 cases and palliative in 195. Multivisceral resection was necessary 82 times because of tumour infiltration of adjacent organs (curative: 69 cases; palliative: 13 cases). The complication rate (26.7% vs 27.5%) and mortality rate (3.4% vs 2.9%) were similar to those for curative resections without multivisceral extension. The 5-year survival rate was also similar in the two groups (58% vs 55%). These results show that curative multivisceral resections can lead to the same long-term results as conventional curative resections. These data are encouraging, and tumour infiltration of neighbouring organs should not be taken to demonstrate inoperability.
  相似文献   
16.
A large linear flow range and a small instrumental dead space volume are incompatible properties for a pneumotachometer (PTM). The linearity of a Fleisch number 2 PTM is studied for flows up to 6 litre s-1 (nominal range 0-2 litre s-1) with various up- and downstream geometries. It is hypothesised that using an array of calibration factors (conductance; flow/pressure), instead of a single calibration factor over the entire flow range, could improve accuracy and also extend the applicable flow range. The conductance against pressure characteristics are calculated with a previously described weighted averaging technique based on multiple strokes from a precision syringe. A single conductance value gives stroke volume errors in the range of -5 to 3% (0-2 litre s-1) and -6 to 11% (0-6 litre s-1) for validation using the same geometry as for calibration. The pressure dependent conductance improves accuracy to within -3% and 1% independent of flow range. However, for validation using a different geometry than for calibration, errors range from -5% to +8%. The degree of non-linearity varies between the geometries (range 3-15%) and is highest when using a one-directional valve upstream of the PTM and a Y-shaped connector. In conclusion, a pressure-dependent conductance improves accuracy and can also be used to extend the applicable flow range up to at least three times the nominal flow range.  相似文献   
17.
A comparative study of perinatal mortality patterns over a period was conducted at a teaching hospital of South India. Among the 6,048 babies born from January 1984 to December 1985 (Group A), there were 265 (43.8/1000) still births and 127 (22.0/1000) early neonatal deaths. Three hundred and thirty seven (41/1000) babies were still born and 235 (29.8/1000) early neonatal deaths out of 8,215 deliveries during 1992–93 (Group B). The perinatal mortality rate (PMR) in Group A and B were 57.9/1000 and 57.7/1000 respectively. Unbooked cases accounted for the majority (> 75%) of perinatal deaths during both the periods. The overall mortality rates in unbooked cases were three to four times higher than booked cases. Among the various causes of still births, antepartum haemorrhage and uterine rupture had increased. Septicaemia was the major cause of early neonatal deaths in Group A, but in Group B birth asphyxia and prematurity were the leading causes. Effective interventions like creating awareness among the target population to utilise maternal and child health services and early referral of high risk cases with improved intranatal and perinatal care can decrease the perinatal mortality.  相似文献   
18.
目的探讨卵巢癌复发的可能相关因素及治疗方法.方法卵巢癌患者101例,分为复发组36例及对照组65例,比较两组患者孕产史、肿瘤及妇科肿瘤家族史、腹水细胞学阳性率及手术时淋巴结清扫有无显著性差异.结果复发组与对照组平均妊娠次数、生育次数及手术时淋巴结清扫等两组比较差异无显著性;而两组比较妇科肿瘤家族史16.7%(6/36)和4.6%(3/65)P<0.05;两组Ⅰ~Ⅱ期患者腹水细胞学阳性率80.0%(4/5)和26.3%(5/19),P<0.01,两组比较差异有显著性.结论卵巢癌患者的妇科肿瘤家族史及腹水细胞学阳性率与卵巢癌的复发有一定的相关性,而手术范围是否包括淋巴结清扫与肿瘤复发无关.  相似文献   
19.
Baiocchi G, Raspagliesi F, Grosso G, Fontanelli R, Cobellis L, di Re E, di Re F. Early ovarian cancer: Is there a role for systematic pelvis and para-aortic lymphadenectomy? Int J Gynecol Cancer 1998; 8 : 103–108.
In order to focus on the incidence and the clinical significance of lymphatic spread in patients with cancer apparently confined to the ovaries, we present our 20 year experience in a large series of patients with early ovarian cancer who had systematic pelvic and para-aortic lymphadenectomy. A retrospective study of 280 consecutive patients is presented. Systematic pelvic and para-aortic lymphadenectomy was performed in 205 cases (73.2%). Selective sampling and node biopsy were performed in 30 (10.7%) and 7 (2.5%), respectively. Node metastases were found in 32/242 patients (13.2%). The incidence of metastatic nodes was significantly higher in patients with serous adenocarcinomas and/or poorly-differentiated tumors. When few nodes were involved (1–3) lymphatic spread was most ipsilateral to the tumor. Even though the retrospective nature of the study has to be considered, univariate analysis revealed statistically significant differences in 5-year survival based on FIGO stage, histology, grade of differentiation, and node status. By contrast, using multivariate analysis, none of these risk factors was an independent variable for predicting long-term survival. However, node status closely approached the statistically significant level ( P = 0.06). Only prospective and randomized studies can clarify the role of lymphadenectomy in early ovarian cancer. However, while awaiting these results, this surgical procedure should be a part of a research protocol.  相似文献   
20.
Background. In Japan, much attention has recently been paid to super-extended paraaortic lymphadenectomy (PAL) for the treatment of advanced gastric cancer. However, it has been reported that PAL is associated with increased morbidity and mortality, as compared to conventional extended lymphadenectomy (D2 or D3). Therefore, an analysis of the effects of PAL on perioperative changes in the biological responses of patients essential for determining the potential utility of this procedure. Methods. The current non-randomized prospective study included evaluations of perioperative changes in parameters of surgical stress (series I; serum levels of antidiuretic hormone, interleukin-6, trypsin, and phospholipase A 2 ) and immunocompetence (series II; phytohemagglutinin- and concanavalin A-induced blastogenesis, activity of natural killer cells and the ratio of CD4 cells to CD8 cells) in patients with advanced gastric cancer (T3 or T4), comparing groups treated with D3 plus PAL ( n = 12) and D3 ( n = 13), and a control group with early gastric cancer ( n = 16) treated with D1 lymphadenectomy (perigastric N1 nodes) between April 1995 and April 1997. Results. The duration of surgery and the amount of blood lost were longer and greater in the D3 plus PAL group than in the D3 and D1 groups. D3 plus PAL and D3 were associated with significant postoperative increases in parameters of surgical stress, as well as with significant postoperative immunosuppression, compared to results with D1. However, there were no significant differences in the respective parameters between the D3 plus PAL and D3 groups. Conclusions. Our results indicate that there are no essential differences in patients' biological responses between D3 plus PAL and D3 lymphadenectomy. It appears that PAL-associated morbidity can be minimized by very careful manipulation during the dissection of paraaortic lymph nodes. Received for publication on Feb. 10, 1998; accepted on Jun. 3, 1998  相似文献   
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