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21.
Nitric oxide and estrogen have been shown to play a critical role in the control of female reproductive function. In order to determine an anatomical relationship between nitric oxide generating neurons and estrogen target neurons, NADPH-diaphorase histochemistry was combined with estrogen receptor immunohistochemistry in the female medial preoptic area. While only a few weakly stained neurons for NADPH-diaphorase were found in ovariectomized control rats, a drastic increase in NADPH-diaphorase activity was observed in the medial preoptic nucleus of estradiol-treated ovariectomized animals. The total number of NADPH-diaphorase neurons in the estradiol-treated group increased three-fold relative to controls, and more than 80% of those neurons contained estrogen receptor-immunoreactivity in their nuclei. Since neuronal NADPH-diaphorase is nitric oxide synthase, the present result suggests that nitric oxide synthase activity can be positively regulated by estradiol in neurons containing estrogen receptor in the female medial preoptic nucleus.  相似文献   
22.
BP神经网络是目前应用最广泛的人工神经网络模型,本文详细阐述了BP神经网络的原理和特点,并论述了其在药学研究中的应用。  相似文献   
23.
The chemokines, macrophage inflammatory protein-1 (MIP-1) and its subunit MIP-1β, induce an intense fever in the rat when they are injected directly into the anterior hypothalamic, pre-optic area (AH/POA), a region containing thermosensitive neurons. The purpose of this study was to compare the central action on body temperature (Tb) of MIP-1β with that of interleukin-6 (IL-6), which also has been implicated in the cerebral mechanism underlying the pathogenesis of fever. Following the stereotaxic implantation in the AH/POA of guide cannulae for repeated micro-injections, radio transmitters which monitor Tb continuously were inserted intraperitoneally in each of 15 male Sprague-Dawley rats. Each micro-injection was made in a site in the AH/POA in a volume of 1.0 μl of pyrogen-free artificial CSF, recombinant murine MIP-1β, or recombinant human IL-6. MIP-1β in a dose of 25 pg evoked an intense fever characterized by a short latency, a mean maximum rise in Tb of 2.4 ± 0.21°C reached by 3.7 ± 0.42 hr, and a duration exceeding 6.5 hr. Injected into homologous sites in the AH/POA, IL-6 induced a dose dependent fever of similar latency and a mean maximal increase in Tb of 1.2 ± 0.25°C, 1.8 ± 0.15°C, and 2.1 ± 0.22°C and duration of 6.2 ± 1.28 hr, 6.7 ± 0.49 hr, and 6.8 ± 0.65 hr when given in doses of 25, 50, and 100 ng, respectively. These results show that MIP-1β and the highest dose of IL-6 induce a fever of comparable intensity, but MIP-1β exerts its action in a much lower concentration. Thus, the de novo synthesis and subsequent action of the MIP-1 family of cytokines on neurons of the AH/POA in response to a pyrogen challenge apparently play a functional role in the pathogenesis of fever. Further, the endogenous activity of IL-6 in the hypothalamus which is enhanced in response to a lipopolysaccharide also may reflect its essential part in the acute phase response to a bacterial challenge. Copyright © 1994 Wiley-Liss, Inc.  相似文献   
24.
The guinea pig maximization test (GPMT) has proven to be a valuable tool for the identification of the skin sensitization potential of chemicals. The method identifies a hazard which can lead in the EC to compulsory labelling of that chemical. In the present study, data on sulphanilic acid derived from the GPMT has been compared with results from a second guinea pig assay (the cumulative contact enhancement test) and the murine local lymph node assay, both of which require only topical application of chemical. Except for the GPMT, no test identified any sensitizing activity associated with exposure to sulphanilic acid. These latter results are consistent with the experience gained from substantial human exposure in an occupational setting and from which no cases of allergic contact dermatitis to sulphanilic acid have arisen over a 20-year period. In consequence, it is questioned which test protocol in practice has given the more accurate identification of sensitization hazard relevant to man.  相似文献   
25.
Summary: It is not generally appreciated that intractable seizures involving the face area are amenable to surgical treatment. Twenty patients with onset of sensorimotor seizures in the face area of the pre- and postcentral gyri have been studied and surgically treated since 1948. Seizures started in the face, tongue, or throat, followed by diverse patterns depending on spread of seizure activity. Two patients had epilepsia partialis continua; 6 had either tonic or atonic drop attacks. All patients had pre- and postcentral face area resections, 12 in the dominant hemisphere. In addition, 3 had more extensive postcentral removal, 7 had temporal lobe, and 4 had small separate or contiguous frontal or parietal resection. Because the seizures were not sufficiently reduced by the first operation, 6 required reoperation; 4 of these patients had residual epileptiform activity on electrocorticogram (ECoG) after the first resection. Three patients had new neurologic signs that did not return to the preoperative level, but in 2 of them the deficit related mainly to higher resection in the central area. All but 2 of these 20 patients had at least moderate seizure reduction. Corticectomy can be performed for treatment of seizures arising in the lower central area and usually does not lead to significant permanent neurologic deficit.  相似文献   
26.
The results of external beam radiotherapy for clinically localized adenocarcinorna of the prostate in 448 patients treated in the period 1980–90 were reviewed. The average follow up was 4.9 years. The patients were aged 44–87 years (median 69 years) and all had histopathological evidence of adenocarcinoma by needle biopsy or transurethral resection of prostate. The histopathological grading was: 127 G1; 154 G2; 127 G3; 12 G4; 28 Gx. Clinical staging according to TNM (American Urological Association) was: 29 T0 (A2); 4 T1 (B1); 173 T2 (B2); 176 T3 (C1); 63 T4 (C2); 3 Tx. Routine surgical pelvic lymph node staging was not performed but patients had radiological (computerized tomography scan or lymphogram) nodal staging: 350 N0; 22 N1; 12 N2; 64 Nx. High energy linear accelerator external beam radiotherapy was given by multiple fields to total doses of 50–70 Gy (median 60 Gy). The majority of patients (307, 69%) was treated by a uniform policy under the care of one radiation oncologist (HM). The rates of local and distant failure at 5 years were 10% (s.e. = 2%) and 42% (s.e. = 3%), respectively. The late complication rate at 5 years was 25% (s.e. = 2%), comprising mild 16%, moderate 7% and severe 1.3%. The 5 year overall survival rate was 64% (s.e. = 2%) and the cancer-specific survival rate was 74% (s.e. = 3%). Both histological grade and clinical stage were strongly predictive of overall survival and distant failure. Only histological grade was predictive of local failure. Treatment with external beam radiotherapy for this common cancer resulted in survival and disease control rates that compare favourably with other published radiotherapy series and has been accompanied by acceptably low morbidity.  相似文献   
27.
Based on the fuzzy characteristic of the pulse state and syndromes differentiation thinking mode of TCM, an information fusing recognition method of pulse states based on SFNN (Stochastic Fuzzy Neural Network) is presented in this paper. With the learning ability in parameters and structure, SFNN fuses the measurement information of three pulse-state sensors distributed in Cun, Guan, and Chi location of body for the pulse state recognition. The experimental results show that the percentage of correct recognition with new method is higher than that by single-data recognition one, with fewer off-line train numbers.  相似文献   
28.
Background Many centers use local anesthesia for adult inguinal hernia surgery in the setting of day-case surgery. There are no reports on, or guidelines for, use of anesthesia for inguinal hernia surgery in adolescents. We describe our initial experience with the use of local anesthesia and intravenous sedation for inguinal hernia surgery in adolescents in the setting of a day-surgery facility. Methods The charts of 14 consecutive adolescent patients (aged 12–17) who had inguinal hernia surgery from July 2004 to March 2005 were reviewed retrospectively. Intravenous sedation was administered 1–3 min before injection of local anesthetic. Sedation consisted of midazolam 0.085 mg kg−1 and either fentanyl 0.85 μg kg−1 or ketamine 0.085 mg kg−1, according to the preference of the anesthesiologist. Additional sedation with half the initial dose was administered if required. Local anesthesia using a combination of lignocaine and bupivacaine was administered by the surgeon with infiltration in the skin and deep tissues. Results Fourteen adolescents aged 12–17 years (mean 14.8 ± 1.37), weighing 34–100 kg (mean 61.2 ± 16.5), had 15 inguinal hernia repairs with sedation and local anesthesia. All the patients were male. All completed the surgery with sedation and local anesthesia. None required conversion to general anesthesia. There were no immediate or subsequent complications. Mean time from the end of surgery to discharge home was under 2 h (mean 106 ± 36 min). Examination of patient charts did not reveal any complaints regarding the surgery or the postoperative course at the postoperative follow up visit. Conclusions The use of local anesthesia with intravenous sedation for inguinal hernia repair in the adolescent age group seems feasible and requires further prospective study.  相似文献   
29.
30.
BACKGROUND: Digital computer analysis of dermatoscopical images has been reported to facilitate the differential diagnosis of pigmented skin lesions in recent years. OBJECTIVE: The aim of our study was to perform digital computer analysis of a set of different melanocytic lesions and compare the objective results. METHODS: The set of 260 melanocytic lesions (150 excised difficult cases (46 melanomas, 47 atypical nevi, 57 common nevi and 110 unexcised common nevi) was automatically analysed by the digital dermatoscopical system microDERM. We searched for differences in asymmetry, size, compactness and colour distribution. Perimeter/area ratio was calculated. RESULTS: The perimeter/area ratio was detected as the most important criterion for differentiation between malignant and benign melanocytic lesions (sensitivity 91.3% and specificity 90.7% for malignant melanomas vs. all benign nevi; sensitivity 91.3% and specificity 80.8% for melanomas vs. clinically atypical nevi). Differences in size of the lesion, shape and asymmetry of colour were found and statistically verified. Using step-wise logistic regression the formula for calculation of probability of malignant nature of every analysed lesion was constructed. CONCLUSION: The perimeter/area ratio is a simple parameter for the differential diagnosis of melanocytic skin lesions.  相似文献   
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