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31.
目的探讨在肝肥大-萎缩征中肥大肝叶内胆管结石的处理方法。方法回顾性分析我科1990年6月~2004年12月收治的103例肥大肝叶内胆管结石病人的临床资料,总结其手术治疗的原则和方法。结果全体病例均经手术治愈,术后残石率17.5%,效果优良率83.7%。结论肥大肝叶内的胆管结石,手术难度大,应根据病情选择手术方式,既要遵循肝胆管结石的治疗原则,又要保护赖以生存的肥大肝叶(段)。  相似文献   
32.
BACKGROUND: During formation of prolactin neoplasia, how cells and its structure in adenohypophysis affect prolactin cells should be further studied. Intermediate lobe can be regarded as a driving region to release prolactin (PRL) and may promote formation of prolactin neoplasia in pituitary anterior lobe. OBJECTIVE: To observe the effect of diethylstilbestrol (DES) on the expressions of μ and m-calpains in pituitary intermediate lobe of female Wistar rats. DESIGN: Observational contrast animal study. SETTING: Beijing Neurosurgical Institute. MATERIALS: A total of 21 female Wistar rats, 3 weeks old weighing 70–80 g were housed with free access to tap water and standard pellet food. They were kept in a CL-grade condition, at (24±1)℃ and a humidity of (55±5)%, and with a 12 hours day-night cycle. Caprine anti-μ- and m-calpains antibodies were provided by Santa Cruz Biotechnology, CA, USA; rabbit-anti-PRL antibodies by Dako, Denmark; rabbit-anti-ACTH antibody by Boster Company, Wuhan. METHODS: The experiment was carried out in Pathophysiological Department and Animal Laboratory, Beijing Neurosurgical Institute from August 2006 to January 2007. ① Rats were randomly divided into groups with 7 in each group, including vehicle control group, in which rats were injected intraperitoneally with sun-flower seed oil (1 mL/kg, twice a week) for 16 weeks; DES group, where animals were administered with DES (5 mg/kg, twice a week) for 16 weeks; DES + vehicle control group, in which DES was administered for 12 weeks at the same dose with those in DES group, and then was discontinued and replaced by sun-flower seed oil (1 mL/kg, twice a week) for the following 4 weeks. ② At 16 weeks later, pituitary tissue was dealt with HE staining and PRL immunohistochemical examination to observe evoke of tumor; meanwhile, immunohistochemical examination was used to observe expression of PRL of pituitary anterior lobe, expressions of μ- and m-calpains of pituitary intermediate lobe and distribution of adrenocorticotropin. MAIN OUTCOME MEASURES: ① Expression of PRL of pituitary anterior lobe, expressions of μ- and m-calpains of pituitary intermediate lobe and distribution of adrenocorticotropin. ② Morphological observation of pituitary tissue. RESULTS: All 21 rats were involved in the final analysis. ① Results of immunohistochemical examination: Morphological changes of neoplasia in DES group were strongly positive to PRL, and this suggested that formation of prolactin adenoma was observed in pituitary tissue. As compared with vehicle control group, expression of adrenoeorticotropic hormone (ACTH) was increased in both DES group and DES + vehicle control group. In addition, expressions of μ- and m-calpains in pituitary intermediate lobe were higher in DES group than that in vehicle control group. Otherwise, expressions of m-calpains in pituitary intermediate lobe was decreased in DES + vehicle control group, but expression of μ-calpains was still increased. ② Morphological observation of pituitary tissue: Gland tubes were orderly arranged in rats in vehicle control group. Anterior pituitary gland in rats of DES group demonstrated an apparent disappearance of gland tubes and a relatively large-scaled vasculature formation, namely the vascular lake lined by tightly arranged endothelial cells. Local integrated tumor cell arrangements were also detected. In addition, the border between the IL and the anterior lobe was locally blurred. The definite tumor-like changes in pituitary tissues were confirmed in 6 of 7 female Wistar rats in DES group, and one spontaneous occurrence of tumor formation was found in vehicle control group. In DES + vehicle control group, DES withdrawal led to the subtile emergence of gland tube cavity, although tumor-like cells still existed in 4 of 7 rats, suggesting occurrence of the tumor regression due to the withdrawal of DES. CONCLUSION: A long-term application of DES can enhance the expressions of ubiquitours neutral cysteine protease in pituitary intermediate lobe and this suggests that both of them play a key role in release of hormone and formation of prolactin neoplasia through directly promoting PRL expression and release of neighboring pituitary intermediate lobe.  相似文献   
33.
Summary: Purpose: We wished to identify immunocytochemically the distribution of proopiomelanocortin-related peptides in the hippocampal formation of patients with epilepsy.
Methods: Surgical hippocampal specimens from temporal lobe epilepsy (TLE) patients and autopsy control tissue were examined immunocytochemically for ACTH, α-melanocyte-stimulating hormone (α-MSH) and α-endorphin.
Results: There was a dense distribution of ACTH-immunoreactive neurons in the hippocampal formation of patients with mesial TLE syndrome (MTLE). These hippocampal specimens showed significant cell loss. ACTH-positive neurons were most prominent in the subiculum, with scattered ACTH-immunoreactive neuronal elements distributed in the cornu ammonis fields and hilus. Light ACTH immunoreactivity was detected in the tumor-related epileptic hippocampal specimens, which showed minimal cell loss. Although autopsy control tissue from the hypothalamus showed intense ACTH staining patterns in cells and fibers, there was little or no ACTH immunoreactivity in the autopsy hippocampal tissue. The expression of ACTH immunoreactive elements was correlated with patterns of cell loss. No α-MSH- or β-endorphin-immunoreactive neurons were detected in any of the hippocampal specimens.
Conclusions: ACTH has anticonvulsant properties, and its novel expression in the glutamatergic subicular neurons, which provide the main outflow of the hippocampal formation, may represent an attempt by the damaged hippocampal circuit to restore the balance of excitatory/inhibitory neurotransmission in TLE.  相似文献   
34.
Equating the condition after cardiac arrest with that of medial temporal damage, and consequently medial temporal lobe amnesia, is questioned on the basis of results from a patient who was studied neuropsychologically as well as with static and dynamic imaging methods (MRI, PET) 6–9 months after a heart attack. The patient manifested severe and persistent anterograde and retrograde amnesia, as well as further cognitive deteriorations. While MRI only indicated non-specific cortical atrophy, PET revealed a severe bilateral affection of the thalamus and of both medial and lateral temporal cortices as well as occipito-parietal hypometabolism. The neuropsychological status indicates that patients with a diagnosis of cardiac arrest may suffer very severe and persistent cognitive deficits; the imaging analyses show that cardiac arrests may lead to quite severe and widespread brain damage which, however, may not be visible with current magnetic resonance imaging technology, but which is clearly apparent from positron emission tomography. These data suggest that patients with a condition after a heart attack may not be valid models for pure hippocampal—or even medial temporal lobe—pathology, as they may suffer much more widespread brain damage.  相似文献   
35.
Abstract  To determine whether there are metabolite changes in the left medial temporal and frontal lobes with aging, we performed proton magnetic resonance spectroscopy in 36 normal subjects. The N-acetylaspartate/creatine-phosphocreatine ratio in the medial temporal lobe tended to be decreased in subjects over 60 years of age. The ratio decrease in the frontal lobe related to aging was lower than that in the medial temporal lobe. There were no significant differences in the metabolite ratios between males and females. These findings suggest that structures in the medial temporal lobe may be more susceptible to neuronal dysfunction associated with aging than those in the frontal lobe.  相似文献   
36.
Summary: Purpose: Sphenoidal electrode (SE) insertion can cause pain, for which local anesthesia with lidocaine or intravenous administration of fentanyl has been advocated by different epilepsy treatment centers. Transient facial palsies have been observed after SE insertion. Their frequency of occurrence, distribution, and duration have not been well characterized, however. We hypothesized that this complication is due to the effect of local anesthesia on the peripheral branches of the seventh cranial nerve. To test this hypothesis, we compared the incidence and characteristics of facial palsy during SE insertions performed with either local anesthesia or after intravenous fentanyl administration.
Methods: We performed a retrospective study in two patient groups. Group A consisted of 25 patients aged 28 ± 8·2 years who underwent a prolonged video-EEG (VEEG) monitoring study with SE after subcutaneous infusion of 1% lidocaine in the insertion area. Group B included 25 patients aged 30·1 ± 8·9 years whose SE were inserted after intravenous administration of 100-200 μ fentanyl. Blood pressure (BP) was monitored every 3-5 min throughout the procedure.
Results: Five patients (20%) from group A had a transient facial palsy; in 4, it was complete and in 1 it was partial; 1 patient had a bilateral facial palsy. Paresis lasted 1-7 min (mean 3·2 min). In all patients, the recovery was complete. None of the patients in group B had complications (p = 0·025, Fisher's exact test).
Conclusions: Transient facial palsy is a relatively frequent complication of SE insertion when SE are placed under local anesthesia; patients should be forewarned of its possible occurrence.  相似文献   
37.
Reproduction stops among the majority of prairie voles (Microtus ochrogaster) during the winter. Short day lengths suppress male reproductive function dramatically in the laboratory, but photoperiod exerts only subtle effects on female reproductive function. Thus, the regulation of seasonal breeding in this species remains partially unspecified. In contrast to commonly studied rodents, female prairie voles do not undergo spontaneous estrous cycles; rather, they are induced into estrus by exposure to chemosignals expressed in conspecific male urine. In the present study, the hypothesis was tested that seasonal breeding among female prairie voles in the field reflects photoperiod-mediated changes in the responsiveness of the chemosensory system to male urine. Responsiveness was assessed by localizing the product of the c-fos immediate early gene with an immunocytochemical procedure. Female prairie voles were maintained in either long (LD 16:8) or short (LD 8:16) photoperiods from birth until adulthood, and exposed to either male urine or skim milk. Immunocytochemistry forfos protein revealed an increased number of immunoreactive cells within the accessory olfactory system of female prairie voles, including the accessory olfactory bulbs, granule cell layer, as well as the medial and cortical divisions of the amygdala 1 h after exposure to a single drop of urine as compared to individuals exposed to skim milk. The number of immunoreactivefos cells induced in females by conspecific male urine was also affected by photoperiod; short day females displayed fewer immunoreactivefos neurons in the accessory olfactory system as compared to long-day animal. Taken together, these results indicate that similar mechanisms underlie the responses of different rodent species to the chemosignals of conspecifics and that the pattern offos expression observed in the present study has functional significance for the regulation of reproduction in prairie voles.  相似文献   
38.
Objective: Right upper lobe collapse is a common radiographic finding in intubated children. We hypothesized that deep suctioning and uncontrolled negative pressures during endotracheal tube suctioning were significant contributory factors. Methods : The incidence of right upper lobe (RUL) collapse in intubated, ventilated children on a paediatric cardiac intensive care unit was determined over a 3-month period ( n = 102). Graduated suction catheters and suction vacuums of < 165 cm H2O were then introduced. Another prospective audit was carried out 3 months later ( n = 60). Results : We found that 24% developed RUL collapse and 4 developed an apical pneumothorax. Following the introduction of graduated catheters and controlled vacuums pressures, a significant reduction in the incidence of RUL collapse, to 7%, was observed ( p < 0.05). Conclusions : We conclude that high negative pressure and deep-suctioning causes RUL collapse in children. Any lobar collapse not only prolongs the child's stay in intensive care, but can be associated with further morbidity which may have a serious implication. By improving suctioning technique this morbidity can be significantly reduced.  相似文献   
39.
A comprehensive neuropsychological test battery was administered to 10 consecutive patients undergoing neurosurgical intervention, capsulotomy, as a last resort treatment for chronic, incapacitating, and otherwise intractable illness, either obsessive-compulsive disorder (OCD; n= 5) or non-OCD anxiety disorder (n= 5). The aim was to study the neuropsychology of severe anxiety disorders before and after a defined neurosurgical intersection of connections between the frontal lobes and related brain regions. Although extremely disabled by their illness before surgery, the patients performed within the normal range on most tests. After capsulotomy, there was significant improvement on measures of clinical morbidity and of psychosocial functioning, and the general neuropsychological performance remained remarkably intact. In a subgroup of 5 patients, however, perseverative responses were more common postoperatively, possibly indicating dysfunction of systems involving the frontal lobes. Although admittedly sparse, these data can be interpreted as suggesting that in vulnerable individuals, capsulotomy may give rise to increased perseverative behaviour in the laboratory, and possibly in the real world as well. This risk must be weighed against the potential clinical benefit of capsulotomy in this extremely disabled, sometimes suicidal patient population.  相似文献   
40.
A group of cadaveric livers bearing anteroposterior grooves or furrows in the superior surface of the right lobe is described. Such grooves have been noted by others in living patients. The existence of these grooves has been recognized since at least 1888, but there seems to be no agreement as to their cause. It appears from this study that different types of groove or indentation occur, according to their orientation relative to the median plane of the body. Two major groups of theories of causation are recognized, but no firm conclusions are drawn. © 1993 Wiley-Liss, Inc.  相似文献   
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