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101.
To compare the results of laparoscopy with laparotomy in the management of ovarian masses not suspected of being malignant, a retrospective review was made of 115 patients with ovarian masses operated on, 50 by laparotomy and 65 by laparoscopy, in the Department of Obstetrics and Gynaecology, Prince of Wales Hospital, Hong Kong, from November 1, 1992, to October 31, 1993. In the laparoscopy group, the average size of the ovarian masses was smaller, and there was a significant reduction in the intraoperative blood loss, postoperative analgesic requirement, morbidity (particularly febrile morbidity and urinary retention), length of hospital stay, and recuperation period. The incidence of rupture of the ovarian mass was not related to the operative approach but to the underlying pathology. Two patients in the laparoscopy group were converted to laparotomy, and 1 in the laparotomy group required a second laparotomy. The operating time was longer in the laparoscopic approach, but this could be reduced with experience and improved technique in specimen removal. Laparoscopy appears to be a better approach than laparotomy in the management of ovarian masses where malignancy is not suspected and a competent surgeon is available.  相似文献   
102.
The aims of this study were to determine (1) whether acute suppression of bone formation could be evaluated after the administration of corticosteroids in man by quantitative bone histomorphometry; and (2) whether there were significant differences between the effects of prednisone and its analog deflazacort. Thirteen patients who needed high-dose corticosteroid therapy were randomly allocated to two groups of treatment (prednisone or deflazacort). Quantitative bone histomorphometry, using the technique of triple labeling, and biochemical measurements of bone turnover were studied. There were no differences in biochemical indices of bone turnover between prednisone and deflazacort at the beginning and end of the 15 days of treatment course. During corticosteroid treatment, there were no significant changes in biochemical indices of bone turnover but a significant decline in total alkaline phosphatase (P<0.01). Histomorphometric indices, as revealed by measurements of tetracycline interval and extent of labeling, showed no significant differences in either mineral apposition rate or bone formation rate in the two groups. We conclude that the acute glucocorticoid suppression of bone turnover by glucocorticoids is not detectable within the first 2 weeks of treatment by histomorphometric techniques. No differences in bone effects of prednisone and deflazacort were detected in this short-term study.  相似文献   
103.
目的:探讨细胞凋亡及增殖细胞核抗原(PCNA)与子宫颈癌的关系。方法:采用原位末端标记法(TUNEL)检测细胞凋亡,采用免疫组化技术检测PCNA和P53蛋白。结果:32例子宫颈鳞癌组织中,细胞凋亡、P53蛋白和PCNA阳性率分别为62.50%,53.13%和65.63%。表达P53蛋白的细胞与表达PCNA细胞分布区域基本一致,与细胞凋亡无明显相关性。正常子宫颈组织只有上皮组织内有少数凋亡细胞和表达PCNA的细胞,显微镜下每视野阳性细胞数均不超过10%。结论:P53蛋白可能通过促进细胞增殖,抑制细胞凋亡而参与子宫颈癌发生与发展。  相似文献   
104.
OBJECTIVE: To analyze hospitalization patterns of persons with AIDS (PWAs) in a multi-state/multi-episode continuous time duration framework. DATA SOURCES: PWAs on Medicaid identified through a match between the state's AIDS Registry and Medicaid eligibility files; hospital admission and discharge dates identified through Medicaid claims. STUDY DESIGN: Using a Weibull event history framework, we model the hazard of transition between hospitalized and community spells, incorporating the competing risk of death in each of these states. Simulations are used to translate these parameters into readily interpretable estimates of length of stay, the probability that a hospitalization will end in death, and the probability that a nonhospitalized person will be hospitalized within 90 days. PRINCIPAL FINDINGS: In multivariate analyses, participation in a Medicaid waiver program offering case management and home care was associated with hospital stays 1.3 days shorter than for nonparticipants. African American race and Hispanic ethnicity were associated with hospital stays 1.2 days and 1.0 day longer than for non-Hispanic whites; African Americans also experienced more frequent hospital admissions. Residents of the high-HIV-prevalence area of the state had more frequent admissions and stays two days longer than those residing elsewhere in the state. Older PWAs experienced less frequent hospital admissions but longer stays, with hospitalizations of 55-year-olds lasting 8.25 days longer than those of 25-year-olds. CONCLUSIONS: Much socioeconomic and geographic variability exists both in the incidence and in the duration of hospitalization among persons with AIDS in New Jersey. Event history analysis provides a useful statistical framework for analysis of these variations, deals appropriately with data in which duration of observation varies from individual to individual, and permits the competing risk of death to be incorporated into the model. Transition models of this type have broad applicability in modeling the risk and duration of hospitalization in chronic illnesses.  相似文献   
105.
Familial neuroblastoma occurs rarely. We studied a family with three children; one of them has a disseminated (stage 4) and another has a localized (stage 2) neuroblastoma. We observed subtelomeric locus D1Z2 (1p36) deletion in both tumors by using double-color fluorescence in situ hybridization. The MYNC gene was found in single copy in both tumors. Loss of heterozygosity (LOH) and restriction fragment length polymorphism analyses were performed by using DNA from frozen tumor cells and from microdissected tumor areas excised from paraffin-embedded sections. We detected somatic LOH at locus D1S468 (1p36) in a tumor-cell population with a trisomy 1 of the stage-2 patient. Neuroblastoma cells of the stage-4 patient were diploid and showed allelic loss at the following loci: D1S172, D1S80, D1S94, D1S243, D1S468, D1S214, D1S241, and D1S164. Haplotype study showed that the siblings inherited the same paternal 1p36-->pter chromosome region by homologous recombination and that, in the two tumors, arm 1p of different chromosomes of maternal origin was damaged. Our results suggest that the siblings inherited the predisposition to neuroblastoma associated with paternal 1p36 region and that tumors developed as a consequence of somatic loss of the maternal 1p36 allele.  相似文献   
106.
Ho SL  Cheng PW  Wong WC  Chan FL  Lo SK  Li LS  Tsang KL  Leong LL 《Neurology》1999,53(9):2132-2139
BACKGROUND: Neurovascular contact (NVC) with the root exit zone (REZ) of the ipsilateral facial nerve is associated with hemifacial spasm (HFS), but unresolved issues remain. OBJECTIVES: To 1) determine the frequency of symptomatic and nonsymptomatic NVC, 2) determine the features of NVC associated with HFS, and 3) correlate severity of HFS to these features. METHODS: Two independent, blinded, prospective assessments of high-resolution MR and MR angiography (MRA) images were performed on Chinese cases (HFS: n = 44; age-matched control subjects: n = 20). RESULTS: Over 88% of 44 symptomatic sides in patients with HFS had NVC of the ipsilateral facial nerve. At least 80% of symptomatic sides involved NVC at the anterior aspect of the REZ [REZ(ant.)]. Although NVC was observed in approximately half of nonsymptomatic sides, at least 70% of them were not at REZ(ant.). NVC at the cisternal and intracanalicular portions of the facial nerve were not associated with HFS. Half of our patients with HFS had bilateral NVC, but none had bilateral symptoms. Most of our MR/MRA images showed that the size and position of the arterial branches of the vertebrobasilar system were markedly asymmetric. Of patients with bilateral NVC, over 83% had asymmetric NVC sites. The anterior inferior cerebellar artery was the most common vessel involved in NVC, but was not significantly associated with HFS. Most of the NVC involved one vessel at one contact point with no indentation. The development of HFS was significantly associated with nerve indentation in NVC. The development and severity of HFS were not associated with multiple contact points in NVC. No significant interobserver variability existed between the blinded assessments. CONCLUSIONS: MRI/MR angiography are accurate, fast, and safe in characterizing neurovascular contact (NVC) at the brainstem. The site of NVC and ipsilateral facial nerve indentation in NVC are significant determinants for the development of hemifacial spasm (HFS). The lack of bilateral NVC at the anterior aspect of the root exit zone of the facial nerve could explain in part the lack of bilateral symptoms. The development and severity of HFS are not associated with a specific blood vessel or multiple contact points in NVC.  相似文献   
107.
The overlapping expression of neurotrophin and neural cytokine receptors indicates that most neuronal populations are responsive to both classes of factors, yet relatively little is known about how these two trophic signaling systems interact to regulate neuronal phenotype. We report here that one hallmark of NGF's effects on target cells, the induction of membrane electrical excitability, requires the intermediary action of a CNTF-like factor. We found that NGF's regulation of voltage-gated potassium channels, unlike its regulation of voltage-gated sodium and calcium channels, involves a CNTF-like autocrine/paracrine loop. We showed that NGF induces secretion of a soluble factor that mimics the action of exogenous CNTF in regulating voltage-gated potassium channels and that NGF's ability to regulate this potassium channel is blocked by three independent reagents that inhibit the signaling of CNTF and/or related factors. The identity of this autocrine factor does not appear to be CNTF itself. Thus, a CNTF-like autocrine/paracrine factor is both necessary and sufficient for the regulation of potassium channels by NGF and is a key determinant of the type of electrical excitability that NGF induces in target cells.  相似文献   
108.
Lee SM  Yip PK  Jeng JS  Lo HJ  Chang M 《Psychiatry research》1999,92(2-3):93-102
Although many regional cerebral blood flow (rCBF) studies of schizophrenic patients have been carried out, only a few studies have investigated real-time hemodynamic changes in schizophrenic patients. In the present study, we used long-term monitoring of the middle cerebral artery (MCA) by non-invasive transcranial Doppler ultrasonography to obtain real-time CBF data in 55 schizophrenic patients and 20 normal comparison subjects. The mean blood flow velocity and pulsatility index (PI) of the MCA were not constant during long-term monitoring. They showed sinusoidal oscillations similar to those described in previous reports. The amplitude variations of these oscillations in both drug-naive and medicated schizophrenic patients were significantly decreased compared with findings in normal control subjects. The averaged PI values were found to be decreased in patients with illness durations of more than 10 years. After withdrawal of antipsychotic medication, both the amplitude variations of oscillations and the PI values in the drug-withdrawn patients were significantly decreased relative to findings in normal control subjects. Our results show a decreased adjustment ability of cerebral vessel resistance not only in neuroleptic-naive schizophrenic patients but also in patients with longer illness duration. Neuroleptics could affect the adjustment ability of vessel resistance.  相似文献   
109.
Ten patients with myotonic muscular dystrophy (MD) were examined by auditory event-related potentials (P300 ERPs), spirometric and blood gas analyses: arterial oxygen tension (PaO2), arterial carbon dioxide tension (PaCO2) and arterial oxygen saturation (SaO2). The aim of the study was to analyse the frequency of ERP abnormalities in this disease and to determine whether the neurophysiological evidence of cognitive impairment might be related to the ventilatory function abnormalities frequently described in MD. The mean P300 latency was significantly altered in MD patients compared with controls; P300 latencies did not correlate with spirometric parameters, blood gas values or with age, age at onset, duration or clinical status of the disease. This study provides neurophysiological evidence of cognitive impairment in MD patients. The cognitive deficits are not related to alveolar hypoventilation and appear to be a non progressive feature of the disease.  相似文献   
110.
Isoeugenolol (1.0, 3.0, 5.0 mg/kg, i.v.) produced a dose-dependent bradycardia and a decrease in blood pressure in anesthetized Wistar rats. Isoeugenolol inhibited the tachycardia effects induced by (-)isoproterenol, but had no blocking effect on the arterial pressor responses induced by (-)phenylephrine. In isolated guinea pig tissues, isoeugenolol antagonized (-)isoproterenol-induced positive inotropic and chronotropic effects on the atria and tracheal relaxations in a concentration-dependent manner. The apparent pA2 values for isoeugenolol on right atria, left atria and trachea were 7.63+/-0.03, 7.89+/-0.12 and 6.12+/-0.05, respectively, indicating that isoeugenolol was a highly selective beta1-adrenoceptor blocker. On the other hand, isoeugenolol produced a mild direct cardiac depression at high concentration and was without intrinsic sympathomimetic activity (ISA). In isolated rat thoracic aorta, isoeugenolol relaxed more potently the contractions induced by (-)phenylephrine (10 microM) and 5-HT (10 microM) than those by high K+ (75 mM). In isolated guinea pig trachea, isoeugenolol attenuated the carbachol (1 microM)-con-tracted trachea more significantly than those contracted with high K+. Furthermore, the binding characteristics of isoeugenolol and various beta-adrenoceptor antagonists were evaluated in [3H]CGP-12177 binding to rat ventricle, lung and interscapular brown adipose tissue (IBAT) membranes. The -log IC50 values of isoeugenolol for predominate beta1-, beta2- and beta3-adrenergic receptor sites were 5.82+/-0.09, 4.74+/-0.05 and 4.73+/-0.12, respectively. In conclusion, isoeugenolol was found to be a highly selective beta1-adrenoceptor antagonist with tracheal and vascular smooth muscle relaxant activities, but was devoid of alpha-adrenoceptor-blocking action.  相似文献   
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