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991.
A pilot study was conducted using two courses of cis-diamminedichloroplatinum, vincristine (Oncovin), and bleomycin (COB) every three weeks prior to surgery(s) and/or radiotherapy in 34 patients with advanced previously untreated epidermoid cancer of the head and neck. All patients received at least one course of chemotherapy; 7 are too early for evaluation. Responses to chemotherapy were dramatic and occurred within a few days. Sixteen patients had partial remission (PR) (59.3%), 9 had minimal response (MR) (33.3%) and 2 had stable disease after one course of COB. Twenty-two patients completed a second course of chemotherapy, 6 (27.3%) had complete remission (CR), 13 (59.1%) had PR, 1 had MR and 2 had stable disease. Objective remission correlated with subjective improvement. Drug toxicity were tolerable and acceptable. Eight patients had surgical resection after chemotherapy, followed by post-operative radiation therapy, and one patient had pre-operative radiation therapy before the tumor was considered resectable. Twelve patients underwent radiotherapy, including patients with CR after chemotherapy. Presently there is no evidence of local recurrence with the longest follow-up of 15+ months. In this preliminary report, the effectiveness and feasibility of this combined modality therapy is established; further study is needed to prove its value in prolonging disease-free period and survival.  相似文献   
992.
993.
994.
We studied the clinical presentation and management of four patients with anterior urethral valves; a rare cause of urethral obstruction in male children. One patient presented antenatally with oligohydramnios, bilateral hydronephrosis and bladder thickening suggestive of an infravesical obstruction. Two other patients presented postnatally at 1 and 2 years of age, respectively, with poor stream of urine since birth. The fourth patient presented at 9 years with frequency and dysuria. Diagnosis was established on either micturating cystourethrogram (MCU) (in 2) or on cystoscopy (in 2). All patients had cystoscopic ablation of the valves. One patient developed a postablation stricture that was resected with an end-to-end urethroplasty. He had an associated bilateral vesicoureteric junction (VUJ) obstruction for which a bilateral ureteric reimplantation was done at the same time. On long-term follow-up, all patients demonstrated a good stream of urine. The renal function is normal. Patients are continent and free of urinary infections. Anterior urethral valves are rare obstructive lesions in male children. The degree of obstruction is variable, and so they may present with mild micturition difficulty or severe obstruction with hydroureteronephrosis and renal impairment. Hence, it is important to evaluate the anterior urethra in any male child with suspected infravesical obstruction. The diagnosis is established by MCU or cystoscopy and the treatment is always surgical, either a transurethral ablation or an open resection. The long-term prognosis is good.  相似文献   
995.
Hypertensive primary intraventricular hemorrhage due to a phaeochromocytoma   总被引:1,自引:0,他引:1  
Primary intraventricular haemorrhage (IVH) is rare. We defined primary IVH as haemorrhage into the ventricles only as detected by computerized tomographic (CT) brain scan. This is in contrast with other intracerebral haemorrhages (e.g. basal ganglia/thalamic with intraventricular extension). The clinical condition of the patient ranges from minimal neurological deficits to coma/death. It also carries with it a poor prognosis of up to 80% when all four ventricles are involved. We present a 45-year-old Chinese female who presented with a hypertensive IVH which was managed successfully with ventricular drainage and intraventricular urokinase therapy. An adrenal phaeochromocytoma was diagnosed which was subsequently removed laparoscopically. The patient has recovered well in all aspects. This case report will discuss management of IVH and the importance of searching for secondary causes of hypertension.  相似文献   
996.
BACKGROUND: Adequate ovarian response to exogenous gonadotrophins is important for both ovulation induction (OI) and controlled ovarian stimulation (COS). The objective of this study was to analyse the effect of a number of clinical factors that influence ovarian response in non-polycystic ovarian syndrome (non-PCOS) patients. METHODS: A total of 140 OI cycles (52 subjects), where each subject had a single abnormality (elevated FSH, abnormal body mass index (BMI) or > or = 40 years of age), were compared with 54 cycles (15 subjects) where the patients displayed none of these abnormal features (the normal group). Similarly, 275 COS cycles (135 subjects), where each subject displayed a single abnormality, were compared with 79 cycles (40 subjects) in the normal group. RESULTS: For OI, subjects with a high basal FSH generally had an inadequate response with a poor chance of conception. Subjects with an abnormal BMI commonly required dosage adjustment so were more difficult to manage. Their potential for conception was normal. Older women seemed to respond normally with a normal expectation of conception. In the COS group, subjects with a moderately high basal FSH responded and conceived normally. Subjects with an abnormal BMI had an increased risk of an inadequate response leading to cancellation but if the response was adequate then the outlook was good. Older women required more gonadotrophin with a poor response and a low chance of conception. CONCLUSION: The results have better defined the anticipated responses of non-PCOS patients to gonadotrophin stimulation in both OI and COS.  相似文献   
997.
The disability profile of persons with schizophrenia in Singapore and how disability levels vary in patients cared for in the community and in the long-stay wards of a state mental hospital were studied using the Life Skills Profile (LSP). The inter-rater reliability of the LSP assessed by the intraclass correlation coefficient (ICC), was lower than in the Australian studies. The test-retest ICCs for the total LSP score and the five subscale scores were satisfactory for the hospitalised subjects and for the community psychiatric nurse subjects, but generally poor for the community care facility subjects. The average ICCs were lower compared to the Australian study. Female hospitalised subjects but not male hospitalised subjects returned higher disability scores on all LSP scales compared to community subjects. This study provided some preliminary data on the usefulness and validity of the LSP in a multi-ethnic Asian setting like Singapore. If the LSP is used as a measure of disability in schizophrenia, it would appear that ratings should only be made by those who know the subject well, and that raters should be formally trained mental health professionals.  相似文献   
998.
Mice lacking the mu-opioid receptor gene have been developed by a gene knockout procedure. In this study, the activity of opioid receptor coupled G-proteins was examined to investigate whether there is a change in the extent of coupling for mu, delta-, and kappa-opioid receptors in mu-opioid receptor knockout mice. Selective agonists of mu- (DAMGO), delta- (DPDPE), and kappa- (U-69,593) opioid receptors stimulated [(35)S]GTPgammaS binding in the caudate putamen and cortex of wild-type mice. In contrast, only U-69,593 stimulated [(35)S]GTPgammaS binding in these regions of mu-opioid receptor knockout mice. These results confirmed the absence of G-protein activation by a mu-opioid receptor agonist in mu-opioid receptor knockout mice, and demonstrated that coupling of the kappa-opioid receptor to G-proteins is preserved in these mice. However, G-protein activation by the delta-opioid receptor agonist, DPDPE, was reduced in the mu-opioid receptor knockout mice, at least in the brain regions studied using autoradiography.  相似文献   
999.
Epidemiologic studies of childhood leukemia have made limited use of tumor genetic characteristics, which may be related to disease etiology. We characterized the cytogenetics of 543 childhood leukemia patients (0-14 years of age) enrolled in the Northern California Childhood Leukemia Study, an approximately population-based study comprised primarily of Hispanics (42%) and non-Hispanic Whites (41%), and compared the cytogenetic profiles between these two ethnic groups. Subjects were classified by immunophenotype, conventional cytogenetic characteristics, and fluorescence in situ hybridization findings. The ploidy levels most frequently observed among acute lymphoblastic leukemia patients were high hyperdiploidy (51-67 chromosomes) and pseudodiploidy (34% and 27%, respectively). No ethnic differences in the frequency of 11q23/MLL rearrangements were observed between Hispanics and non-Hispanic Whites. Among B-lineage acute lymphoblastic leukemia patients, the percentage of TEL-AML1 translocations was significantly lower in Hispanics (13%) than in non-Hispanic Whites (24%; P = 0.01). This is the first time that this ethnic variation has been observed in a large number of patients in a defined geographic region, which is consistent with findings from smaller international studies. The mechanistic basis for this 2-fold variation in frequency of TEL-AML1 may be due to ethnic-specific risk factors or genetics and should be explored further.  相似文献   
1000.
Full-term pregnancy early in life results in a permanent reduction in lifetime breast cancer risk in women. Parous rats and mice are also refractory to chemical carcinogenesis. Therefore, investigation of the differences between mammary glands from virgin and parous rats would provide valuable information regarding the protective effects of early full-term pregnancy. In this report, we examined the gene expression patterns in mammary glands from virgin and parous Lewis rats. Using differential display technology, a novel 4.2 kb cDNA, designated rat mammary tumor-1 (RMT-1) was isolated. Northern blot analysis of RMT-1 showed that RMT-1 expression was higher in the pre-pubertal and pubertal stages during rat mammary gland development while it was down-regulated in mammary glands from mature virgin and parous rats. RMT-1 expression was highest in rat mammary cancers compared with either the mammary glands of virgin or parous rats. At the Northern blot sensitivity level, RMT-1 expression was found only in the mammary gland. Northern blot analysis also showed that the expression of this gene was found in 74% of N-methyl-nitrosourea (MNU)-induced mammary cancers while it was not found in MNU-induced cancers from other organs. The examination of the RMT-1 gene structure revealed that it consists of five exons spanning 5.9 kb. Using fluorescence in situ hybridization, the gene was localized on rat chromosome 1 band q 43-51. The present data show that there is a correlation between high RMT-1 expression and rat mammary carcinogenesis or decreased RMT-1 expression and parity associated refractoriness to chemically induced mammary carcinogenesis. However, whether or not RMT-1 gene has a functional role in these processes remains to be investigated.  相似文献   
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