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91.
92.
"引江济淮"工程途经地区血吸虫病流行现状调查   总被引:1,自引:1,他引:1  
目的 调查“引江济淮”工程途经地区血吸虫病流行情况,为论证该工程能否引起钉螺扩散和血吸虫病望延提供依据。方法收集“引江济淮”工程长江—巢湖段所属地区血吸虫病流行情况的基本资料,常规方法调查钉螺分布情况;用IHA法检测居民血吸虫病抗体;用孵化法检查耕牛血吸虫感染情况;调查船只钉螺携带情况。结果 工程预期设置的两个引水口地区是血吸虫病重流行区,钉螺分布广,人、畜感染重;工程途经的无为县与和县血吸虫病流行情况严重,居民感染率高,且有病牛存在;“引江济巢”工程实施后,已有钉螺向内河扩散;船只未发现携带钉螺。结论 “引江济淮”工程途经地区血吸虫病流行严重。工程实施后有可能引起钉螺扩散和血吸虫病的蔓延。  相似文献   
93.
Papillary carcinoma arising from the extrahepatic bile duct often shows superficial ductal spread. We report herein the case of a patient with extensive superficial spread of non-invasive papillary cholangiocarcinoma, which was depicted with peroral cholangioscopy. A 65-year-old woman presented with the sudden-onset of severe epigastric pain. Ultrasonography revealed acute acalculous cholecystitis. Endoscopic retrograde cholangiography found small protruding lesions around the confluence of the cystic duct, suggestive of a cholangiocarcinoma. As the contour of the middle and upper bile ducts it was slightly irregular on the cholangiogram, the presence of superficial ductal spread was suspected. Peroral cholangioscopy revealed small papillary lesions around the confluence of the cystic duct and fine granular mucosal lesions in the middle and upper bile ducts and the right hepatic duct, suggesting a superficially spreading tumor. A right hepatectomy with bile duct resection was performed and no residual tumor was found. Histological examination revealed a non-invasive papillary carcinoma arising from the cystic duct with extensive superficial spread. Our experience of this case and a review of the literature suggest that a fine granular or fine papillary appearance of the ductal mucosae on cholangioscopy indicates superficial spread of papillary cholangiocarcinoma, for which peroral cholangioscopy is an efficient diagnostic option.  相似文献   
94.
Summary Thirty-five children with newly-diagnosed Type 1 (insulin-dependent) diabetes mellitus and their 47 siblings were investigated for the presence of IgM antibodies to Coxsackie B virus serotypes 1–5 (CBV1-5) with the aid of -antibody-capture radioimmunoassays. When a high cut-off value was used, 16 (46%) diabetic children and 16 (34%) siblings showed CBV-IgM. Of the siblings of diabetic patients positive for CBV-IgM, 11 (44%) were CBV-IgM-positive; the corresponding figure for the siblings of negative patients was five (26%). With a lower cut-off value, leading to a borderline titre, the frequency of IgM positivity increased in both the patients and siblings. When the borderline titres were included, the number of IgM-positive patients was 19 (54%) and the corresponding number of siblings was 29 (62%). Of the siblings of positive patients, 27 (93 %) showed CBV-IgM, and of the siblings of the negative patients, two (11 %) were CBV-IgM-positive. Sixteen (89 %) siblings of IgM-negative patients remained negative. Regarding the serotypes of CB V to which IgM was directed, CBV 4 was most frequent, followed by serotypes CBV 3, CBV 2, CBV 5 and CBV 1. There was a striking similarity between the individual diabetic child and his or her sibling(s) concerning this specificity of IgM. It is concluded that within most families with a newly-diagnosed diabetic child positive for CBV-IgM the same serotype(s) of the virus circulates and that the intrafamilial spread of virus is considerable. The results strongly indicate that the IgM detected was CBV-specific and caused by a recent or current CBV infection. It is highly probable that the same strain of virus was present in different members of the same family. Therefore, if diabetogenic CBV strains do in fact exist, additional factors must be of importance for the development of Type 1 diabetes in children infected with such a CBV strain but remaining non-diabetic.  相似文献   
95.
Endoscopic ultrasonography in diagnosis and staging of pancreatic cancer   总被引:9,自引:0,他引:9  
The accuracy of endoscopic ultrasonography (EUS) for diagnosis of pancreatic cancers was evaluated in consecutive 232 patients with possible pancreatic cancer, and that for assessment of their locoregional spread was evaluated in 28 patients with pancreatic cancer subjected to pancreatectomy, in comparison with the accuracies of transabdominal ultrasonography (US) and computed tomography (CT). EUS was found to be significantly more accurate than US or CT and was especially useful for detecting small pancreatic cancers of less than 2 cm in diameter. With EUS, pancreatic cancers could be detected as a hypoechoic mass with a relatively unclear margin and irregular internal echoes. EUS was also more sensitive than CT and US for detecting venous and gastric invasions: it was more useful for detecting direct invasion of pancreatic cancers when the tumors were less than 3 cm in diameter. These findings indicate that EUS is an accurate method for diagnosis of pancreatic cancer and assessment of their locoregional spread and is particularly useful for detecting small tumors.  相似文献   
96.
Upward Spread of Masking in Normal and Impaired Ears

Upward spread of masking was studied for normals and sensorineurally hearing-impaired subjects with high-frequency hearing loss. Hearing-impaired listeners were recruited in such a way as to present normal hearing on the frequency of the masker, that is a narrow band of noise centered at 1 000 Hz. Levels of the masker were set at 70, 80 and 90 dB, respectively. Results first indicated the presence of a relationship between masked and elevated absolute thresholds for a masker level of 70 dB. At masker levels of 80 and 90 dB, hearing-impaired listeners showed excessive upward spread of masking in spite of normal hearing sensitivity at the masker frequency: with 80 and 90 dB of noise, upward spread of masking grew, respectively, 2.6 and 1.6 times faster than in normals. Furthermore, excessive upward spread of masking was shown to progress as a function of hearing loss. Results were interpreted as additional evidence of abnormal frequency selectivity in sensorineurally hearing-impaired listeners.  相似文献   
97.
Purpose: Surgery in frontal lobe epilepsy (FLE) has a worse prognosis regarding seizure freedom than anterior lobectomy in temporal lobe epilepsy. The current study aimed to assess whether intracranial interictal and ictal EEG findings in addition to clinical and scalp EEG data help to predict outcome in a series of patients who needed invasive recording for FLE surgery. Methods: Patients with FLE who had resective surgery after chronic intracranial EEG recording were included. Outcome predictors were compared in patients with seizure freedom (group 1) and those with recurrent seizures (group 2) at 19–24 months after surgery. Key Findings: Twenty‐five patients (16 female) were included in this study. Mean age of patients at epilepsy surgery was 32.3 ± 15.6 years (range 12–70); mean duration of epilepsy was 16.9 ± 13.4 years (range 1–48). In each outcome group, magnetic resonance imaging revealed frontal lobe lesions in three patients. Fifteen patients (60%) were seizure‐free (Engel class 1), 10 patients (40%) continued to have seizures (two were class II, three were class III, and five were class IV). Lack of seizure freedom was seen more often in patients with epilepsy surgery on the left frontal lobe (group 1, 13%; group 2, 70%; p = 0.009) and on the dominant (27%; 70%; p = 0.049) hemisphere as well as in patients without aura (29%; 80%; p = 0.036), whereas sex, age at surgery, duration of epilepsy, and presence of an MRI lesion in the frontal lobe or extrafrontal structures were not different between groups. Electroencephalographic characteristics associated with lack of seizure freedom included presence of interictal epileptiform discharges in scalp recordings (31%; 90%; p = 0.01). Detailed analysis of intracranial EEG revealed widespread (>2 cm) (13%; 70%; p = 0.01) in contrast to focal seizure onset as well as shorter latency to onset of seizure spread (5.8 ± 6.1 s; 1.5 ± 2.3 s; p = 0.016) and to ictal involvement of brain structures beyond the frontal lobe (23.5 ± 22.4 s; 5.8 ± 5.4 s; p = 0.025) in patients without seizure freedom. The distribution of ictal onset patterns was similar in both groups, and fast rhythmic activity in the beta to gamma range was found in 57% of seizure‐free patients compared to 70% of patients with recurrent seizures. Analysis of the temporal relation between first clinical alterations and EEG seizure onset did not reveal significant differences between both groups of patients. In multivariate analysis, resection in the left hemisphere (odds ratio [OR] 12.197 95% confidence interval [95% CI] 1.33–111.832; p = 0.027) and onset of seizure spread (odds ratio [OR] 0.733, 95% CI 0.549–0.978, p = 0.035) were independent predictors of ongoing seizures. Significance: Widespread epileptogenicity as indicated by rapid onset of spread of ictal activity likely explains lack of seizure freedom following frontal resective surgery. The negative prognostic effect of surgery on the left hemisphere is less clear. Future study is needed to determine if neuronal network properties in this hemisphere point to intrinsic interhemispheric differences or if neurosurgeons are restrained by proximity to eloquent cortex.  相似文献   
98.
To understand the emergence of vaccinia virus Cantagalo strain in the Amazon biome of Brazil, during 2008-2010 we conducted a molecular and epidemiologic survey of poxvirus outbreaks. Data indicate that animal movement was the major cause of virus dissemination within Rondonia State, leading to the establishment and spread of this pathogen.  相似文献   
99.
IntroductionTumor spread through air spaces (STAS) has recently been reported as a form of tumor invasion having an unfavorable prognosis, but the significance of a small amount of STAS is not known. The aim of this study was to perform a semiquantitative assessment of STAS.MethodsSmall (≤2 cm) stage I lung adenocarcinomas surgically resected at our institution between 2003 and 2009 were assessed semiquantitatively in the most prominent area as no STAS, low STAS (1–4 single cells or clusters of STAS), or high STAS (≥5 single cells or clusters of STAS) by using a 20× objective and a 10× ocular lens. A statistical analysis was performed to determine the impact of clinicopathologic parameters on STAS and to clarify the relationship between STAS and patient survival.ResultsSTAS was assessed as no STAS in 109 of 208 cases (52.4%), as low STAS in 38 cases (18.3%), and as high STAS in 61 cases (29.3%). There were statistically significant associations between higher STAS and solid predominant invasive adenocarcinoma (p < 0.001), pleural invasion (p < 0.001), lymphatic invasion (p < 0.001), vascular invasion (p < 0.001), and tumor size of 10 mm or more (p = 0.037). There was a significant association between increasing STAS and shorter recurrence-free survival (RFS) in univariate analysis (no STAS, 154.2 months; low STAS, 147.6 months; and high STAS, 115.6 months). In a multivariate Cox proportional hazards model, only STAS (p = 0.015) remained a significant predictor of RFS.ConclusionsWe found that one-third of resected small adenocarcinomas had high STAS. Higher STAS was predictive of worse RFS.  相似文献   
100.
BACKGROUND: Surgery for squamous cell carcinoma (SCC) arising or extending to the hypopharynx is generally reserved for advanced disease or salvage. The prognosis of patients requiring pharyngectomy is poor, and the perioperative morbidity is significant. The aim of the present study is to describe the disease-related and treatment-related outcomes of patients undergoing primary and salvage pharyngectomy for cancer of the hypopharynx and larynx over a 10-year period from a single institution. METHODS: We retrospectively reviewed 138 partial and circumferential pharyngectomies performed at a tertiary referral center between 1992 and 2002. There were 31 females and 107 males. The median age was 62 years (range, 27-81 years), and mean follow-up was 3.6 years. Salvage pharyngectomy for radiation failure was performed in 72 patients (52%), and in 66 patients (48%) pharyngectomy was performed as the primary treatment. RESULTS: The 5-year overall survival rate after salvage pharyngectomy was 31% and after primary pharyngectomy was 38%. The 5-year disease-specific survival (DSS) for salvage was 40% and after primary surgery was 45%. The 5-year local and regional control rates for salvage pharyngectomy were 71% and 70%, respectively, and for primary pharyngectomy were 79% and 67%, respectively. The perioperative mortality rate was 3.6%, and the combined morbidity rate was 70%. Postoperative hypocalcemia developed in 44% of patients, a pharyngocutaneous fistula developed in 31% of patients, and the long-term stricture rate was 15%. Variables adversely affecting DSS on univariate analysis were nodal metastases (p = .044), extracapsular spread (ECS) (p = .006), poorly differentiated tumors (p = .015), lymphovascular invasion (p = .042), and positive tumor margins (p = .026). ECS (p = .023) was the only independent prognostic variable on multivariable analysis; however, there was a trend toward significance for nodal metastases (p = .064) and tumor differentiation (p = .079). CONCLUSION: This study demonstrates that both salvage pharyngectomy and primary surgery for advanced disease are viable options with high locoregional control. However, this represents a high-risk group in terms of both operative morbidity and survival. Patients with nodal metastases, ECS, and poorly differentiated tumors are likely to succumb to their disease and should be selected for adjuvant therapy when possible.  相似文献   
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