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1.
We present a computerized method for the semi-automatic detection of contours in ultrasound images.The novelty of our study is the introduction of a fast and efficient image function relating to parametric active contour models.This new function is a combination of the gray-level information and first-order statistical features,called standard deviation parameters.In a comprehensive study,the developed algorithm and the efficiency of segmentation were first tested for synthetic images.Tests were also performed on breast and liver ultrasound images.The proposed method was compared with the watershed approach to show its efficiency.The performance of the segmentation was estimated using the area error rate.Using the standard deviation textural feature and a 5×5 kernel,our curve evolution was able to produce results close to the minimal area error rate(namely 8.88% for breast images and 10.82% for liver images).The image resolution was evaluated using the contrast-to-gradient method.The experiments showed promising segmentation results.  相似文献   

2.
The population activities of golden monkeys (Rhinopithecus roxellana) in the Xiaoshennongjia of Badong county,Hubei Province had been surveyed by consecutively tracing and grossly counting from 0ct.2000 to June 2002.The result indicated the anmount the golden monkey that iuhabit in here about 600-800 individuals.They moved clockwise in a circular track.236 golden monkeys of 2 groups had recorded by video camera during survey in Apr.2001,among them there were 59.05% adult and 40.95% of underage,the rate was 1:0.9,the sex ratio of adult was 1:1.38 (male:female).117 individuals of three different groups were recorded in random in 2002,among them were 56.41% of adult and 43.59% underage,the rate was 1:0.67,the sex ratio of adult was 1:1.2.The young were hem from the beginning the month of March.  相似文献   

3.
扁蓄总黄酮提取方法的比较   总被引:9,自引:0,他引:9  
The factors which effected the extraction of total flavones from Polygonum aviculare L.var.aviculore were discuseed with respects to solvent,concentration and the extracting temperature.The rutin was used as a standard compound,the total flavones extracted by the different extracting procedure were quantitated by measurement of absorbance at 510 nm.The results show that 80℃ and 35% alcohol are optimal and the extracting rate of the total flavones in as high as 4.349%.  相似文献   

4.
The histological and ultra-structure of the pituitary in diploid red crucian carp(Carassius auratus red var.),triploid crucian carp and allotetraploid hybrids within and after the breeding season were comparatively studied.The result showed that there were six endocrine cell types in the pituitary of these three kinds of fishes,and there was an obvious difference in cell size among different ploidy level fishes.As for the same type of pituitary cells,the cell size was increased gradually with the in- creasing ploidy level.In the breeding season,the allotetraploid hybrids had higher proportion of go- nadotropin cells(GTH)than triploids,and the triploids had higher proportion of GTH than diploids.The results were related to the earlier sexual maturity of allotetraploid hybrids and sterility of triploid cru- cian carp.On the other hand,among the three kinds of fishes,the proportion of somatotropin(STH) cells in triploids crucian carp was the highest,whereas that in allotetraploid hybrids was the lowest. The results might be connected with the faster growth rate of triploids and slower growth rate of al- lotetraploid hybrids.In addition,in GTH cells of meso-adenohypophysis after the breeding season, there were many endocrine particles in triploids,while those endocrine particles were released from the cells in allotetraploids and diploids.This result showed that the sterility of triploid crucian carp might be related to the hormone which was not released from the GTH cells.In a word,the present study indicated that the differences in the structure of pituitary among different ploidy level fishes contributed to their difference in the growth rate and gonadal development.  相似文献   

5.
Aims Forests represent the most important component of the terrestrial biological carbon pool and play an important role in the global carbon cycle. The regional scale estimation of carbon budgets of forest ecosystems, however, have high uncertainties because of the different data sources, estimation methods and so on. Our objective was to accurately estimate the carbon storage, density and sequestration rate in forest vegetation in Jilin Province of China, in order to understand the role of the carbon sink and to better manage forest ecosystems. Methods Vegetation survey data were used to determine forest distribution, size of area and vegetation types regionally. In our study, 561 plots were investigated to build volume-biomass models; 288 plots of shrubs and herbs were harvested to calculate the biomass of understory vegetation, and samples of trees, shrubs and herbs were collected to analyze carbon content. Carbon storage, density and sequestration rate were estimated by two forest inventory data (2009 and 2014), combined with volume-biomass models, the average biomass of understory vegetation and carbon content of vegetation. Finally, the distribution patterns of carbon pools were presented using ArcGIS soft ware. Important findings Understory vegetation biomass overall was less than 3% of the tree layer biomass, varying greatly among different forest types and even among the similar types. The carbon content of trees was between 45.80% 52.97%, and that of the coniferous forests was higher than that of the broadleaf forests. The carbon content of shrub and herb layers was about 39.79% 47.25% and 40%, respectively. Therefore, the vegetation carbon conversion coefficient was 0.47 or 0.48 in Jilin Province, and the conventional use of 0.50 or 0.45 would cause deviation of ±5.26%. The vegetation carbon pool of Jilin Province was at the upper range of regional carbon pool and had higher capacity of carbon sequestration. The value in 2009 and 2014 was 471.29 Tg C and 505.76 Tg C, respectively, and the total increase was 34.47 Tg C with average annual growth of 6.89 Tg C•a1. The corresponding carbon sequestration rate was 0.92 t•hm 2•a1. The carbon density rose from 64.58 t•hm 2 in 2009 to 66.68 t•hm2 in 2014, with an average increase of 2.10 t•hm2. In addition, the carbon storage of the Quercus mongolica forests and broadleaved mixed forests, accounted for 90.34% of that of all forests. The carbon increment followed the order of young > over-mature > near mature > middle-aged > mature forests. The carbon sequestration rate of followed the order of over-mature > young > near mature > middle-aged > mature forests. Both the carbon increment and the carbon sequestration rate of mature forests were negative. Furthermore, spatially the carbon storage and density were higher in the east than in the west of Jilin province, while the carbon increment was higher in northeast and middle east than in the west. The carbon sequestration rate was higher in Tonghua and Baishan in the south, followed by Jinlin in the middle and Yanbian in the east, while Baicheng and Songyuan, etc. in west showed negative values.  相似文献   

6.
Human papillomaviruses(HPVs) cause virtually all cervical cancers, the second leading cause of death by cancer among women, as well as other anogenital cancers and a subset of head and neck cancers. Approximately half of women, who develop cervical cancer die from it. Despite the optimism that has accompanied the introduction of prophylactic vaccines to prevent some HPV infections, the relatively modest uptake of the vaccine, especially in the developing world, and the very high fraction of men and women who are already infected, means that HPV-associated disease will remain as a significant public health problem for decades. In this review, we summarize some recent findings on HPV-associated carcinogenesis, such as mi RNAs in HPV-associated cancers, implication of stem cells in the biology and therapy of HPV-positive cancers, HPV vaccines, targeted therapy of cervical cancer, and drug treatment for HPV-induced intraepithelial neoplasias.  相似文献   

7.
Copyright by Science in China Press 2005 Primary hepatocarcinoma is one of the most fre-quent digestive-tract cancers, particularly in China. The incidence and death rate of primary hepatocarci-noma in China is the highest in the world, with about 1100 thousands people dying from primary hepatocar-cinoma per year[1]. Although the chemotherapeutic agents are the main therapeutic approach for hepato- carcinoma, they are relatively ineffective and result in many toxic and side effects. Accordin…  相似文献   

8.
Epstein-Barr virus (EBV) infection has been causally associated with occurrence of many malignant neoplasms. EBV-encoded small RNAs (EBERs) have been detected from about 10% of gastric carcinoma tissue cells, suggesting that EBV infection is associated with the development of gastric carcinoma. The present study pooled the data from the papers concerning EBV-related gastric cancers and performed a meta-analysis of 22 research papers. Among these papers, a total of 5475 cases with gastric cancer were enrolled, of whom 411 cases were found EBV-positive, with the EBV-positive rate being 7.5%. Among the EBV-positive gastric cancer cases, the detection rate was 11.1% in males and 3.0% in females. Compared with EBV-negative gastric cancer, EBV-positive gastric cancer had less lymph node metastasis. Based on the histological typing, of the EBV-positive gastric cancers, the diffuse type was 8.1%, and intestinal type was 8.0%. The examined specimen types included stored paraffin blocks and fresh surgically removed specimens, their EBV positive rates were 7.9% and 6.5% respectively. In terms of geographical distribution, the detection rate of EBV-positive gastric cancer was 9.4% in America, 6.1% in Asia and 9.1% in Europe. Meta-analysis showed that EBV infection occurred only in gastric cancer tissue cells and was significantly associated with the patients’ gender, lymph node metastases, and the location where tumor tissue generated and geographical distribution (P0.05), but was not significantly associated with the patients’ histological types of tumor and the types of specimens (P0.05). These results suggested that EBV-positive gastric cancer has distinct clinicopathological features.  相似文献   

9.
Effects of entomopathogenic fungus Verticillium lecanii on biological characteristics and life table of Serangiumjaponicum, a predator of whiteflies against five different conidial concentrations (1 × 10^4, 1 × 10^5, 1 × 10^6, 1 × 10^7, and 1 × 10^8 conidia/mL) were studied under laboratory conditions. The developmental periods for all immature stages (from eggs, 1 st, 2nd, 3rd, 4th instar nymph and pupae up to emergence) among the treatments were significantly different when compared to that of control, and the longest development period was observed as treated with 1 × 10^8 spore/mL. However, no significant difference on the percent survival of all immature stages was observed among the treatments and control. Also, there were no significantly different effects of V. lecanii on mean generation time, intrinsic rate, the finite rate of increase and longevity of S. japonicum among the treatments and control.  相似文献   

10.
It is of great importance to identify new cancer genes from the data of large scale genome screenings of gene mutations in cancers. Considering the alternations of some essential functions are indispensable for oncogenesis, we define them as cancer functions and select, as their approximations, a group of detailed functions in GO (Gene Ontology) highly enriched with known cancer genes. To evaluate the efficiency of using cancer functions as features to identify cancer genes, we define, in the screened genes, the known protein kinase cancer genes as gold standard positives and the other kinase genes as gold standard negatives. The results show that cancer associated functions are more efficient in identifying cancer genes than the selection pressure feature. Furthermore, combining cancer functions with the number of non-silent mutations can generate more reliable positive predictions. Finally, with precision 0.42, we suggest a list of 46 kinase genes as candidate cancer genes which are annotated to cancer functions and carry at least 3 non-silent mutations.  相似文献   

11.
INTRODUCTION: The aim of the study was to estimate the influence of a thyroid remnants' volume, postsurgical concentration of thyroglobulin and radioiodine dose on the early treatment efficacy of well differentiated thyroid cancer. MATERIAL AND METHODS: We retrospectively analyzed 91 patients (76 females, 15 men) with well differentiated thyroid cancer. RESULTS: Histological classification revealed 68.1% (62/91) papillary thyroid cancers, 25.3% (23/91) follicular thyroid cancers, and 6.6% (6/91) oxyphilic thyroid cancers. Among the group, 74 (81.3%) patients reached the remission criteria and the remaining 17 patients (18.7%) showed biochemical and morphological evidence of metastatic disease. The remission was obtained in 100% of patients in stage I of the disease, 68.4% - in stage II, 78.6% - in stage III and 33.3% in stage IV. The total radioiodine dose used in patients with remission, did not differ from the dose used in patients without remission. We did not observe the influence of remnant's volume on treatment efficacy, however larger remants required higher dose of radioiodine to obtain the remission. Patients with remission had lower postsurgical thyroglobulin concentration than patients without remission. (22.2 vs. 103.3 ng/ml; p = 0.00025). CONCLUSIONS: Early treatment results of well differentiated thyroid cancer depend on the clinical stage, and postoperative serum thyroglobulin level measured after endogenous TSH stimulation. Early treatment results are not dependent on age, sex, histological type of thyroid cancer, the dose of radioiodine used in brackets of 60-150 mCi and additional diseases. Total thyroidectomy is equally efficient as near total.  相似文献   

12.
Detection of minimal residual disease in acute leukemia by flow cytometry.   总被引:16,自引:0,他引:16  
Patients with acute leukemia in clinical remission may still have up to 10(10) residual malignant cells (the upper limit of detection by standard morphologic techniques). Sensitive techniques to detect minimal residual disease (MRD) may allow better estimates of the leukemia burden and help the selection of appropriate therapeutic strategies. Flow cytometry and polymerase chain reaction have emerged as the most promising methods for detecting submicrospopic levels of leukemia. Flowcytometric detection of MRD is based on the identification of immunophenotypic combinations expressed on leukemic cells but not on normal hematopoietic cells. It affords the detection of one leukemic cell among 10,000 normal bone marrow cells, and can be currently applied to at least two thirds of all patients with acute leukemia. Prospective studies in large series of patients have demonstrated a strong correlation between MRD levels during clinical remission and treatment outcome. Therefore, MRD assays can be reliably used to assess early response to treatment and predict relapse. In this review, we discuss methodologic aspects and clinical results of flowcytometric detection of MRD in patients with acute leukemia.  相似文献   

13.
Triple negative breast cancer (TNBC) is associated with high pathological complete remission (pCR) rate in neoadjuvant treatment (NAT). TNBC patients who achieve pCR have superior outcome than those without pCR. A meta-analysis was done to evaluate whether integrating novel approaches into NAT can improve the pCR rate in TNBC. Medical subject heading terms (Breast Neoplasm) and key words (triple negative OR estrogen receptor (ER) negative OR HER2 negative) AND (primary systemic OR neoadjuvant OR preoperative) were used to select eligible studies. Experimental arm in each study was considered as the testing regimen, and control arm was defined as the standard regimen in this meta-analysis. A total of 11 studies with 14 paired regimens were included in the final analysis. Aggregate pCR rate was 37.3% and 44.6% in the standard and testing group, respectively. Novel approaches in the testing regimen significantly improved the pCR rate in NAT of TNBC patients compared with the standard regimen, with an odds ratio (OR) of 1.34 (95% confidence interval (CI) 1.11–1.62, P = 0.002). Considering specific regimens, we demonstrated the pCR rate to be much higher in the carboplatin-containing (OR = 1.80, 95% CI 1.39–2.32, P<0.001) or bevacizumab-containing regimens (OR = 1.36, 95% CI 1.11–1.66, P = 0.003) than in the control regimens. The addition of carboplatin in NAT had a pCR rate as high as 51.2% in TNBC patients, with an absolute pCR difference of 13.8% as compared with control regimens. No significant heterogeneity was identified among studies evaluating the addition of carboplatin or bevacizumab efficacy in NAT. This meta-analysis indicates that these novel NAT regimens have achieved a significant pCR improvement in TNBC patients, especially among patients treated with carboplatin-containing or bevacizumab-containing regimen. This can help us design appropriate trials in the adjuvant setting and guide clinical practice.  相似文献   

14.
Summary To examine the clinical efficacy and the mechanism of action of polysaccharide K (PSK), a proteinbound polysaccharide extracted from a Basidiomycetes fungus, a randomized double-blind trial was performed by administering PSK to 56 patients and a placebo to another group of 55 patients after surgical operations on their colorectal cancers. The rate of patients in remission (or disease-free) was significantly higher in the PSK group than in the placebo group; the difference between both groups was statistically significant atP <0.05 by the logrank test. The survival rate of patients was also significantly (P <0.05) higher in the PSK group than in the control group. The most significant laboratory finding was that polymorphonuclear leukocytes from PSK-treated patients showed remarkable enhancement in their activities, such as random and/or chemotactic locomotion, and phagocytic activity, when compared with those in the control group. In conclusion, PSK was useful as a maintenance therapy for patients after their curative surgical operations for colorectal cancer. The beneficial effects were probably due to the activation of leukocyte functions as one of the many biological-response-modifying (activities induced by PSK).  相似文献   

15.
Fifty-one adults with acute lymphoblastic leukaemia were entered into a trial of intense initial chemotherapy and early "prophylaxis" of the central nervous system (CNS). Initial treatment with OPAL (Oncovin (vincristine), prednisolone, adriamycin (doxorubicin), and L-asparaginase (colaspase)) followed by craniospinal or cranial irradiation and intrathecal methotrexate produced remission in 36 patients (71%). Seventeen of these patients relapsed three to 18 months after the start of remission; the remainder had been in remission for 12 to 52 months by the end of the study. The predicted median duration of complete remission was 18.5 months. None of the four patients who initially had clinical evidence of CNS disease, three of whom also had leukaemic cells identical to those found in Burkitt''s lymphoma, achieved remission. Those patients who initially had hepatomegaly or splenomegaly had a shorter remission than those without. The predicted median survival was 27 months in those who achieved complete remission, one month in those who did not, and 21 months overall. The addition of colaspase and doxorubicin to vincristine and prednisolone and the use of early CNS treatment clearly improved the remission rate among adults with acute lymphoblastic leukaemia, though the presence and length of remission was affected by the extent of disease at presentation. Burkitt-like leukaemia, which had a poor prognosis, is probably a separate disease and may benefit from a different therapeutic approach.  相似文献   

16.
摘要 目的:探讨胸腔注射糖皮质激素联合标准四联抗结疗法对结核性胸膜炎患者肺功能及临床症状的影响。方法:选取2013年1月到2020年5月期间来我院进行诊治的结核性胸膜炎患者756例,入选的患者按照随机数字表法分为对照组和实验组,各378例。对照组予以标准四联抗结疗法治疗,实验组予以胸腔注射糖皮质激素联合标准四联抗结疗法治疗。对比两组疗效、肺功能[第1s用力呼气容积占预计值百分比(FEV1%pred)、每分钟最大通气量占预计值百分比(MVV%pred)、用力肺活量占预计值百分比(FVC%pred)],记录两组胸水吸收时间、胸膜厚度、临床症状缓解时间、住院时间、并发症及胸膜肥厚粘连发生情况。结果:实验组的临床总有效率较对照组高(P<0.05)。治疗后,两组FEV1%pred、MVV%pred、FVC%pred均升高,且实验组高于对照组(P<0.05)。实验组临床症状缓解时间、胸水吸收时间、住院时间较对照组短(P<0.05),胸膜厚度大于对照组(P<0.05)。实验组的胸膜肥厚粘连、并发症总发生率低于对照组(P<0.05)。结论:胸腔注射糖皮质激素联合标准四联抗结疗法治疗结核性胸膜炎,疗效可靠,可改善患者肺功能,促进症状改善。  相似文献   

17.
BackgroundNo study has investigated the impacts of migraine on depression, anxiety, and somatic symptoms and remission at the two-year follow-up point among patients with major depressive disorder (MDD). This study aimed to investigate the above issues.MethodsPsychiatric outpatients with MDD recruited at baseline were investigated at a two-year follow-up (N = 106). The Hamilton Depression Rating Scale, Hospital Anxiety and Depression Scale, and Depression and Somatic Symptoms Scale were used. Migraine was diagnosed according to the International Classification of Headache Disorders, 2nd edition. The patients were divided into no migraine, inactive migraine, and active migraine subgroups. Multiple logistic regressions were used to investigate the significant factors related to full remission of depression.ResultsAmong patients without pharmacotherapy at the follow-up, patients with active migraine had significantly greater severities of anxiety and somatic symptoms as compared with patients without migraine; moreover, patients with active migraine had the lowest improvement percentage and full remission rate. There were no significant differences in depression, anxiety, and somatic symptoms between patients with inactive migraine and those without migraine. Active headache at follow-up was a significant factor related to a lower full remission rate.ConclusionsActive headache at follow-up was associated with a lower rate of full remission and more residual anxiety and somatic symptoms at follow-up among patients with migraine. Physicians should integrate a treatment plan for depression and migraine for the treatment of patients with MDD.  相似文献   

18.
W Hiddemann  T Büchner 《Blut》1990,60(3):163-171
The strategy for treatment of relapsed or refractory acute myeloid leukemia must primarily be based on the patient's age and clinical condition as well as on the stage of the disease. Accordingly, the general decision between an intensive approach including high-dose chemotherapy or possibly immediate allogeneic bone marrow transplantation versus less-aggressive palliative treatment will precede the selection of the most appropriate salvage regimen. In patients qualifying for intensive second-line chemotherapy the duration of the first remission and the number of relapses provide the means to discriminate between refractoriness or maintained responsiveness to conventional protocols. More than 50% of patients with first relapses after 6-12 months remission duration will respond to standard therapy again and should therefore not be entered on investigational agents with unproven antileukemic activity. The latter seems deeply warranted, on the other hand, for early relapses, second recurrences and resistant first relapses with a remission rate of less than 30% after conventional regimens. These guidelines not only provide an objective rationale for selecting the most appropriate strategy at relapse in individual patients. Furthermore, they facilitate interstudy comparisons and a better judgement of different treatment protocols.  相似文献   

19.
Summary A group of 13 patients with acute myeloid leukaemia of differing disease status were treated with continuous intravenous infusion of high-dose recombinant interleukin-2 (rIL-2). There was up-regulation of the cellular cytotoxic functions in all these patients following the rIL-2 therapy, with increase in the natural killer (NK) activity, lectin-dependent cellular cytotoxicity, induction of cytotoxicity-linked cytoplasmic serine esterase and lymphocyte activation. However, the clinical response to rIL-2 in these patients was disappointing, especially in patients treated in frank relapse. Although 1 patient treated in early second relapse achieved a third complete remission, the duration of the remission was brief and lasted only 6 months. Adverse reactions among these patients were common. Whether or not lymphokine-activated killer cells are needed to improve the response rate over rIL-2 alone in these patients deserves further investigation.  相似文献   

20.
《Endocrine practice》2020,26(11):1320-1330
Objective: Transsphenoidal surgery (TSS) is a first-line treatment for Cushing disease (CD). However, a subset of patients with CD have no visible adenoma on magnetic resonance imaging (MRI), and whether MRI results affect surgical outcomes is controversial. The aim of this study was to compare the surgical outcomes of CD patients with negative MRI findings to those of patients with positive MRI findings.Methods: The clinical features and outcomes of CD patients who underwent TSS between January 2000 and July 2019 at Peking Union Medical College Hospital were collected from medical records. The clinical, endocrinologic, histopathologic, surgical outcomes, and a minimum 12-month follow-up of 125 consecutive CD patients with negative MRI findings were compared with those of 1,031 consecutive CD patients with MRI-visible adenomas.Results: The total remission rate was 73.3% after TSS, and 11.8% of patients experienced recurrence. Of 1,031 patients with MRI-visible adenomas, postoperative remission was achieved in 762 patients (73.9%), and the recurrence of CD was observed in 94 (12.3%) patients. Of the 125 patients with negative MRI findings, postoperative remission was achieved in 85 (68%) patients, and recurrence was observed in 6 (7.1%) patients. The remission rate and recurrence rate were not significantly different between patients with negative MRI findings and those with positive MRI findings (all P>.05). The remission rate was not significantly different between patients who did or did not undergo bilateral inferior petrosal sinus sampling (BIPSS) in patients with negative MRI findings (P>.05). In the patients with negative MRI findings who underwent BIPSS, the remission rate of patients with positive BIPSS results was not different from that in patients with negative BIPSS results (P>.05). The lack of prior TSS, the detection of a tumor during operation, and pathologic confirmation of adenoma were associated with a higher surgical remission rate in patients with negative MRI findings (all P<.05). Similar results were observed in the patients with positive MRI findings (all P<.05). In addition, the major perioperative complications, including intraoperative cerebrospinal fluid leakage, hypopituitarism, and transient diabetes insipidus, were not related to the MRI results (all P>.05).Conclusion: The remission rate and recurrence rate were not different between patients with negative MRI findings and those with positive MRI findings. If CD is clearly diagnosed according to biochemical tests, radiologic examinations, and BIPSS, we recommend TSS as the first-line treatment for patients, even if the MRI results are negative.  相似文献   

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