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71.
The incidence of cerebral venous and sinus thrombosis (CVST) is still unknown. Several assumptions of the incidence have been made. In the one and only series of consecutive brain autopsies series by Towbin in1973 CVST was found in 10,9 % of patients aged 60 years or more. These findings suggest that the true incidence of CVST is higher than generally thought, but there are no other reports supporting these findings. Therefore in order to determine the incidence of latent CVST we conducted a new prospective post mortem study. All brain autopsies performed in our hospital between 1996 and 1998 on patients 60 years of age or older were examined for the presence of CVST in a prospective way. We examined the sagittal sinus, the torcula, the straight sinus, both transverse sinuses, and both sigmoideal sinuses for the presence of thrombosis. The clinical condition, medication, brain-imaging results, clinical cause of death, general findings from the body autopsy and definite cause of death were recorded. Additionally we requested the annual mortality figures of CVST at the department of the National Agency for Statistics of the Netherlands (CBS). A consecutive and prospective series of 102 brain autopsies was performed in our general hospital during a period of two years. We found one case of latent CVST in our series of 102 patients. Comparison with the findings of Towbin using a chi-square test yielded a significant difference in the incidence of latent CVST (χ2 = 7.65, p < 0.01) between the two studies. The present autopsy study demonstrates that latent CVST is rare. Received: 7 June 2002, Received in revised form: 14 October 2002, Accepted: 21 October 2002 Correspondence to H. P. Bienfait, MD  相似文献   
72.
Brain metastases   总被引:4,自引:0,他引:4  
Opinion statement Metastatic tumors to the brain are an increasing cause of morbidity and mortality in patients with systemic cancers. Many new therapies used to treat systemic cancers do not penetrate the central nervous system (CNS) and do not protect patients from the development of brain metastases. Surgery, radiosurgery, and radiation therapy are all used to treat brain metastases. It is in our opinion a mistake to use only one or two of these modalities to the exclusion of other(s). The role of systemic chemotherapy is still limited, due to both the issues of drug delivery caused by the blood brain barrier and to the relative resistance of many of these tumors to chemotherapy. Traditionally, brain metastases have been grouped together regardless of the origin of the tumor and have been treated with a single algorithm. As we encounter more patients for whom treatment of the brain metastases is an important determinant of survival, we must tailor our treatment strategies to individual tumor types. Also, we must recognize differences in each tumor’s sensitivity to chemotherapy and radiotherapy and differences in their biology.  相似文献   
73.
The C-terminal profile and ultrastructure of small and presumably early capillary amyloid β protein (Aβ) deposits were investigated in four patients with hereditary cerebral hemorrhage with amyloidosis, Dutch type. The C terminus of the 40 (Aβ40) or the 42 (Aβ42) amino acid form of Aβ was gold labeled in serial, ultrathin sections on glass slides for reflection contrast microscopy and on grids for electron microscopy. In all studied subjects, reflection contrast microscopy revealed capillaries with focal Aβ42 immunolabeling in the absence of Aβ40 labeling. In the adjacent electron microscopic section, Aβ42 labeling was confined to the capillary basement membrane. The majority of Aβ42+40 deposits showed no amyloid fibrils. Aβ42+40 deposits were sometimes observed in an unremarkable basement membrane but usually showed increased electron density and reticular structures. A small subset of Aβ42+40 deposits with basement membrane changes showed few amyloid fibrils. Aβ42+40+ capillary deposits always showed definite fibrils and were larger than Aβ42+40 capillary deposits. The present findings suggest that in capillaries the accumulation and subsequent polymerization of Aβ42, possibly in conjunction with basement membrane changes, precedes the definite fibril formation with Aβ40. Received: 9 June 1999 / Accepted: 9 September 1999  相似文献   
74.
The availability of hematopoietic growth factors has allowed a range of feasibility and uncontrolled studies with high-dose chemotherapy (with or without stem-cell support) to take place. Preliminary data from some randomized studies are now available as well. Dose-intensive chemotherapy appears to be effective in downstaging the tumor. Only a minority of patients achieve a pathologic complete remission and additional therapeutic options to control minimal residual disease are urgently needed. There are few indications that highdose chemotherapy is superior to conventional dose therapy in terms of relapse-free or overall survival. Although the results of most randomized studies are premature or unknown at this time, a modest but clinically significant survival advantage may still emerge.  相似文献   
75.

Purpose

To explore the potential complementary value of PET/CT and dynamic contrast-enhanced MRI in predicting pathological response to neoadjuvant chemotherapy (NAC) of breast cancer and the dependency on breast cancer subtype.

Methods

We performed 18F-FDG PET/CT and MRI examinations before and during NAC. The imaging features evaluated on both examinations included baseline and changes in 18F-FDG maximum standardized uptake value (SUVmax) on PET/CT, and tumour morphology and contrast uptake kinetics on MRI. The outcome measure was a (near) pathological complete response ((near-)pCR) after surgery. Receiver operating characteristic curves with area under the curve (AUC) were used to evaluate the relationships between patient, tumour and imaging characteristics and tumour responses.

Results

Of 93 patients, 43 achieved a (near-)pCR. The responses varied among the different breast cancer subtypes. On univariate analysis the following variables were significantly associated with (near-)pCR: age (p?=?0.033), breast cancer subtype (p?<?0.001), relative change in SUVmax on PET/CT (p?<?0.001) and relative change in largest tumour diameter on MRI (p?<?0.001). The AUC for the relative reduction in SUVmax on PET/CT was 0.78 (95 % CI 0.68–0.88), and for the relative reduction in tumour diameter at late enhancement on MRI was 0.79 (95 % CI 0.70–0.89). The AUC increased to 0.90 (95 % CI 0.83–0.96) in the final multivariate model with PET/CT, MRI and breast cancer subtype combined (p?=?0.012).

Conclusion

PET/CT and MRI showed comparable value for monitoring response during NAC. Combined use of PET/CT and MRI had complementary potential. Research with more patients is required to further elucidate the dependency on breast cancer subtype.  相似文献   
76.
Computerized adaptive tests (CATs) for positive and negative psychotic experiences were developed and tested in N = 5705 help‐seeking, non‐psychotic young individuals. Instead of presenting all items, CATs choose a varying number of different items during test administration depending on respondents' previous answers, reducing the average number of items while still obtaining accurate person estimates. We assessed the appropriateness of two‐parameter logistic models to positive and negative symptoms of the Prodromal Questionnaire (PQ), computed measurement precision of all items and resulting adaptive tests along psychotic dimensions by Real Data Simulations (RDS), and computed indices for criterion and predictive validities of the CATs. For all items, mean absolute differences between observed and expected response probabilities were smaller than 0.02. CAT‐POS predicted transition to psychosis and duration of hospitalization in individuals at‐risk for psychosis, and CAT‐NEG was suggestively related to later functioning. Regarding psychosis risk classifications of help‐seeking individuals, CAT‐POS performed less than the PQ‐16. Adaptive testing based on self‐reported positive and negative symptoms in individuals at‐risk for psychosis is a feasible method to select patients for further risk classification. These promising findings need to be replicated prospectively in a non‐selective sample that also includes non‐at‐risk individuals. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
77.
Various secondary microvascular degenerative and inflammatory alterations may complicate cerebral amyloid angiopathy (CAA) and contribute to the morbidity of CAA-associated stroke. We have investigated the severity of CAA-associated microangiopathy in a genetically determined Dutch form of CAA (HCHWA-D) that has major similarities to the type of CAA that more commonly occurs with aging or Alzheimer’s disease (AD). The presence and extent of the following vascular abnormalities was assessed: (1) hyalinization/fibrosis, (2) microaneurysm formation, (3) chronic (especially lymphocytic) inflammation, (4) perivascular multinucleated giant cells/granulomatous angiitis, (5) macrophages/histiocytes within the vessel wall, (6) vessel wall calcification, (7) fibrinoid necrosis, and (8) mural or occlusive thrombi. (Of these, calcification of CAA-affected vessel walls has, to our knowledge, been described in only a single patient with CAA-associated cerebral hemorrhage.) Some of the changes, such as histiocytes in blood vessel walls and the relationship of vascular hyalinosis to amyloid β/A4 protein deposition, were highlighted by immunohistochemistry. By assessing the numbers of sections in which the changes were present for each case, a ‘score’ reflective of CAA-associated angiopathy could be obtained. This ‘score’ was reproducible among several observers. We suggest that it might also be applicable to quantifying severe CAA and related microvascular degenerative changes in patients with AD. β/A4 immunoreactivity was often sparse and adventitial (or almost absent) in severely hyalinized arterioles and microaneurysms. However, macrophages were prominent in the walls of such vessels and may play a role in the pathogenesis and progression of CAA-related microvasculopathy. Received: 18 June 1997 / Revised, accepted: 22 September 1997  相似文献   
78.
Sickness absence during pregnancy has increased in Sweden as well as in other countries. STUDY OBJECTIVE--The study aimed to describe pregnancy related sickness absence and its increase from 1985-87; to consider if the increase were parallel to an increase in sickness absence for all diagnoses or could be explained by a higher birth rate; and to compare different ways of presenting sickness absence data. DESIGN--The data from a prospective incidence study of all new sick leave spells exceeding seven days in 1985-87 were related to the population at risk through relevant data from different registers. SETTING--The county of Ostergötland, Sweden (about 400,000 inhabitants). PARTICIPANTS--Subjects were approximately 70,000 sick leave-insured women aged 16-44 years, of whom some 15,000 had sickness absences > seven days. Some 4600 women gave birth in 1985, approximately 1300 of whom were listed as having pregnancy related diagnoses. MAIN RESULTS--The number of women with sick leave associated with pregnancy related diagnoses increased by 24% (95% confidence interval (CI) 15, 33%) during the period. This diagnosis group was one of the very few with an increasing number of people listed as sick. The corresponding increase for all diagnoses in women aged 16-44 years was < 1% (95% CI 1, 3%). The increase in the number of women who gave birth was 9% (95% CI 5, 13%). The sick leave rate associated with pregnancy related disorders increased by 14% (95% CI 7, 21%) in 1985-87, while that in all women aged 16-44 years increased by 3% (95% 1, 5%). (p < 0.0001). The number of sick leave days associated with pregnancy related disorders increased by 49% (p < 0.0001) in the period--twice the equivalent increase (p < 0.0001) in the total number of sick leave days for all diagnoses taken together. The sick leave rate and duration, like the increase in these variables, varied with age. Different ways of presenting the length of absence proved complementary to each other. CONCLUSIONS--After correcting for changes in the overall sick leave rate and in the birth rate, there is still an 11% increase in the sick leave rate associated with pregnancy related disorders that needs to be explained. Medical factors cannot explain this increase but changes in attitudes and practice in relation to sickness insurance among pregnant women and their doctors merit further study.  相似文献   
79.
Burkitt''s lymphoma (BL) is a highly aggressive form of B-cell non-Hodgkin''s lymphoma. The clinical outcome in children with BL has improved over the last years but the prognosis for adults is still poor, highlighting the need for novel treatment strategies. Here, we report that the combinational treatment with the Smac mimetic BV6 and TRAIL triggers necroptosis in BL when caspases are blocked by zVAD.fmk (TBZ treatment). The sensitivity of BL cells to TBZ correlates with MLKL expression. We demonstrate that necroptotic signaling critically depends on MLKL, since siRNA-induced knockdown and CRISPR/Cas9-mediated knockout of MLKL profoundly protect BL cells from TBZ-induced necroptosis. Conversely, MLKL overexpression in cell lines expressing low levels of MLKL leads to necroptosis induction, which can be rescued by pharmacological inhibitors, highlighting the important role of MLKL for necroptosis execution. Importantly, the methylation status analysis of the MLKL promoter reveals a correlation between methylation and MLKL expression. Thus, MLKL is epigenetically regulated in BL and might serve as a prognostic marker for treatment success of necroptosis-based therapies. These findings have crucial implications for the development of new treatment options for BL.  相似文献   
80.
PURPOSE: Determine whether standard or high-dose chemotherapy leads to changes in fatigue, hemoglobin (Hb), mental health, muscle and joint pain, and menopausal status from pre- to post-treatment and to evaluate whether fatigue is associated with these factors in disease-free breast cancer patients. PATIENTS AND METHODS: Eight hundred eighty-five patients were randomly assigned between two chemotherapy regimens both followed by radiotherapy and tamoxifen. Fatigue was assessed using vitality scale (score < or = 46 defined as fatigue), poor mental health using mental health scale (score < or = 56 defined as poor mental health) both of Short-Form 36, muscle and joint pain with Rotterdam Symptom Checklist, and Hb levels were assessed before and 1, 2, and 3 years after chemotherapy. RESULTS: Fatigue was reported in 20% of 430 assessable patients (202 standard-dose, 228 high-dose) with at least a 3-year follow-up, without change over time or difference between treatment arms. Mean Hb levels were lower following high-dose chemotherapy. Only 5% of patients experienced fatigue and anemia. Mental health score was the strongest fatigue predictor at all assessment moments. Menopausal status had no effect on fatigue. Linear mixed effect models showed that the higher the Hb level (P = .0006) and mental health score (P < .0001), the less fatigue was experienced. Joint (P < .0001) and muscle pain (P = .0283) were associated with more fatigue. CONCLUSION: In 3 years after treatment, no significant differences in fatigue were found between standard and high-dose chemotherapy. Fatigue did not change over time. The strongest fatigue predictor was poor mental health.  相似文献   
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