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81.

Objective

To compare and analyze three therapies on patients with primary central nervous system lymphoma (PCNSL), aiming to provide evidences for future treatment and prognosis.

Methods

Clinical data of 26 cases of PCNSL with normal immune system confirmed by postoperative pathology were retrospectively analyzed. Among them there were six cases with operation only, nine cases with operation and radiotherapy, and 11 cases with operation, radiotherapy and chemotherapy, and their survival rate was compared as well.

Results

The survival time of patients with operation only, operation combined with radiotherapy and operation combined with radiotherapy and chemotherapy was 6–11?months, 15–24?months and 24–51?months, respectively. And their median survival time was only nine months, 21?months and 38?months, respectively.

Conclusions

Operation combined with radiotherapy and chemotherapy can dramatically extend PCNSL patients’ survival time, therefore, it can be regarded as the first-line therapy.  相似文献   
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83.
Currently, the impact of introduced predators on small mammal population decline is a focal research direction in the Australian desert literature. In all likelihood though, single‐factor explanation of population dynamics is inadequate, leaving gaps in our knowledge of the multitude of potential influences on small mammal abundance and occupancy patterns in time and space. Here, we investigated floristic gradients across four potential refuge sites of the central rock‐rat, Zyzomys pedunculatus, a granivore rodent (50–120 g) that is endemic to central Australia and is categorised as critically endangered. The study took place in Tjoritja/West MacDonnell National Park in the MacDonnell Ranges bioregion. Floristic sampling was allocated across the four sites, the locations of which were predetermined by an established monitoring and management programme for the central rock‐rat. Our aim was to examine the relationship between environmental gradients and floristic composition across the four sites, and thereby test the extent to which the patterns of food type and food availability can inform central rock‐rat spatio‐temporal dynamics. We found high site‐scale floristic patterning that related foremost to elevation and then to antecedent rainfall and time‐since‐fire and fire‐severity effects. To interpret these results, we applied the principles of refuge theory and we described a gradient from core refuge habitat to intermittent and then marginal habitat within the current central rock‐rat stronghold area. Overall, our results implied a strong floristic basis to central rock‐rat site occurrence, and they thus compel us to take explicit account of spatial (elevation) and temporal (rainfall–productivity and fire‐disturbance) influences on the food axis of potential refuge sites of this critically endangered species.  相似文献   
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85.
姚春馨  田果廷  王晖 《菌物学报》2022,41(12):2095-2097
‘云白灵芝’3个新品种由采自云南不同地区的野生白肉灵芝菌株,经常规育种系统选育获得,属白肉灵芝Ganoderma leucocontextum。3个品种的子实体菌肉洁白、质软,弹射孢子粉少,形态特征差异大。菌丝生长适宜温度18-23 ℃,子实体发育最适温度15-23 ℃,菌丝长速快,发菌期、出菇期短,是中低温型早熟新品种。3个品种均适宜熟料袋栽覆土栽培,干芝产量和品质均高于对照品种。  相似文献   
86.
细菌在海洋生物地球化学循环中发挥着重要作用。为更好地了解海洋细菌的特征及其在海洋环境中的潜在作用, 本文利用纯培养与16S rRNA基因高通量测序技术对中印度洋与南海西部海域表层海水细菌多样性进行研究。纯培养结果表明, 自中印度洋与南海西部表层海水中共分离275株可培养海洋细菌, 隶属于4门49属75种。变形菌门是绝对优势类群(占总株数的68.7%), 其次是放线菌门(21.5%)、拟杆菌门(9.1%)和厚壁菌门(0.7%)。在属水平, 微杆菌属(Microbacterium)与弧菌属(Vibrio)是主要的优势属, 共占总株数的30.0%。在3种分离培养基中, 自1/10 × 2216E培养基中分离细菌的数目与种类最多(89株, 30属); 分离菌株中的细菌菌株有7、9与3个属分别仅在2216E、1/10 × 2216E及葡萄糖甘露糖(glucose-mannose, GM)培养基中生长。此外, 共分离培养出50株细菌(26种)可能代表潜在新分类单元。高通量测序结果显示, 中印度洋和南海西部表层海水中共有23个门531个属。优势门类为变形菌门(72.2%)和拟杆菌门(15.3%), 优势属为嗜冷杆菌属(Psychrobacter, 24.4%)、盐单胞菌属(Halomonas, 16.3%)和亚硫酸杆菌属(Sulfitobacter, 13.9%)。此外, 中印度洋表层海水细菌Shannon-Wiener指数与Pielou均匀度指数显著高于南海西部(P < 0.05), 且细菌群落结构显著不同(P < 0.05)。综合纯培养与原位细菌数据得出, 中印度洋与南海西部海洋细菌具有丰富的多样性, 具有进一步开发研究的价值。  相似文献   
87.
Neuroinflammation is considered a challenging clinical problem. Chronic inflammatory responses play important roles in the onset and progression of various neurodegenerative diseases, including multiple sclerosis (MS). Previous studies have shown that astrocytes express small heat shock protein αB-crystallin (CRYAB) which is capable of inhibiting inflammatory responses in astrocytes per se. However, the underlying mechanisms of CRYAB-induced modulation of neuroinflammation are still not fully understood. In the present study, we investigated the role of extracellular CRYAB in the interaction between microglia and astrocytes in the context of MS-associated neuroinflammation. We found that the expression of CRYAB was profoundly increased in EAE mice. CRYAB was preferentially expressed in astrocytes and could be secreted via exosomes. Levels of exosomal CRYAB secreted from astrocytes were markedly increased under stress conditions. Furthermore, incubation of immortalized astrocytes or microglia cell lines with CRYAB remarkably suppressed astrocytes and microglia-mediated inflammatory responses in both autocrine and paracrine manners. Our results reveal a novel function for extracellular CRYAB in the regulation of neuroinflammation. Targeting extracellular CRYAB-modulated neuroinflammation is a potential therapeutic intervention for MS.  相似文献   
88.
Formation of bacterial biofilms is a risk with many in situ medical devices. Biofilm-forming Bacillus species are associated with potentially life-threatening catheter-related blood stream infections in immunocompromised patients. Here, bacteria were isolated from biofilm-like structures within the lumen of central venous catheters (CVCs) from two patients admitted to cardiac hospital wards. Isolates belonged to the Bacillus cereus group, exhibited strong biofilm formation propensity, and mapped phylogenetically close to the B. cereus emetic cluster. Together, whole genome sequencing and quantitative PCR confirmed that the isolates constituted the same strain and possessed a range of genes important for and up-regulated during biofilm formation. Antimicrobial susceptibility testing demonstrated resistance to trimethoprim-sulphamethoxazole, clindamycin, penicillin and ampicillin. Inspection of the genome revealed several chromosomal β-lactamase genes and a sulphonamide resistant variant of folP. This study clearly shows that B. cereus persisting in hospital ward environments may constitute a risk factor from repeated contamination of CVCs.  相似文献   
89.
Increasing numbers of cancer patients survive and live longer than five years after therapy, but very often side effects of cancer treatment arise at same time. One of the side effects, chemotherapy-induced cognitive impairment (CICI), also called “chemobrain” or “chemofog” by patients, brings enormous challenges to cancer survivors following successful chemotherapeutic treatment. Decreased abilities of learning, memory, attention, executive function and processing speed in cancer survivors with CICI, are some of the challenges that greatly impair survivors' quality of life. The molecular mechanisms of CICI involve very complicated processes, which have been the subject of investigation over the past decades. Many mechanistic candidates have been studied including disruption of the blood-brain barrier (BBB), DNA damage, telomere shortening, oxidative stress and associated inflammatory response, gene polymorphism of neural repair, altered neurotransmission, and hormone changes. Oxidative stress is considered as a vital mechanism, since over 50% of FDA-approved anti-cancer drugs can generate reactive oxygen species (ROS) or reactive nitrogen species (RNS), which lead to neuronal death. In this review paper, we discuss these important candidate mechanisms, in particular oxidative stress and the cytokine, TNF-alpha and their potential roles in CICI.  相似文献   
90.
As the mammalian central nervous system matures, its regenerative ability decreases, leading to incomplete or non‐recovery from the neurodegenerative diseases and central nervous system insults that we are increasingly facing in our aging world population. Current neuroregenerative research is largely directed toward identifying the molecular and cellular players that underlie central nervous system repair, yet it repeatedly ignores the aging context in which many of these diseases appear. Using an optic nerve crush model in a novel biogerontology model, that is, the short‐living African turquoise killifish, the impact of aging on injury‐induced optic nerve repair was investigated. This work reveals an age‐related decline in axonal regeneration in female killifish, with different phases of the repair process being affected depending on the age. Interestingly, as in mammals, both a reduced intrinsic growth potential and a non‐supportive cellular environment seem to lie at the basis of this impairment. Overall, we introduce the killifish visual system and its age‐dependent regenerative ability as a model to identify new targets for neurorepair in non‐regenerating individuals, thereby also considering the effects of aging on neurorepair.  相似文献   
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