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101.
Nerve agents and some pesticides such as diisopropylfluorophosphate (DFP) cause neurotoxic manifestations that include seizures and status epilepticus (SE), which are potentially lethal and carry long-term neurological morbidity. Current antidotes for organophosphate (OP) intoxication include atropine, 2-PAM and diazepam (a benzodiazepine for treating seizures and SE). There is some evidence for partial or complete loss of diazepam anticonvulsant efficacy when given 30?min or later after exposure to an OP; this condition is known as refractory SE. Effective therapies for OP-induced SE are lacking and it is unclear why current therapies do not work. In this study, we investigated the time-dependent efficacy of diazepam in the nerve agent surrogate DFP model of OP intoxication on seizure suppression and neuroprotection in rats, following an early and late therapy. Diazepam (5?mg/kg, IM) controlled seizures when given 10?min after DFP exposure (“early”), but it was completely ineffective at 60 or 120?min (“late”) after DFP. DFP-induced neuronal injury, neuroinflammation, and neurodegeneration of principal cells and GABAergic interneurons were significantly reduced by early but not late therapy. These findings demonstrate that diazepam failed to control seizures, SE and neuronal injury when given 60?min or later after DFP exposure, confirming the benzodiazepine-refractory SE and brain damage after OP intoxication. In addition, this study indicates that degeneration of inhibitory interneurons and inflammatory glial activation are potential mechanisms underlying these morbid outcomes of OP intoxication. Therefore, novel anticonvulsant and neuroprotectant antidotes, superior to benzodiazepines, are desperately needed for controlling nerve agent-induced SE and brain injury.  相似文献   
102.
The US Fish and Wildlife Service's National Wetlands Inventory Project   总被引:1,自引:0,他引:1  
B. O. Wilen  M. K. Bates 《Plant Ecology》1995,118(1-2):153-169
In 1974, the US Fish and Wildlife Service directed its Office of Biological Services to design and conduct an inventory of the Nation's wetlands. The mandate was to develop and disseminate a technically sound, comprehensive data base concerning the characteristics and extent of the Nation's wetlands. The purpose of this data base is to foster wise use of the Nation's wetlands and to expedite decisions that may affect this important resource. To accomplish this, state-of-the-art principles and methodologies pertaining to all aspects of wetland inventory were assimilated and developed by the newly formed project. By 1979, when the National Wetlands Inventory (NWI) Project became operational, it was clear that two very different kinds of information were needed. First, detailed wetland maps were needed for site-specific decisions. Second, national statistics developed through statistical sampling on the current status and trends of wetlands were needed in order to provide information to support the development or alteration of Federal programs and policies. The NWI has produced wetland maps (scale=1:24 000) for 74% of the conterminous United States. It has also produced wetland maps (scale=1:63 360) for 24% of Alaska. Nearly 9000 of these wetland maps, representing 16.7% of the continental United States, have been computerized (digitized). In addition to maps, the NWI has produced other valuable wetland products. These include a statistically-based report on the status and trends of wetlands that details gains and losses in United States wetlands that have occurred from the mid-1970's to the mid-1980's. Other wetland products include a list of wetland (hydric) soils, a national list of wetland plant species, wetland reports for certain individual States such as New Jersey and Florida, and a wetland values data base.  相似文献   
103.
目的:探讨实验性癫痫持续状态(SE)对大鼠认知功能的影响及N-甲基-D-门冬氨酸(NMDA)受体表达的变化。方法:戊四氮诱导大鼠SE,采用抬高迷宫和Morris水迷宫观察大鼠情感反应和学习记忆功能的改变。RT-PCR方法检测大鼠海马NMDA受体亚单位NR1mRNA的表达。结果:sE组大鼠在抬高迷宫开放臂中逃避时间延长(P〈0.01),进入次数增多(P〈0、01);水迷宫中逃避潜伏期延长(P〈0.01),搜寻策略变差(P〈0.05),平台象限游泳时间百分比降低(P〈0.01),穿越平台次数减少(P〈0.01)。同时伴有海马NR1mRNA表达下调(P〈0.01)。结论:SE可使大鼠情感行为改变和学习记忆功能受损,NR1可能参与这一变化的病理生理过程。  相似文献   
104.
105.
黄羊生物学研究现状   总被引:2,自引:0,他引:2  
黄羊属偶蹄目牛科原羚属,是内蒙古草原上经济价值高,数量大的一种特有蹄动物,对黄羊的生物学研究主要涉及到分,形态学描述,分布,种群数量变化,食性,活动规律,繁殖,种群结构及动态和保护等方面。  相似文献   
106.
Convulsive status epilepticus (CSE) is a neurological disease with contraction and extension of limbs, leading to damage of hippocampus and cognition. This study aimed to explore the effects of dexmedetomidine (DEX) on the cognitive function and neuroinflammation in CSE rats. All rats were divided into control group, CSE group and DEX group. Morris water maze test was used to measure cognitive function. Acute hippocampal slices were made to detect long-term potentiation (LTP). Immunohistochemistry was used to determine the expression of α7-nicotinic acetylcholine receptor (α7-nAChR) and interleukin-1β (IL-1β). Enzyme-linked immunosorbent assay (ELISA) was used to measure serum levels of IL-1β, tumor necrosis factor-α (TNF-α), S-100β and brain-derived neurotrophic factor (BDNF). Our results showed that DEX improved the memory damage caused by CSE. DEX reduced seizure severity and increased the amplitudes and sustainable time of LTP, and also inhibited the hippocampal expression of α7-nAChR and IL-1β in CSE rats. DEX treatment decreased serum IL-1β, TNF-α and S-100β levels and increased BDNF levels. The effects of DEX on seizure severity and LTP could be simulated by nicotine or attenuated by concurrent α-bungarotoxin (α-BGT) treatment. In conclusions, DEX significantly improved spatial cognitive dysfunction, reduced seizure severity and increased LTP in CSE rats. Improvements by DEX were closely related to enhancement of cholinergic anti-inflammatory pathway.  相似文献   
107.
Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease with variable extent of remyelination coupled with the differentiation of oligodendrocytes, in which Tubulin Polymerization Promoting Protein/p25 (TPPP/p25) plays a crucial role. Previously we reported that the loss of TPPP/p25-positive oligodendrocytes in demyelinated lesions in the brain of MS patients could be a biomarker for MS [2]. In this work we tested the occurrence of TPPP/p25 in the cerebrospinal fluid (CSF) of MS patients, and by elaborating a sensitive assay for quantification of TPPP/p25 we showed that its level is significantly higher than in the case of non-MS patients. Patients with MS were diagnosed at the Department of Neurology, University of Szeged according to the clinical and laboratory diagnostic criteria of McDonald. In non-MS patients no significant pathological changes were detected on magnetic resonance imaging scans, while in MS patients multiple hyperintense T2 lesions in the white matter were detected. Kurtzke Expanded Disability Status Scale scores as well as IgG level and oligoclonal bands of MS patients were demonstrated. The sensitive assay elaborated in this study is based upon Western blot followed by chemiluminescent detection validated by human recombinant protein. The median TPPP/p25 contents in the CSF were 62.8 and 64.7 μg/L for patients with clinically isolated syndromes and relapsing remitting MS, respectively, while this value for non-MS patients was 27.9 μg/L. The enrichment of TPPP/p25 was independent of age, gender and the time period between lumbar puncture and relapse/shub. These data suggest that the TPPP/p25-based assay could be a powerful diagnostic test for MS patients.  相似文献   
108.
上海辰山植物园于2005年开始筹建,与此同时启动了的植物收集工作。本文就辰山植物园基本情况、植物收集中长远规划、进展及技术策略进行了论述。活植物收集和标本收集是辰山植物园植物收集工作的两个方面。活植物收集包括以华东植物区系植物为主的物种收集和以上海适生的观赏植物为主的园艺品种收集,如鸢尾属、绣球属、荚蒾属、锦带属和绣线菊属的观赏园艺品种。截止到2010年,辰山植物园共收集了9000种和园艺品种。其中,华东植物区系物种有1700种,来自世界范围专业苗圃的园艺品种有2800个,另有4500种和品种是种植于温室的热带和亚热带植物。目前共收集了近10000份标本,多数为研究和活植物收集的凭证标本,全部存放于上海辰山植物园标本馆(CSH)。  相似文献   
109.

Background

Although serum alkaline phosphatase (ALP) levels have been associated with hypertension, and ALP is known as an enzyme affected by alcohol consumption, no study has been published on the associations between ALP and the risk of hypertension in relation to drinking status.

Methods

We conducted a cross-sectional study of 2,681 participants (837 men and 1,846 women) aged 30 to 89 years undergoing a general health check-up to investigate the associations between ALP and hypertension in relation to drinking status.

Results

Of the 2,681 participants, 1,549 (514 men and 1,035 women) were diagnosed with hypertension. A sex difference was observed for the relationship between ALP and hypertension. While no significant association was observed for men, the association was significantly positive for women. The multivariable adjusted odds ratio and 95% coincidence interval (CI) of hypertension per increment of 1-log ALP were 0.95 (95% CI: 0.56 to 1.59) for men and 1.57 (95% CI: 1.07 to 2.33) for women. When this analysis was restricted to nondrinkers, a significantly elevated risk of hypertension was observed for men and remained significant for women; that is, 3.32 (95% CI: 1.38 to 8.02) for men and 1.68 (95% CI: 1.11 to 2.55) for women.

Conclusion

ALP is associated with hypertension for both male and female nondrinkers, but not for drinkers. For analyses of associations between ALP and blood pressure, alcohol consumption should thus be considered a potential confounder.  相似文献   
110.
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