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71.
Mortality, injury and height growth of planted Picea abies (L.) Karst, were examined over a 6 yr period in eight stands at middle altitudes (430–620 m a.s.l.) in south-east Norway. There were four residual stand density treatments (shelterwoods of high, medium and low density, 25 × 25 m patch-cut) combined with three scarification treatments (unscarified, patch scarification, inverting) in a split-plot design. Mortality was very low during the experimental period, and did not differ significantly between the residual stand density treatments (mean = 11.1%). Both survival and plant height after 6 yrs were improved by inverting, while patch scarification was intermediate but not significantly different from the unscarified alternative. The patch-cutting resulted in the tallest plants, while only minor differences in height growth were found between the shelterwood treatments. The frequency of injured plants after 6 yrs was not significantly affected by the treatments (mean = 10.6%). The improved plant establishment at inverting is in agreement with previous studies on clear-cuts.  相似文献   
72.
A 2‐year‐old male American Bulldog experienced paroxysmal staggering, altered consciousness, and hyperesthesia. Magnetic resonance (MR) imaging enabled recognition of a fourth ventricular mass causing compression of the cerebellum and brainstem and obstructive hydrocephalus. The mass was uniformly T2‐hyperintense and predominantly T1‐hypointense. A fluid line was evident on the fluid‐attenuated inversion recovery images. A thin rim of contrast enhancement was noted. Histopathologic diagnosis was a cholesterol granuloma. We were unable to identify any other reports of a cholesterol granuloma residing in the fourth ventricle of a dog. This case report documents the clinical, diagnostic imaging, and histopathologic findings of a canine intracranial cholesterol granuloma. © 2012 Veterinary Radiology & Ultrasound.  相似文献   
73.
指出了《中国图书馆分类法》第5版中未设置“中医脑系病证”类目,给这部分文献的分类和检索带来困难,分析了中医脑病学的发展并对相关文献进行了调研,并根据学科依据和文献依据提出了增设“中医脑系病证”类目的建议和方法等。  相似文献   
74.
The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.  相似文献   
75.
76.
AIM:To explore the interaction and function between ZnT3 mRNA expression and zinc elemental distribution in brain slice of mouse.METHODS:Zinc distribution was determined by SRXRF and ZnT3 mRNA expression in tissue was examined by RT-PCR method.RESULTS:Zinc content in cerebral cortex and hippocampus was significantly higher than that in other positions.The highest expression of ZnT3 mRNA was observed in cerebrum,hippocampus and testis.However,the ZnT3 mRNA was not detected in heart,liver,lung,spleen,kidney,intestine,olfactory bulb and cerebellum.CONCLUSION:ZnT3 facilitates the accumulation of zinc in synaptic vesicles and may play important roles in structuring of vesicular zinc pool.  相似文献   
77.
Cholecystokinin (CCK) is one of the first discovered gastrointestinal hormones and one of the most abundant neuropeptides in the brain. CCK, as a neurotransmitter or modulator, is involved in many different biological processes. This review presents an updated overview of the anatomical distribution of CCK in brain, the changes of cerebral CCK gene expression and CCK level during brain injury, the neuroprotective effects of CCK and its underlying mechanisms.  相似文献   
78.
AIM:To examine the effect of cholecystokinin-octapeptide (CCK-8) on focal cerebral ischemia/reperfusion injury and its underlying mechanisms.METHODS:By using the suture model of focal cerebral ischemia and reperfusion, the effects of intracerebroventricular (icv) injection of CCK-8 and proglumide, nonselective CCK receptors antagonist, on the infarct size, regional cerebral blood flow (rCBF), and the levels of nitric oxide (NO), malondialdehyde (MDA) were observed in different brain regions of rats subjected to 1 h focal cerebral ischemia followed by 24 h reperfusion.RESULTS:(1) pretreatment with different doses of CCK-8 (0.3 μg,1.0 μg,2.0 μg or 4.0 μg) could attenuate the infarct size, but the statistically significant effects of CCK-8 were obtained only at the doses of 1.0 μg and 2.0 μg(P<0.05). The neuroprotective effects of CCK-8 were blocked by pretreatment with proglumide. Administration of proglumide alone could worsen the ischemia/reperfusion injury. (2) CCK-8 (1.0 μg) inhibited the increase in NO, MDA levels in the ischemic core, and also inhibited the increase in NO level in the ischemic penumbra. The rCBF in the CCK-8 group was significantly higher than the normal value at 24 h after reperfusion (P<0.05).CONCLUSIONS:These results suggest that both endogenous and exogenous CCK-8 alleviate focal cerebral ischemia/reperfusion injury. Such an action may be associated with inhibition of free radical-induced injuries and the improvement in rCBF.  相似文献   
79.
AIM: To clarify the effects of specific and non-specific cyclooxygenase-2 (COX-2) inhibitors on gastric epithelial cell proliferating and gastric healing following acid-induced damage. METHODS: Male Sprague-Dawley rats were given 1 mL of 0.6 mol/L hydrochloric acid (HCl) into the stomach. Ten minutes after the administration of the acid, the animals were given NS-398 (COX-2 inhibitor) or indomethacin. Levels of COX-1 and COX-2 in the gastric mucosa before and after HCl-administration were analyzed using western blotting and immunohistochemical staining. Proliferating cell nuclear antigen (PCNA) was detected using immunohistochemistry for epithelial cell proliferation. Gastric lesion index (LI) was assessed using planimetry. RESULTS: Expression of COX-2 was enhanced mainly in surface epithelial cells and neck cells following HCl-administration. At 24 h following acid administration, PCNA labeling index (PCNA-LI) was (22.72±4.33) % and (21.98±5.18) % in the groups treated with 40 mg/kg of NS-398 and indomethacin respectively, which was significantly lower than that in the control group [ (34.46±3.61) %, P< 0.05 ]; LI was (1.28±0.58) % and (1.16±0.56) % in the groups treated with 4 mg/kg and 40 mg/kg of NS-398, respectively, which was significantly higher than that in the control group [ (0.58±0.24) %, P< 0.05 ]. CONCLUSIONS: The present study demonstrated that cyclooxygenase-2 inhibitors delayed gastric mucosal healing by suppressing expansion of the mucosal proliferative zone. These results provide evidence that cyclooxygenase-2 plays an important role in gastric mucosal regeneration.  相似文献   
80.
WANG Xiao-song  LI Zhi-wen 《园艺学报》2003,19(12):1695-1699
Cerebral ischemia and the aftermath of reperfusion form a hypoxic/hyperoxic sequence of events that can trigger DNA damage in neurons of central nervous system. Neuronal apoptosis will happen without immediate DNA repair. APE/Ref-1 is a multifunctional protein involoved in DNA base excision repair pathway and in redox reguiation of DNA-binding activity of AP-1 family members, which may play an important role in protection of postischemic neuronal damage.  相似文献   
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