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“They did not fear much for their camels, which have their own defenses: deep-set, hirsute ears and long eyelashes that protect against flying grit, collapsible nostrils that add moisture to the searing air they breathe, and eyes with lids so thin that they can close them during a sandstorm and still see. They do not worry about them overheating, for camels have unique abilities to absorb heat in their bodies while their brains remain insulated and stable. They conserve their body water by not sweating or panting, instead retaining the heat during the day and releasing it later. On bitterly cold nights, their owners often took refuge in their warmth. As all good cameleers knew, these prized beasts were as impervious to the abuse of the desert as was possible to do, and they were as long lived as they were ornery, some reaching half a century in age. Many would outlive their masters.” (

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In the early 1990s, researchers found the first so called alcoholism gene. It was called VRD2 but its role in alcoholism has remained extremely controversial. Recently, a report suggested that genes may control the dependency on alcohol directly. Investigators at the University of California in San Francisco have discovered a gene called slo-1. The gene ordinarily codes for a protein called BK channel, found in nerve muscle and gland cells. This channel is a control for the flow of potassium ions. Alcohol makes the channel open more frequently and thus allows more ions to pour out and slows neuronal activity. The investigators suggest that slo-1 may determine sensitivity to alcohol as well to provide a mechanism for intoxication. (

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Vitreous haemorrhage occurring in association with subarachnoid haemorrhage is known as Terson’s syndrome. Recently, investigators from Belfast reviewed articles related to subarachnoid haemorrhage published from 1996 until 2003; 154 papers were reviewed. Of 181 patients with subarachnoid haemorrhage assessed prospectively 13% had vitreous haemorrhage. Of 1086 who were reviewed retrospectively, 3% had documented vitreous haemorrhage. In both series, patients with vitreous haemorrhage and subarachnoid haemorrhage had a much poorer prognostic outcome than patients with subarachnoid haemorrhage alone. The fact that prospective studies showed a higher frequency of Terson’s syndrome than retrospective studies suggests that vitreous haemorrhage is not well documented in this clinical setting. Because of its poor prognostic outcome these cases should be carefully documented. (

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Recent reports have emphasised that even relatively mild physical activity for as short as 15 minutes may help to prevent obesity. This somewhat pollyanna view about exercise has recently been challenged. In simulating the efficacy of a population-wide campaign 50% of eligible athletes would have to perform athletic walking for almost 30 minutes every day in order to meet the goal of expending an extra 420 kJ a day across the population. The authors of this study suggest this is not a realistic expectation for any population. There may be no free lunch in the obesity battle. (

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Many elderly patients run the risk of multiple small strokes particularly if they have one of the risk factors for cerebral vascular disease, especially hypertension. Ironically, a mild stroke may alter the brain in such a way that it serves to protect it from future attacks. Researchers at the National Institute of Neurologic Disorders and Stroke found that mice that had transient ischaemic attacks caused by one of the cerebral arteries being blocked for 15 minutes experienced a 70% decrease in brain damage during a second larger attack compared with a control mouse. The authors suggest that a preconditioned mouse experiences altered expression of certain genes in anticipation of a future larger stroke. (

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That magnetic resonance image (MRI) scans are of diagnostic importance in a broad range of clinical situations cannot be denied. That they are therapeutic has not previously been suggested. However, researchers from the McLean Psychiatric Hospital in Belmont, MA, have reported that MRI scans may be effective in relieving symptoms of bipolar disturbances. Of 30 bipolar patients who underwent MRI scans 23 reported immediate mood improvement. Scans did not affect healthy individuals. The McLean group does not know why MRI scans exert an antidepressant effect, but researchers note that the electrical field 1 kHz pulse rate matches the natural firing rate of brain cells. (

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Anisometropia is an important cause of amblyopia. In a study from Singapore investigators have reported that the prevalence rate of anisometropia of 1.5 dioptres was 1.57% and 2 dioptres or more was 1.01%. The prevalence rate of anisometropia of at least 2 dioptres in children with at least one myopic eye was 2.4%, whereas in those without myopia it was only 0.2%. Thus, anisometropia appears to have a high prevalence rate in a childhood population with a relatively high prevalence of myopia. The anisometropia was axial in nature suggesting that differential rate of elongation even in non-myopic subjects results in anisometropia. (

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In Germany and France, ginkgo biloba extract is one of the most commonly prescribed drugs especially used for the treatment of peripheral vascular diseases such as intermittent claudication and cerebral insufficiency. It has been reported to prevent ischaemic induced oxidation, improve cerebral blood flow, and antagonise the action of platelet activating factor. Gingko biloba extract is a standardised mixture of active substances including 24% flavonoid glycosides and 6% terpenoids obtained from green leaves of the gingko biloba tree. It is capable of scavenging free radicals such as nitric oxide and modulating intracellular signal transduction events. Investigators from Japan have reported that in rats with unilateral chronic moderately elevated intraocular pressure gingko biloba extract provided a neuroprotective effect on retinal ganglion cells. This was true even without reducing the intraocular pressure. (

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A recent study demonstrating that bone marrow stem cells injected into damaged hearts of living mice differentiated into cardiomyocytes and improved heart function was met with enormous enthusiasm among cardiovascular researchers. Now data from two independent laboratories raised questions about whether the early mouse study is correct. These studies used highly sensitive labelling methods to monitor the fate of bone marrow cells and found no evidence that these donor cells differentiated into cardiomyocytes. The studies did not address the therapeutic potential of the procedure but the potential for bone marrow stem cells to differentiate into mature cardiomyocytes has yet to be conclusively demonstrated. (

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