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81.
In a personal survey, by structured interview, we have investigated some of the factors which led 100 healthy mothers (63 primiparae) to decide to breast-feed their healthy babies, and 100 comparable mothers (43 primiparae) to decide to bottle-feed. Past experience (either personal or that of their family and friends) was of considerable but not overriding importance, and the decisions were apparently made surprisingly early in most cases. But much more effective educational approaches are needed, perhaps starting in the schools, and concentrated in the antenatal clinic, to allow mothers to reach the right decision for themselves and their babies. The reasons for early cessation of breast-feeding were also investigated, and suggested that those mothers opting for breast-feeding need better technical information and support.  相似文献   
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Background

Hyperglycemia can impair the male reproductive system in experimental animals and in men during reproductive age. Studies have shown that vitamin C has some good effects on male reproductive system, and therefore vitamin C treatment could attenuate the dysfunctions in this system caused by hyperglycemia. Thus, the objective of this work was to evaluate whether vitamin C treatment could attenuate reproductive dysfunctions in hyperglycemic male rats.

Methods

Adult male rats were divided into 3 groups: a normoglycemic (n = 10) and two hyperglycemic (that received a single dose of streptozotocin - 40 mg/kg BW). The two last groups (n = 10 per group) were divided into: hyperglycemic control (Hy) and hyperglycemic + 150 mg of vitamin C (HyC), by gavage during 30 consecutive days. The normoglycemic and hyperglycemic control groups received the vehicle (water). The first day after the treatment, the rats were anesthetized and killed to evaluate oxidative stress biomarkers (TBARS, SOD, GSHt and GSH-Px) in the erythrocytes, body and reproductive organ weights, sperm parameters, plasma hormone levels (FSH, LH and testosterone), testicular and epididymal histo-morphometry and histopathology.

Results

Compared with the normoglycemic animals, hyperglycemic control rats showed reduced weight of the body and reproductive organ but testis weight was maintained. It was also observed reduction of testosterone and LH levels, seminiferous tubular diameter, sperm motility and sperm counts in the epididymis. In addition, there was an increase in morphological abnormalities on spermatozoa as well as in oxidative stress level. Vitamin C reduced the oxidative stress level, diminished the number of abnormal sperm, and increased testosterone and LH levels and seminiferous tubular diameter but did not show improvement of sperm motility in relation to the hyperglycemic control group. Hyperglycemia caused a rearrangement in the epididymal tissue components (stroma, ephitelium and lumen) as demonstrated by the stereological analysis results. However, this alteration was partially prevented by vitamin C treatment.

Conclusions

We conclude that vitamin C partially attenuated some male reproductive system dysfunctions in hyperglycemic rats.  相似文献   
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Idiopathic inflammatory myopathies (IIMs) comprise a group of autoimmune diseases that are characterized by symmetrical skeletal muscle weakness and muscle inflammation with no known cause. Like other autoimmune diseases, IIMs are treated with either glucocorticoids or immunosuppressive drugs. However, many patients with an IIM are frequently resistant to immunosuppressive treatments, and there is compelling evidence to indicate that not only adaptive immune but also several non-immune mechanisms play a role in the pathogenesis of these disorders. Here, we focus on some of the evidence related to pathologic mechanisms, such as the innate immune response, endoplasmic reticulum stress, non-immune consequences of MHC class I overexpression, metabolic disturbances, and hypoxia. These mechanisms may explain how IIM-related pathologic processes can continue even in the face of immunosuppressive therapies. These data indicate that therapeutic strategies in IIMs should be directed at both immune and non-immune mechanisms of muscle damage.  相似文献   
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Phylogenetic relationships among prokaryotic and eukaryotic catalases   总被引:13,自引:1,他引:12  
Seventy-four catalase protein sequences, including 29 bacterial, 8 fungal, 7 animal, and 30 plant sequences, were compiled, and 70 were used for phylogenetic reconstruction. The core of the resulting tree revealed unique, separate groups of plant and animal catalases, two groups of fungal catalases, and three groups of bacterial catalases. The only overlap of kingdoms occurred within one branch and involved fungal and bacterial large-subunit enzymes. The other fungal branch was closely linked to the group of animal enzymes. Group I bacterial catalases were more closely related to the plant enzymes and contained such diverse taxa as the Gram-positive Listeria seeligeri, Deinocococcus radiodurans, and gamma-proteobacteria. Group III bacterial sequences were more closely related to fungal and animal sequences and included enzymes from a broad range of bacteria including high- and low-GC Gram positives, proteobacteria, and a bacteroides species. Group II was composed of large-subunit catalases from diverse sources including Gram positives (low-GC Bacilli and high-GC Mycobacteria), proteobacteria, and species of the filamentous fungus Aspergillus. These data can be interpreted in terms of two gene duplication events that produced a minimum of three catalase gene family members that subsequently evolved in response to environmental demands. Horizontal gene transfer may have been responsible for the group II mixture of bacterial and fungal large-subunit catalases.   相似文献   
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We describe a fatal case of familial hemiplegic migraine. A transient respiratory arrest in this patient led to a persistent "vegetative state," culminating in death four months later. Neuropathological findings included deep microinfarcts in the basal ganglia and a remarkable sparing of brain-stem nuclei associated with the function of respiration.  相似文献   
89.
Vasospasm is one of the main causes of skin ischemic necrosis in cutaneous and musculocutaneous flap surgery, but the pathogenic mechanism is unclear. We planned to test the hypothesis derived from clinical impression that veins are more susceptible to vasospasm than arteries in flap surgery and, once established, that venous vasospasm is difficult to resolve and more detrimental than arterial vasospasm. To this end, we investigated the differences in sensitivity to vasoconstrictors and vasodilators between the human musculocutaneous perforator (MCP) artery and vein by measuring the isometric tension of arterial and venous rings suspended in organ chambers. Vascular contraction was expressed as a percentage of the tension induced by 50 mM KCl. Relaxation was expressed as a percentage of contraction induced by a submaximal concentration (3 x 10(-9) M) of endothelin-1 (ET-1). We observed that the vasoconstrictor potency of norepinephrine was significantly higher in the MCP vein than in the MCP artery. The vasoconstrictor potency of ET-1 and the thromboxane A(2) mimetic U-46619 were similar in the MCP vein and artery, but the maximal contraction induced by ET-1 and U-46619 was significantly higher in the MCP vein than in the MCP artery. On the other hand, the MCP vein was less sensitive than the MCP artery to the relaxation effect of nitroglycerin, nifedipine, and lidocaine. These differences between the human MCP artery and vein in response to vasoactive agents lend support to the clinical impression in flap surgery that veins appear to be more susceptible to vasospasm than arteries and venous vasospasm seems to be more difficult to resolve than arterial vasospasm in cutaneous and musculocutaneous flap surgery.  相似文献   
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Background  

Efficient natural transformation in Neisseria requires the presence of short DNA uptake sequences (DUSs). Doubts remain whether DUSs propagate by pure selfish molecular drive or are selected for 'safe sex' among conspecifics.  相似文献   
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