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61.
Using mechanical and chemical dissection methods, fibrous sheath was isolated both from normal ejaculated human spermatozoa and from rabbit cauda epididymal spermatozoa. The same techniques did not produce a pure preparation of fibrous sheath from ejaculated rabbit spermatozoa, suggesting that further cross-linking and stabilization of sperm structures occurs in response to components of the seminal plasma. The isolation procedures were monitored by phase contrast microscopy and the purity of the fibrous sheath was verified by electron microscopy. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of isolated human fibrous sheath revealed at least 14 protein bands of which the most intensely stained were of molecular weight 84, 72, 66.2, 57, 32 and 28.5 kDa. The rabbit fibrous sheath revealed at least 10 protein bands, of which the most intensely stained were 35.2, 32.7 and 28.5 kDa. The amino acid composition of the purified fibrous sheath from human and rabbit spermatozoa was similar, being high in aspartic acid and/or asparagine and glutamic acid and/or glutamine, serine, alanine, leucine, lysine and glycine, but low in histidine, tyrosine and isoleucine. This composition is similar to that reported for the rat and suggests that mammalian sperm tail fibrous sheaths are composed of similar types of proteins, although there are apparent differences in protein components between species.   相似文献   
62.
This study investigated the executive control ability of male students with Internet addiction disorder (IAD) by recording event-related brain potentials (ERP) during a color-word Stroop task. Seventeen IAD and 17 male normal university students participated. Behavior results showed that IAD students were associated with longer reaction time and more response errors in incongruent conditions than the control group. ERP results revealed that participants with IAD showed reduced medial frontal negativity (MFN) deflection in incongruent conditions than the control group. Both of the behavioral performance and ERP results indicate that people with IAD show impaired executive control ability than the normal group.  相似文献   
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64.

Background  

The tumour supressor gene TP53 is thought to be involved in neural apoptosis. The polymorphism at codon 72 in TP53 and the long form variants of the upstream variable number of tandem repeats (uVNTR) polymorphism in the dopamine D4 receptor (DRD4) gene are reported to confer susceptibility to schizophrenia.  相似文献   
65.
The impact of family and personal caregivers on inpatients with fall-related injuries in a Taiwanese medical center is investigated in this study. Taiwan has a prevalent custom for families to accompany their hospitalized loved ones during hospital stays. During the 95-day data collection period, 228 falls occurred. Results showed that if no family members were present when a patient fell, the fall-related injury was less serious. Nurses in Taiwan tend to depend on family members to help provide patient care. Regardless of whether an inpatient has a family member present, frequent bedside nursing visits are important to prevent falls.  相似文献   
66.
Chromodomain, helicase, DNA binding 5 (CHD5) is a member of a subclass of the chromatin remodeling Swi/Snf proteins and has recently been proposed as a tumor suppressor in a diverse range of human cancers. We analyzed all 41 coding exons of CHD5 for somatic mutations in 123 primary ovarian cancers as well as 60 primary breast cancers using high-resolution melt analysis. We also examined methylation of the CHD5 promoter in 48 ovarian cancer samples by methylation-specific single-stranded conformation polymorphism and bisulfite sequencing. In contrast to previous studies, no mutations were identified in the breast cancers, but somatic heterozygous missense mutations were identified in 3 of 123 ovarian cancers. We identified promoter methylation in 3 of 45 samples with normal CHD5 and in 2 of 3 samples with CHD5 mutation, suggesting these tumors may have biallelic inactivation of CHD5. Hemizygous copy number loss at CHD5 occurred in 6 of 85 samples as assessed by single nucleotide polymorphism array. Tumors with CHD5 mutation or methylation were more likely to have mutation of KRAS or BRAF (P = .04). The aggregate frequency of CHD5 haploinsufficiency or inactivation is 16.2% in ovarian cancer. Thus, CHD5 may play a role as a tumor suppressor gene in ovarian cancer; however, it is likely that there is another target of the frequent copy number neutral loss of heterozygosity observed at 1p36.  相似文献   
67.
Wang JJ  Tzeng JI  Ho ST  Chen JY  Chu CC  So EC 《Anesthesia and analgesia》2002,94(3):749-53; table of contents
Tropisetron is a 5-hydroxytryptamine subtype 3 receptor antagonist that is primarily used in the prevention of chemotherapy-induced nausea and vomiting. We evaluated the prophylactic effect of tropisetron on postoperative nausea and vomiting associated with epidural morphine. Dexamethasone and saline served as controls. One-hundred twenty women (n = 40 in each of three groups) undergoing abdominal total hysterectomy under epidural anesthesia were enrolled in this randomized, double-blinded, and placebo-controlled study. At the end of surgery, Group 1 received IV tropisetron 5 mg, whereas Groups 2 and 3 received dexamethasone 5 mg and saline, respectively. We found that tropisetron did not significantly reduce the occurrence of nausea and vomiting associated with epidural morphine. Dexamethasone, however, reduced the total incidence of nausea and vomiting from 59% to 21% (P < 0.01) and the percentage of patients requiring rescue antiemetic from 38% to 13% (P < 0.05). We conclude that IV tropisetron 5 mg did not prevent the occurrence of postoperative nausea and vomiting associated with epidural morphine. IV dexamethasone 5 mg was effective for this purpose. IMPLICATIONS: We compared the prophylactic IV administration of tropisetron 5 mg to prevent postoperative nausea and vomiting (PONV) associated with epidural morphine with dexamethasone 5 mg and saline in women undergoing hysterectomy. We found that tropisetron 5 mg did not significantly reduce the occurrence of PONV associated with epidural morphine. Dexamethasone 5 mg was effective for this purpose.  相似文献   
68.
Vascular gene therapy: a reality of the 21st century   总被引:8,自引:0,他引:8  
Current therapies for the treatment of atherosclerotic vascular disease are aimed at either disrupting or bypassing flow-limiting lesions. Preventative strategies are necessary to decrease the burden of disease but are limited by genetic predispositions to certain diseases and the body's innate response to injury. Gene therapy, defined as the purposeful therapeutic overexpression or attenuation of a gene product, has enormous potential benefits in vascular disease prevention and treatment strategies. This article reviews the scientific considerations involved in the development of gene therapy strategies and outlines some of the gene products that are currently being used. These interventional genetic approaches will be reviewed in the context of specific vascular disease processes, including atherosclerosis, restenosis, and thrombosis. Gene therapy will serve an enhancing and adjuvant role to evolving surgical therapies.  相似文献   
69.
70.
Hsieh PF  Chia LG  Ni DR  Cheng LJ  Ho YP  Tzeng SF  Chang MH  Hong JS 《Neuroreport》2002,13(3):277-280
Inflammation and neuronal degeneration of the substantia nigra (SN) occur in Parkinson's disease (PD). We studied the effects of intranigral lipopolysaccharide (LPS) injection on adult Sprague-Dawley rats. Locomotor activity measurement, neurotransmitter determination and perfusion fixation for immunohistochemistry were done on the 7th day. Bilateral LPS injection increased locomotor activity 2- to 3-fold. In the SN, dopamine (DA) and serotonin (5-HT) decreased but the ratios dihydroxyphenylacetic acid (DOPAC)/DA, homovanillic acid (HVA)/DA and 5-hydroxyindole-acetic acid (5-HIAA)/5-HT increased. In the striatum, DA, DOPAC, HVA, 3-methoxytyramine and epinephrine decreased but HVA/DA and 5-HIAA/5HT ratios increased. Unilateral LPS decreased dopamineric neurons ipsilaterally but increased contralaterally. This study provides the first evidence of behavioral hyperactivity, epinephrine suppression and neuronal plasticity in the LPS model of PD.  相似文献   
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