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981.
Muscle biopsy samples were obtained from healthy subjects in order to evaluate quantitative differences in single fibres of substrate (glycogen and triglyceride) and ion concentrations (Na+ and K+) as well as enzyme activity levels (succinate-dehydrogenase, SDH; phosphofructokinase, PFK; 3-hydroxyacyl-CoA-dehydrogenase, HAD; myosin ATPase) between human skeletal muscle fibre types. After freeze drying of the muscle specimen fragments of single fibres were dissected out and stained for myofibrillar-ATPase with preincubations at pH's of 10.3, 4.6, and 4.35. Type I (“red”) and II A, B, and C (“white”) fibres could then be identified. Glycogen content was the same in different fibres, whereas triglyceride content was highest in Type I fibres (2–3 × Type II). No significant differences were observed for Na+ and K+ between fibre types. The activity for the enzymes studied were quite different in the fibre types (SDH and HAD, Type I ? 1.5 × Type II; PFK Type I ? 0.5 × Type II; Myosin ATPase Type I ? 0.4 × Type II). The subgroups of Type II fibres were distinguished by differences in both SDH and PFK activities (SDH, Type II C > A > B; PFK, Type II B > A ? C). It is concluded that contractile and metabolic characteristics of human skeletal fibres are very similar to many other species. One difference, however, appears to be that no Type II fibres have an oxidative potential higher than Type I fibres.  相似文献   
982.
Permanent hapten-specific tolerance in B lymphocytes.   总被引:1,自引:4,他引:1       下载免费PDF全文
C J Elson  R B Taylor 《Immunology》1975,28(3):543-552
Tolerance to the hapten TNP was induced in mice congenic with CBA but bearing the Ig-b allotype (Ig-b mice). To induce a high degree of tolerance it was necessary to give five injections of TNP-sulphonate followed by an immunogenic challenge (alum precipitate of TNP-BSA with pertussis adjuvant). Lymph node or spleen cells from these mice were transferred, with or without an equal number of non-tolerant CBA spleen cells, to irradiated CBA recipients and these were challenged with a different TNP-protein conjugate. Anti-TNP antibody bearing the Ig-b allotype was then assayed separately from total anti-TNP, as a measure of the contributions made by tolerant and non-tolerant B-cell populations respectively. Tolerant lymph node cell did not depress the response of normal cells, nor did the normal cells 'break' the tolerance of the Ig-b population even when the latter had been treated with anti-T-cell serum and complement. No response was obtained from tolerant lymph node cells when the recipients were challenged at different time up to 12 weeks after transfer. By this time the control non-tolerant lymph node cells had also lost the capacity to respond. It is concluded that: (1) effectively permanent tolerance, which is not maintained by afferent mechanisms, can be induced in lymph node B cells; (2) B-cell tolerance can be greatly enhanced by immunogenic challenge; (3) spleen may contain a distinct population of B cells which is less susceptible to tolerance; and (4) the life-span of virgin lymph node B cells is probably less than 12 weeks.  相似文献   
983.
The histocompatibility antigen, HL-A8, was found to be elevated in patients with Sjogren's syndrome. Among 24 patients, the frequency of HL-A8 was 58% compared to 21% among controls (P < 0.001 after correction). With the addition of this disorder to the list of other autoimmune diseases associated with HL-A8, it now seems possible to postulate a single basis autoimmune defect gene in high linkage disequilibrium with HL-A8.  相似文献   
984.
IntroductionReproductive health problems, including sexual dysfunction and impaired fertility, are distressing and persistent after cancer treatment. However, recent reports suggest that reproductive health remains neglected in oncology settings.AimsWe conducted a survey to ascertain the prevalence of reproductive health problems in men and women treated in a comprehensive cancer center, and to estimate potential usage of clinical services to preserve fertility or to treat postcancer infertility and sexual dysfunction.MethodsWe mailed 800 questionnaires to men and women treated for cancer at our institution 1 to 5 years previously. Cancer sites and ages were chosen to maximize the risk of reproductive problems. We stratified the sample by living distance from our institution, to see if travel affected service utlilization. To provide a self-selected sample for comparison, another 200 questionnaires were made available in outpatient areas.Main Outcome MeasuresSelf-report questionnaire.ResultsThe return rate for the combined surveys was 29% for men and 26% for women. Cancer sites for self-selected respondents were almost identical to those in the postal cohort. Prevalence and types of sexual dysfunction were typical for surveys of cancer survivors, with 49% of men reporting new erection problems after cancer treatment and 45% of women noting loss of desire for sex and vaginal dryness. About a third of patients aged less than 50 years would have liked a fertility consultation before cancer treatment. Twenty to thirty percent wanted more information about premature ovarian failure or health risks for their children. Twenty-four percent of men and 21% of women would definitely want to visit a reproductive health clinic in the next year. Factors associated with wanting an appointment included self-selection to complete the survey and, for men, having less education.ConclusionIt should be feasible to establish a multidisciplinary reproductive health center in a comprehensive cancer center. Huyghe E, Sui D, Odensky E, and Schover LR. Needs assessment survey to justify establishing a reproductive health clinic at a comprehensive cancer center.  相似文献   
985.
The phenomenon of accessory ovary, initially described in 1864, is extremely rare. We report a case of an accessory ovary in a round ligament with endometriosis. At the time of laparoscopy a firm 2- to 3-cm mass was noted within the round ligament with a normal ovary visualized. Dissection and removal of the mass was performed. Histopathology revealed ovarian stroma and dense connective tissue with endometriosis. This case fulfills the criteria established in 1959 for accessory ovary and is the first case of an accessory ovary reported within the round ligament. A unique finding with the accessory ovary in this case is the presence of endometriosis. No reported cases exist of endometriosis within an accessory ovary. This information may be pertinent for evaluation of dysmenorrhea when no endometrial implants are present, or with the persistence or recurrence of endometriosis and pain after a bilateral salpingo-oophorectomy.  相似文献   
986.
IntroductionIn men, erectile dysfunction (ED) is an important issue. Data concerning ED in men with end-stage liver disease (ESLD) is limited, and the risk factors for ED in this population are still unknown.AimsTo determine the prevalence, timescale, and risk factors for ED in ESLD patients candidates to liver transplantation.MethodsPatients candidates for a liver transplantation were asked to participate in a mailed survey about sexual function. Among the 123 eligible men, 98 (84%) agreed to complete the questionnaire.Main Outcome MeasuresThe quality of erection was evaluated using the five-item International Index of Erectile Function (IIEF-5) score, and satisfaction for sexuality, using the patient-baseline Treatment-Satisfaction Scale (TSS) score. Other questions also focused on patient perception of changes over time.ResultsOn the overall population, 28 patients (29%) were nonsexually active. Among the 70 patients who were sexually active, 52 patients (74%) had ED. Regarding the development of ED, 50% of the patients perceived that a deterioration of erectile function occurred within the six previous months. The absence of sexual activity was more frequent in hepatitis B or C patients (P = 0.02). The risk factors for ED were alcohol intake (P = 0.03), tobacco use (P = 0.03), and cardiovascular disease (P = 0.004). The significant risk factors for having a low TSS score were having viral hepatitis (P = 0.01), and cardiovascular disease (P = 0.01).ConclusionPopulation of men with ESLD who are candidates for a liver transplantation is characterized by a high frequency of lack of sexual activity, and by a high prevalence of ED and should be targeted by interventions to improve sexual functioning. These preliminary data need further validation in prospective trial using more comprehensive questionnaires. Huyghe E, Kamar N, Wagner F, Capietto A-H, El-Kahwaji L, Muscari F, Plante P, and Rostaing L. Erectile dysfunction in end-stage liver disease men. J Sex Med 2009;6:1395–1401.  相似文献   
987.
To investigate the role of humoral factors in immunity, serum from cattle with naturally acquired immunity toSchistosoma bovis was injected intraperitoneally into calves that had been infected 4 weeks earlier with 10,000S. bovis cercariae. Serum was injected weekly until 12 weeks post-infection to a total of 4,500 ml per calf and controls received normal serum or saline. No significant difference in worm or in faecal or tissue egg counts were seen in the three groups of recipients in spite of the observation that the serum donors had proved highly resistant to experimental challenge. In a second experiment, pre-infection or 4-, 8- or 12-week post-infection serum from donors given a single experimental infection with 10,000S. bovis cercariae was injected intraperitoneally into groups of calves that had been infected 4 weeks earlier with 20,000S. bovis cercariae. Injections were given weekly up to week 10 post-infection to a total of 2000–3500 ml serum per calf. In calves injected with immune serum there was a reduction in faecal and tissue egg counts and in the numbers of worms recovered as compared with the controls. In recipients of 8- and 12-week serum the reductions in faecal and tissue egg counts were higher than those in worm recovery, suggesting that 8- and 12-week post-infection sera contained factors capable of causing, in addition to worm death, suppression of worm fecundity. This provides further evidence of the importance of fecundity suppression in immunity to schistosomiasis.  相似文献   
988.
Excised inside-out patches of vertebrate rod outer segment can support phototransduction. I have examined how ionic and metabolic conditions influence the functional properties of light-sensitive patches fromGekko gekko. I find that such patches retain a variable level of basal phosphodiesterase activity, which lowers the cyclic guanosine monophosphate (cGMP) concentration reaching the channels and reduces the dark current. The dose/response relationship for channel opening by cGMP varies among patches and this variability is only reduced by working in darkness with the phosphodiesterase inhibitor 3-isobutyl-1-methyl-xanthine (IBMX), suggesting that it is only partially due to phosphodiesterase activity. MgATP or MgGTP, but not Mg or ATP separately, increase this activity but a kinase does not appear to be involved. Intracellular monovalent cations also influence dark current intensity and light response kinetics. With 5 mM MgGTP, 1 mM IBMX, and 144 mM Li+, Na+, K+, or Rb+, dark current intensity and recovery time follow the respective sequences K+>Rb+>Na+>Li+ and K+<Rb+<Li+<Na+. Without IBMX, a dark current develops with K+ but not with Na+. These effects are not due to altered channel permeability (P) = 0.841.00 1.011.090.42], or differential Mg2+ block, but to modulation of guanylate cyclase, which overcomes phosphodiesterase when the major cation is K+ but not when it is Na+.  相似文献   
989.
990.
The purpose of this study was to estimate the extent of association of cervical screening in NSW women with socio-economic status (SES), rurality, and proportions of non-English speaking background (NESB) and Indigenous status. Data on women who had at least one Pap test over two years (January 1998-December 1999) were obtained from the NSW Pap test Register. Each local government area (LGA) was allocated to categories of population proportions of NESB and Indigenous status, a rurality classification based on population density and remoteness, and to an SES quintile. The odds ratios (OR) of having a Pap test were estimated and confounding adjusted by multiple logistic regression analysis. Implied Pap test rates in urban NESB and in rural Indigenous women were estimated from the modelled estimates. The adjusted OR for a Pap test in large rural centres (1.14) was significantly higher than those for metropolitan or capital city residents (0.9 and 1.0 respectively). Adjusted OR for a Pap test in other rural centres (0.73) and other remote areas (0.64) were significantly lower than those for metropolitan or capital city residents. In urban populations the lowest OR were in areas with both low SES and high proportion of NESB. The lowest OR for Pap screening in rural populations occurred in the most remote areas with the highest proportion of Indigenous women. For urban NESB women the biennial Pap test rate was estimated as 50%, and for rural Indigenous women 29%, compared with the NSW average of 59%.  相似文献   
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