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1.
High level of divergence of male-reproductive-tract proteins, between Drosophila melanogaster and its sibling species, D. simulans 总被引:1,自引:0,他引:1
We compared male-reproductive-tract polypeptides of Drosophila melanogaster
and D. simulans by using two-dimensional gel electrophoresis. Approximately
64% of male-reproductive-tract polypeptides were identical between two
randomly chosen isofemale lines from these two species, compared with 83%
identity for third-instar imaginal wing-disc polypeptides. Qualitatively
similar differences were found between reproductive tracts and imaginal
discs when D. sechellia was compared with D. melanogaster and with D.
simulans. When genic polymorphism was taken into account, approximately 10%
of male- reproductive-tract polypeptides were apparently fixed for
different alleles between D. melanogaster and D. simulans; this proportion
is the same as that found for soluble enzymes by one-dimensional gel
electrophoresis. Strikingly, approximately 20% of male-reproductive- tract
polypeptides of either D. melanogaster or D. simulans had no detectable
homologue in the other species. We propose that proteins of the Drosophila
male reproductive tract may have diverged more extensively between species
than have other types of proteins and that much of this divergence may
involve large changes in levels of polypeptide expression.
相似文献
2.
Population-based data have not been readily available on relatively short-term changes in weight. Therefore, we sought to determine the nature of self-reported substantial (> 10%) weight change over one year in a representative sample of the US population which participated in the 1989 National Health Interview Survey (NHIS). Across all ages, a larger proportion of women than men reported both weight loss as well as weight gain of any amount (18.9% vs. 16.1% for weight loss and 20.0% vs. 16.1% for weight gain). In sex-specific logistic regression analyses, significant risk factors common to both sexes for substantial weight loss included divorced/separated marital status, smoking, increased number of blood pressure checks, increased BMI (body mass index) and increased number of bed days. Black race reduced the risk of weight loss for both men and women. Sex-specific risk factors for weight loss in men only were widowhood or never married marital status, while increasing age was a protective factor in women only. Concerning weight gain > 10% over the past year, increased number of blood pressure checks and having one or more diabetic parents were significant risk factors among both men and women; while never being married, increased age, BMI, and education exerted a protective effect in both sexes. For women only, risk factors for weight gain included black race, increased number of contacts with a health professional, and being unemployed. Intention to lose weight was associated with both weight gain and weight loss in both sexes, although it did not serve as a confounder in any of these relationships. A greater likelihood of substantial weight loss among women relative to men was diminished for persons with higher BMI, higher number of blood pressure checks, being widowed, divorced or separated, and intention to lose weight. A greater likelihood of substantial weight gain among women relative to men was diminished for persons with low BMI. The results of this cross-sectional study of weight change, involving a one-year follow-up period, generally correspond with the results obtained by longitudinal studies involving a longer follow-up. 相似文献
3.
A double blind study was undertaken to determine the effectiveness or oral prostaglandin E2 as a means of improving the pelvic score prior to induction of labour. 48 patients who were greater than 37 were gestation and who had Bishop scores of less than 6 entered the study. Ten tablets were given on an hourly regime. Of 25 patients in the prostaglandin group, 17 were considered successes (68.0%), whereas of 23 patients who received a placebo, 9 were successes (39.1%). No adverse effects were recorded. Prostaglandin E2 is therefore considered a safe and effective method for priming the unfavourable cervix prior to induction of labour. 相似文献
4.
Cytochrome P-448 (mol wt 55,000 Daltons) from rabbit liver was purified to a specific content of 16.6 nmol/mg. Mice were immunised with this preparation, their spleens removed and dissociated lymphocytes hybridised with myeloma cells. Four monoclonal antibodies against cytochrome P-448 were raised and partially characterised. All four antibodies interacted with cytochrome P-448 in intact microsomal fractions and selectively immunoadsorbed cytochrome P-448 from solubilised microsomal preparations. One of the antibodies inhibited benzo[a] pyrene hydroxylase activity in a reconstituted system, one had no effect on activity and two increased activity. The possible applications of such antibodies are discussed. 相似文献
5.
Elasmosaurid plesiosaurians are renowned for their immensely long necks, and indeed, possessed the highest number of cervical vertebrae for any known vertebrate. Historically, the largest count has been attributed to the iconic Elasmosaurus platyurus from the Late Cretaceous of Kansas, but estimates for the total neck series in this taxon have varied between published reports. Accurately determining the number of vertebral centra vis-à-vis the maximum length of the neck in plesiosaurians has significant implications for phylogenetic character designations, as well as the inconsistent terminology applied to some osteological structures. With these issues in mind, we reassessed the holotype of E. platyurus as a model for standardizing the debated cervical-dorsal transition in plesiosaurians, and during this procedure, documented a “lost” cervical centrum. Our revision also advocates retention of the term “pectorals” to describe the usually three or more distinctive vertebrae close to the cranial margin of the forelimb girdle that bear a functional rib facet transected by the neurocentral suture, and thus conjointly formed by both the parapophysis on the centrum body and diapophysis from the neural arch (irrespective of rib length). This morphology is unambiguously distinguishable from standard cervicals, in which the functional rib facet is borne exclusively on the centrum, and dorsals in which the rib articulation is situated above the neurocentral suture and functionally borne only by the transverse process of the neural arch. Given these easily distinguishable definitions, the maximum number of neck vertebrae preserved in E. platyurus is 72; this is only three vertebrae shorter than the recently described Albertonectes, which together with E. platyurus constitute the “longest necked” animals ever to have lived. 相似文献
6.
Kathleen?MB?VinetteEmail author Kathleen?M?Gibney Roy?Proujansky Paul?T?Fawcett 《BMC microbiology》2002,2(1):24
Background
We have previously reported that altered culture conditions (a broth media with shaking) could induce a strain of Helicobacter pylori to assume a long spiral morphology resembling that described for Helicobacter heilmannii. The present study was initiated to determine if other strains of H. pylori could be induced to assume that morphology and if doing so would alter the expression of immunodominant proteins. 相似文献7.
Markus K Muellner Barbara Mair Yasir Ibrahim Claudia Kerzendorfer Hannelore Lechtermann Claudia Trefzer Freya Klepsch André C Müller Ernestine Leitner Sabine Macho‐Maschler Giulio Superti‐Furga Keiryn L Bennett José Baselga Uwe Rix Stefan Kubicek Jacques Colinge Violeta Serra Sebastian MB Nijman 《Molecular systems biology》2015,11(2)
8.
Alexander JJ Umino Y Everhart D Chang B Min SH Li Q Timmers AM Hawes NL Pang JJ Barlow RB Hauswirth WW 《Nature medicine》2007,13(6):685-687
Loss of cone function in the central retina is a pivotal event in the development of severe vision impairment for many prevalent blinding diseases. Complete achromatopsia is a genetic defect resulting in cone vision loss in 1 in 30,000 individuals. Using adeno-associated virus (AAV) gene therapy, we show that it is possible to target cones and rescue both the cone-mediated electroretinogram response and visual acuity in the Gnat2 ( cpfl3 ) mouse model of achromatopsia. 相似文献
9.
R Moriggi Jr HS Di Mauro SC Dias JM Matos MB Urtado NF Camar?o IV Sousa Neto DC Nascimento RA Tibana CO Assump??o J Prestes CB Urtado 《Biology of sport / Institute of Sport》2015,32(4):289-294
Low intensity resistance exercise (RE) with blood flow restriction (BFR) has gained attention in the literature due to the beneficial effects on functional and morphological variables, similar to those observed during traditional RE without BFR, while the effects of BFR on post-exercise hypotension remain unclear. The aim of the present study was to compare the blood pressure (BP) response of trained normotensive individuals to RE with and without BFR. In this cross-over randomized trial, eight male subjects (23.8 ± 4 years, 74 ± 3 kg, 174 ± 4 cm) completed two exercise protocols: traditional RE (3 x 10 repetitions at 70% one-repetition maximum [1-RM]) and low intensity RE (3 x 15 repetitions at 20% 1-RM) with BFR. Blood pressure measurements were performed after 15 min of seated rest (0), immediately after and 10 min, 20 min, 30 min, 40 min, 50 min and 60 min after the experimental sessions. Similar hypotensive effects for systolic BP (SBP) were observed for both protocols (P < 0.05) after exercise, with no differences between groups (P > 0.05) and no statistically significant difference for diastolic BP (P > 0.05). These results suggest that in normotensive trained individuals, both traditional RE and RE with BFR induce hypotension for SBP, which is important to prevent cardiovascular disturbances. 相似文献
10.
Adelphocorisella australis sp. n. is described from north Queensland. This, the first representative of the genus known from Australia, is compared with the two previously described species, both from Japan. 相似文献