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1.
Incidence of assisted births, retained fetal membranes (RFM), and metritis were recorded in one hundred dairy cows from parturition through 14 days post-calving. Manual removal of RFM was not attempted. All RFM were excised inside the vulva and observations of natural RFM expulsion were recorded. Fifteen of 100 cows (15%) had assisted births, 27 (27%) had RFM, 8 (8%) had primary metritis not associated with other postpartum reproductive problems, and 26 (26%) had secondary metritis. Uterine swabs for culture were collected during the study from cows with postpartum reproductive problems. E . coli was the most common organism isolated (69.4%). Sensitivities of all isolates to penicillin, tetracycline, and triple sulfa were 44.0%, 59.5%, and 36.9% respectively. One of two antibiotic treatments were administered to cows with these postpartum reproductive problems. Treated animals received either 5 g. tetracycline powder IU on day 1 of treatment plus 10.5 million units procaine penicillin G IM on days 1, 2, and 3; or 4 Sulfaurea boluses IU on day 1. Despite the antibiotic treatments, 26 of 34 cows having either assisted birth and/or RFM developed metritis (76%). Neither treatment regimen was superior to the other. The poor results of antimicrobial therapy suggested the futility of routine administration of therapeutic agents for postpartum reproductive problems. Treatment failure was attributed to ineffective drugs or inadequate dosage regimens.  相似文献   
2.
Triglycerides within the cytosol of cells are stored in a phylogenetically conserved organelle called the lipid droplet (LD). LDs can be formed at the endoplasmic reticulum, but mechanisms that regulate the formation of LDs are incompletely understood. Adipose tissue has a high capacity to form lipid droplets and store triglycerides. Fat storage-inducing transmembrane protein 2 (FITM2/FIT2) is highly expressed in adipocytes, and data indicate that FIT2 has an important role in the formation of LDs in cells, but whether FIT2 has a physiological role in triglyceride storage in adipose tissue remains unproven. Here we show that adipose-specific deficiency of FIT2 (AF2KO) in mice results in progressive lipodystrophy of white adipose depots and metabolic dysfunction. In contrast, interscapular brown adipose tissue of AF2KO mice accumulated few but large LDs without changes in cellular triglyceride levels. High fat feeding of AF2KO mice or AF2KO mice on the genetically obese ob/ob background accelerated the onset of lipodystrophy. At the cellular level, primary adipocyte precursors of white and brown adipose tissue differentiated in vitro produced fewer but larger LDs without changes in total cellular triglyceride or triglyceride biosynthesis. These data support the conclusion that FIT2 plays an essential, physiological role in fat storage in vivo.  相似文献   
3.
The U.S. National Toxicology Program (NTP) conducted 2-year bioassays of commercial grade toluene diisocyanate (TDI) (80% 2,4-TDI and 20% 2,6-TDI) and 2,4-toluene diamine (TDA) and concluded that both were carcinogenic in rodents. In the TDI study, there was an unproven but likely formation of TDA either because of flawed test-substance handling and storage conditions and/or the atypical exposure conditions employed. Although the carcinogenic responses in both studies were qualitatively similar, several statistical analyses were performed to substantiate this possibility more rigorously. Seven different statistical approaches combine to yield a robust and consistent conclusion that, if only a small fraction (approximately 5%) of the dose of TDI were hydrolyzed to TDA in the TDI study, then that would be sufficient to explain the observed carcinogenic responses in the TDI study.  相似文献   
4.
We investigated the expression of proliferative cell nuclear antigen (PCNA) in zebrafish to delineate the proliferative hematopoietic component during adult and embryonic hematopoiesis. Immunostaining for PCNA and enhanced green fluorescence protein (eGFP) was performed in wild-type and fli1-eGFP (endothelial marker) and gata1-eGFP (erythroid cell marker) transgenic fish. Expression of PCNA mRNA was examined in wild-type and chordin morphant embryos. In adult zebrafish kidney, the renal tubules are surrounded by endothelial cells and it is separated into hematopoietic and excretory compartments. PCNA was expressed in hematopoietic progenitor cells but not in mature neutrophils, eosinophils or erythroid cells. Some PCNA+ cells are scattered in the hematopoietic compartment of the kidney while others are closely associated with renal tubular cells. PCNA was also expressed in spermatogonial stem cells and intestine crypts, consistent with its role in cell proliferation and DNA synthesis. In embryos, PCNA is expressed in the brain, spinal cord and intermediate cell mass (ICM) at 24 h-post fertilization. In chordin morphants, PCNA is significantly upregulated in the expanded ICM. Therefore, PCNA can be used to mark cell proliferation in zebrafish hematopoietic tissues and to identify a population of progenitor cells whose significance would have to be further investigated.  相似文献   
5.
Twelve mixed breed does were injected with different doses of prostaglandin F2α (PGF2α) or saline on day 144 of gestation. Four each received single intramuscular injections of 5.0 or 2.5 mg PGF, or 1.0 ml saline (controls). Systemic progesterone (P4) concentrations were determined daily from day 144 until the day of kidding. Does receiving 5.0 mg PGF2α, 2.5 mg PGF2α, or saline kidded within mean (± SD) hours and range (hours) of 35 ± 8.6 and 28–48, 43 ± 11.8 and 29–57, and 111 ± 79.1 and 41–200, respectively. Mean (± SD) concentrations of P4 (ng/ml) on the day of injection and on day 1 postinjection were 5.2 ± 2.6 and 0.7 ± 0.9, 5.3 ± 2.2 and 1.1 ± 1.0, and 6.4 ± 3.9 and 4.1 ± 2.6 for does receiving 5.0 mg PGF2α, 2.5 mg PGF2α, or saline, respectively. It was concluded that 5.0 mg and 2.5 mg PGF2α effectively shortened the interval from injection to parturition, but that this interval was not as predictable as that previously reported with 20 mg PGF2α.  相似文献   
6.
Ear implants that contained 3 mg Norgestomet or vaginal pessaries that contained 40 or 45 mg fluorogestone acetate were used to induce estrus in dairy goats in three herds in May. Ear implants or vaginal pessaries were left in place for 11 d. Cloprostenol (50 mug) and PMSG (500 IU) were administered i.m. 24 h prior to removal of ear implants or vaginal pessaries. After removal of vaginal pessaries, onset of standing estrus occurred in 22 23 goats (96%) at 20 +/- 4.7 h, in 19 20 goats (95%) at 22 +/- 6.3 h, and in 16 16 goats (100%) at 19 +/- 1.2 h in Herds A, B and C, respectively. After removal of ear implants, onset of standing estrus occurred in 25 25 goats (100%) at 19 +/- 4.9 h, in 20 22 goats (91%) at 22 +/- 7.0 h, and in 15 15 goats (100%) at 18 +/- 2.2 h in Herds A, B and C, respectively. Does were bred by natural service in Herds A and B, and by artificial insemination 28 h after vaginal pessary or ear implant removal in Herd C. Pregnancy rates were determined 39 to 53 d post breeding by real-time ultrasound. Pregnancy rates in goats with vaginal pessaries were 32, 55 and 6%; and in goats with ear implants they were 56, 67 and 27% in Herds A, B and C, respectively. Problems encountered included poor libido in some bucks, abortions in undersized yearling does, and loss of ear implants by three does (not included in the data). Statistically there was no difference in pregnancy rates between goats receiving vaginal pessaries or ear implants (P>0.10).  相似文献   
7.
A total of 11 cycling does weighing between 24 and 50 kg were injected with varying dosages of prostaglandin F(2)alpha (PGF(2)alpha) between 7 and 10 days into each estrous cycle. Five injections each of 1.25, 2.5, 5.0, or 7.5 mg PGF(2)alpha were alternated with five injections of 1.0 ml saline. Saline treated does served as controls. All does were teased twice daily with a buck and observed for signs of estrus for 5 days post-injection. Daily systemic concentrations of progesterone (P(4)) were determined by radioimmunoassay. The mean (+/- S.E.) hours from injection to estrus was 47 +/- 3.3, 42 +/- 4.3, 44 +/- 8.5, and 43 +/- 5.5 for does receiving 1.25, 2.5, 5.0, and 7.5 mg PGF(2)alpha, respectively. None of the does receiving saline exhibited estrus in the 5-day post-injection observation period. Mean (+/- S.E.) concentrations of systemic P(4) in all does on the day of injection was 4.22 +/- 0.45 ng/ml. Concentrations 24 hours post-injection were 0.21 +/- 0.02, 0.15 +/- 0.05, 0.17 +/- 0.04, 0.16 +/- 0.04, and 4.5 +/- 1.36 ng/ml for does receiving 1.25, 2.5, 5.0, and 7.5 mg PGF(2)alpha, and 1.0 ml saline, respectively. The results suggested that 1.25 mg PGF(2)alpha was effective for induction of estrus in the cycling goat.  相似文献   
8.
In this article, we report the synthesis of Na2Sr1‐x(PO4)F:Eux phosphor via a combustion method. The influence of different annealing temperatures on the photoluminescence properties was investigated. The phosphor was excited at both 254 and 393 nm. Na2Sr1‐x(PO4)F:Eux3+ phosphors emit strong orange and red color at 593 and 612 nm, respectively, under both excitation wavelengths. Na2Sr1‐x(PO4)F:Eux3+ phosphors annealed at 1050°C showed stronger emission intensity compared with 600, 900 and 1200°C. Moreover, Na2Sr1‐x(PO4)F:Eux3+ phosphor was found to be more intense when compared with commercial Y2O3:Eu3+ phosphor. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
9.

Background  

Considering the broad variation in the expression of housekeeping genes among tissues and experimental situations, studies using quantitative RT-PCR require strict definition of adequate endogenous controls. For glioblastoma, the most common type of tumor in the central nervous system, there was no previous report regarding this issue.  相似文献   
10.

Background

Understanding how DNA sequence polymorphism relates to variation in gene expression is essential to connecting genotypic differences with phenotypic differences among individuals. Addressing this question requires linking population genomic data with gene expression variation.

Results

Using whole genome expression data and recent light shotgun genome sequencing of six Drosophila simulans genotypes, we assessed the relationship between expression variation in males and females and nucleotide polymorphism across thousands of loci. By examining sequence polymorphism in gene features, such as untranslated regions and introns, we find that genes showing greater variation in gene expression between genotypes also have higher levels of sequence polymorphism in many gene features. Accordingly, X-linked genes, which have lower sequence polymorphism levels than autosomal genes, also show less expression variation than autosomal genes. We also find that sex-specifically expressed genes show higher local levels of polymorphism and divergence than both sex-biased and unbiased genes, and that they appear to have simpler regulatory regions.

Conclusion

The gene-feature-based analyses and the X-to-autosome comparisons suggest that sequence polymorphism in cis-acting elements is an important determinant of expression variation. However, this relationship varies among the different categories of sex-biased expression, and trans factors might contribute more to male-specific gene expression than cis effects. Our analysis of sex-specific gene expression also shows that female-specific genes have been overlooked in analyses that only point to male-biased genes as having unusual patterns of evolution and that studies of sexually dimorphic traits need to recognize that the relationship between genetic and expression variation at these traits is different from the genome as a whole.  相似文献   
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