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21.
Dyeing is a state-of-the-art realm of textile engineering, however, the emphasis on petroleum-based products is now shifting towards green fibers, particularly, green manufacturing processes. In the present work, a natural mordant, sumac, was extracted and used alone and in combination with alum (a mineral mordant) in silk fibers dyeing with madder and Reseda green dye to make the green production of Iranian carpet possible. The FT-IR ATR spectra of the washed, mordanted, and mordanted dyed silk fibers revealed bonding between silk fibers and green materials. The color of the silk fibers dyed with madder and Reseda extraction was quantified in terms of CIELab (L*, a*, and b*) and K/S values. The effects of different treatments on fastness properties including light, wash, and rubbing fastness were assessed by ISO standard test method.  相似文献   
22.

Background

Attempts for early detection of gastric cancer have recently focused on host''s genetic susceptibility factors and gene-environment interactions. We have, herein, studied the association of MTHFR C677T single nucleotide polymorphism (SNP) and its interaction with Helicobacter pylori infection, smoking, age and gender on the risk of gastric cancer among an Iranian population.

Methods

Gastric cancer patients (n = 450) and cancer-free controls (n = 780) were studied for serum H. pylori-specific IgG antibodies by ELISA and MTHFR C677T polymorphism (SNP) by PCR-RFLP. Demographic and life style data were collected through patient interviews. Unconditional logistic regression model estimated odds ratio (OR) and the corresponding 95% confidence intervals (CI).

Results

The interactions of MTHFR genotype with H. pylori infection (P = 0.03), age (P = 0.049) and gender (P = 0.007) were statistically significant. Accordingly, MTHFR C677T carriers who were also positive for H. pylori infection exhibited 80% (OR = 1.8, 95% CI = 1.0-2.9) significant excess risk of non-cardia gastric cancer. Furthermore, subjects over the age of 50 or female subjects carrying MTHFR C677T SNP showed 40 (OR = 1.4, 95% CI = 1.0-2.0) and 100 (OR = 2.0, 95% CI = 1.2-3.2) percent increased risk of gastric cancer, respectively.

Conclusion

MTHFR C677T SNP seems to increase the risk of gastric cancer and the effect is significantly inflated by interactions with H. pylori infection, age and gender. Key Words: Helicobacter pylori, Smoking, Gender identity, Age group, Methylenetetrahydrofolate reductase  相似文献   
23.
In the present study, the effect of chronic oral administration of curcumin in the presence or absence of morphine and noloxone was investigated on the visceral nociception induced by acetic acid in rats. Intraperitoneal injection of acetic acid (1 mL, 2%) produced contractions in the abdominal musculature (writhes). The latency time to the beginning of the first writhe was measured and the total number of writhes in the 1 h after acetic acid injection was counted. The latency time to the beginning of the first writhe was significantly (p < 0.05) increased and the number of writhes was significantly (p < 0.05) decreased by curcumin (20 and 40 mg kg(-1) body weight). The same results were obtained after subcutaneous injection of morphine (1 mg kg(-1) b.wt.). Naloxone at the dose of 1 mg kg(-1) body weight had no effect on pain intensity. Curcumin significantly (p < 0.05) enhanced the effect of morphine on the visceral pain responses, however did not reverse the effect of naloxone. Present data suggest that in the acetic acid-induced visceral nociception of rats, curcumin may produce an antinociceptive effect and the endogenous analgesic opioid system is involved in the curcumin-induced antinociception.  相似文献   
24.
The present study was undertaken to assess the microbiological profile of fresh camel meat and the possibility of improving microbial quality and extending the refrigerated storage life of meat by using low-dose gamma irradiation. Camel meat samples were subjected to 0 (control), 1.5 and 3 kGy doses and stored at 3 +/- 1 degrees C. the microbial and sensory attributes were evaluated. Exposure to 1.5 kGy dose significantly reduced the initial counts of Aerobic Plate Counts (APCs), psychrophilic bacteria, Lactic Acid Bacteria (LAB), molds and yeasts, Staphylococcus aureus, Listeria monocytogenes and Enterococci. Moreover, Pseudomonas, coliforms and Escherichia coli were below the detection levels. Irradiation at 3 kGy significantly reduced the initial counts of APCs LAB and Enterococci by 99.5, 93.5 and 93.9%, respectively. Pseudomonas, coliforms, S. aureus, L. monocytogenes and E. coli were not found at dose of 3 kGy during entire storage period, also psychrophilic bacteria and molds and yeasts were below the detection levels during 6 days of storage. This study shows that irradiation had no significant effects on the sensory attributes of camel meat. Refrigerated shelf-life of the meat irradiated at 1.5 and 3 kGy were 15 and 21 days, respectively, compared to 7 days for non-irradiated controls.  相似文献   
25.
This study was designed to determine the effects of hormonal manipulation on stress responses in female and male pikeperch. Two-year-old cultured female and male broodstocks with an average weight of 337.4 ± 20.1 (mean ± SE; n = 16) and 318.7 ± 15.1 g (n = 16), respectively, were randomly allocated into four hormonal treatments each containing 4 fish. Two sexual groups of 16 fish for each gender were considered. Sexually mature male and female pikeperch were injected with either physiological saline solution (as control group), common carp pituitary extract (CPE), human chorionic gonadotropin (hCG) and or luteinizing hormone-releasing hormone analog (LHRHa2). The blood samples were taken before hormonal injection and after ovulation and spermiation. Then the plasma levels of stress indices (cortisol, glucose, and lactate) were determined. The results showed that all CPE-, HCG-, and LHRHa2- injected males produced sperm. In females treated with CPE and hCG, three of four ovulated, but none of LHRHa2- and saline-injected fish spawned. Significant changes in cortisol, glucose, and lactate levels were observed among the females injected with different hormones. Plasma cortisol and glucose levels increased significantly in males injected with CPE and females injected with hCG, but no significant change was observed in lactate levels before and after hormonal induction. Comparison of two sexes revealed significant differences in glucose levels for females in some groups before injection, while CPE-injected sexes showed significant changes in cortisol and lactate concentrations. The results indicated that the induction of ovulation or spermiation stimulated stress responses especially in female pikeperch, and therefore, all the procedures should be made to minimize the disturbance during the artificial spawning.  相似文献   
26.
Juvenile stellate sturgeon Acipenser stellatus were intraperitoneally injected with estradiol-17β (E2; 0 and 5 mg/kg fish) to investigate the possibility of sex reversal and also determine the changes in biochemical parameters. Five-month-old fish (40.9 ± 1.1 g) were injected every 3-week interval during a 190-day trial. At the termination of the experiment, final weight and other growth parameters including weight gain and specific growth rate, hepatosomatic and viscerosomatic indices were not affected by repetitive injection of E2. Hematological features of E2-treated fish showed significant reductions in number of red blood cells, hemoglobin concentration, hematocrit value and mean corpuscular hemoglobin (P < 0.05), but no significant changes were observed in number of white blood cells, mean corpuscular volume and mean corpuscular hemoglobin concentration (P > 0.05). Calcium, phosphorus, glucose, triacylglycerol, cholesterol, total protein and estradiol concentrations were significantly increased in fish injected with E2 (P < 0.001). Plasma progesterone and testosterone levels were noticeably lower in fish injected with 5 mg/kg E2 rather than the control fish (P < 0.001). Histological observations of gonads showed that all fish injected with 5 mg/kg E2 apparently feminized, while 66.6 % of the control group was female. These results revealed that the injection of E2 is an effective method for feminization of stellate sturgeon without having significant inhibitory effects on growth and survival.  相似文献   
27.
28.
One hundred eleven mares were examined and selected on the basis of some criteria (history of recent genital discharge and/or abortion, dystocia, retained placenta, rectovaginal rupture and/or failing to conceive after repeated services), rectal palpation, and ultrasound examination of genital tract. The mares were classified in 3 groups (young, middle age and old). During estrus, a specimen was taken by uterine swab and endometrial biopsy. Endometritis was diagnosed and graded on the basis of pathology results and treatment was done on the basis of culture and antibiogram tests. At the first step of treatment, uterine lavage with warm saline followed by intrauterine administration of a specific antibiotic, or povidone iodine solution, was done daily during estrus. If the mare had not responded to the first treatment, in the next steps systemic antibiotic therapy was also added to the mentioned treatment. The results showed that Escherichia coli was the most frequently isolated pathogen and response to the treatments was significantly better in the young mares with category IIA fibrosis of uterine pathology than that of two other groups. It was also found that there is no relationship among age and kind of pathogen to mare endometritis.

Introduction

Bacterial endometritis is the most common cause of subfertility.[1, 2, 3 and 4] In 1992, Kenney argued against the general use of the term “endometritis” to describe the two often quite separate conditions of endometrium: the degenerative changes often associated with age and parity. He suggested the use of the term “endometriosis” instead of the term “chronic degenerative endometritis” (CDE): the inflammatory infection that is divided to “acute endometritis” and “chronic infiltrative endometritis” (CIE). [5]In some mares, the bacteria becomes established and uterine infection develops in which the sources of uterine contamination include coitus, parturition, and reproductive examination.[2, 4 and 6] These mares remain persistently infected and are termed “susceptible” mares, which may have conformation defects such as pneumovagina, uterine pooling, and foaling injuries, which predispose them to endometritis. [7] There are some data indicating that age, parity, and barren years may have important bearing on the breeding prognosis of the mare. [8 and 9] In general, loss of resistance to infection is associated with advancing age and multiparity, factors that are frequently associated with increasing value of mares. [10] By far, Streptococcus zooepidemicus followed by E coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae are the most frequently isolated pathogens,[7 and 10] but there are a few reports that E coli, K pneumoniae, and Corynebacterium spp. are the most frequent isolates.[4 and 11] Endometrial cytology and culture samples often reveal evidence of inflammation and infection. To improve reproductive management of mares in Iran, this study was conducted to assess main causes of mare endometritis and also the relation of age and kind of pathogen to mare endometritis, plus the efficacy of treatment methods in problem mares.

Materials and methods

One hundred eleven mares of different breeds (Thoroughbred, Arab, cross-bred, and two native breeds including Kord and Turkaman) from 4 to 26 years of age were examined and selected during April 1996 to June 2001. They had a history of recent genital discharge and/or abortion, dystocia, retained placenta, rectovaginal rupture, and/or failing to conceive after repeated services. The sanitary condition of the foaling boxes was also noted. The mares were classified in three groups according to the age: (1) young (4-9 years old), (2) middle age (10-14 years old), and (3) old age (≥15 years old).Each mare was restrained in a stock. The vulvar discharge and pneuomovagina were recorded if present. Rectal palpation and ultrasound examination of genital tract were done to determine uterine tone and presence of uterine fluid. During the estrus, a double-guarded swab was passed per vagina into the uterus. The swab was kept in contact with the endometrium for a minimum of 20 seconds and was placed in transport media. In the laboratory the swab was cultured as described by Rickets.[12] An endometrial biopsy specimen was also taken, fixed, and processed as described by Rickets. [13] Endometritis was graded as described by Kenny and Doig. [14] Briefly, they are Grade I (Absent), Grade IIA (Mild), Grade IIB (Moderate), and Grade III (Severe). After specifying the causal organism of endometritis, treatment was done on the basis of culture and antibiogram tests as described by Asbury et al, [10] the antibiotics used for treatment were: gentamicin (intrauterine administration, 2-3 g), amikacin (2 g, intrauterine administration), potassium penicillin G (5 million units, intrauterine administration), and chloramphenicol (3 g, intrauterine administration). [10 and 15] A diluted solution of povidone iodine (0.2%) as uterine lavage was also used in cases whose uterine culture results were yeasts. The following protocol was carried out to treat bacterial endometritis at the first step:Uterine lavage with warm saline followed by intrauterine administration of specific antibiotic or povidone iodine (on the basis of uterine culture and antibiotic sensitivity test results) was done daily during estrus. Casslick operation was done in pneuomovaginal cases. In the next estrus, the uteri were examined by rectal palpation and ultrasonography procedure. If they were involuted, had enough tone and had no fluid, the mares were clinically defined to be treated and bred artificially with fresh semen collected from an approved fertile stallion (about 500 million progressive motile sperm) in Kenney's extender. If there was recurrent endometritis or the uterus was not involuted and/or had not enough tone or had some fluid in it, another specimen was taken by a double-guarded swab. On the basis of culture and antibiotic sensitivity test results, mares that had not responded to the first treatment were treated again with the first step protocol plus systemic antibiotic therapy (gentamicin, amikacin, or procaine penicillin G in bacterial-caused endometritis) or just flushed the uterus with saline and 0.2% povidone iodine solution (in yeast-caused endometritis and/or endometriosis). This treatment was also carried out daily during the estrus. Some of the mares that had not responded to the second treatment protocol were treated again (based on uterine culture and antibiotic sensitivity test results) for one to two times more in the next estrus phases as in the second step. The data were analyzed by χ2 test.

Results

Table 1 shows the pathogens isolated in three successive cultures from the uteri of the mares. Among 197 swabs were taken from the uteri of 111 mares, the cultures were positive in 175 instances in which the mixed organisms were isolated in 20 cases. The interesting point in these 3 successive cultures was the persistence of one Klebsiella infection detected in a mare belonging to the second group, in the all-performed treatments. The isolated P aeruginosa in a mare belonging to the third group had the same result. The combination of Candia albicans with E coli and/or E coli with Enterobacteriaceae were the most common feature of mixed micro-organisms isolated in the culture plates.  相似文献   
29.
In this study, natural and anthropogenic factors affecting the spatial distribution of topsoil mass magnetic susceptibility (χlf) were investigated in an arid region in Isfahan province, central Iran. A total of 100 surface (0–5 cm) soil samples were collected, and the χlf value of the soil samples was measured. High values of χlf in the east and northeast parts of the area indicated the occurrence of hilly igneous rocks and pediment geomorphic surface, enriched by ferrimagnetic minerals. In order to investigate the effects of human activities, multivariate geostatistics was applied to the results on the concentrations of eight heavy metals in surface soil samples. The results indicated that the spatial variability of second factor extracted by factor analysis, with high contribution of Zn, Pb and Cu, was well in agreement with the distribution of urban and industrial sites. This implied that magnetic particles accompanying the heavy metal emissions have increased χlf in the topsoil of the west of the area studied. Multiple linear regression analysis of χlf with studied factors revealed that the developed model explained about 64% of total variability in χlf in the studied area; and geology was identified as the most important controlling factor.  相似文献   
30.
Background:Variations in mtDNA-CN of PBLs, as a potential biomarker for GC screening has currently been subject to controversy. Herein, we have assessed its efficiency in GC screening, in parallel and in combination with sPG I/II ratio, as an established indicator of gastric atrophy. Methods:The study population included GC (n = 53) and non-GC (n = 207) dyspeptic patients. The non-GC group was histologically categorized into CG (n = 104) and NM (n = 103) subgroups. The MtDNA-CN of PBLs was measured by quantitative real-time PCR. The sPG I and II levels and anti-H. pylori serum IgG were measured by ELISA. Results:The mtDNA-CN was found significantly higher in GC vs. non-GC (OR = 3.0; 95% CI = 1.4, 6.4) subjects. Conversely, GC patients had significantly lower sPG I/II ratio than the non-GC (OR = 3.2; CI = 1.4, 7.2) subjects. The combination of these two biomarkers yielded a dramatic amplification of the odds of GC risk in double-positive (high mtDNA-CN-low sPGI/II) subjects, in reference to double-negatives (low mtDNA-CN-high sPGI/II), when assessed against non-GC (OR = 27.1; CI = 5.0, 147.3), CG (OR = 13.1; CI = 2.4, 72.6), or NM (OR = 49.5; CI = 7.9, 311.6) groups. Conclusion:The combination of these two biomarkers, namely mtDNA-CN in PBLs and serum PG I/II ratio, drastically enhanced the efficiency of GC risk assessment, which calls for further validations. Key Words: Biomarkers, DNA copy number variation, Mitochondrial DNA, Stomach neoplasms  相似文献   
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