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1.
The conservation of five traditional crops is an important aspect of achieving national food security. In the present study, we aimed to collect and conserve germplasm of five local crops from the Jazan region of southwestern Saudi Arabia: Sorghum: Sorghum bicolor (L.) Moench); Barley (Hordeum vulgare L.) Millet (Pennisetum glaucum (L.) R. Br.); Sesame (Sesamum indicum L.) and Guar (Cyamopsis tetragonoloba (L.) Taub). Forty-one seed accessions of these five crops were collected and tested to determine seed moisture content (MC%) and quality as indicators of their potential to survive during long-term dry storage at ?18 °C (i.e. ex-situ conservation of genetic resources). Seed viability was assessed using germination tests, the tetrazolium chloride (TZ) test and X-ray imaging. Seeds of the five crops had very low MC% and high viability (fully developed embryos and germination >91%), indicating that they were of good quality and had high potential for long-term survival in gene banks. The genetic resources of these crops (seeds) have now been preserved at the gene-bank of King Abdulaziz City for Science and Technology (KACST-BGB), Riyadh, Saudi Arabia.  相似文献   

2.
A total of 292 randomly selected subjects belonging to two indigenous Arab tribes (Harbi and Ghamid) and two immigrant tribes (Mograbi and Mowallad), residents in Western Saudi Arabia, have been tested for genetic variants of six blood groups, four serum proteins, and five red cell enzyme systems. The distribution of the polymorphic systems was different between indigenous and immigrant tribes, and the present Arab population shows a considerable degree of admixture from the surrounding countries, in particular Africa.  相似文献   

3.
Preimplantation genetic diagnosis (PGD) testing is the practice of obtaining a cellular biopsy sample from a developing human oocyte or embryo, acquired via a cycle of in vitro fertilization (IVF); evaluating the genetic composition of this sample; and using this information to determine which embryos will be optimal for subsequent uterine transfer. PGD has become an increasingly useful adjunct to IVF procedures. The ability to provide couples who are known carriers of genetic abnormalities the opportunity to deliver healthy babies has opened a new frontier in reproductive medicine. The purpose of the PGD is enables us to choose which embryos will be implanted into the mother. In the present study 137 families who had undergone IVF at Habib Medical Centre, were enrolled for the PGD analysis. The couple visited the clinic for the sex selection, recurrent fetal loss and with the recurrent IVF failure. 802 embryos were tested by the biopsy method and 512 are found to be normal and 290 were abnormal embryos. In this study only 24% of the embryos were transferred and the remaining was not transferred because of the abnormalities or undesired sex of the embryos. The structural and numerical abnormalities were found to be 16.8%.  相似文献   

4.
Conservation in the Kingdom of Saudi Arabia is relatively young, yet have made considerable gains in conservation through strategic proclamation and reintroductions. Changes in land use, illegal hunting and competition with domestic stock has decimated the native ungulates, meaning that the survival of the native ungulate species is now completely dependent on protected area network. The challenge is to sustain this network to make meaningful conservation impact into the future. We review the status of ungulate conservation in Saudi Arabia and highlight that the conservation strategy is well developed. The major challenge faced in conservation in Saudi Arabia now is to implement what has been sanctioned.  相似文献   

5.
Two new megaspore species, Biharisporites jubahensis and Verrucisporites yabrinensis, are described from the Middle Devonian Jubah Formation of south central Saudi Arabia. Miospore-based biostratigraphy indicates that the age of the megaspore-bearing interval is no older than the early Givetian Geminospora lemurata Interval Zone, and not younger than Givetian. The presence of similar species in both Arctic Canada and Saudi Arabia suggests that the megaspore-producing plants achieved wide distribution in the Middle Devonian.  相似文献   

6.
Well-preserved palynomorph assemblages are recovered from the Devonian Jauf and Jubah formations in five shallow boreholes in the northern part of Saudi Arabia. These fully cored boreholes overlap stratigraphically to form a 1640 ft composite sequence. Miospores dominate the palynological assemblages of most samples. The assemblages are mainly composed of trilete spores but also contain cryptospores and monolete spores. One new genus, sixteen new species and two new varieties of miospores are described from the studied assemblages: Artemopyrainconspicua nov. sp., Artemopyrarecticosta nov. sp., Camarozonotriletesfilatoffii nov. sp., Camarozonotriletesrugulosus nov. sp., Cymbohilatesbaqaensis nov. sp., Cymbohilatescomptulus nov. sp., Cymbohilatesheteroverrucosus nov. sp., Cymbosporitesasymmetricus nov. sp., Dibolisporitespilatus nov. sp., Dictyotriletesbiornatus nov. sp., Gneudnasporadivellomedia (Chibrikova) Balme, 1988 var. divellomedia, Gneudnasporadivellomedia (Chibrikova) Balme, 1988 var. minor nov. var., Latosporitesovalis nov. sp., Scylasporacostulosa nov. sp., Squamisporaarabica nov. gen. and sp., Stellatisporamulticostata nov. sp., Zonotriletesarmillatus nov. sp. and Zonotriletessimplicissimus nov. sp. Their stratigraphic distribution is compared to the well-established Devonian West European zonation of Streel et al. (1987) (Streel, M., Higgs, K.T., Loboziak, S., Riegel, W., Steemans, P., 1987. Spore stratigraphy and correlation with faunas and floras in the type marine Devonian of the Ardenne-Rhenish region. Review of Palaeobotany and Palynology 50, 211-219). A late Pragian-Givetian age is suggested for this sequence. No characteristic Eifelian taxa are recorded, but this could be explained by a gap in palyniferous samples.  相似文献   

7.
In the Kingdom of Saudi Arabia (KSA), hospital and population based statistics have shown that breast cancer has the highest crude frequency rate among Saudi women. The scarcity of reports about the disease in the KSA has been the impetus to this analysis about breast cancer in the eastem province of KSA. Data on female patients with invasive breast carcinoma seen at King Fahd Hospital of the University in the eastern province of KSA, were retrospectively reviewed. The analysis intended to examine the pattern of the disease and the outcome for patients. Between 1985 and 1995, 292 patients were identified. Their median age±SD (standard deviation) was 42±10.5 years. Most patients were younger than 50 years (78%) and were predominantly premenopausals (79%). Only 25 (9%) of patients had stage I cancer, whilst 130 (44%), 90 (30%), and 47 (16%) had stage II, III, and IV, respectively. Among patients with known axillary nodal status (242 patients), only 37% were node-negative whilst 32% and 31% had 1–3, and ≥4 positive nodes, respectively. Adjuvant chemotherapy and tamoxifen were commonly offered; nonetheless, other adjuvant modalities were rarely utilised. The median follow-up ±SD of all patients was 62.3±8.9 months: 152 patients (52%) were alive with no evidence of disease, 25 (9%) were alive with evidence of disease, and 115 (39%) were dead from breast cancer or its related complications. The median survival of the entire group was not obtained, but the 10-year projected survival was 55%. For stage I and II patients, 118 (76%) were alive with a projected 10-year actuarial survival of 64%. On the other hand, only 51 (57%) of patients with stage III disease were alive with a median survival of 41.5 months (95% Confidence interval (CI), 18.9 to 51.3). Patients with stage IV disease demonstrated a poor outcome with a median survival of 23.5 (95%, CI 12.2 to 31.4). Multivariate analyses were performed to explore the influence of independent variables on overall survival (OS) for patients with non-metastatic disease. Besides the expected adverse effect of disease progression, the favourable influence of adjuvant chemotherapy and tamoxifen prevailed. The amount of benefit gained from tamoxifen, however, was small. Similar analyses were undertaken to determine the influence of independent variables on progression-free survival (PFS). These analyses ascertained the adverse effects of advanced stage and the favourable impact of adjuvant chemotherapy. Breast cancer in the KSA has features that are distinctive from those of industrialised countries. Survival data, however, were comparable. The favourable influence of adjuvant chemotherapy was evident on both OS and PFS. Adjuvant tamoxifen, however, had little effect. Due to its infrequent use, the role of other adjuvant modalities could not be asserted.  相似文献   

8.
Selenium (Se) is a naturally occurring trace element that is essential for animal and human nutrition, but the range between dietary requirements and toxic levels is relatively narrow. In this review, we are interested in the beneficial effects of selenium and we report on a number of studies of the selenium status of different populations in Saudi Arabia. The Status reflects the geographical area inhabited by the populations. Apart from the few available studies reviewed here, no data on the human status of Se in Saudi Arabia has been obtained. A further objective of this paper is throw some the light on the direction of future studies.  相似文献   

9.
Middle phalangeal hair was found to be present in 71% if Saudi Arabian males. For those exhibiting this trait, the frequency of combinations of digits with hair was similar to the frequency in other populations.  相似文献   

10.
This study was conducted to investigate phytophagous and predatory mites associated with vegetable plants in Riyadh, Saudi Arabia. Eight phytophagous and 10 predacious mites were collected from 14 species of vegetable crops covering five major production localities. Out of these 18 mite species, 13 species are new to the mite fauna of Saudi Arabia. In addition, the two species, Tenuipalpus punicae and Agistemus exsertus, are reported for the first time on vegetable crops in Saudi Arabia. For each mite species found, notes on host plant association and occurrence period are given. An illustrated key for the identification of the 18 mite species reported in this study is provided and this can be used to improve the IPM programs by applying the local natural predatory mites in controlling mite pests in Saudi Arabia.  相似文献   

11.
12.
The ctenodactylids from the Lower and Middle Miocene of Saudi Arabia are represented by two species: Sayimys intermedius (Sen and Thomas, 1979) and Sayimys assarrarensis sp. nov. This new taxon differs from the other species of Sayimys by its larger size together with an association of characters such as the presence of a metalophulid II in d4 and the strength of the anteroloph and posteroloph in P4. A cladistic analysis involving Prosayimys flynni , Sayimys obliquidens , S. assarrarensis sp. nov., S. intermedius, S. sivalensis, S. baskini , and Metasayimys curvidens is provided. Sayimys assarrarensis sp. nov. nests between Sayimys obliquidens and Metasayimys curvidens as a relatively primitive taxon.  相似文献   

13.
Although Human Adenoviruses outbreaks are rare, there still could be a potential chance for those viruses to mutate and spread quickly in human populations with severe public health and socioeconomic consequences. Outbreaks often spread fairly quickly with considerable morbidity/mortality. Saudi Arabia’s geopolitical and religious significance bring with it, millions of pilgrims, and tourists yearly. This presents a significant potential for HAdVs epidemics. This review shows that even with the mushrooming serotypes and genotypes, the scholarly knowledge on the nature, structure, transmission, and management of HAdVs is already well-established. Significant research is ongoing on pharmacological interventions, which, presently remain speculative and lacking in effectiveness. This review similarly uncovers a shortage of literature, both recent and dated, on epidemic keratoconjunctivitis in either Saudi Arabia or the Middle East.  相似文献   

14.
Electrophoresis for SDS-proteins and isoenzymes was applied to investigate the genetic variability within the tropical grasshopper Poecilocerus bufonius, which inhabits Saudi Arabia. Samples were selected from different localities that are encompassing the Sarawat Mountains in the west and An-Nafud desert in the north and middle. A range of 2 to 14 protein bands were recorded in the studied samples as measured by SDS-polyacrylamide gel electrophoresis, from which only two were common. The maximum number of protein bands has been recorded in the samples from the west and the minimum number has been recorded in the samples from the north and middle. Six arbitrary chosen enzymes were examined by native-polyacrylamide gel electrophoresis. They were peroxidase (Px), aldehyde oxidase (Ao), acid phosphatase (Acph), alcohol dehydrogenase (Adh), á and â ePsterase (Est). Fourteen presumptive gene loci and 26 polymorphic alleles have been recorded with the highest number of alleles in Taif and minimum number of alleles in Qassim. Adh, Px and Acph have not been recorded in samples from the localities of An-Nafud desert. The samples from Taif (Sarawat Mountains) were more genetically variable than the samples from other localities. Most of alleles were monomeric but only the Px-1 showed trimeric alleles in samples from Taif.  相似文献   

15.
Blepharis saudensis, from small islands in the Red Sea of Jazan Provence, Saudi Arabia, is described as a new species and illustrated. This species differs from other known species in this genus by having a combination of long stems, oblong-lanceolate to linear leaves with entire margins and pubescence.  相似文献   

16.
Fungi inhabiting household environments in the West, East and Central localities of Riyadh city were screened. The screened area included bedrooms, drawing rooms, living rooms, kitchens and bathrooms. The common genera of fungi isolated wereAlternaria, Aspergillus, Cercospora, Chaetomium, Cladosporium, Curvularia, Drechslera, Embellisia, Fusarium, Mucor, Penicillium, Rhizopus, Scytalidium, Trichoderma, Torula andUlocladium. Two uncommon generaNodulosporium andOidiodendron for Saudi Arabian mycoflora were also isolated. In all the localities, the highest number of fungal colonies per plate or per gram were found in the living rooms, followed by bedrooms. The number of colonies per plate or per gram was in general higher in densely populated than in less populated areas.  相似文献   

17.
The aim of the study was to detect the infection level of honey bees with Nosema apis and/or Nosema ceranae using microscopic and molecular analysis from indigenous honeybee race of eight Saudi Arabian geographical regions. A detailed survey was conducted and fifty apiaries were chosen at random from these locations. Infection level was determined both by microscope and Multiplex-PCR and data were analyzed using bioinformatics tools and phylogenetic analysis. Result showed that N. ceranae was the only species infecting indigenous honeybee colonies in Saudi Arabia. As determined by microscope, Nosema spores were found to be in 20.59% of total samples colonies, while 58% of the samples evaluated by PCR were found to be positive for N. ceranae, with the highest prevalence in Al-Bahah, a tropical wet and dry climatic region, whereas low prevalence was found in the regions with hot arid climate. Honeybees from all eight locations surveyed were positive for N. ceranae. This is the first report about the N. ceranae detection, contamination level and distribution pattern in Saudi Arabia.  相似文献   

18.
Queen mating frequency is an important reproductive trait of the western honeybee Apis mellifera. Yet, it demands more attention when investigated under extreme or confined ecosystems. Queen mating frequency of the Yemeni Honeybee A. m. jemenetica was estimated under Saudi Arabia desert conditions, Riyadh (24°71′36″N, 46°67′53″E). Mating of queens took place after 8–13 days from emergence. Duration of mating flight ranged between 26 and 39 min. Subsequently, six microsatellite loci were used to genotype queen's progeny (n = 30 workers/queen). The average number of drone alleles using workers genotypes ranged between 5.83 ± 0.31 and 6.33 ± 1.09. However, effective paternal allele number was extremely low and ranged between 3.35 ± 0.34 and 3.60 ± 0.40. This relatively low mating frequency of the Yemeni honeybee, A. m. jemenetica, might have striking effect on the overall colony survival. Providentially, this relatively low mating frequency does not impact colonial heterozygosity, shown in this study (0.66 ± 0.07–70 ± 0.04), adversely. These results may affect hive survivability and entails distinctive management practices under such conditions.  相似文献   

19.
Samples were collected from southern, central and eastern regions of Saudi Arabia using Malaise traps and sweep nets. Nine species of Tabanidae were identified, two for the first time from Saudi Arabia, Hybomitra peculiaris (Szilády) and Atylotus pulchellus (Loew).Therefore, the total number of Tabanidae in Saudi Arabia is 31 species. Remarks of the species recorded in this study were given. A key to the genera of Tabanidae occurring in the Arabian Peninsula is also provided. Available literature for Saudi Arabian Tabanidae is summarized and provided. It is concluded that the tabanid fauna of Saudi Arabia is more similar to that of the Palaearctic region than to the Afrotropical region.  相似文献   

20.
Seed-borne fungi from seeds of barley, canary, maize, oats, rice, rapeseed, red millet, sunflower, white millet and yellow millet were investigated. These seeds are available in the market as bird feed, supplied by companies in various countries as healthy and nutritious food for domestic birds. A total of 81 fungal species were isolated. The genusAspergillus was predominant with 23 species, followed byPenicillium with 18,Ulocladium with 7,Alternaria with 6 andChaetomium, Curvularia andDrechslera with 5 species each. Other genera isolated wereAureobasidium, Cladosporium, Fusarium, Mucor, Rhizopus andSyncephalastrum.  相似文献   

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