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1.
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   

2.
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   

3.
Airborne Pollen grains and Spores of three different cities viz., Al-Khobar (1987–1988), Abha (1991–1992) and Hofuf (1992–1993) in Saudi Arabia were studied using Burkard Volumetric Seven-Day Spore Trap. The data were analyzed in relation to their allergenic capability and one-year pollen and spore calendars were designed to correlate the patients’ symptoms as well as for selection of appropriate allergen extracts for diagnosis and treatment of allergic diseases. Amongst pollen group, Amaranthus viridis, Plantago spp., Chenopodium album, Ricinus communis, Rumex vesicarius, Juniperus spp., Parkinsonia aculeata, Prosopis spp., and Phoenix dactylifera were some of the frequent types. Amongst the fungal spores group Cladosporium, Smuts spores, Colored basidiospores, Alternaria, Ulocladium and Drechslera were the dominant types.  相似文献   

4.
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   

5.
Well-preserved Early Devonian continental and sparse marine palynomorph assemblages recovered from an exploration borehole located in northern Saudi Arabia are reported here and add to the understanding of Arabian Devonian stratigraphy. The units examined are the conventionally cored lower Murayr, upper Hammamiyat and Sha’iba Members of the Jauf Formation. A comparison with data sets from elsewhere on the Arabian Plate suggests that the units examined are Emsian in age. The age of the Murayr and Hammamiyat boundary interval is revised, based on the occurrence of Dibolisporites eifeliensis in northern Saudi Arabia, and placed in the Rhabdosporites minutus (Min) Interval Zone of the Emphanisporites foveolatus-Verrucosisporites dubia (FD) Oppel Zone. A new miospore, Apiculiretusispora densa with distinctive interradial thickenings, is described.  相似文献   

6.
Core samples from the QASIM-801 (QSIM-801) water well in the Qasim Region of central Saudi Arabia were investigated palynologically. The interval studied contains the transgressive succession from the Sajir Member of the Saq Formation to the Hanadir Member of the Qasim Formation, and yields well-preserved and abundant cryptospores, microphytoplankton (acritarchs and chlorophycean algae), and chitinozoans, indicative of a Darriwilian (Llanvirn) age. The lowermost portion of the cored interval from the upper Sajir Member consists of fine-grained sandstones deposited in tidal flat, and shallow-marine settings. It is characterized by abundant and diverse cryptospores (permanent tetrads, dyads, monads), cuticle-like phytoclasts, and a low diversity assemblage of marine palynomorphs. The upper part of the cored interval from the Hanadir Member is composed of hemipelagic to pelagic, organic-rich, graptolitic shales, and micaceous shales, of middle- to outer-shelf depositional settings, which yield abundant marine palynomorphs (acritarchs and chitinozoans). Cryptospore-bearing horizons are interspersed in the succession. Changes in the composition of palynomorph assemblages reflect higher frequency environmental changes within an overall transgressive succession. Four new acritarch species are described in open nomenclature, Tyrannus sp. A, Clypeolus sp. A,?Pulvinosphaeridium sp. A, and?Tinacula sp. A.  相似文献   

7.
Two new species of Eimeria were found from faecal samples of ten green peacocks (Pavo muticus) collected at Al-Kharj area, a central region of Saudi Arabia. Sporulated oocysts of Eimeria mutica n.sp. are ellipsoidal 23.1×17.4 (22.4–25.0×16.7–18.9) μm, with a smooth bilayered wall. A micropyle and bilobed polar body are present, but without an oocyst residuum. The sporocyst is an elongated-ovoid 13.7×6.2 (12.0–14.2×5.4–6.7) μm, with a Stieda body and a residuum. Sporulated oocysts of E. kharjensis n.sp. are subspherical 20.3×17.7 (19.0–21.5×16.2–18.7) μm, with a two layered wall and a single polar body. The micropyle is covered by a dome-shaped cap and the sporocyst is an elongate-ovoid 12.7×6.3 (11.9–13.5×5.4–6.8) μm, with a Stieda body. The sporocyst residuum is present as several small granules.  相似文献   

8.
Wheat (Triticum L.) is one of the major food crops of the world, and an important component of food security. The aim of this study was to collect and preserve seeds of wheat growing in eight regions of the Kingdom of Saudi Arabia (Al-Qassim, Asir, Al-Taif, Najran, AL-Baha, Jazan, Al-Madinah and Wadi Al-Dawasir) where wheat has been cultivated since ancient times. Sixty-one accessions/samples of wheat (Triticum aestivum) were collected and placed in dry storage (ex-situ conservation) at −18 °C (i.e. permanent storage). The accessions of local wheat have the ability to grow under harsh environmental conditions such as (high temperature, drought and salinity). Most of these samples were collected directly from farms, but a few were collected from markets. The most important criteria for ex-situ conservation is that seeds need to have a low moisture content (MC) and a high percentage viability. Seed MC was measured for all 61 accessions by the oven-drying method and seed viability was tested in three ways: percentage of germination, tetrazolium chloride testing, and X-ray radiography.The seed MC of the 61 accessions was uniformly very low (0.10–0.12%), and 97 to 100% of the seeds were viable. Thus, all 61 wheat accessions collected in this study have the initial requirements to remain viable for long periods of time in ex-situ conservation in the gene seed bank.  相似文献   

9.
Middle East respiratory syndrome is the acute respiratory syndrome caused by betacoronavirus MERS-CoV. The first case of this disease was reported from Saudi Arabia in 2012. This virus is lethal and is a close relative of a severe acute respiratory syndrome (SARS), which is responsible for more than 3000 deaths in 2002–2003. According to Ministry of Health, Saudi Arabia. The number of new cases is 457 in 2015. Riyadh has the highest number of reports in comparison to the other cities. According to this report, males are more susceptible than female, especially after the age of 40. Because of the awareness and early diagnosis the incidence is falling gradually. The pre-existence of another disease like cancer or diabetic etc. boosts the infection. MERS is a zoonotic disease and human to human transmission is low. The MERS-CoV is a RNA virus with protein envelope. On the outer surface, virus has spike like glycoprotein which is responsible for the attachment and entrance inside host cells. There is no specific treatment for the MERS-CoV till now, but drugs are in pipeline which bind with the spike glycoprotein and inhibit its entrance host cells. MERS-CoV and SAR-CoV are from the same genus, so it was thought that the drugs which inhibit the growth of SARS-CoV can also inhibit the growth of MERS-CoV but those drugs are not completely inhibiting virus activity. Until we don’t have proper structure and the treatment of MERS-CoV, We should take precautions, especially the health care workers, Camel owners and Pilgrims during Hajj and Umrah, because they are at a higher risk of getting infected.  相似文献   

10.
《Mammalian Biology》2014,79(6):409-413
This work represents the most extensive genetic study of the grey wolf (Canis lupus Linnaeus, 1758) in Arabia and the first considering genetic data from multiple locations within Saudi Arabia. Previous suggestion of the occurrence of two subspecies of wolves in Arabia is not supported by this study. The genetic evidence suggests that the wolves of Saudi Arabia are genetically variable and more closely related to the Eurasian wolf Canis lupus group (dog included) than to the Indian wolf C. l. pallipes. The genetic diversity observed for C. lupus in Saudi Arabia indicates that the subspecific status C. l. arabs should be retained for the Arabian wolf. What remains unclear is the degree to which genetic introgression from domestic dogs has influenced the composition and integrity of C. lupus in Saudi Arabia.  相似文献   

11.
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   

12.
Invasive species are capable of causing considerable damage to natural ecosystems, agriculture and economies throughout the World. Samsum ant, Brachyponera (Pachycondyla) sennaarensis has been a reason for medical implication and social nuisance through its poisonous and severely painful sting causing anaphylactic shock in many cases. We surveyed for the presence of the samsum ant in various provinces of Saudi Arabia. B. sennaarensis was the abundant Ponerinae species in human settlements. In the Eastern provinces, however, few samples were collected, and none were found in the Northern and Western provinces. Infestations of B. sennaarensis were particularly severe in the spring and summer seasons, when the ants make nests in moist areas and in cracks in cemented structures, whereas the extent of infestation reduced in winter seasons.  相似文献   

13.
An allergological study to evaluate allergenicity to Cladosporium, Burkard 7-Day Volumetric Spore Trap and Personal Volumetric air sampler (viable mode) were employed to conduct air sampling for 12 months in three regions of Saudi Arabia. The study was extended for a continuous 3rd year at one site. Skin prick testing (SPT) was also conducted on 605 allergic individuals using commercial extracts of C. herbarum. Cladosporium emerged to be the most prevalent genus in the outdoor environment constituting up to 25% of all fungal spores in the dry region and 37.1 and 41.2% in two coastal cities respectively. Amongst the species C. sphaerospermum, C. macrocarpum, C. cladosporioides and C. herbarum were noted. Maximum hourly concentrations up to 14 x 10(3) m(-3) were recorded in coastal region during winter months. Morning concentrations were higher at both city sites compared to afternoon concentration. SPT result revealed an overall 19.67% positive reactions with majority showing mild reactions.  相似文献   

14.
15.
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   

16.
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   

17.
Resistance to a number of organophosphorus insecticides and the carbamate propoxur has been detected in a field population of Culex quinquefasciatus Say from Jeddah, Saudi Arabia. Cross resistance studies indicate that the same mechanism(s) may produce resistance to the full range of these compounds.  相似文献   

18.
Leptadenia jazanica Y. Masrahi from the province of Jazan, southwestern Saudi Arabia is described as a new species and illustrated. The species differs from the other known nearest species of the genus, Leptadenia pyrotechnica, by decumbent to scrambling habit of stems and persistent leaves. In the same province also two new records belonging to the genera Canavalia (Fabaceae) and Craterostigma (Scrophulariaceae) were collected; they were identified as Canavalia virosa (Roxb.) Wight & Arn. and Craterostigma plantagineum Hochst.  相似文献   

19.
20.
Traditionally, in Middle Eastern countries, many cultures use chewing sticks of arak for medicinal purposes especially, for oral cleanliness care. It was used by Muslims for treatment of teeth and highly recommended to be used by Muslims during the whole day. Therefore, the present work aimed to determine the total phenolic content and total flavonoids in two Miswak extracts obtained from arak roots collected from two different localities in Saudi Arabia. They were extracted with aqueous ethanol (80%) and used to estimate in vitro their antioxidative abilities. The new findings showed that the two tested extracts contained significantly different amounts of both total phenolic content and total flavonoids. According to the increase of total phenolic contents and total flavonoids obtained from the two extracts, Miswak collected from the southern region was found to contain more contents than those collected from the middle region. The results of antioxidant activities of Miswak root extract obtained by using different in vitro methods were varied depending on the technique used. According to the malondialdehyde (MDA) method, hydrogen peroxide (H2O2) scavenging ability and 1,1-diphenyl-2-picrylhydrazyl (DPPH) methods, the two Miswak extracts exhibited to have high to very high antioxidant activities. Mostly, the values of antioxidant activities of Southern region have been shown to be always the highest.  相似文献   

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