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Micrometer‐sized spherical and rod‐shaped forms have been reported in many phosphorites and often interpreted as microbes fossilized by apatite, based on their morphologic resemblance with modern bacteria inferred by scanning electron microscopy (SEM) observations. This interpretation supports models involving bacteria in the formation of phosphorites. Here, we studied a phosphatic coprolite of Paleocene age originating from the Ouled Abdoun phosphate basin (Morocco) down to the nanometer‐scale using focused ion beam milling, transmission electron microscopy (TEM), and scanning transmission x‐ray microscopy (STXM) coupled with x‐ray absorption near‐edge structure spectroscopy (XANES). The coprolite, exclusively composed of francolite (a carbonate‐fluroapatite), is formed by the accumulation of spherical objects, delimited by a thin envelope, and whose apparent diameters are between 0.5 and 3 μm. The envelope of the spheres is composed of a continuous crown dense to electrons, which measures 20–40 nm in thickness. It is surrounded by two thinner layers that are more porous and transparent to electrons and enriched in organic carbon. The observed spherical objects are very similar with bacteria encrusting in hydroxyapatite as observed in laboratory experiments. We suggest that they are Gram‐negative bacteria fossilized by francolite, the precipitation of which started within the periplasm of the cells. We discuss the role of bacteria in the fossilization mechanism and propose that they could have played an active role in the formation of francolite. This study shows that ancient phosphorites can contain fossil biological subcellular structures as fine as a bacterial periplasm. Moreover, we demonstrate that while morphological information provided by SEM analyses is valuable, the use of additional nanoscale analyses is a powerful approach to help inferring the biogenicity of biomorphs found in phosphorites. A more systematic use of this approach could considerably improve our knowledge and understanding of the microfossils present in the geological record.  相似文献   
2.

Objective

To evaluate the results of medical and surgical treatment of sickle cell priapism.

Patients and methods

Between 01 January, 1995 and 31 December, 2005, 20 patients were treated for priapism in the services of Urology-Andrology and Haematology of the University Hospital, Brazzaville. Treatment included intracavernous injection of etilefrine and cavernospongious fistula.

Results

1) Five patients initially treated with transfusion and oral etilefrine without success were successfully cured after using the technique of Winter. 2) In 5 patients treated with intracavernous injection of etilefrine as first-line, 3 were cured and two failed, who were later cured using the technique of Winter. 3) Of 10 patients treated by Winter cavernospongious fistulas as first-line, 3 had recurrences and secondarily were successfully treated by the method of Al-Ghorab. Functional results in the long term include 25% lack of erection, 25% of erection failure and 50% of normal erection.

Conclusion

Treatment with intracavernous injection of etilefrine is effective before the 24th hour. Beyond this time, cavernospongious fistula yield better results.  相似文献   
3.
Cancer of the penis is rare. It often raises the issue of acceptability of the amputation of penis. We report a case of cancer of the penis following a late circumcision. The treatment consisted of amputation of two-thirds of the penis. The patient is alive without any local recurrence 2 years after surgery. Literature review suggests that this type of cancer is very rare. The factors associated with such cancer include lack of circumcision and infection with human papilloma virus.  相似文献   
4.
5.

Objective

To study risk factors and diagnostic investigations results of erectile dysfunction in urologic consultation in Brazzaville.

Method

It was a prospective study, which included 40 patients between 25 and 80 year-old seen for erectile dysfunction in the external urology-andrology consultation of the teaching hospital of Brazzaville, from December 2009 to August 2010. Information obtained from the investigation form included age, past history, risk factors, clinical and nonclinical characteristics and the international index of erectile function (IIEF-5) in its French translation. Epi Info software version 3.5.1 and SPSS 11.5 were used for data analysis. The Chi squared test was used to compare quantitative results and the analysis of variance (ANOVA) for qualitative results. The significance level was 0.05.

Results The frequency of erectile dysfunction was 14.7%, with an average age of 50.7 + 12.3 year-old (27?C77 years). The group 40 to 50 year-old was the most affected. The mean duration was 2.6 + 2.2 years (three months to nine years). Associated diseases were hypertension (22.5%) and diabetes (15%). The risk factors observed were alcoholism (75%), tobacco use (25%) and obesity (12.5%). The erectile dysfunction was severe in 47.5% of cases and severity was correlated with age. It was unbearable in 40% of cases

Conclusion

Erectile dysfunction was found in 14.7% of patients seen in urologic consultation. This number is underestimated because of modesty and taboos.  相似文献   
6.
The effects of temperature, water activity (aw), incubation time, and their combinations on radial growth and ochratoxin A (OTA) production of/by eight Aspergillus niger aggregate strains (six A. tubingensis and two A. niger) and four A. carbonarius isolated from Moroccan grapes were studied. Optimal conditions for the growth of most studied strains were shown to be at 25°C and 0.95 aw. No growth was observed at 10°C regardless of the water activity and isolates. The optimal temperature for OTA production was in the range of 25°C∼30°C for A. carbonarius and 30°C∼37°C for A. niger aggregate. The optimal aw for toxin production was 0.95∼0.99 for A. carbonarius and 0.90∼0.95 for A. niger aggregate. Mean OTA concentration produced by all the isolates of A. niger aggregate tested at all sampling times shows that maximum amount of OTA (0.24 μg/g) was produced at 37°C and 0.90 aw. However, for A. carbonarius, mean maximum amounts of OTA (0.22 μg/g) were observed at 25°C and 0.99 aw. Analysis of variance showed that the effects of all single factors (aw, isolate, temperature and incubation time) and their interactions on growth and OTA production were highly significant.  相似文献   
7.
Mosasaurus beaugei Arambourg, 1952 was based on isolated teeth from the Maastrichtian phosphatic deposits of Morocco. The recent discovery of new material, including skull and mandibular remains, improves our knowledge of this species. M. beaugei shares the following synapomorphies with the genus Mosasaurus: large teeth bearing two prominent carinae and with asymmetrical labial and lingual surfaces, the labial one being flattened and strongly facetted and the lingual one being convex; premaxillae with a small pointed rostrum and dentary without rostrum; palatal elements closely united; coronoid with very large ventromedial process overlying the prearticular. M. beaugei is characterised by the following autapomorphies: 12-13 maxillary teeth; marginal teeth bearing 3-5 prisms on the labial surface and 8-9 on the lingual one; palatine with posterior border concave and perpendicular to the long axis of the skull; splenial visible laterally on half of the dentary ventral surface; coronoid with anterior wing well developed and bearing two notches. M. beaugei is only known to date in the Maastrichtian phosphates of Morocco.  相似文献   
8.
A new species of the littoral cheloniid turtle Euclastes, E. acutirostris, is proposed, on the basis of a skull from the Palaeocene Phosphates of Morocco, the first turtle record from the Sidi Chennane area. It is estimated to be Danian-Thanetian in age, possibly younger than the previous Danian Moroccan specimens of Euclastes. It differs from the other species of Euclastes mainly by a more elongated and narrower snout, forming a small hook, the presence of a long and narrow spur-shaped postero-inferior process of the jugal, better delimiting the lateral skull emargination and the medially shorter palate, in relation to American Palaeogene specimens. This study indicates the necessity for a world-wide revision of the “Euclastes group” in order to redefine the taxa. It shows the potential interest of the group in the radiation and dispersion of the faunas of the Tethysian and Atlantic margins during the Cretaceous -Tertiary turnover.  相似文献   
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