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2.
Nature ; 568(7753): 521-525, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30971830

RESUMEN

Global dust storms on Mars are rare1,2 but can affect the Martian atmosphere for several months. They can cause changes in atmospheric dynamics and inflation of the atmosphere3, primarily owing to solar heating of the dust3. In turn, changes in atmospheric dynamics can affect the distribution of atmospheric water vapour, with potential implications for the atmospheric photochemistry and climate on Mars4. Recent observations of the water vapour abundance in the Martian atmosphere during dust storm conditions revealed a high-altitude increase in atmospheric water vapour that was more pronounced at high northern latitudes5,6, as well as a decrease in the water column at low latitudes7,8. Here we present concurrent, high-resolution measurements of dust, water and semiheavy water (HDO) at the onset of a global dust storm, obtained by the NOMAD and ACS instruments onboard the ExoMars Trace Gas Orbiter. We report the vertical distribution of the HDO/H2O ratio (D/H) from the planetary boundary layer up to an altitude of 80 kilometres. Our findings suggest that before the onset of the dust storm, HDO abundances were reduced to levels below detectability at altitudes above 40 kilometres. This decrease in HDO coincided with the presence of water-ice clouds. During the storm, an increase in the abundance of H2O and HDO was observed at altitudes between 40 and 80 kilometres. We propose that these increased abundances may be the result of warmer temperatures during the dust storm causing stronger atmospheric circulation and preventing ice cloud formation, which may confine water vapour to lower altitudes through gravitational fall and subsequent sublimation of ice crystals3. The observed changes in H2O and HDO abundance occurred within a few days during the development of the dust storm, suggesting a fast impact of dust storms on the Martian atmosphere.

3.
Sci Adv ; 7(7)2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33568473

RESUMEN

Isotopic ratios and, in particular, the water D/H ratio are powerful tracers of the evolution and transport of water on Mars. From measurements performed with ExoMars/NOMAD, we observe marked and rapid variability of the D/H along altitude on Mars and across the whole planet. The observations (from April 2018 to April 2019) sample a broad range of events on Mars, including a global dust storm, the evolution of water released from the southern polar cap during southern summer, the equinox phases, and a short but intense regional dust storm. In three instances, we observe water at very high altitudes (>80 km), the prime region where water is photodissociated and starts its escape to space. Rayleigh distillation appears the be the driving force affecting the D/H in many cases, yet in some instances, the exchange of water reservoirs with distinctive D/H could be responsible.

4.
Rev Esp Geriatr Gerontol ; 47(5): 210-3, 2012.
Artículo en Español | MEDLINE | ID: mdl-22868226

RESUMEN

BACKGROUND: The number of elderly patients with breast cancer is increasing, and a large proportion of these older patients do not receive conventional treatment. Clinical and biological characteristics of tumours at this age and survival according to local or systemic therapy were analysed. MATERIAL AND METHOD: A total of 96 consecutive early breast cancer patients over 80 years of age diagnosed in our Unit between January 2002 and September 2008 were retrospectively investigated. Of them, 54 underwent surgery with or without adjuvant hormonal treatment, and 42 received primary hormonal therapy. RESULTS: Tumours of patients 80 years old or older had more favourable biological characteristics, including expression of steroid receptors, and absence of c-erb B2 expression. Overall survival was 50 months for the group subjected to surgery, and 44 months for the group who did not undergo surgery. The survival free of local recurrence in the surgery group was 44 months, whereas it was 18 months in the non-surgery group. CONCLUSION: In a cohort of patients aged 80 years and older, survival was similar in those who received hormonal or surgical therapy, although the former had a shorter period of progression-free survival or local recurrence.


Asunto(s)
Neoplasias de la Mama/terapia , Anciano de 80 o más Años , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Femenino , Humanos , Estadificación de Neoplasias , Estudios Retrospectivos , Tasa de Supervivencia
5.
Medisur ; 12(2): 426-430, abr. 2014.
Artículo en Español | LILACS | ID: lil-760262

RESUMEN

La piometra es una acumulación de pus en la cavidad endometrial. Aparece cuando existe una estenosis del orificio cervical debida a procesos malignos de cuerpo uterino o de cérvix, tras tratamientos con cirugía o radioterapia y por atrofia senil. Se presenta el caso de una paciente de 84 años remitida al Servicio de Urgencias Hospitalarias del Hospital Universitario Basurto, en Bilbao, España por el médico de la residencia donde se encuentra institucionalizada debido a que presentaba fiebre mantenida desde hacía dos semanas, sin focalidad aparente, diagnosticada como infección urinaria y tratada con amoxicilina-clavulánico. Por los exámenes imagenológicos se diagnosticó piometra en útero bicorne. Fue sometida al drenaje del piometra por vía vaginal, bajo anestesia general, tras dilatación mecánica del canal cervical. Se puso tratamiento con ertapenen. La evolución fue satisfactoria. Por lo poco común del caso se decidió su presentación.


Pyometra is an accumulation of pus in the endometrial cavity. It occurs when there is a stenosed cervical os as a result of malignant growths in the uterus or cervix, surgery or radiation therapy and senile atrophy. We present the case of an 84-year-old female patient referred to the Emergency Service of the Basurto University Hospital in Bilbao, Spain by the doctor of the nursing home where she is institutionalized because of a two-week history of continued fever without apparent cause. She was diagnosed with urinary tract infection and treated with amoxicillin/clavulanate. Based on the imaging tests, a pyometra in bicornuate uterus was diagnosed. She underwent drainage of the pyometra via the vaginal route, under general anesthesia, after mechanical dilation of the cervical canal. Treatment with ertapenen was prescribed. Progression was satisfactory. Given the rarity of this case, we decided to present it.

6.
Rev. cuba. cir ; 52(3): 218-222, jul.-sep. 2013.
Artículo en Español | LILACS | ID: lil-696698

RESUMEN

La gangrena gaseosa de la mama es una enfermedad rara y potencialmente mortal descrita como consecuencia de un traumatismo, por complicaciones infecciosas de la cirugía o por una trombosis venosa. También se ha relacionado ocasionalmente con otras causas tales como la diabetes mellitus, el envenenamiento con monóxido de carbono o la cirugía plástica. Presentamos un caso de gangrena gaseosa de mama en una mujer diabética de 74 años. Esta rara infección representa una emergencia médico-quirúrgica(AU)


Gas gangrene of the breast is a rare and potentially lethal disease following trauma, as a result of infectious complications from surgery or venous thrombosis. Other rare etiologies, such as diabetes mellitus, carbon monoxide poisoning, and plastic surgery, have also been reported as related to this illness. A case of gas gangrene of the breast found in a 74-year-old diabetic woman was presented in this paper. This rare infection is a medical and surgical emergency situation(AU)


Asunto(s)
Humanos , Femenino , Anciano , Enfermedades de la Mama/diagnóstico , Gangrena Gaseosa/patología , Mastectomía/métodos
7.
Rev. cuba. obstet. ginecol ; 38(4): 0-0, oct.-dic. 2012.
Artículo en Español | LILACS | ID: lil-665701

RESUMEN

La vasa previa es una afección rara asociada a una elevada mortalidad perinatal. Los vasos sanguíneos fetales cruzan por encima del orificio cervical interno y son el resultado de una inserción velamentosa del cordón umbilical. Se presenta un caso de sufrimiento fetal agudo letal causado por rotura de un vaso previo durante el segundo periodo del parto. Se comenta la etiología y el manejo clínico de esta afección.


Vasa previa is a rare condition associated with high perinatal mortality. Fetal blood vessels cross over the internal os and they are the result of an insertion cord velamentous. We report a case of fatal acute fetal distress caused by rupture of a vessel in the second period before delivery. We discuss the etiology and clinical management of this condition.

8.
Rev. cuba. cir ; 49(4): 69-73, oct.-dic. 2010.
Artículo en Español | LILACS, CUMED | ID: lil-584333

RESUMEN

La evisceración intestinal a través de la vagina después de una histerectomía es una complicación rara. Se presenta el caso de mujer posmenopáusica que presentó una evisceración transvaginal del intestino delgado después de que se le realizara una histerectomía abdominal. Se revisa la epidemiología, causas, diagnóstico y tratamiento(AU)


Transvaginal intestinal evisceration after hysterectomy is a uncommon complication. This is the case of a postmenopausal women presenting with transvaginal evisceration of the small intestine after a abdominal hysterectomy. Epidemiology, causes, diagnosis and treatment are analyzed(AU)


Asunto(s)
Humanos , Femenino , Anciano de 80 o más Años , Exenteración Pélvica/métodos , Complicaciones Posoperatorias/etiología , Histerectomía Vaginal/efectos adversos , Laparotomía/métodos , Antibacterianos/uso terapéutico
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