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1.
Nat Ecol Evol ; 7(6): 841-851, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37142743

RESUMEN

Alpine river biodiversity around the world is under threat from glacier retreat driven by rapid warming, yet our ability to predict the future distributions of specialist cold-water species is currently limited. Here we link future glacier projections, hydrological routing methods and species distribution models to quantify the changing influence of glaciers on population distributions of 15 alpine river invertebrate species across the entire European Alps, from 2020 to 2100. Glacial influence on rivers is projected to decrease steadily, with river networks expanding into higher elevations at a rate of 1% per decade. Species are projected to undergo upstream distribution shifts where glaciers persist but become functionally extinct where glaciers disappear completely. Several alpine catchments are predicted to offer climate refugia for cold-water specialists. However, present-day protected area networks provide relatively poor coverage of these future refugia, suggesting that alpine conservation strategies must change to accommodate the future effects of global warming.


Asunto(s)
Cubierta de Hielo , Ríos , Animales , Refugio de Fauna , Ecosistema , Biodiversidad , Invertebrados
2.
Bioorg Med Chem Lett ; 10(22): 2557-61, 2000 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-11086729

RESUMEN

From two related series of 2-(alkylthio)-pyrimidones, a novel series of 1-((amidolinked)-alkyl)-pyrimidones has been designed as nanomolar inhibitors of human lipoprotein-associated phospholipase A2. These compounds show greatly enhanced activity in isolated plasma. Selected derivatives such as compounds 51 and 52 are orally active with a good duration of action.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Lipoproteínas/metabolismo , Fosfolipasas A/antagonistas & inhibidores , Pirimidinonas/farmacología , Administración Oral , Animales , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/química , Estructura Molecular , Fosfolipasas A/metabolismo , Fosfolipasas A2 , Pirimidinonas/administración & dosificación , Pirimidinonas/química , Conejos
3.
Chest Surg Clin N Am ; 9(2): 267-90, ix, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10365263

RESUMEN

Successful pneumonectomy in humans was preceded by the development of techniques for lobectomy. If experience in the animal laboratory had not been ignored, fears regarding sudden occlusion of the pulmonary artery and the fate of the postpneumonectomy pleural space would have been allayed. Precise hilar dissection was facilitated by the development of endotracheal anesthesia, which had been used successfully in animal experiments for at least half a century.


Asunto(s)
Neumonectomía/historia , Europa (Continente) , Historia del Siglo XIX , Historia del Siglo XX , Estados Unidos
4.
Pediatrics ; 102(6): E62, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9832590

RESUMEN

OBJECTIVE: Posterior fossa hemorrhages may be underdiagnosed in surviving neonates, with cerebellar hemorrhage discovered in 10% to 25% of autopsy specimens from very low birth weight infants. Posterior fossa lesions have been difficult to visualize by the traditional ultrasonography approach through the anterior fontanelle. Late in 1994, routine posterior fossa imaging through the posterolateral fontanelle was instituted to improve the ultrasonographic visualization of the posterior fossa in neonates. METHODS: Infants identified with posterior fossa hemorrhage by cranial ultrasonography between 1994 and 1996 were followed prospectively through discharge and their clinical courses reviewed. Infants diagnosed with posterior fossa hemorrhage between 1991 and 1994 were identified retrospectively from a comprehensive radiology database to use in comparison. All infants surviving to discharge were entered into neurodevelopmental follow-up using standard developmental assessments. RESULTS: Approximately 525 infants underwent cranial sonography during the study period between October 1994 and September 1996, including 250 infants weighing <1500 g. Thirteen infants were identified with posterior fossa hemorrhage using the posterolateral fontanellar approach. In contrast, only 2 infants were identified with posterior fossa hemorrhage between 1991 and 1994 using traditional anterior fontanellar views. Six very low birth weight infants were identified with cerebellar hemorrhages not associated with supratentorial, intraventricular hemorrhage. Each hemorrhage had a clinically silent presentation and, in 5 infants, was not well-appreciated by anterior fontanellar images. Magnetic resonance imaging studies were performed on 5 of the 6 infants and confirmed a cerebellar lesion in the area of previous echo density on ultrasonography. No infant is exhibiting motor abnormalities on neurologic examination, although 4 infants are demonstrating cognitive, developmental delay. Follow-up, however, is limited to a corrected age of

Asunto(s)
Hemorragia Cerebral/diagnóstico por imagen , Enfermedades del Prematuro/diagnóstico por imagen , Hemorragia Cerebral/complicaciones , Fosa Craneal Posterior , Discapacidades del Desarrollo/etiología , Ecoencefalografía/métodos , Humanos , Recién Nacido , Recien Nacido Prematuro , Recién Nacido de muy Bajo Peso , Estudios Prospectivos , Sensibilidad y Especificidad
6.
Chest Surg Clin N Am ; 8(2): 281-94, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9619305

RESUMEN

In this article, the anatomy of the diaphragm and phrenic nerves is discussed, together with related surgical implications. Since the major cause of phrenic nerve injury is surgery, usually for congenital or acquired heart disease, incisions in the diaphragm that do not injure major branches of the phrenic nerve are also discussed. Diaphragmatic plication is usually required in infants less than 3 months of age, and older children may be managed by ventilatory support if electrophysiologic studies document the possibility of return of nerve function. In adults with normal pulmonary function, unilateral diaphragmatic paralysis is usually asymptomatic.


Asunto(s)
Diafragma/anatomía & histología , Nervio Frénico/anatomía & histología , Adulto , Diafragma/cirugía , Hernia Diafragmática/diagnóstico por imagen , Humanos , Nervio Frénico/lesiones , Radiografía , Parálisis Respiratoria/fisiopatología , Parálisis Respiratoria/terapia
8.
J Antibiot (Tokyo) ; 50(3): 237-45, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9127195

RESUMEN

The synthesis, antibacterial activity and stability to human dehydropeptidase-1 (DHP-1) of three small series of carbapenems carrying carbon-linked substituents at C-2 are described. C-2 Ethenyl carbapenems showed moderate antibacterial activity but poor stability to DHP-1, C-2 Oxyiminomethyl carbapenems demonstrated variable activity and stability C-2 alpha-(Hydroxy)benzyl carbapenems were the most promising and showed good potency and DHP-1 stability.


Asunto(s)
Carbapenémicos/síntesis química , Carbapenémicos/farmacología , Humanos , Relación Estructura-Actividad
9.
Clin Radiol ; 51(10): 702-5, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8893639

RESUMEN

OBJECTIVE: To present five cases of the rare solid and papillary neoplasm of the pancreas with pathological correlation and review of the literature. PATIENTS AND METHODS: Five patients (all female, two Caucasian, one Philipino and two Hispanic) with solid and papillary neoplasm of the pancreas were reviewed. Four patients were under 28 years of age but one patient was 44 years old at presentation. Review consisted of imaging (CT in all and ultrasound in three patients), gross pathological and histological appearance (5/5 specimens), immunohistochemistry (4/5 specimens) and clinical follow-up. RESULTS: All five tumours were successfully resected without recurrence. All tumours were well-encapsulated but showed a wide spectrum of solid peripheral tumour with central cystic degeneration on imaging. Cystic spaces corresponded to haemorrhagic necrosis on histology. One tumour showed rim calcification. Immunohistological staining showed variable expression of both exocrine and endocrine markers. CONCLUSION: Although non-specific, solid and papillary neoplasm of the pancreas is characteristically a benign, well-encapsulated solid tumor with varying degree of central necrosis in young female patients. No racial predilection was demonstrated in this small series.


Asunto(s)
Neoplasias Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/patología , Adolescente , Adulto , Femenino , Humanos , Tomografía Computarizada por Rayos X , Ultrasonografía
11.
Ann Thorac Surg ; 60(2): 489-90, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7646133
12.
Chest Surg Clin N Am ; 5(2): 205-21, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7613961

RESUMEN

Following a short historical note, the operative technique of anatomic resection of individual bronchopulmonary segments is described. Segmentectomy is suited ideally to the surgical management of inflammatory lesions and pulmonary metastases. The high local recurrence rate makes it unsuitable for the treatment of primary lung cancer, except in patients with severely compromised pulmonary function.


Asunto(s)
Neumonectomía/métodos , Bronquios/cirugía , Bronquitis/cirugía , Disección/métodos , Humanos , Neoplasias Pulmonares/secundario , Neoplasias Pulmonares/cirugía , Neumonectomía/efectos adversos , Neumonía/cirugía
13.
Ann Thorac Surg ; 57(2): 475-6, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8311618

RESUMEN

An improved method of thoracoscopic implantable cardioverter defibrillators implantation is described. "Mailslot" thoracotomy is more expeditious than thoracoscopic implantation via multiple ports. If required for adequate defibrillation thresholds, subxiphoid, subdiaphragmatic implantation of a defibrillator patch may be performed.


Asunto(s)
Desfibriladores Implantables , Toracotomía/métodos , Fibrilación Ventricular/terapia , Anciano , Humanos , Masculino
17.
Gastrointest Radiol ; 15(4): 291-5, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2210197

RESUMEN

Presence or absence of pancreatitis without symptoms attributable to pancreatitis was assessed by computed tomography (CT) in 31 patients who underwent CT following endoscopic retrograde cholangiopancreatography (ERCP) within a time interval of 0-9 days. Presence or absence of pancreatitis was proven by elevated or normal amylase, and/or surgery, and by symptoms related to pancreatitis. Twenty-five of the patients underwent ERCP without and six with sphincterotomies. Among the six patients, additional procedures included two stent placements, two balloon dilatations, and one basket retrieval. Eleven of 31 patients developed pancreatitis following ERCP. The incidence of pancreatitis was higher in the group with maneuvers (four of six patients or 66.7%) than that without maneuvers (seven of 25 or 28%). Asymptomatic pancreatitis was present in five of 31 patients or 16.1%, and three of these had CT evidence of severe pancreatitis. CT demonstration of pancreatitis following ERCP with or without maneuvers may not always indicate clinically relevant disease.


Asunto(s)
Colangiopancreatografia Retrógrada Endoscópica , Pancreatitis/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad
18.
AJR Am J Roentgenol ; 154(1): 73-8, 1990 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2104730

RESUMEN

The value of CT of the pelvis, 111In-labeled leukocyte scintigraphy, and contrast enema (pouchography) for detecting postsurgical complications was assessed in 44 patients with total colectomy, rectal mucosectomy, and ileoanal pouches. Ileoanal pouches were created as reservoirs from an ileal loop that was anastomosed to the dentate line of the anus and stayed connected to the remainder of the ileum. This pouch preserves the normal defecatory pathway and eliminates disease-producing mucosa. A total of 57 sets of examinations revealed 22 cases of normal postoperative findings, 22 of pouchitis, 13 of abscess, and three of fistula. Overall sensitivity for detecting complications with pouchography was 60% (18 of 30 findings); with CT, 78% (28 of 36 findings); and with scintigraphy, 79% (23 of 29 findings). Pouchitis was best diagnosed by scintigraphy (sensitivity, 80%), followed by CT (sensitivity, 71%) and pouchography (sensitivity, 53%). Only CT correctly diagnosed all cases of abscess. Fistulas were frequently missed by all three methods. If tests were combined, the overall sensitivity rose to 93% for the combination CT/scintigraphy and to 86% for CT/pouchography, but did not improve for pouchography/scintigraphy (78%). For evaluation of complications in patients with ileoanal pouches, CT should be the initial test. If an abscess is found, no further tests are needed. If CT findings are negative, a scintigram should be obtained. Our data did not establish a clear role for pouchography.


Asunto(s)
Canal Anal/cirugía , Íleon/cirugía , Radioisótopos de Indio , Complicaciones Posoperatorias/diagnóstico por imagen , Absceso/diagnóstico , Adolescente , Adulto , Anciano , Sulfato de Bario , Colectomía/efectos adversos , Diatrizoato , Enema , Femenino , Humanos , Enfermedades Intestinales/diagnóstico por imagen , Fístula Intestinal/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Cintigrafía , Tomografía Computarizada por Rayos X
19.
Laryngoscope ; 99(8 Pt 1): 819-21, 1989 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2755291

RESUMEN

The authors reviewed 25 cases of pharyngoesophageal replacement. A tubed pectoralis major myocutaneous flap was employed in ten cases where an adequate distal resection margin could be obtained above the thoracic inlet. Total gastric transposition was used in 15 cases where resection extended into the mediastinum. The overall rates of complications (52%), postoperative mortality (20%), and satisfactory deglutition (80%) were similar for both operations and were superior to those achieved with reconstructive procedures previously used by the authors. The choice of method is influenced by the length of the pharyngoesophagus to be replaced and the general condition of the patient. Gastric transposition is a more versatile operation and is adaptable to replacement of the entire esophagus if necessary, while the tubed pectoralis major myocutaneous flap has proven particularly effective for the rehabilitation of elderly and severely debilitated patients.


Asunto(s)
Esofagoplastia/métodos , Estómago/cirugía , Colgajos Quirúrgicos , Anciano , Anciano de 80 o más Años , Neoplasias Esofágicas/cirugía , Femenino , Humanos , Masculino , Métodos , Persona de Mediana Edad , Complicaciones Posoperatorias , Estudios Retrospectivos
20.
Am Rev Respir Dis ; 136(4): 1001-2, 1987 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3662224

RESUMEN

In patient with a chronic post-tuberculous bronchopleural cutaneous fistula (BPCF), minute ventilation, dead space, flow rates, arterial blood gas tensions, and oxygen consumption were measured during mouth breathing and after 30 min of steady-state breathing solely through the BPCF. Despite a 390-ml (18%) decrease in dead space when breathing took place through the BPCF, there were no significant changes in minute ventilation or respiratory rate. BPCF breathing was also associated with an increase in airways resistance as reflected by a 300-ml (35%) decrease in the FEV1 and a 16% decrease in the FEV1/FVC ratio. The increased resistance resulted in a 20 ml/min (18%) increase in oxygen consumption. Arterial blood gas tensions remained constant. We conclude that although ventilatory efficiency was not improved, this patient was able to satisfy his total minute ventilatory requirements, for the 30-min period, solely through BPCF breathing.


Asunto(s)
Fístula Bronquial/fisiopatología , Fístula/fisiopatología , Enfermedades Pleurales/fisiopatología , Respiración , Enfermedades de la Piel/fisiopatología , Fístula Bronquial/etiología , Enfermedad Crónica , Fístula/etiología , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Pleurales/etiología , Pruebas de Función Respiratoria , Enfermedades de la Piel/etiología , Factores de Tiempo , Tuberculosis Pulmonar/complicaciones
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