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排序方式: 共有4302条查询结果,搜索用时 15 毫秒
81.
The first permanent molar (FPM) is commonly subject to significant compromise which may arise due to caries or endodontic complication, or from developmental anomalies such as hypoplasia. Compromised teeth with questionable prognosis may result in short and long-term clinical dilemmas. This review article highlights the factors that require careful consideration when a compromised FPM is detected and the importance of timely FPM extraction. Several clinical cases are described in detail to discuss possible treatment options from the orthodontic perspective. 相似文献
82.
The efficacy and outcome of bone marrow transplantation therapy following lethal irradiation were examined in syngeneic mice that had a hereditary macrocytic anemia (an/an) or were genotypically normal (+/+). Successful RBC and WBC replacement, based on blood cell parameters and donor genetic markers, were observed in all combinations of transplant therapy. Nevertheless, the an/an mice died prematurely several months after treatment, whether they received +/+ or an/an marrow cells. In contrast, the +/+ recipients of either +/+ or an/an marrow cells survived for at least 1 year after transplantation. Premature death of the an/an mice was associated with lymphopenia, anemia, kidney lesions, and severe pathogen-free pneumonitis. On the basis of our results, we hypothesize that the premature deaths of an/an mice are caused by a kind of chronic irradiation damage to which an/an mice are especially susceptible. 相似文献
83.
Farías Llamas OA López Ramírez MK Morales Amezcua JM Medina Quintana M Buonocunto Vázquez G Ruiz Chávez IE González Ojeda A 《Revista de gastroenterologia de Mexico》2005,70(2):169-179
Tuberculosis is a public health problem. The most common presentation is pulmonary disease. The diagnosis of any extrapulmonary forms are quite difficult. Clinical manifestations of gastrointestinal tuberculosis are non-specific and compatible with pathologies such as inflammatory bowel disease, advanced ovarian cancer, deep mycosis, yersinia infection and amebomas. Abdominal form is located at 6th place of the extrapulmonary forms, after lymphatic, genitourinary, osteoarticular, miliary and meningeal infections. Eventually, 25 to 75% of patients with abdominal tuberculosis will require surgery. These procedures should be limitated with the purpose to preserve small bowel. Resection should be limitated for complicated cases. The surgical indications include: Intestinal occlusion (15-60%), perforation (1-15%), abscesses and fistulas (2-30%) and hemorrhage (2%). CONCLUSIONS: In most of the cases, the diagnosis of peritoneal or intestinal tuberculosis is made during a laparoscopy or laparotomy even during surgery performed by different purposes. Excessive manipulation of the intraabdominal organs may produced unexpected bowel lesions, increasing morbidity and mortality. Medical treatment is highly effective in the resolution of moderate complications such as bowel obstruction. Resectional procedures should be reserved for complications like perforation, bleeding or stenosis non-suitable for stricturoplasty. 相似文献
84.
Aditya Ashok Mohammed S. Abusamaan Penelope Parker Scott J. Pilla Nestoras N. Mathioudakis 《Journal of general internal medicine》2021,36(5):1244
BackgroundThe blood glucose level triggering a critical action value (CAV) for hypoglycemia is not standardized, and associated outcomes are unknown.ObjectiveTo evaluate the clinical consequences of, and provider responses to, CAVs for hypoglycemia.DesignRetrospective cohort study at Johns Hopkins Hospital and Johns Hopkins Bayview Medical Center between April 1, 2013, and January 31, 2017.ParticipantsPatients with an ambulatory serum glucose < 50 mg/dL. Point-of-care capillary glucose and whole blood glucose samples were excluded.Main MeasuresElectronic medical record (EMR) review for providers’ documented response to CAV, associated patient symptoms, and serious adverse events.Key ResultsWe analyzed 209 CAVs for hypoglycemia from 154 patients. The median age (IQR) was 59 years (46, 69), 89 (57.8%) were male, and 96 (62.3%) were black. Provider-to-patient contact occurred in 128 of 209 (61.2%) episodes, among which no documented etiology was observed for 81 of 128 (63.3%), no recommendations were provided in 32 of 128 (25.0%), and no patient-reported hypoglycemic symptoms were documented in 103 of 128 (80.5%). Serious adverse events were documented in 4 of 128 episodes (3.1%), two required glucagon administration, and three required an ED visit. Provider-to-patient contact was associated with the patient having malignant neoplasm (adjusted OR 3.63, p = 0.045) or a hypoglycemic disorder (adjusted OR 7.70, p = 0.018) and inversely associated with a longer time from specimen collection to EMR result (adjusted OR 0.90 per hour, p = 0.016).ConclusionsThere is inconsistent provider-to-patient contact following CAVs for hypoglycemia, and the etiology and symptoms of hypoglycemia were infrequently documented. There were few serious documented adverse events associated with hypoglycemia, although undocumented events may have occurred, and the incidence of serious adverse events in non-contacted patients remains unknown. These findings demonstrate a need to standardize provider response to CAVs for hypoglycemia. Decreasing the lag time between sample collection and laboratory result reporting may increase provider-to-patient contact.KEY WORDS: Hypoglycemia, Critical action value, Ambulatory, Glucose 相似文献
85.
Density and function of inward currents in right atrial cells from chronically fibrillating canine atria 总被引:7,自引:0,他引:7
Yagi T Pu J Chandra P Hara M Danilo P Rosen MR Boyden PA 《Cardiovascular research》2002,54(2):405-415
OBJECTIVE: To determine whether I(Na) and I(CaL) are altered in function/density in right atrial (RA) cells from dogs with chronic atrial fibrillation (cAF dogs, episodes lasting at least 6 days) and whether the changes that occur differ from those in dogs with nonsustained or brief episodes of fibrillation (nAF dogs). METHODS: Using whole cell voltage clamp, sodium and calcium current density and function were determined in disaggregated RA cells from nAF, cAF and control atria (Con). Ca(2+) currents were studied with either Ca(2+) or Ba(2+) as charge carrier, as well as with either EGTA or BAPTA as the internal solution Ca(2+) chelator. RESULTS: After rapid atrial pacing, dogs can either fibrillate for short periods of time (nAF) or longer, more sustained periods (cAF). Both the Na(+) and Ca(2+) current decrease in cells of the nAF atria. Na(+) current density remains reduced in cAF cells with some slowing of recovery kinetics. Ca(2+) current density does not further decrease with persistent atrial fibrillation (cAF cells) remaining significantly different from Con cells. However, the difference in density of Ca(2+) currents between nAF and Con cells is negligible when Ba(2+) is charge carrier and when Ca(i) is quickly and effectively chelated with BAPTA. On the contrary, cAF I(BaL) densities remain significantly reduced compared to Con and nAF values when Ba(2+)/BAPTA conditions are used. CONCLUSIONS: Na(+) current density/function does not recover to Con values in cAF. Further these enhanced Ca(2+)-dependent inactivation processes contribute significantly to the reduction of I(CaL) density observed in nAF cells while reduction of Ca(2+) currents in cAF atria is probably by another mechanism 相似文献
86.
Epidemiology of sporadic bloody diarrhea in rural Western Kenya 总被引:1,自引:0,他引:1
Brooks JT Shapiro RL Kumar L Wells JG Phillips-Howard PA Shi YP Vulule JM Hoekstra RM Mintz E Slutsker L 《The American journal of tropical medicine and hygiene》2003,68(6):671-677
We conducted laboratory-based surveillance and a case-control study to characterize the epidemiology of bloody diarrhea in rural Western Kenya. From May 1997 through April 2001, we collected stool from 451 persons with bloody diarrhea presenting to four rural clinics. Cultures of 231 (51%) specimens yielded 247 bacterial pathogens: 198 Shigella (97 S. flexneri, 41 S. dysenteriae type 1, 39 S. dysenteriae type non-1, 13 S. boydii, 8 S. sonnei), 33 Campylobacter, 15 non-typhoidal Salmonella, and 1 Vibrio cholerae O1. More than 90% of the isolates (excluding Campylobacter) were resistant to trimethoprim-sulfamethoxazole and tetracycline, and more than 80% were resistant to ampicillin. Most (74%) ill persons received medication to which their isolate was resistant. Drinking Lake Victoria water and sharing latrines between multiple households increased risk of bloody diarrhea. Washing hands after defecating was protective. Providing safe drinking water and more latrines, and promoting hand washing could reduce the burden of illness from bloody diarrhea while limiting injudicious antimicrobial use. 相似文献
87.
The widespread assumption that cytoplasts generated from human polymorphonuclear leukocytes (PMNs) are vesicles consisting solely of cytoplasm surrounded by plasma membrane and devoid of granule activity remains to be tested. PMN cytoplasts were prepared by centrifugation of intact cells on a Ficoll step gradient in the presence of cytochalasin B. Two granule membrane markers, Mol, a fluorometrically detectable antigen, and cytochrome b, both of which have been shown to translocate to the plasma membrane during granule release, were compared for their activity in cytoplasts and intact PMNs. We found that the amount of Mol detected on the plasma membrane of intact PMNs, as compared with other membrane markers (such as antigens LFA-1 and beta 2m), increased 1.6- fold upon exposure of PMNs to Ficoll plus cytochalasin B prior to centrifugation. Another twofold increase in Mol expression occurred upon cytoplast preparation. Release of the granule enzymes, vitamin B12- binding protein, and lysozyme were also followed and correlated well (r = .78 and .92) with the amount of Mol antigen present on the cell surface. Cytochrome b was also found to be higher (1.4-fold) on plasma membranes isolated from cytoplasts than on plasma membranes isolated from intact control cells. These results indicate that some fusion of granule membranes and plasma membranes occurred during treatment of PMNs with Ficoll plus cytochalasin b and during cytoplast preparation. 相似文献
88.
Au R Seshadri S Wolf PA Elias M Elias P Sullivan L Beiser A D'Agostino RB 《Experimental aging research》2004,30(4):333-358
A previous publication presented normative data on neuropsychological tests stratified by age, gender, and education based on the Original Cohort of the Framingham Heart Study. Many contemporary investigations include subject samples with higher levels of education, a factor known to affect cognitive performance. Secular change in education prompted the reexamination of norms in the children of the Original Cohort. The study population consisted of 853 men and 988 women from the Offspring Study, free of clinical neurological disease, who underwent a neuropsychological examination, which included tests given to their parents in 1974 to 1976 as well as additional newer tests to provide a more comprehensive battery. The Offspring population overall was more evenly distributed by gender and better educated. Their performance on cognitive tests was superior to that of the Original Cohort. Multivariable analyses revealed that more years of education explained only a part of the cohort differences. These findings suggest that continued surveillance of each generation is necessary to document the impact that unique social and economic variables have on cognitive function. Here, the authors provide updated normative data. 相似文献
89.
Talmadge JE; Schneider M; Keller J; Ruscetti F; Longo D; Pennington R; Bowersox O; Tribble H 《Blood》1989,73(6):1458-1467
In a series of studies designed to extend our understanding of interleukin-2 (IL-2) and to study the effect of biologic response modifiers on bone marrow, we observed that administering recombinant human (rH) IL-2 to normal mice resulted in an increase in the frequency of colony-forming units-culture (CFU-C) in bone marrow. In addition, rH IL-2 was able to accelerate host recovery from cyclophosphamide (CTX)- or radiation-induced bone marrow depression and peripheral blood leukopenia. Not only can rH IL-2 accelerate, in a dose-dependent manner, the return of bone marrow, peripheral blood cellularity, and CFU-C frequency to normal levels following cytoreduction by CTX or irradiation, but it also significantly increases CFU-C frequency to greater than normal levels. Furthermore, rH IL-2 can significantly prolong survival of animals receiving a lethal dose of irradiation or CTX. Thus, multiple mechanisms are responsible for the synergistic therapeutic activity associated with rH IL-2 and CTX. rH IL-2 does not act only as an immunomodulatory agent in the presence or absence of suppressor T cells, but also accelerates host recovery from cytoreductive agents, resulting in decreased leukopenia and perhaps resistances to secondary infection. Thus, rH IL-2 plus chemotherapy may increase therapeutic activity against neoplastic disease, not only by adding immune stimulation to the direct antitumor effect of the drug but also by allowing delivery of higher, more effective doses of chemotherapy. 相似文献
90.
Fernández A Quintana G Matteson EL Restrepo JF Rondón F Sánchez A Iglesias A 《Clinical rheumatology》2004,23(6):523-526
Systemic lupus erythematosus is an autoimmune and inflammatory disease with multiple clinical manifestations, including arthropathy. The clinical presentation of articular involvement is variable, ranging from arthralgia without erosions or deformity to an erosive arthropathy and severe functional disability. A subset of patients with this articular involvement have Jaccouds arthropathy, and others have an arthropathy with clinical findings similar to rheumatoid arthritis that has been called rhupus. In this paper we review the historical evolution of concepts of lupus arthropathy, from deforming arthritis to rhupus, and conclude that rhupus is not a combination of rheumatoid arthritis and lupus. Instead, rhupus arthropathy should be regarded as a variant of the arthropathy of systemic lupus erythematosus. 相似文献