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111.
The existence and characteristics of bone marrow T-cell progenitors have not yet been established in man. Several pieces of evidence such as the reconstitution of certain immunodeficiencies by bone marrow graft suggest that T-cell precursors are present in the bone marrow. We report the growth of T-cell colonies from bone marrow populations using PHA-stimulated lymphocyte-conditioned medium containing T-cell growth factor (TCGF). Rosetting experiments and complement-dependent cytotoxicity assays with monoclonal antibodies indicate that the bone marrow T colony-forming cells (T-CFC) are E- OKT 3- and la+, i.e., immature progenitors. The colonies derived from these cells have the phenotype of mature T cells: E + OKT 3 + la- with either helper (OKT 4+) and suppressor (OKT 8 +) antigens. These results suggest that a thymic microenvironment may not be necessary for the in vitro proliferation and differentiation of the T-cell lineage in adult humans. These methodologies may permit direct investigation of early phenomena concerning the T-cell lineage, such as the acquisition of self-tolerance, the formation of a repertoire of specificities, and the HLA restriction phenomena that we believe takes place before the thymic maturation. 相似文献
112.
Soil samples weighing 255.3 kg, collected from 50 villages of 5 visceral leishmaniasis (VL) endemic districts of Bihar state were examined for sandfly breeding, using the soil incubation method. Breeding of sandflies was detected in 46% of the villages and 7.3% of the soil samples examined. Intra-domestic soil was found to be infested with 2 species of sandflies, Phlebotomus argentipes Annandale and Brunetti and Phlebotomus papatasi (Scopoli). In comparison with human houses, P. argentipes was found to show greater propensity to breed in cattle sheds; breeding prevalences in villages and soil samples, for the species, were significantly higher in cattle sheds than in human houses. The preference for breeding sites by the sandflies appeared to be associated with the pH of the soil. P. argentipes thus preferred to breed in the alkaline soil of cattle shed, and P. papatasi in the soil with neutral pH, of human houses. The emergence of adult P. argentipes from soil samples was mainly observed from April to October. 相似文献
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Matthew S. Yong Pankaj Saxena Ammar M. Killu Sean Coffey Harold M. Burkhart Siu-Hin Wan Joseph F. Malouf 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2015,42(4):372-376
Transesophageal echocardiography continues to have a central role in the diagnosis of infective endocarditis and its sequelae. Recent technological advances offer the option of 3-dimensional imaging in the evaluation of patients with infective endocarditis. We present an illustrative case and review the literature regarding the potential advantages and limitations of 3-dimensional transesophageal echocardiography in the diagnosis of complicated infective endocarditis.A 51-year-old man, an intravenous drug user who had undergone bioprosthetic aortic valve replacement 5 months earlier, presented with prosthetic valve endocarditis. Preoperative transesophageal echocardiography with 3D rendition revealed a large abscess involving the mitral aortic intervalvular fibrosa, together with a mycotic aneurysm that had ruptured into the left atrium, resulting in a left ventricle-to-left atrium fistula. Three-dimensional transesophageal echocardiography enabled superior preoperative anatomic delineation and surgical planning. We conclude that 3-dimensional transesophageal echocardiography can be a useful adjunct to traditional 2-dimensional transesophageal echocardiography as a tool in the diagnosis of infective endocarditis. 相似文献
116.
Amulya K. Saxena Maria Steiner Michael E. Höllwarth 《Indian journal of pediatrics》2014,81(8):766-769
Objective
To analyze unintentional straddle injuries in girls with regards to epidemiology, etiology and injury management.Methods
The hospital database was retrospectively reviewed (1999–2009) for female patients managed for genital trauma. Patients were evaluated based on age, causative factors, type of injury, area of genitals affected, management and outcomes.Results
Straddle injuries were documented in 91 girls with age ranging from 1 to 15 y (mean?=?6.3 y; median?=?6.1 y). The causes of injuries were falls at home (n?=?31) or outdoors (n?=?27), and sport activities (swimming pool n?=?11, skating n?=?11, bicycle n?=?9 and scooter n?=?2). Most of the injuries were lacerations. Injuries involved major labia (n?=?56), minor labia (n?=?45) and introitus vaginae (n?=?15). Twelve children received outpatient treatment. Inspection under anesthesia was performed in 79 patients, with 76 requiring sutures. While hematuria was observed in 18 patients, cystoscopy did not reveal lesions in the urethra or bladder. Associated injuries were femur fracture (n?=?1), lower extremity lacerations (n?=?4) and anal lesions (n?=?2). Follow-up investigations were uneventful; however one patient developed a secondary abscess and another secondary hyperplasia of the labia minor.Conclusions
Falls and sports are major causes of straddle injuries with a peak at the age of six years. Lacerations are the most common injuries and often require surgical management. Urinary tract injuries and other associated injuries are relatively uncommon in girls with straddle injuries. 相似文献117.
Mohit Kehar Sunita Bijarnia Sian Ellard Jayne Houghton Renu Saxena I. C. Verma Nishant Wadhwa 《Indian journal of pediatrics》2014,81(11):1237-1239
Fanconi-Bickel Syndrome (FBS) is a rare autosomal recessive disorder of carbohydrate metabolism. The defect in the GLUT 2 receptors in the hepatocytes, pancreas and renal tubules leads to symptoms secondary to glycogen storage, glucose metabolism and renal tubular dysfunction. Derangement in glucose metabolism is classical with fasting hypoglycemia and post-prandial hyperglycemia. The authors report a 4-year-old boy who presented with failure to thrive, motor delay, protuberant abdomen and was noted to have huge hepatomegaly with glycogen deposition in liver, and renal tubular acidosis. Gene sequencing revealed homozygous mutation, c.1330T > C in SLC2A2 gene, thus confirming the diagnosis of FBS. Only three mutations have been reported from India so far. The primary reason for referral to authors’ hospital was for liver transplantation, but an accurate diagnosis led to avoidance of the major surgery and streamlining of treatment with clinical benefit to the child and family. 相似文献
118.
Vidya Sagar Sudheesh Pilakka‐Kanthikeel Ravi Pottathil Shailendra K. Saxena Madhavan Nair 《Reviews in medical virology》2014,24(2):103-124
Although highly active antiretroviral therapy (HAART) has resulted in remarkable decline in the morbidity and mortality in AIDS patients, controlling HIV infections still remain a global health priority. HIV access to the CNS serves as the natural viral preserve because most antiretroviral (ARV) drugs possess inadequate or zero delivery across the brain barriers. Thus, development of target‐specific, effective, safe, and controllable drug‐delivery approach is an important health priority for global elimination of AIDS progression. Emergence of nanotechnology in medicine has shown exciting prospect for development of novel drug delivery systems to administer the desired therapeutic levels of ARV drugs in the CNS. Neuron‐resuscitating and/or antidependence agents may also be delivered in the brain through nanocarriers to countercheck the rate of neuronal degradation during HIV infection. Several nanovehicles such as liposomes, dendrimers, polymeric nanoparticles, micelles, and solid lipid nanoparticles have been intensively explored. Recently, magnetic nanoparticles and monocytes/macrophages have also been used as carrier to improve the delivery of nanoformulated ARV drugs across the blood–brain barrier. Nevertheless, more rigorous research homework has to be elucidated to sort out the shortcomings that affect the target specificity, delivery, release, and/or bioavailability of desired amount of drugs for treatment of neuroAIDS. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Saurabh Kumar Gupta MD DM Anita Saxena MD DM Rajnish Juneja MD DM Gurpreet Singh Gulati MD 《Congenital heart disease》2014,9(4):E125-E128
Atresia of the left main coronary artery is a rare anomaly that, if left untreated, has an unfavorable outcome. We hereby report left main coronary artery atresia in a child with tetralogy of Fallot with absent pulmonary valve and discuss the possible developmental basis of the association. 相似文献