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11.
Fifty-six infants with prenatally diagnosed hydronephrosis are reported. In all instances the diagnosis was confirmed postnatally and at renography 45 were obstructed; 38 obstructed kidneys (84%) and all of the non-obstructed kidneys had a differential function exceeding 40% of total function. Latterly we have come to recommend early pyeloplasty only if differential function of a renographically obstructed kidney is less than 40%; 6 early pyeloplasties were performed for this reason; 28 infants (30 renal units) were managed non-operatively and 18 of these (19 renal units) were reassessed renographically. In 11 the obstruction persists. Sonography demonstrated improving hydronephrosis in 8 kidneys with resolution in 5 and no change in 6. Of the other 10 infants (11 renal units), the hydronephrosis has improved in 4, resolved in 1 and remains unchanged in 6. Our experience suggests that neonatal and early pyeloplasty can be restricted to a modest number of infants in whom there is impaired renal function. In cases with normal function the natural history appears essentially benign and does not justify routine pyeloplasty.  相似文献   
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OBJECTIVE: To describe investigation of a tightly clustered outbreak of invasive group A streptococcal (GAS) disease associated with a high mortality rate in a long-term care facility (LTCF). DESIGN: Cross-sectional carriage survey and epidemiologic investigation of LTCF resident and employee cohorts. SETTING: A 104-bed community LTCF between March 1 and April 7, 2004. PATIENTS: A cohort of LTCF residents with assigned beds at the time of the outbreak. INTERVENTIONS: Reinforcement of standard infection control measures and receipt of chemoprophylaxis by GAS carriers. RESULTS: Four confirmed and 2 probable GAS cases occurred between March 16 and April 1, 2004. Four case patients died. The final case occurred during the investigation, before the patient was determined to be a GAS carrier. No case occurred during the 6 months after the intervention. Disease was caused by type emm3 GAS; 16.5% of residents and 2.4% of employees carried the outbreak strain. Disease was clustered in 1 quadrant of the LTCF and associated with nonintact skin. GAS disease or carriage was associated with having frequent personal visitors. CONCLUSIONS: Widespread carriage of a virulent GAS strain likely resulted from inadequate infection control measures. Enhanced infection control and targeted prophylaxis for GAS carriers appeared to end the outbreak. In addition to employees, regular visitors to LTCFs should be trained in hand hygiene and infection control because of the potential for extended relationships over time, leading to interaction with multiple residents, and disease transmission in such residential settings. Specific attention to prevention of skin breaks and proper wound care may prevent disease. The occurrence of a sixth case during the investigation suggests urgency in addressing severe, large, or tightly clustered outbreaks of GAS infection in LTCFs.  相似文献   
14.
A case with ocular (corneal crystals and retinal pigment epithelial mottling), muscle (oropharyngeal and hand weakness and atrophy), and renal (proteinuria and hypertension) abnormalities is described. We believe that this represents a previously unrecognized syndrome.  相似文献   
15.
Dermatologic changes associated with interleukin 2 administration   总被引:6,自引:0,他引:6  
A A Gaspari  M T Lotze  S A Rosenberg  J B Stern  S I Katz 《JAMA》1987,258(12):1624-1629
We have prospectively evaluated the skin changes that occurred in ten patients who were undergoing immunotherapy with interleukin 2 (IL-2) and autologous lymphokine-activated killer cells to treat cancer. Serial skin biopsy specimens were obtained before therapy (baseline), during IL-2 administration, and during IL-2/lymphokine-activated killer cell infusion. All patients developed an eruption that was characterized by macular erythema, with burning and pruritus of the skin. It began after two or three days of IL-2 infusion and was usually localized to the head and neck; it occasionally became generalized (ie, erythroderma). The eruption resolved with desquamation within 48 to 72 hours after cessation of infusion of IL-2. Histologically, the changes were not specific. The only consistent immunohistological finding noted was the presence of DR+/Leu-4+ lymphoid cells surrounding blood vessels in the papillary dermis, with fewer of these cells in the epidermis. There was no difference between the clinical or histological features of the eruption that occurred with IL-2 alone and that which occurred with IL-2 and lymphokine-activated killer cell infusion, suggesting that the cutaneous effects were mediated by IL-2 alone.  相似文献   
16.
Prolonged physical exercise is associated with multiple changes in blood hemostasis. Eccentric muscle activation induces microtrauma of skeletal muscles, inducing an inflammatory response. Since there is a link between inflammation and coagulation we speculated that downhill running strongly activates the coagulation system. Thirteen volunteers participated in the Tyrolean Speed Marathon (42,195 m downhill race, 795 m vertical distance). Venous blood was collected 3 days (T1) and 3 h (T2) before the run, within 30 min after finishing (T3) and 1 day thereafter (T4). We measured the following key parameters: creatine kinase, myoglobin, thrombin-antithrombin complex, prothrombin fragment F1 + 2, D-dimer, plasmin-alpha(2)-antiplasmin complexes, tissue-type plasminogen activator antigen, plasminogen-activator-inhibitor-1 antigen and thrombelastography with ROTEM [intrinsic pathway (InTEM) clotting time, clot formation time, maximum clot firmness, alpha angle]. Thrombin generation was evaluated by the Thrombin Dynamic Test and the Technothrombin TGA test. Creatine kinase and myoglobin were elevated at T3 and further increased at T4. Thrombin-antithrombin complex, prothrombin fragment F1 + 2, D-dimer, plasmin-alpha(2)-antiplasmin complexes, tissue-type plasminogen activator antigen and plasminogen-activator-inhibitor-1 antigen were significantly increased at T3. ROTEM analysis exhibited a shortening of InTEM clotting time and clot formation time after the marathon, and an increase in InTEM maximum clot firmness and alpha angle. Changes in TGA were indicative for thrombin generation after the marathon. We demonstrated that a downhill marathon induces an activation of coagulation, as measured by specific parameters for coagulation, ROTEM and thrombin generation assays. These changes were paralleled by an activation of fibrinolysis indicating a preserved hemostatic balance.  相似文献   
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The CXCL12/CXCR4 chemokine axis is a well characterized and important chemotactic stimulus/receptor unit that orchestrates the homing and migration of cells to the bone marrow and to ischemic tissues following tissue damage. Here, we demonstrate that the sialomucin, CD164, a regulator of haemopoietic precursor cell adhesion to stroma and entry of primitive CD34+CD38lo/‐ precursor cells into cycle, modulates the migration of CD133+ cord blood cells to CXCL12 by associating with the CXCR4 receptor. This was demonstrated by a reduction in CD133+ cell migration on fibronectin to CXCL12 (i) by engaging the functional class II glycosylation‐dependent epitope on CD164 with the 103B2/9E10 class II but not the N6B6 class III antibody; and (ii) by RNAi knockdown of CD164 protein levels in CD133+ cells. The inhibition of migration was more pronounced in the more primitive CD34+CD38lo/‐ cell subset. Similar studies using the Jurkat cell line confirmed these findings and led to further analyses using alternative chemokines. A direct association between CXCR4 and CD164 was demonstrated by the co‐localisation of CD164 with CXCR4 and VLA‐4 and VLA‐5 at the leading edge of CD133+ cells when CXCL12 was presented on fibronectin. This was further supported by immunoprecipitation studies that demonstrate in the absence of CXCL12, CXCR4 is associated only with VLA‐4 and VLA‐5 but on exposure to CXCL12, CD164 is rapidly recruited to the CXCR4 complex. Knock‐down of CD164 using siRNA revealed that signalling through CXCR4 via PKC‐ζ was significantly dampened. Our findings therefore support a novel association between three distinct families of cell surface receptors that regulate both cell migratory and proliferative responses and identify a CD164 as a key regulator of the CXCL12/CXCR4 axis.  相似文献   
19.
OBJECTIVE: To determine whether bacterial cultures of the wounds of patients undergoing clean orthopedic surgery would help predict infection. METHODS: During 1 year, 1,256 cultures were performed for 1,102 patients who underwent clean orthopedic surgery. Results were analyzed to evaluate their ability to predict postoperative infection. RESULTS: The sensitivity, specificity, positive predictive value, and negative predictive value of the cultures were 38%, 92%, 7%, and 99%, respectively. CONCLUSIONS: Cultures performed during clean orthopedic surgery were not useful for predicting postoperative infection.  相似文献   
20.
Cutaneous desensitization of the upper, rostral snout by bilateral section of the infraorbital nerves in lactating Norway rat dams markedly, but transiently, disrupted retrieval and licking of pups, nursing behavior, and fighting with a strange male intruder. Removal of the mystacial vibrissae, which provide major inputs to the infraorbital nerves, or cutaneous desensitization of the chin by bilateral sectioning of the mental nerves did not disrupt these behaviors. However, cutaneous desensitization of both the upper and lower rostral snout exacerbated and prolonged the effects produced by infraorbital denervation alone. The control of maternal behavior and aggression by somatosensory reflexes and the possible bases for rapid behavioral recovery after partial trigeminal sensory denervations are discussed.  相似文献   
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