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91.
The aim of this study was to determine the regional control rate with concurrent chemoradiotherapy (CRT) based on pretreatment nodal size in mucosal head and neck squamous cell carcinoma (HNSCC) in patients who achieved a complete response (CR) at the primary site by 12 weeks post‐treatment. Between December 1997 and November 2003, 117 patients with node‐positive HNSCC were treated with concurrent CRT, with 108 (92%) achieving a CR at the primary site by 12 weeks. There were 93 males (86%), median age 55 (37–79) years and the most common primary site was the oropharynx (65%). Patients were divided into three subgroups: ≤3.0 cm 70 (65%), 3.1–6.0 cm 30 (28%) and ≥6.1 cm 8 (7%). All patients received concurrent platinum‐based chemotherapy and the median radiation dose was 70 Gy (60–72 Gy). The 3‐year regional control rate based on pretreatment nodal size was ≤3.0 cm 88% (95% confidence interval (CI) 78–94%), 3.1–6.0 cm 72% (95%CI 49–86%) and ≥6.1 cm 50% (95%CI 15–77%) (P = 0.001). The 3‐year regional control rate based on pre‐treatment nodal size was ≤3.0cm 88% (95%CI 78–94%), 3.1–6.0 cm 72% (95%CI 49–86%) and ≥6.1 cm 50% (95%CI 15–77%) (P = 0.001). These results provide a quantitative guide for the clinician as to the likelihood of regional control based on pretreatment nodal size following CRT in patients who achieve a CR at the primary site by 12 weeks post‐treatment.  相似文献   
92.
A questionnaire to determine patterns of neonatal red cell transfusion practice during 1985 was mailed to 2200 blood banks of American Association of Blood Banks (AABB) institutional members and children's hospitals. There were 915 responses (41.6%); 785 responses (86%) contained sufficient data for analysis. The majority (70.6%) of 785 responding hospitals were community/urban institutions. However, more highly specialized, pediatric hospitals were also represented by 92 university/tertiary-care hospitals (11.7% of respondents) and 29 children's hospitals (3.7% of respondents). Two-thirds of hospitals performed a major antiglobulin crossmatch (rather than an abbreviated one) before all neonatal red cell transfusions. The red cell preparation most frequently selected for small-volume transfusions was ABO and Rh group-specific red cell concentrates. When performing only large-volume exchange transfusions, 19.2 percent of hospitals used whole blood; all others prepared reconstituted units of red cells plus fresh-frozen plasma, a practice that frequently causes exposure to two donors per unit. Another practice likely leading to multiple donor exposure is the use of fresh-frozen plasma to adjust the hematocrit of red cell preparations to a predetermined value prior to a small-volume transfusion. Over one-half of hospitals adjusting hematocrits used plasma, presumably from one donor, to dilute packed red cells from another donor, a practice that has no apparent medical benefit. Most hospitals (63.4%) provided red cells with a reduced risk of transmitting cytomegalovirus; blood from seronegative donors was selected by 65 percent of hospitals. The majority of hospitals, including most of the community/urban hospitals, did not irradiate blood products before transfusion.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
93.

Aim

Compare the diagnostic accuracy of surgeon performed ultrasound to radiology performed ultrasound in children presenting with suspected appendicitis to a tertiary care pediatric hospital in Australia.

Methods

Children under 16 presenting to the emergency department of The Children's Hospital at Westmead were considered for the study. Patients with obvious signs of appendicitis not requiring ultrasound and those with established ultrasound diagnosis of appendicitis were excluded. Ultrasound was performed by a Pediatric Surgeon (SPU) after obtaining consent. The treating team was blinded to the results. Patient underwent formal ultrasound in radiology (RPU) and treatment was based on the formal report. SPU result was reviewed by a radiologist blinded to results of RPU. The results were compared.

Results

65 children underwent ultrasound. 35 were male. Median age was 10 (range3–15). Median weight was 36 kg (range 12.6–76.2 kg), z-score median 0.21 (? 1.83 to 2.74). Symptom duration ranged from few hours to 2?weeks but majority (45) had symptoms for less than 48?h. Prevalence of appendicitis was 45%. Thirty two underwent surgery. Negative appendicectomy rate was 9.4%. Thirty three did not have surgery. 8 represented but only one proceeded to appendicectomy. SPU was done earlier than RPU (median 12?h vs 14.15?h) p?=?0.088. Diagnostic accuracy using ROC did not reveal significant difference.

Conclusion

SPU can be performed earlier than RPU with reliable accuracy. Training surgical trainees will enable early diagnosis and management of appendicitis.  相似文献   
94.
The ability to store platelets beyond 24 hours requires a functionally closed system. This study tested the ability of a cell separator bowl seal system to resist penetration of microbial contamination under normal running conditions and under extreme environmental stress. Three test organisms, Micrococcus luteus, Serratia marcescens, and Staphylococcus epidermidis, were applied directly to the bowl at the edge of the seal or aerosolized and passed through the centrifuge chamber while the cell separator was run through a simulated platelet collection. A sterile, bacteriologic nutrient medium was perfused through the tubing set, thus simulating the flow of blood fractions. Following the procedure, the medium was examined for microbial growth. The concentration of aerosolized bacteria ranged from 5.2 x 10(1) to 3.9 x 10(3) colony-forming units (CFU) per mL, and the concentration of bacteria applied to the edge of the seal ranged from 1.9 x 10(5) to 2.8 x 10(9) CFU per mL. The positive control, direct inoculation of S. marcescens into the circulating medium (50 CFU/500 mL), resulted in recovery of the identical organism after 24 hours' incubation. No contamination of the system was detected in 40 experiments with aerosolized bacteria or in 32 experiments in which bacteria were applied directly to the seal. This study demonstrates that this sealed-bowl system resists microbial contamination.  相似文献   
95.
96.
Background: Older people including ex-servicemen (ESM) in India are left to fend for themselves due to nuclear family system. Most children are not staying with them due to reasons such as acquiring of education or employment at distant places. These factors, coupled with deteriorating health with advancing age, change in value system and attitude amongst children who give more importance to materialism, it was felt necessary to find modalities to empower and strengthen ESM by available methods of including progressive weight training, yoga and meditation.  相似文献   
97.
Prior research has identified a number of risk factors ranging from inadequate household sanitation to maternal characteristics as important determinants of child malnutrition and health in India. What is less known is the extent to which these individual‐level risk factors are geographically distributed. Assessing the geographic distribution, especially at multiple levels, matters as it can inform where, and at what level, interventions should be targeted. The three levels of significance in the Indian context are villages, districts, and states. Thus, the purpose of this paper was to (a) examine what proportion of the variation in 21 risk factors is attributable to villages, districts, and states in India and (b) elucidate the specific states where these risk factors are clustered within India. Using the fourth National Family Health Survey dataset, from 2015 to 2016, we found that the proportion of variation attributable to villages ranged from 14% to 63%, 10% to 29% for districts and 17% to 62% for states. Furthermore, we found that Bihar, Jharkhand, Madhya Pradesh, and Uttar Pradesh were in the highest risk quintile for more than 10 of the risk factors included in our study. This is an indication of geographic clustering of risk factors. The risk factors that are clustered in states such as Bihar, Jharkhand, Madhya Pradesh and Uttar Pradesh underscore the need for policies and interventions that address a broader set of child malnutrition determinants beyond those that are nutrition specific.  相似文献   
98.
Extracts prepared from tissue specimens of normal, non-tumourous human buccal mucosa, and cultured buccal epithelial cells and fibroblasts, exhibited O6-methylguanine-DNA methyltransferase (MGMT) activity by catalysing the repair of the premutagenic O6-methylguanine lesion in isolated DNA with rates of 0.2 to 0.3 pmol/mg protein. An SV40 T antigen-immortalized buccal epithelial cell line termed SVpgC2a and a buccal squamous carcinoma line termed SqCC/Y1, both of which lack normal tumour suppressor gene p53 function, exhibited about 50 and 10% of the MGMT activity of normal cells, respectively. The normal, experimentally transformed and tumourous buccal cell types showed MGMT mRNA levels which correlated with their respective levels of MGMT activity. Exposure of buccal cell cultures to various organic or water- based extracts of products related to the use of tobacco and betel quid, decreased both cell survival (measured by reduction of tetrazolium dye) and MGMT activity (measured subsequently to the exposures in cellular extracts). Organic extracts of bidi smoke condensate and betel leaf showed higher potency than those of tobacco and snuff. An aqueous snuff extract also decreased both parameters, whereas an aqueous areca nut extract was without effect. The well- established sulph-hydryl-reactive agent Hg2+, a corrosion product of dental amalgam, served as a positive control and decreased MGMT activity following treatment of cells within a range of 1-10 microM. Taken together, significant MGMT activities were demonstrated in buccal tissue specimens and in the major buccal mucosal cell types in vitro. Lower than normal MGMT activity in two transformed buccal epithelial cell lines correlated with decreased MGMT mRNA and lack of functional p53. Finally, in vitro experiments suggested the potential inhibition of buccal mucosal MGMT activity by complex mixtures present in the saliva of tobacco and betel nut chewers.   相似文献   
99.
100.

Background  

According to DSM-IV there are three subtypes of Attention-Deficit/Hyperactivity Disorder, namely: ADHD predominantly inattentive type (ADHD-PI), ADHD predominantly Hyperactive-Impulsive Type (ADHD-HI), and ADHD combined type (ADHD-C). These subtypes may represent distinct neurobehavioral disorders of childhood onset with separate etiologies. The diagnosis of ADHD is behaviorally based; therefore, investigations into its possible etiologies should be based in behavior. Animal models of ADHD demonstrate construct validity when they accurately reproduce elements of the etiology, biochemistry, symptoms, and treatment of the disorder. Spontaneously hypertensive rats (SHR) fulfill many of the validation criteria and compare well with clinical cases of ADHD-C. The present study describes a novel rat model of the predominantly inattentive subtype (ADHD-PI).  相似文献   
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