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The conductivity behaviour of carboxymethylcellulose (CMC) solutions was studied using different types of neutralizing reagents (LiOH, NaOH, KOH); the following order of conductance of CMC solutions was observed: Li+ < Na+ < K+. This conductance behaviour of CMC solutions with respect to the size of counterions is explained qualitatively as well as quantitatively. Binding of Li+, Na+ and K+ ions onto the polymer molecule and the influence of the degree of substitution, ,DS , on the conductivity of CMC were also investigated. The conductivity of CMC solutions as well as the fraction of bound counterions increase with increasing DS , at a given degree of neutralization (α) for each type of counterion. The effect of DS on the polymer charge fraction, i/s, is in line with the counterion condensation phenomena of Oosawa. The results regarding the dependence of the equivalent conductance of the polyion, Δp, on DS are compared with literature data.  相似文献   
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Sixty-three (5%) of 1239 women studied by sonography during the second trimester of their pregnancies had a diagnosis of placenta previa. Follow-up was available for 51 of the 63 patients; in three of these, the original diagnosis was complete placenta previa, and in the other 48, the first diagnosis was partial or marginal placenta previa. At term, placenta previa was seen in only four patients for an overall frequency of 0.3% (4/1227). In all three of the patients with complete placenta previa, the condition persisted from the second trimester to term; previa persisted in only one of 48 patients with marginal/partial previa. Because of the infrequent persistence of marginal or partial placenta previa to term, we recommend using the term "potential placenta previa" in the second trimester, with follow-up sonography indicated only for vaginal bleeding.  相似文献   
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BACKGROUNDPrevious studies have shown that non-surgical management can be an effective treatment strategy for many patients with rotator cuff tears. Despite the prevalence of rotator cuff disease, few studies have examined the patient and tear related factors that predict outcomes of nonsurgical management in this cohort of patients.AIMTo identify factors that are associated with changes in patient reported outcomes over time in individuals with full-thickness rotator cuff tears treated without surgery. METHODSA cohort of 59 patients who underwent non-surgical management of full thickness rotator cuff tears with a minimum of 1-year follow-up were identified from our institutional registry. Patient demographics, comorbidities and tear characteristics were collected at initial presentation. Outcome measures were collected at baseline and at each clinical follow-up, which included Western Ontario Rotator Cuff (WORC) index, American Shoulder and Elbow Surgeons score, Visual Analog Scale for pain and Single Assessment Numerical Evaluation. Multi- and univariate regression analyses were used to determine the impact of each patient and tear related variable on final WORC scores and change in WORC scores throughout the study. RESULTSIn this non-surgical cohort, all patient-reported outcome measures significantly improved compared to baseline at 1 and 2-year follow-up. There was no significant difference in outcomes between 1 and 2 years. The average improvement surpassed the published minimal clinically important differences values for WORC, American Shoulder and Elbow Surgeons, Visual Analog Scale pain and Single Assessment Numerical Evaluation scores. Regression analysis identified female gender (β = - 19.88, P = 0.003), smoking (β = -29.98, P = 0.014) and significant subscapularis fatty infiltration (β = -15.35, P = 0.024) as predictors of less favorable WORC scores at 1 year, and female gender (β = -19.09, P = 0.015) alone as a predictor of lower WORC scores at 2 years. Patients with symptom duration greater than 1 year at presentation reported less improvement in WORC scores at 1-year follow-up (β = -14.63, P = 0.052) and patients with traumatic tears reported greater improvements in WORC scores at 2-year follow-up (β = 17.37, P = 0.031). CONCLUSIONPatients with full thickness rotator cuff tears can achieve and maintain clinically meaningful benefit from non-surgical management through 2-year follow-up. Female patients, smokers, and those with significant subscapularis fatty infiltration tend to have lower overall WORC scores at 1-year follow-up, and females also have lower WORC scores at 2-year follow-up. Patients presenting with symptoms greater than 1 year had less clinical improvement at 1-year follow-up, and those with traumatic tears had greater clinical improvement at 2-year follow-up.  相似文献   
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IntroductionEx vivo fusion assays offer an efficient method for studying HIV-1 entry associated with contraceptive use and pregnancy outside of cohort studies of HIV-1 incidence.MethodsWe measured ex vivo HIV-1 fusion to cervical or endometrial immune cells from three groups of women: pregnant, non-pregnant not using hormonal or intrauterine contraception, and using depot medroxyprogesterone acetate (DMPA).Results and conclusionsThere was no excess susceptibility to HIV-1 fusion of cells from pregnant women or DMPA users compared to controls. Although the number of target cells in endometrium was higher in DMPA users compared to controls, HIV-1 fusion was lower.ImplicationsIn ex vivo assays, HIV-1 showed no enhanced fusion to cervical immune cells from pregnant women or DMPA users compared to controls, and lower fusion to endometrial immune cells from DMPA users. This assay is useful for studying hormonal and contraceptive effects on HIV-1 entry into reproductive tract immune cells.  相似文献   
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Seventy five patients of recurrent genital herpes (RGH) treated with oral or topical acyclovir and placebo were compared and followed for periods ranging 4 to 8 years in a prospective study. Oral acyclovir definitely helps RGH patients; it shortens healing time; postpones recurrences and instills confidence in the patients. There is sufficient evidence that RGH dies a natural death with time as seen after 8 years follow up in placebo group patients. Topical use of acyclovir cream is not as useful as believed.  相似文献   
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The aim of this retrospective study was to document the various causes of epilepsy determined by computed tomography (CT). We studied 205 CT scans carried out in patients with symptomatic epilepsy. We identified 52 (25.36%) pathological causes: 18 cases (34.62%) of infectious lesions, predominantly toxoplasmosis, 9 cases (17.30%) of tumors, 9 cases (17.30%) of vascular lesions and 8 cases (15.39%) of post-traumatic and atrophic lesions. CT is of great value in the diagnosis of epilepsy, not only in the assessment of the disease, but also for identifying the lesion responsible for the seizures, which may be treatable. It is advisable to carry out a CT scan for any patient presenting with symptomatic epilepsy.  相似文献   
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Background. Prevalence of type 2 or non insulin dependent diabetes mellitus is high among Indians living in India as well as abroad. Prevalence among persons of Indian origin in many countries is greater than that of people of other ethnic extraction. The Indian state of Kerala is distinguished by a high level of achievement in the health sector, characterised by both lower mortality rates and greater density of health care institutions that ensure access to most people. These attributes make the prevalence of diabetes and the pattern of its management in Kerala worth studying. Objective. To estimate the prevalence of diabetes among persons 20 years or older in an urban housing settlement in Trivandrum city, the capital of Kerala, as well as study the management of the disease in subjects affected. Design. Cross sectional survey for detecting diabetes and other chronic diseases in all willing residents of an urban housing settlement in Trivandrum, the capital city of Kerala, as part of a preventive campaign against lifestyle diseases. Fasting plasma glucose, serum triglycerides, cholesterol, height, weight and blood pressure were measured, and a detailed questionnaire administered to ascertain previous diabetic status and management. Results. Overall prevalence of type 2 diabetes is 16.3%. In the 30-64 age group, age standardised prevalence is 13.7%. Gender differences in prevalence are negligible. Greater prevalence is associated with advancing age, body mass index above 24.99, sedentary habits, serum total cholesterol > 239, serum triglycerides > 149, hypertension and smoking. Compared to non-diabetics, diabetics have greater mean and range of fasting plasma glucose values (8.87 + /-3.6 mM/l as against 4.34 + /-0.53 mM/l). 32 out of 38 diabetics among the subjects (82.4%) were already diagnosed even before the survey; of them, 89% were on medication. 3% of subjects had impaired fasting glucose, or FPG level between 110-125 mg/dl. Conclusion. Prevalence of type 2 diabetes among a group of urban residents in Trivandrum city in Kerala is very high. This is associated also with a high detection rate and compliance to treatment.  相似文献   
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