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371.
Background. Cross-linked hyaluronic acid gels may offer longer-lasting cosmetic correction and a lower risk of immunogenicity than other soft tissue augmentation agents.
Objective. To compare the efficacy and safety of a non–animal-stabilized hyaluronic acid gel (Restylane Perlane, Q-Med, Uppsala, Sweden) with that of a hylan B gel (Hylaform, Genzyme Corp., Cambridge, MA, USA), a cross-linked hyaluronic acid from chicken combs, for treatment of nasolabial folds.
Methods. One hundred fifty patients with moderate or severe nasolabial folds were randomized to contralateral treatment with Restylane Perlane and Hylaform. Efficacy was assessed using semiobjective outcome instruments at 3, 4.5, and 6 months after achievement of an "optimal cosmetic result." Patients subsequently underwent open-label bilateral retreatment with Restylane Perlane (if required) and were followed up for a further 6 months.
Results. The two products were equally effective in producing an optimal cosmetic result, although fewer treatment sessions were required with Restylane Perlane. At 6 months post-treatment, a higher proportion of patients showed a ≥ 1-grade improvement in Wrinkle Severity Rating Scale (WSRS) score with Restylane Perlane (75%) than with Hylaform (38%). Restylane Perlane was considered superior in 64% of patients, whereas Hylaform was superior in 8% of patients.
Treatment-related adverse events tended to be more frequent with Restylane Perlane. Local injection-site reactions were generally transient and mild or moderate in intensity and were no more frequent after Restylane Perlane retreatment.
Conclusions. Restylane Perlane provides a more durable esthetic improvement than Hylaform and offers acceptable tolerability.  相似文献   
372.
Gellan gum beads containing cephalexin were prepared by extruding the dispersion of cephalexin and gellan gum into a solution containing a mixture of calcium and zinc ions (counterions). Beads were prepared by changing experimental variables such as pH of the counterion solution and amount of cephalexin loading in order to optimize process variables on the final % drug entrapment efficiency, release rates, size, and morphology of the beads. Absence of chemical interactions between drug, anionic polymer, and counterions after production of beads was confirmed by Fourier transform infrared spectroscopy. Differential scanning calorimetry was used to understand the crystalline nature of the drug after its successful entrapment. These data indicated the amorphous dispersion of cephalexin in the polymer matrix. Beads were spherical in shape, with the average bead size ranging from 925 to 1183 microm as measured by the laser light scattering technique. Cephalexin entrapment of up to 69.24% was achieved. In vitro release studies were performed in 0.1 N HCl or pH 7.4 phosphate buffer and the release of cephalexin was achieved up to 6 h. Dynamic swelling studies were performed in 0.1 N HCl or pH 7.4 phosphate buffer. Diffusion coefficients were calculated for spherical geometry. The release data have been fitted to an empirical relation to estimate the transport parameters. Mathematical modeling studies were performed for spherical geometry by solving Fick's equation to compute concentration profiles. These results were correlated with the release profiles.  相似文献   
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Eight cases discussed by experts at the 2007 Annual Scientific Meeting of the British Society of Haematology are presented as at the meeting, with a discussion of the morphological features, digital information and differential diagnosis being followed by further information and a final diagnosis. Additionally, digital slides of two of the cases were available to be viewed by the internet with the opportunity for delegates to suggest diagnoses.  相似文献   
376.
Cicatrizing conjunctivitis constitutes a group of chronic local and systemic disorders that cause conjunctival scarring. A systematic approach is required to sift through the clinical history, examination, and laboratory investigations of patients to arrive at the correct diagnosis of the underlying cause. Establishing the etiology is critical, as the therapeutic approach changes based on the cause of conjunctival inflammation. Effective management of patients with the condition requires knowledge of multiple modalities such as systemic immunosuppressive therapy, use of scleral contact lenses, and surgery for ocular surface and vision improvement. We review the clinical features of this condition and present diagnostic and treatment algorithms to help simplify the complexities in its management. This review attempts to place all the relevant information on chronic cicatrizing conjunctivitis together in one place for the benefit of cornea and ocular surface specialists, general ophthalmologists, and ophthalmology residents.  相似文献   
377.
Parasitology Research - People suffering from malnutrition become susceptible to the infection like Leishmania sp., as it results in a compromised immune response. Retinoic acid (RA), an important...  相似文献   
378.

Purpose

Existing studies on laxatives, used by roughly 40% of the U.S. population experiencing constipation and colorectal cancer (CRC) have yielded inconsistent results, which may be due to a failure to account for differential risks by major laxative types: bulk (fiber-based), and nonbulk (or nonfiber-based).

Methods

We examined the association of nonfiber-based laxative use and fiber-based laxative use with the risk of CRC in a subset of the multisite, International Colon Cancer Family Registry cohort comprising 4930 primary invasive CRC cases and 4025 controls selected from the general population. Epidemiologic risk factor questionnaires were administered to all participants at recruitment, and exposures were ascertained approximately 1 year before diagnosis for cases and at a comparable period for controls. We ascertained known and suspected CRC risk factors, including regular laxative use, which was defined as laxative intake at least twice a week for more than a month. Multivariable logistic regression models were used to estimate the adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs).

Results

Individuals who reported using nonfiber-based laxatives regularly were at a significantly increased risk for CRC compared with those who reported no laxative use (OR = 2.17, 95% CI = 1.47–3.19). No statistically significant associations were observed between fiber-based laxative use and CRC (OR = 0.99, 95% CI = 0.80–1.22).

Conclusions

Compared with nonusers, the risk of CRC increased with nonfiber-based laxative use, whereas CRC risk was not significantly associated with fiber-based laxative use.  相似文献   
379.
ObjectiveTo evaluate microscopy, OptiMAL® and multiplex PCR for the identification of Plasmodium falciparumm (P. falciparum) and Plasmodium vivax (P. vivax) from the field isolates of Bikaner, Rajasthan (Northwest India).MethodsIn this study, a multiplex PCR (P. falciparum and P. vivax) was further developed with the incorporation of Plasmodium malariae (P. malariae) specific primer and also a positive control. The performance of microscopy, plasmodium lactate dehydrogenase (pLDH) based malaria rapid diagnostic test OptiMAL® and 18S rRNA gene based multiplex PCR for the diagnosis of P. falciparum and P. vivax was compared.ResultsThe three species multiplex PCR (P. falciparum, P. vivax and P. malariae) with an inbuilt positive control was developed and evaluated. In comparison with multiplex PCR, which showed the sensitivity and specificity of 99.36% (95% CI, 98.11%–100.00%) and 100.00% (95% CI, 100.00%–100.00%), the sensitivity and specificity of microscopy was 90.44% (95% CI, 88.84%–95.04%) and 99.22% (95% CI, 97.71%–100.00%), and OptiMAL® was 93.58% (95% CI, 89.75%–97.42%) and 97.69% (95% CI, 95.10%–100.00%). The efficiencies were 99.65%, 95.10% and 95.45% for multiplex PCR, microscopy and OptiMAL®, respectively.ConclusionsOur results raise concerns over the overall sensitivities of microscopy and OptiMAL®, when compared to the multiplex PCR and thus stress the need for new molecular interventions in the accurate detection of the malarial parasites. This further highlights the fact that further developments are needed to improve the performance of rapid diagnostic tests at field level.  相似文献   
380.
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