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The system of CH3I adsorbed on submonolayer, monolayer, and multilayer thin films of D2O on Cu(110) has been studied by measuring the time of flight (TOF) distributions of the desorbing CH3 fragments after photodissociation using linearly polarized λ = 248 nm light. For multilayer D2O films (2-120 ML), the photodissociation is dominated by neutral photodissociation via the 'A-band' absorption of CH3I. The polarization and angle dependent variation in the observed TOF spectra of the CH3 photofragments find that dissociation is largely via the 3Q0 excited state, but that also a contribution via the 1Q1 excitation can be identified. The photodissociation results also indicate that the CH3I adsorbed on D2O forms close-packed islands at submonolayer coverages, with a mixture of C-I bond axis orientations. For monolayer and submonolayer quantities of D2O we have observed a contribution to CH3I photodissociation via dissociative electron attachment (DEA) by photoelectrons. The observed DEA is consistent with delocalized photoelectrons from the substrate causing the observed dissociation- we do not find evidence for an enhanced DEA mechanism via the temporary solvation of photoelectrons in localized states of the D2O ice. [ABSTRACT FROM AUTHOR]

Electrocardiographic (ECG) recordings from 3 placebo-controlled thorough QT healthy volunteer studies were used to compare QT intervals obtained by manual measurement with those generated by ECG machines. The effect of the positive control was compared to placebo at each time point for data obtained from both sources. Both manual and automated techniques consistently demonstrated statistically significant prolongation of QTcF with the positive controls. The proportion of outlier values was small for both methods. The pairwise comparison between manual and automated uncorrected QT intervals demonstrated clear differences, with intervals derived from one machine on average 16 to 19 milliseconds shorter and from the other 7 milliseconds longer than the manually measured QT intervals, but these differences disappeared when analyzing QT change from baseline. Both manual and automated, commercially available QT algorithms demonstrated small statistically significant effects on the QTc interval induced by positive controls. [ABSTRACT FROM AUTHOR]

Many adult patients suffer from insomnia at least once a week. This quick overview of available drug therapies can help you offer them a good night's sleep. [ABSTRACT FROM AUTHOR]

Sunscreens protect against skin damage caused by the sun and should be used by most people throughout their lives. Do not let recent debate over the value of sunscreens deter you from recommending them. [ABSTRACT FROM AUTHOR]

Attention to the sensibilities of patients from different cultures is key to successful substance abuse treatment. Avoid preconceived notions, and explore each patient's beliefs, values, and concerns. [ABSTRACT FROM AUTHOR]

Internet accessibility, coupled with rapidly improving technology, makes telemedicine increasingly practical. But reimbursement and regulatory issues pose major obstacles to more widespread use. [ABSTRACT FROM AUTHOR]

Rule out several other less likely causes of hip pain, and guide the patient's recovery once the diagnosis is certain. Prognosis depends on the underlying cause, body weight, and compliance with a stretching regimen. [ABSTRACT FROM AUTHOR]

This sign can be an important aid in the differential diagnosis of infectious disease and often is the sole indication of drug fever. [ABSTRACT FROM AUTHOR]

The biggest development in genetic testing is its growing accessibility outside research laboratories. As effective preventive therapies and treatments for early-stage cancer develop, the need for genetic testing for cancer will grow. [ABSTRACT FROM AUTHOR]

Stress tests are a valuable tool for detecting CAD and for assessing prognosis, functional capacity, and response to therapy in patients with known disease. Here's how to choose the one that's right for your patients. [ABSTRACT FROM AUTHOR]

1. Pharmacokinetics were studied in mouse, rat, rabbit, dog and man after single intravenous and or oral doses of sildenafil or [14C]-sildenafil (ViagraTM). 2. In man, absorption from the gastrointestinal tract was essentially complete. With the exception of male rat, Tmax occurred at 1h or less. Bioavailability was attenuated by presystemic hepatic metabomlism in all species. 3. The volume of distribution was similar in rodents and humans (1-2 l/kg) but was greater in dog (5.2 l/kg), due to lower plasma protein binding (84 versus 94-96% respectively). 4. High clearance was the principal determinant of short elimination half-lives in rodents (0.4-1.3 h), whereas moderate clearance in dog and man resulted in longer halflives (6.1 and 3.7 h respectively). Clearances were in agreement with in vitro metabolism rates by liver microsomes from the various species. 5. After single oral or intravenous doses of [14C]-sildenafil, the majority of radioactivity was excreted in the faeces of all species. No unchanged drug was detected in the excreta of man. 6. Five principal pathways of metabolism in all species were piperazine N -demethylation, pyrazole N-demethylation, loss of a two-carbon fragment from the piperazine ring (N, N-deethylation), oxidation of the piperazine ring and aliphatic hydroxylation. Additional metabolites arose through combinations of these pathways. 7. Sildenafil was the major component detected in human plasma. Following oral doses, AUC for the piperazine N-desmethyl and piperazine N, N-desethyl metabolites were 55 and 27% that of parent compound respectively. [ABSTRACT FROM AUTHOR]

While a number of skin conditions are more common among people in specific ethnic groups, others occur frequently in all populations but have a different appearance on darker or lighter skin. The differences and similarities will guide your management. [ABSTRACT FROM AUTHOR]

Many of your patients regularly use complementary and alternative medicine therapies. Others may try them, depending on the information you offer about the benefits these practices can provide. [ABSTRACT FROM AUTHOR]

The diagnosis of infective endocarditis remains difficult, as does the treatment of this uncommon but potentially deadly disease. Better diagnostic criteria have been developed in recent years, however, allowing for more effective therapy. [ABSTRACT FROM AUTHOR]

More and more patients use herbal medicines for a range of treatment and preventive purposes. But which ones are really supported by scientific studies? What can you say to patients who ask about the safety and efficacy of these products? [ABSTRACT FROM AUTHOR]

Research is growing in support of applications of various mind-body therapies, including the relaxation response, mindfulness meditation, and hypnosis, often used in conjunction with conventional therapy. It's easy to apply these techniques in your practice. [ABSTRACT FROM AUTHOR]

Diagnosis of this often-fatal disorder can be difficult. A solid strategy is needed to maximize diagnostic accuracy through examination, a review of the patient's history, and the judicious use of tests. [ABSTRACT FROM AUTHOR]

Some myths persist--among physicians and patients--about managing cholesterol levels. To overcome them, it helps to review the accumulated evidence from various large-scale treatment trials. [ABSTRACT FROM AUTHOR]

Techniques for diagnosing GABHS have expanded far beyond the traditional throat culture. How useful are rapid antigen tests and other new methods compared to culture, and what role do clinical scoring systems play in diagnosis? [ABSTRACT FROM AUTHOR]

This comprehensive overview explores sterilization options for men, including nonsurgical approaches under development. No-scalpel vasectomy is less traumatic, less invasive, and more appealing to many men than traditional vasectomy. [ABSTRACT FROM AUTHOR]

In this first part of a 2-article update on sterilization, the authors interpret a key long-term study's comparison of female sterilization methods with failure rates. Then they apply the study's lessons to patient counseling. [ABSTRACT FROM AUTHOR]