Article abstract-Data from 694 patients hospitalized with stroke were entered in a prospective, computer-based registry. Three hundred and sixty-four patients (53 percent) were diagnosed as having thrombosis, 215 (31 percent) as having cerebral embolism, 70 (10 percent) as having intracerebral hematoma, and 45 (6 percent) a s having subarachnoid hemorrhage from aneurysm or arteriovenous malformations. The 364 patients diagnosed as having thrombosis were divided into 233 (34 percent of all 694 patients) whose thrombosis was thought to involve a large artery and 131 (19 percent) with lacunar infarction. Many of the findings in this study were comparable to those in previous registries based on postmortem data. New observations include the high incidence of lacunes and cerebral emboli, the absence of a n identifiable cardiac origin in 37 percent of all emboli, a nonsudden onset in 21 percent of emboli, and the occurrence of vomiting at onset in 51 percent and the absence of headache a t onset in 67 percent of hematomas.

A 5.7-year prospective study of 1380 patients treated for psoriasis with oral methoxsalen (8-methoxypsoralen) and ultraviolet A photochemotherapy (PUVA) revealed that after adjustment for exposures to ionizing radiation and topical tar preparations, the risk that cutaneous squamous-cell carcinoma would develop at least 22 months after the first exposure to PUVA was 12.8 times higher in patients exposed to a high dose than in those exposed to a low dose (95 per cent confidence interval, 5.8 to 28.5). No substantial dose-related increase was noted for basal-cell carcinoma. The dose-dependent risk of cutaneous squamous-cell carcinoma suggests that PUVA can act as an independent carcinogen. In our study, morbidity associated with these tumors has been limited, but further follow-up is needed. Meanwhile, patients treated with PUVA should be followed closely for the possible development of cutaneous squamous-cell carcinoma.

The National Library of Medicine's MEDLINE (MEDLARS Online) database was the first database to be searched nationwide via value-added telecommunication networks. Now available on the World Wide Web free of charge from the National Library of Medicine and from many other sources, it is the world's most heavily used medical database. MEDLINE is unique in that each reference to the medical literature is indexed under a controlled vocabulary called Medical Subject Headings (MeSH). These headings are the keys that unlock the medical literature. MeSH multiplies the usefulness of the MEDLINE database and makes it possible to search the medical literature as we do today. This paper commemorates the 40th anniversary of the introduction of MeSH and salutes some of the farsighted persons who conceived and developed the MEDLINE database.

Extensive psoriasis in 1,308 patients has been treated two or three times a week with oral 8-methoxypsoralen followed by high intensity, long-wave ultraviolet light (PUVA). Excluding 169 patients still under early treatment, psoriasis cleared in 88% and failed to clear in 3%. One percent dropped out due to complications of treatment, and 8% for other reasons. The twice-a-week schedule was superior for patients with lighter skin types. Once a remission was induced, there was no difference in its maintenance when patients were treated once a week, once every other week, or once every third week. Each of these schedules was superior to no maintenance treatment. Immediate side effect of the 45,000 treatments administered in the first 18 months of this study were uncommon, temporary, and generally mild. No clinically significant changes in laboratory screening or eye examinations attributable to PUVA have been uncovered.