PubMed Health⌕ Search

Biomedical subjects

S Cohen

Publications and source records attributed to S Cohen.

At least 1,045 records · Page 58Linked to original sources
PubMed1978

Altered lower esophageal sphincter function during early pregnancy.

To determine whether lower esophageal sphincter (LES) function was normal during early pregnancy, studies were performed in 8 pregnant women before and after abortion. Resting LES pressures were 22.1 +/- 2.4 and 22.6 +/- 2.3 mm Hg before and after abortion, respectively. During early pregnancy the LES pressure responses to pentagastrin were inhibited significantly. The LES responses to edrophonium and methacholine were decreased also. Finally, LES pressure responses to a protein meal were diminished in an additional 5 pregnant women. Serum concentrations of estrogen and progesterone were elevated during pregnancy, but the serum concentration of gastrin was unchanged. It can be concluded that in early pregnancy the basal LES pressure was within normal limits, but the LES pressure responses to hormonal, pharmacological and physiological stimulation were reduced (during demonstrated elevations of serum concentrations of estrogen and progesterone). These studies suggest that during early pregnancy, when no clinical symptoms of reflux are present, altered LES function may be demonstrated.

Abortion, Induced↗
PubMed1978

Tumor immunity.

Explore the source record for details and available documents.

Aging↗
PubMed1978

The pathophysiology and treatment of gastroesophageal reflux disease: new concepts.

In summary, the recent understanding of the pathogenesis of gastroesophageal reflux disease as owing to LES incompetence has led to improvement in both the diagnosis and the treatment of this disorder. Diagnosis now dependent on demonstrating the presence of reflux, an incompetent sphincter mechanism, or some complication of reflux. Treatment is focused on reducing the endogenous factors that contribute to reflux, or actually restoring the sphincteral barrier to reflux by pharmacologic or surgical means.

Bethanechol Compounds↗
PubMed1978

Inhibition of migration of tumor cells in vitro by lymphokine-containing supernatants.

Lymphokine-containing supernatants derived from seven different human lymphoid cell lines and lymphokine-containing supernatants from concanavalin A-stimulated murine lymphocytes were found to be capable of reversibly inhibiting the migration of tumor cells in vitro. The tumor cell lines used in these studies were the P815 mastocytoma, Ehrlich ascites, Walker carcinosarcoma, Hepatoma 129, and Sarcoma 37. Preliminary physiochemical evidence suggests that the mediator, here termed TMIF, is distinct from MIF. In any case, these results suggest the possibility that lymphokines other than lymphotoxin or macrophage-activating factors may play a role in tumor immunity.

Animals↗
PubMed1977

Angel dust.

Explore the source record for details and available documents.

Behavior↗
PubMed1977

Gastrointestinal myoelectrical activity in idiopathic intestinal pseudo-obstruction.

We evaluated the myoelectrical and motor function of the esophagus, small intestine, colon and anal sphincter in four patients with chronic idiopathic intestinal pseudo-obstruction. All patients had aperistalsis of the esophagus, with incomplete relaxation of the lower esophageal sphincter after swallowing or balloon distension. Duodenal slow-wave frequency was normal at 11.4+/-0.3 (+/-S.E.M.) cycles per minute. The patients did not have a normal increase in duodenal spike or motor activity after intestinal distension, but duodenal activity increased after stimulation with intravenous secretin. Colonic slow-wave activities were present at two frequencies, 6.2+/-0.3 and 3.3+/-0.1 cycles per minute. Neostigmine administration increased both colonic spike and motor activity normally. These studies suggest that in this disorder, physiologic neural responses to swallowing or intestinal distension are impaired but the intestinal smooth-muscle slow-wave activity and the spike and motor responses to exogenous neurohormonal stimulation are intact.

Adult↗
PubMed1977

Merozoite vaccination of douroucouli monkeys against falciparum malaria.

Erythrocytic merozoites of Plasmodium falciparum (Gambia) were isolated from cultures of schizont-infected human red cells on CF 11 cellulose columns. Douroucouli monkeys vaccinated with such preparations stored in liquid nitrogen and then emulsified in Freund's complete adjuvant (F.C.A.), were resistant to successive challenges with West African (Lagos) and East African (Uganda Palto-Alto) strains of P. falciparum. The induced immunity is specific since vaccination with P. knowlesi merozoites in F.C.A. does not modify the course of P. falciparum infections in douroucouli monkeys.

Animals↗
PubMed1977

Prevention by drugs of tachyphylaxis at nicotinic receptors in the cat superior cervical ganglion in situ.

A new compound, AF3 (4-ethyl-6-oxa-1-azatricyclo)4.2.2.02,7)dodecan-5-one), and its 4-phenyl analogue, AF6, embodying the structural elements of acetylcholine in a highly rigid framework, were shown to evoke nicotine-like responses in the nictitating membrane (NM) and blood pressure when applied to the superior cervical ganglion in anaesthetized cats. In this respect, their equiactive molar ratio was (nicotine : 1),20-30. However, at doses that were too low to evoke any response, AF3 appeared to potentiate the responses to nicotine or tetra-methylammonium (TMA) by preventing or abolishing tachyphylaxis to the two latter drugs, the effect being dose-dependent with AF3. DMPP which produces much less tachyphylaxis, or preganglionic nerve stimulation, was little or not potentiated in presence of AF3. It is proposed that potentiation to nicotine or TMA occurs following occupancy by AF3 of a regulatory subsite, thereby preventing further access to it by nicotine or TMA. In this respect, AF3 plays the role of a "neutral" molecule.

Animals↗