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Surveys made during 1972–75 of 113 potato crops (cvs. Pentland Dell and Pentland Crown) growing in sandy soils, mainly in north Yorkshire, showed that .the incidence of spraing caused by tobacco rattle virus tended to decline with an Increase in the number of barley crops .grown in the three years prior to potatoes. In five potato crops the incidence of spraing was not affected by varying weed control in the preening barley crop. Field trials during 1973–75 tested the effects of aldicarb, oxamyl, fenamiphos, carbofuran and phorate on the incidence of spraing in cvs. Pentland Dell, Pentland Crown and Pentland Hawk. All these chemicals except phorate decreased spraing, but aldicarb and oxamyl were the most effective. Broadcast applications followed by rotavation seemed more effective than in-furrow treatments. [ABSTRACT FROM AUTHOR]

Observations of soil populations of Ditylenchus dipsaci (Kühn) Filipjev were made in the north of England from 1963 to 1969. Samples were taken in spring and autumn or winter from the same 14 commercial fields where oat cultivars susceptible to D. dipsaci had been damaged previously by this pest, from field plots under different rotations and different weed control programmes and from microplots under different crop rotations. In fields and field plots growing cereals, populations generally increased during summer and decreased during winter. Large increases occurred when oats were grown. With swedes, potatoes and ley, slight reductions occurred during summer and larger reductions during winter. Seven of the 14 sites contained populations below detectable levels after 2-8 years without an oat crop; in the remainder, detectable numbers were still present 1-7 years after an oat crop. Field plots receiving no herbicide maintained larger soil populations of D. dipsaci. Approximately 40-60 per cent of oat plants were damaged in crops grown after one or two years' barley and about 20 per cent after three years' barley whether or not herbicides had been applied. In microplots kept weed free, three years of barley, grass, or barley) grass rotation, three or four years' fallow or three or four years' weeds reduced soil levels of D. dipsaci by 99-100 per cent. After all these rotations one oat crop increased the soil population to detectable levels and a second oat crop showed symptoms of damage. [ABSTRACT FROM AUTHOR]

Nasal septal abscesses are uncommon. Sixteen cases from the Massachusetts Eye and Ear Infirmary were reviewed retrospectively and are presented. The diagnosis, bacteriology, and pathophysiology are discussed. Immediate therapy is indicated to avoid cosmetic deformity or intracranial infection. Treatment is based on diagnostic needle aspiration, antibiotic coverage and surgical drainage. [ABSTRACT FROM AUTHOR]

The herpesvirus family is associated with sudden hearing loss syndrome and the evidence includes clinical findings (HV-Z), temporal bone studies (CMV and HV-Z), and serologic studies. The data presented demonstrate that herpes infections, in association with sudden viral hearing loss, occur as part of a multiple viral infection in 70% of instances. This feature is unique to the herpesvirus infections when compared to other neurotropic viral agents. The study also demonstrates that the variables of viral hearing loss, such as degree of hearing loss, percentage of recovery, or the incidence of vertigo are unaffected by the presence of herpesvirus infection. Mechanisms for inner ear injury may be influenced by temporary alterations in cellular immunity secondary to simultaneous viral infections as well as the native virulence of the infecting herpesvirus. [ABSTRACT FROM AUTHOR]

A diabetic subgroup identified from a base population who have experienced idiopathic sudden hearing loss (ISHL) has been studied. In order to assess the relationship between diabetes and ISHL, two non-diabetic control groups were formed, and a comparison of the audiological data between the diabetic and non-diabetic ISHL patient was made. Mean degree of hearing loss and recovery, as well as the mean hearing level of the contralateral ear were analyzed. No statistically significant differences were noted in the audiological pattern of ISHL in diabetics and controls. A similar incidence of recovery was noted for the two groups throughout the mid frequencies; however, diabetic ISHL patients fail to recover as well as in the high frequencies. Preliminary data, while not statistically significant, suggest an increased hearing loss in both the affected and unaffected ear of the older diabetic patient. [ABSTRACT FROM AUTHOR]

This paper contains a review of the gross pathology and histopathology of juvenile nasopharyngeal angiofibroma and a review of the theories of origin of this tumor. The relative merits of hormone therapy, carotid arteriography, external and interstitial radiation therapy, cryosurgery, and various surgical approaches are discussed. A plan for the management of these tumors has been developed: 1. Estrogen therapy is begun one month pre-operatively, if it is to be used. 2. The patient sees a prosthodontist so that he may have a temporary plastic plate made which will fit onto the teeth in such a manner that it will hold a transpalatal flap in place following surgery, without disturbing the suture line. 3. Arteriography is scheduled only if there is evidence of intracranial extension or an extensive recurrence. 4. Radon seeds, usually 10 in number and 1 me in size, are ordered for the day of surgery. 5. Liquid nitrogen is made ready for use with a closed cryo-probe system. 6. The expected blood loss and the possible use of planned hypotensive anesthesia are discussed with the anesthesiologist. An adequate supply of blood is to be available in the operating room at the start of the resection of tumor. 7. A plan is made for a transpalatal or transantral approach, or both, or occasionally for a lateral rhinotomy approach. Rarely has a transmandibular pterygoid approach been found necessary. The combined transpalatal-transantral approach is described in detail. Two. cases are presented. [ABSTRACT FROM AUTHOR]

Our experience with over 147 operations for pituitary disease has given us an opportunity to use and evaluate four separate transseptal approaches. Three approaches have been described previously in the literature: the sublabial transseptal, the open rhinoplasty, and the alotomy with anterior septal dissection. The fourth approach, alotomy with posterior septal dissection, is described here. The advantages and disadvantages of each are discussed, as are the complications of transseptal surgery. A working knowledge of the various transseptal approaches to the pituitary is imperative for the otolaryngologist who participates in pituitary surgery. [ABSTRACT FROM AUTHOR]

Objectives: This study uses a porcine model to establish the feasibility of performing endoscopic procedures in the neck using standard techniques currently being employed in preperitoneal endoscopy in the abdomen., Study Design: It is a pilot study presented as a case series., Methods: Ten animals were subjected to anterior deep cervical fascia dissection using standard endoscopic instrumentation., Results: Balloon dissection and CO2 insufflation poses a number of problems: CO2 gas dissection into the chest, CO2 gas embolism into the venous circulation, carotid artery occlusion, and limited visualization causing increased risk of injury to adjacent structures., Conclusion: These issues need to be dealt with before such a method could be employed safely in humans. However, with further research and development, endoscopic neck surgery may someday become a reality.

This study compared N-methyl-D-aspartate (NMDA)-stimulated increases in intracellular calcium in fura-2-loaded neurons dissociated from newborn rat brainstem (EC50 in microM; 6.4), cerebellum (9.5), forebrain (6.3), and hippocampus (10.6). Ethanol inhibition of the response to 25 microM NMDA differed among the regions. The NMDA response in hippocampus was inhibited by 20 mM ethanol; cortex and cerebellum responses were inhibited by 80 mM ethanol, and no inhibition was seen in the brainstem. Addition of glycine (15 microM) failed to attenuate ethanol inhibition of the NMDA response. These results demonstrate that ethanol inhibition of NMDA-stimulated responses varies according to brain region. In contrast to previous findings from this laboratory using dissociated neurons from whole brain, the addition of glycine did not reverse the inhibitory effects of ethanol on NMDA-stimulated responses.

1. Hypoxia arises in solid tumour because of inefficient blood supply. While hypoxic cells are resistant to radiotherapy and probably to many chemotherapeutic drugs they can, in principle, be turned to advantage through the development of hypoxia-activated cytotoxic drugs (bioreductive drugs). 2. Three general approaches to exploiting tumour hypoxia are discussed. The first relies on fluctuating blood flow in tumours and the consequent cycling of cells through the hypoxic compartment. The second incorporates a prodrug approach in which drug activation gives rise to cytotoxic metabolites which diffuse out of hypoxic zones. The third utilizes selective inhibitors of tumour blood flow to induce additional hypoxia and thus enhance bioreductive drug activation. 3. The latter two approaches are illustrated by recent studies with the dinitrobenzamide nitrogen mustard class of bioreductive drugs and their combination with the tumour blood flow inhibitor 5,6-dimethylxanthenone-4-acetic acid.