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Biomedical subjects

J M Morris

Publications and source records attributed to J M Morris.

At least 73 records · Page 4Linked to original sources
PubMed1982

Photoperiodicity and circannual levels of LH, FSH, and testosterone in normal and castrated male, white-tailed deer.

To establish the relation between photoperiodicity and the levels of LH, FSH, and testosterone (T) in plasma, three intact and three castrated adult male white-tailed deer were sampled once a month for 2-3 years. The rang of average LH levels in controls varied between 0.8 and 2.0 ng/mL; the levels in castrates were considerably higher, 3.4 to 8.9 ng/mL. Average levels of FSH varied in controls between 25 and 112 ng/mL and in castrates between 141 and 240 ng/mL. A significant correlation between the seasonal time course of LH and FSH was found in castrated, but not in intact bucks. In castrates both gonadotropins exhibit two major elevations coinciding with spring and fall equinoxes in March and September. The seasonal time course of FSH in castrates correlates highly with seasonal levels of FSH in controls. However, the time course of the LH curve in controls is substantially different from the curve in castrates, presumably owing to feedback mechanisms. A possible role of testicular estradiol in this feedback is discussed. In controls, peak T levels are reached in December, i.e., 3 months after maximum levels of FSH and 5 months after peak levels of LH were detected. It appears that male deer undergo two periods of reproductive stimulation (one in the spring, the other in the fall). However, the organism responds with the full range of gonadal and behavioral mechanisms leading to the initiation of the rut only during the fall.

Animals↗
PubMed1979

The semiconstrained total shoulder arthroplasty.

In a two-year follow-up on sixteen total shoulder arthroplasties done with the semiconstrained Stanmore prosthesis, we found that patients with rheumatoid arthritis or osteoarthritis of the glenohumeral joint noted a greater relief of pain, were more satisfied with their surgery, used fewer analgesics, and had a greater increase in range of motion than patients with traumatic arthritis. Patients with irreparable rotator-cuff injury demonstrated the poorest range of motion postoperatively. Younger patients gained significantly more motion than older patients. All patients continued to have difficulty with lifting heavy loads. Complications consisted of one patient with a chronically dislocating prosthesis, one patient with a deep wound infection, and one with a postoperative wound dehiscence. The average follow-up was 31.4 months, ranging from twenty-four to fifty-three months.

Adult↗
PubMed1978

Nonexponential fluorescence decay of aqueous tryptophan and two related peptides by picosecond spectroscopy.

Time-resolved fluorescence spectroscopy of tryptophan and two related dipeptides, tryptophylalanine and alanyltryptophan, has been carried out on the subnanosecond time scale by using picosecond exciting pulses at a wavelength of 264 nm. Detection was with an ultrafast streak camera coupled to an optical multichannel analyzer. The zwitterions of these molecules show a definite nonexponential fluorescence decay which can be analyzed in terms of two exponentials. The two decay rates increase strongly with increasing temperature, as does the weight of the faster component. In tryptophan at pH 11, where the amino group is deprotonated, there remains only a single temperature-dependent exponential. The results are interpreted in terms of two kinds of trapped conformers in the excited state that interconvert no quicker than the time scale of the fluorescence. A model is suggested in which the nonradiative processes in one conformer approximate those in the bare indole moiety. The nonradiative decay rate of the other conformer is substantially faster. It is believed that the process responsible for this fast decay is intramolecular electron transfer from the indole to the amino acid side chain. The predilection for this electron transfer depends on steric relationships as well as on the electron-attracting power of the carbonyl group. This picture is consistent with earlier fluorescence quantum yield results. In fact, a self-consistent picture emerges from the temporal and yield data that quantitatively explains most important facets of tryptophan photochemistry in aqueous solution.

Journal Article↗
PubMed1978

Complications of water-soluble contrast lumbar myelography. Review of the literature and case report.

A historic review of the development of water-soluble contrast materials for lumbar myelography is presented. This is followed by a discussion of their advantages and complications, as well as a case report of convulsive segmental myoclonus, hypotension, and death after myelography associated with the use of dimeglumine locarmate (Dimer-X). A new nonionic material, metrizamide (Amipaque), is discussed, and its current clinical status is summarized.

Aged↗
PubMed1977

A pneumatically driven pump for constant perfusion manometry.

Syringe pumps are almost universally used for constant perfusion oesophageal manometry, despite important technical limitations. A pneumatically driven perfusion pump has been designed specifically for oesophageal manometry. This pump requires less than one third the flow setting of a syringe pump to achieve a given rate of pressure rise. It is simple to operate and needs infrequent refilling. Nearly two years' practical experience with this pump has confirmed its superiority over the syringe pump for constant perfusion manometry.

Air Pressure↗
PubMed1977

A formula for selective lymphadenectomy. Its application to cancer of the vulva.

A statistical formula can be applied to aid clinical judgment in decisions regarding the advisability of lymphadenectomy in gynecologic cancer. If benefit (B) factors in a given case do not exceed debit (D) factors, the procedure is ill-advised. In unilateral vulvar cancer, for example, if the ipsilateral inguinal nodes are negative, the risks from routine contralateral or deep pelvic node dissection appear to exceed the benefits.

Adult↗
PubMed1975

Routine use of hysterography in endometrial carcinoma and postmenopausal bleeding.

Unexpected hysterographic findings were encountered in 42 of 105 patients with postmenopausal bleeding or endometrial carcinoma. These included the extent and location of tumor, size and position of the uterus, uterine perforations or fistulas, and undetected myomas, congenital defects, or adnexal pathology. The findings proved of sufficient value in clinical management that hysterography, using water soluble medium, has been adopted as a routine procedure in such cases, especially if radium or cesium packing is employed. There was no statistically significant correlation between the histologic grade of the tumor and the hysterographic appearance of well-circumscribed or diffusely infiltrating lesions. Intravasation of contrast media occurred in 9 patients, lymphatic uptake was observed in 8, and peritoneal spillage of dye in 31 patients. There was no significant morbidity, and results to date show no evidence of tumor spread from the procedure.

Adenocarcinoma↗