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951.
Two hundred and thirty pregnancies were studied in 196 diabetic women. Seven women with babies found to have major malformations had a higher median first trimester haemoglobin A1 (12.9%) than the median HbA1 (10.8%) in those with normal babies (p = 0.06). No relationship was found between the occurrence of minor malformations and first trimester maternal haemoglobin A1. Two of the seven congenital malformations were diagnosed antenatally at a time when therapeutic abortion could be offered. Expert antenatal ultrasound scanning should be offered to all pregnant diabetic women as poor glycaemic control at the time of conception and organogenesis, as evidenced by raised first trimester HbA1, predisposes to congenital malformation.  相似文献   
952.
Lymphangitis carcinomatosis has a grave prognosis. We report a case from carcinoma of the breast that responded completely and durably to chemotherapy.  相似文献   
953.
954.
The effect of long-term treatment with the calcium antagonist nisoldipine on development of hypertension, cardiac hypertrophy, and plasma levels of atrial natriuretic peptides (ANP) was determined in spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY) of the same age. Measurement of immunoreactive ANP in plasma provided a sensitive marker for the severity of hypertension and the associated cardiac overload. Long-term treatment with nisoldipine prevented the development of hypertension, the associated heart failure, and the increase of plasma levels of ANP in SHR but had no effect on systolic blood pressure, heart weight, and plasma levels of ANP in WKY. In addition, nisoldipine had a therapeutic effect in old SHR with manifest cardiac failure in end-stage hypertension, as evidenced not only by the reduction of blood pressure but also by the reduction of cardiac hypertrophy, of elevated immunoreactive ANP in plasma, and of increased plasma renin activity.  相似文献   
955.
956.
Hirschsprung's disease in young adults   总被引:3,自引:0,他引:3  
Hirschsprung's disease is rarely seen in the young adult, and presents unique problems in management because of the massive dilatation and hypertrophy that occur proximal to the aganglionic rectum or the rectosigmoid colon. The diagnosis, which may be suspected by barium enema, is confirmed by suction or full-thickness biopsy of the rectum that may be complemented by anal manometry. Based on our experience with eight patients, a two-stage surgical reconstruction is recommended, with a preliminary sigmoid colostomy through the normally innervated colon and an associated defunctionalized stoma constituting the initial operation. The distal colonic stoma permits cleansing of the caudal colon while the normally innervated proximal colon reverts to near normal caliber, usually within 2 to 6 months. This approach is in accord with the recommendation of Fairgrieve. Reconstruction using a Duhamel or Soave procedure has given good results. The Duhamel procedure seems preferable when a considerable discrepancy remains between the ganglionic and aganglionic segments of rectum.  相似文献   
957.
958.
We examined several possible causes for the high incidence of poor sensory acuity in the limbs of 176 patients with moderate to severe peripheral vascular insufficiency. We investigated the relationships of diabetes, alcoholism, and smoking, as well as the severity of peripheral vascular disease, to the integrity of basic sensory modalities such as two-point discrimination and perception of light touch. The presence or absence of diabetes exerted the strongest effect on peripheral sensation. In patients who did not have diabetes, sensation in the limbs was most strongly affected by whether the patient was an alcoholic. Smoking did not have a significant effect on limb sensation. Among nondiabetic, nonalcoholic patients, there was a weak residual effect related to the severity of the peripheral vascular insufficiency. Even among these patients, however, systemic factors predominated in determining the loss of sensation. We also examined the extent to which loss of sensation might be related to the development of ulcers. Among patients who were not diabetic, there was a highly significant relationship between loss of sensation and the presence of limb ulceration. Surprisingly, however, there was no discernable relationship between the presence of ulcers in diabetic patients and the degree of loss of peripheral sensation. This result suggests that a large percentage of ulcers seen in diabetic patients are not of neurogenic origin.  相似文献   
959.
A questionnaire survey of career choices was carried out among 112 medical graduates, after one year's internship (group I), during their National Youth Corps programme in Kaduna, Lagos, Cross River and Oyo states of Nigeria, and 365 final-year medical undergraduates (group 2) in the colleges of medicine in the corresponding states. A total of 13% in group I and 40% in group 2 were undecided as regards their first choice. Obstetrics and gynaecology was the most popular first choice in both groups. General practice ranked fifth among group I, but displaced surgery to rank second among group 2. The differences were statistically significant. A total of 41% of group I and 46% of group 2 preferred to work in a teaching hospital, reflecting the high preference for surgical specialties. Twenty-six per cent and 33.7% of respondents in groups 1 and 2 respectively wished to own their own practice or work in the private sector. General practice is a new specialty and its growth is supported by a national postgraduate training programme. A shift towards general practice is seen compared with previous studies of career preference among Nigerian medical graduates and students. This may be due to a changing balance of supply and demand in the medical work-force, or a better assessment of the nation's health problems and manpower needs.  相似文献   
960.
During continuous near-infrared optical monitoring of brain cortex and hindlimb skeletal muscles, anesthetized, ventilated cats were exposed either to progressive alveolar hypoxia, or to acute hemorrhage followed in some cases by resuscitation. Hypoxia decreased cytochrome a,a3 oxidation state in muscle more than in brain, while tissue blood volume increased in brain and decreased in muscle. At a PaO2 of 25 torr, cytochrome a,a3 oxidation level in the brain was sufficient to support EEG activity, but the cytochrome a,a,3 oxidation state in resting, innervated hindlimb muscle was near zero. Hemorrhagic hypotension invariably decreased cytochrome a,a3 oxidation state and tissue blood volume more in muscle than in brain, and muscle cytochrome a,a3 was completely reduced at about a 25-ml/kg blood loss. These observations, supported by noninvasively measured changes in near-infrared absorption in the tissues during serial intravascular injections of indocyanine green dye, indicate that different cytochrome responses to hypoxia and oligemia in muscle vs. brain tissue are attributable to different regional circulatory adjustments.  相似文献   
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