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91.
The aim of this prospective study was to determine the delay between the onset of symptoms and arrival in the coronary care unit of patients with suspected acute myocardial infarction, and the relative contribution to the total delay of patient delay, method of referral (self referral or general practitioner referral) and delay in the hospital before reaching the coronary care unit. All patients admitted with chest pain to the coronary care unit at Dudley Road Hospital, Birmingham, over the six month period April-September 1989 were included in the study. Ninety five patients were referred by their general practitioner and 107 patients attended the accident and emergency department directly or arrived by ambulance without contacting their general practitioner. The proportion of self referred and general practitioner referred patients with acute myocardial infarction, angina and non-cardiac chest pain were not significantly different. The total delay was significantly longer for patients who had been referred by their general practitioner (median 5.3 hours) than for self referrals (3.2 hours, P less than 0.001), with a significantly higher proportion of self referrals arriving at the coronary care unit within six hours of the onset of symptoms (77% versus 54%, P less than 0.01). Among general practitioner referrals, initial patient delay accounted for a median of 2.5 hours and the general practitioner's response time for a median of 1.1 hours. The delay in hospital was similar for both groups of patients. In inner city areas, self referral may result in considerably less delay than general practitioner referral allowing a greater proportion of patients to receive effective thrombolytic therapy.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
92.
93.
The differentiation of the urinogenital system and the appendicular skeleton in vertebrates is under the control of Hox genes. The common control of digit and gonad differentiation raises the possibility that patterns of digit formation may relate to spermatogenesis and hormonal concentrations. This work was concerned with the ratio between the length of the 2nd and 4th digit (2D:4D) in humans. We showed that (i) 2D:4D in right and left hands has a sexually dimorphic pattern; in males mean 2D:4D = 0.98, i.e. the 4th digit tended to be longer than the 2nd and in females mean 2D:4D = 1.00, i.e. the 2nd and 4th digits tended to be of equal length. The dimorphism is present from at least age 2 years and 2D:4D is probably established in utero; (ii) high 2D:4D ratio in right hands was associated with germ cell failure in men (P = 0.04); (iii) sperm number was negatively related to 2D:4D in the right hand (P = 0.004); (iv) in men testosterone concentrations were negatively related to right hand 2D:4D and in women and men LH (right hand), oestrogen (right and left hands) and prolactin (right hand) concentrations were positively correlated with 2D:4D ratio and (v) 2D:4D ratio in right hands remained positively related to luteinizing hormone and oestrogen after controlling for sex, age, height and weight.   相似文献   
94.
Rats were treated for 3 or 14 days with cyclosporin A (CsA, 50 mg/kg) or indomethacin (2 or 5 mg/kg) either alone or in combination, or with CsA plus 16,16-dimethylprostaglandin E2 (DMPGE2, 0.25 mg/kg). Hepatic and renal function were unaffected by treatment with indomethacin at either dose and only at the higher dose was severe intestinal ulceration observed. CsA caused renal and hepatic toxicity, evidenced by increased urine N-acetyl-beta-D-glucosaminidase activity, serum urea, creatinine and bilirubin and decreased serum albumin and total protein. In rats cotreated with CsA and either dose of indomethacin the increases in serum urea and creatinine and decreases in serum albumin and total protein were accentuated, but serum bilirubin was not further increased. Intestinal lesions were present in rats treated for 14 days with CsA plus the lower dose of indomethacin, but not in rats treated with either drug alone. In rats treated with DMPGE2 plus CsA, serum urea and creatinine were normal and urine N-acetyl-beta-D-glucosaminidase activity was reduced compared to rats treated with CsA alone, but DMPGE2 cotreatment had no effect on the CsA induced hyperbilirubinaemia. Hepatic microsomal cytochrome P-450 concentration and aminopyrine N-demethylase activity were lower in rats treated with CsA plus indomethacin than in untreated rats or those treated with either drug alone. Coadministration of indomethacin or DMPGE2 had no effect on serum trough CsA levels. The results are interpreted as showing an exacerbation by CsA of the intestinal toxicity of indomethacin, an increase by indomethacin in the renal toxicity of CsA and a protection by DMPGE2 against CsA renal toxicity. Possible mechanisms involving drug interactions and either hepatic cytochrome P-450, renal cyclooxygenase or other renal sites are discussed.  相似文献   
95.
96.
Tricho-dento-osseous syndrome (TDO), MIM# 190320, is transmitted as a highly penetrant autosomal dominant trait that is characterized by variable clinical expression. The principal clinical features include kinky/curly hair in infancy, enamel hypoplasia, taurodontism, as well as increased thickness and density of cranial bones. Possible genetic linkage has been reported for TDO with the ABO blood group locus, but the gene defect remains unknown. We have identified four multiplex families (n = 63, 39 affected, 24 unaffected) from North Carolina segregating TDO. We previously have excluded a major locus for TDO in the ABO region for these families. Utilizing a genome-wide search strategy, we obtained conclusive evidence for linkage of the TDO syndrome locus to markers on chromosome 17q21 (D17S791, Z max = 10.54, Theta = 0.00) with no indication of genetic heterogeneity. Multipoint analysis suggests the TDO locus is located in a 7 cM chromosomal segment flanked by D17S932 and D17S941. This finding represents the first step towards isolation and cloning of the TDO gene. Identification of this gene has important implications for understanding normal and abnormal craniofacial development of hair, teeth and bone.   相似文献   
97.
Production of chick interferon by reactivating chick erythrocytes   总被引:1,自引:0,他引:1  
When chick erythrocytes were fused with mouse L929 or A9 cells and the heterokaryons induced for interferon production on consecutive days, considerable amounts of mouse interferon were produced every day. Small amounts of chick interferon were produced 2 to 3 days after fusion, coincident with the appearance of a chick enzyme, appearance of nucleoli and increase in chick cell nuclear diameter.  相似文献   
98.
Lactate production in isolated perfused rat lung   总被引:1,自引:0,他引:1  
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99.
We present 3 adults with cardiac rhabdomyomas, 2 in the atria and 1 in the right ventricle. One atrial tumor was discovered incidentally, and 1 resulted in supraventricular tachycardia. The ventricular lesion caused ventricular tachycardia. Compared with congenital rhabdomyomas, the tumors are relatively cellular, the cells are smaller, there are few spider cells, and there is evidence of cell proliferation. Two of the 3 tumors demonstrated spindling in contrast to adult rhabdomyomas of the head and neck. Although surgical excision was possible in all patients, long-term follow-up will be required to determine the true biologic behavior of these neoplasms.  相似文献   
100.
A springtime olympics demands special consideration for allergic athletes   总被引:8,自引:0,他引:8  
BACKGROUND: The Sydney Olympic and Paralympic Games will be held in September-October 2000, which is early to mid-spring in the southern hemisphere. Pollen-sensitive athletes may encounter problems with allergic symptoms triggered by pollen exposure, thus compromising their ability to attain peak performance. OBJECTIVE: We sought to monitor pollen levels at the major Olympic venues to provide information for allergic athletes and their team doctors in order to adequately prepare them for Olympic competition. METHODS: We performed aerobiologic monitoring of the major Olympic venues to provide a profile of the most prevalent pollen species appearing during the spring. In the second part of this study, we surveyed a population of elite Australian athletes from Olympic sports to ascertain the prevalence of allergic rhinoconjunctivitis, to investigate the major allergens involved in sensitization, and to conduct a pilot study to assess the effect of allergic rhinoconjunctivitis on quality of life. RESULTS: The pollen counts obtained at the 3 major sites were high over the period of Olympic competition. Tree pollens appeared from July, and grasses appeared from early September and peaked in the second week of October, the beginning of Paralympic competition. A relatively small number of pollen varieties comprise the majority of the total pollen count. Two hundred fourteen athletes (61% male; mean age, 21 +/- 16 years) representing 12 Olympic sports participated in the study. Fifty-six percent gave a symptom history consistent with allergic rhinoconjunctivitis, 41% had symptoms of allergic rhinoconjunctivitis and a positive test response to any one allergen, and 29% had seasonal allergic rhinoconjunctivitis (a positive history and at least one positive skin prick test response to a seasonal allergen). Athletes from aquatic sports were more likely to have symptoms than those from other sports. Symptom scores were higher and quality of life ratings were poorer in allergic compared with nonallergic athletes over the spring period. CONCLUSION: Olympic team managers and medical officers need to adequately prepare Olympic athletes for the possibility of exposure to high pollen levels in the weeks leading up to this most important sporting event. Symptoms of pollen sensitivity, such as rhinoconjunctivitis and exacerbation of asthma, could be devastating to athletes expecting peak performance. Potential Olympic athletes should be screened for the possibility of pollen allergy and have medical programs with permitted medication tailored to meet their needs. This may involve preventative therapy with medication, such as intranasal corticosteroid sprays or immunotherapy programs, if symptoms are particularly severe. The newer nonsedating antihistamines are the treatment of choice for acute intermittent symptoms. Appropriate management will ensure that the allergic athlete will safely perform to maximum ability with permitted medication during the Spring 2000 Olympic Games in Sydney.  相似文献   
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