共轭方向法在HPLC流动相条件优化中的应用——麻黄碱、伪麻黄碱的分离

麻黄碱与伪麻黄碱是中药麻黄的主要有效成分,也是一对化学物理性质很相似的差向异构体。二者的结构只是构象不同,用色谱方法进行分离有一定的难度。目前已有在苯基和腈基键合固定相上进行HPLC分离的报道^(1,2)。本文成功地引入共轭方向法在μBondapak C₁₈色谱柱上对流动相组成进行了条件优化,优化后的色谱条件下麻黄碱与伪麻黄碱的分离情况令人满意。     

Quadrilateral space syndrome: a rare cause of shoulder pain

The authors report a case of quadrilateral space syndrome in a baseball pitcher. The diagnosis was made by means of subclavian arteriography performed with the arm in abduction and external rotation. This entity is a rare cause of shoulder pain caused by occlusion of the posterior humeral circumflex artery in the quadrilateral space.     

Immobilization hypercalcemia after single limb fractures in children and adolescents

Immobilization hypercalcemia following a single limb fracture of one weight bearing bone has been reported rarely in the pediatric age group. Nevertheless, in six of 12 patients immobilization hypercalcemia developed, associated with elevations in the urinary calcium/creatinine ratio and serum levels of ionized calcium after a single limb fracture of a weight-bearing bone during this two-year study period. We suggest that immobilization hypercalcemia occurs frequently in both children and adolescents after a single limb fracture of one weight-bearing bone, exercises in bed fail to prevent immobilization hypercalcemia, serial measurements of the serum ionized calcium and the urinary calcium/creatinine ratio are critical measures in treating such patients, and though complete mobilization is curative, transient calcitonin therapy is highly effective in reversing the disorders in calcium metabolism.     

Mucinous adenocarcinoma of the orbit arising from a stable, benign-appearing eyelid nodule

Mucinous adenocarcinoma is a rare eyelid tumor which should be considered in the differential diagnosis of a nodular or cystic lesion of the eyelid. This lesion may be locally aggressive and requires complete excision to prevent local recurrence or regional metastases. We present what we believe is the first report of a mucinous adenocarcinoma manifesting as a stable, benign-appearing nodule that has already given rise to a much larger secondary lesion. This case underscores the importance of performing a biopsy on even benign-appearing eyelid nodules.     

A prospective study of symptomatic bacteremia following platelet transfusion and of its management

BACKGROUND: The danger of bacteremia due to contaminated platelets is not well known. There are also no established guidelines for the management of febrile reactions after platelet transfusion. STUDY DESIGN AND METHODS: To determine the risk of symptomatic bacteremia after platelet transfusion, 3584 platelet transfusions given to 161 patients after bone marrow transplantation were prospectively studied. Platelet bags were routinely refrigerated for 24 hours after transfusion. Septic work-up was initiated for a temperature rise of more than 2 degrees C above the pretransfusion value within 24 hours of platelet transfusion or a temperature rise of more than 1 degree C that was associated with chills and rigor. Diagnosis of bacteremia after platelet transfusion was made only when the pairs of isolates from the blood and the platelet bags were identical with respect to their biochemical profile, antibiotic sensitivity, serotyping, or ribotyping. RESULTS: Thirty-seven febrile reactions, as defined above, occurred. Bacteremia subsequent to platelet transfusion was diagnosed in 10 cases. There was a 27-percent chance (95% CI, 15–43%) that these febrile reactions represented bacteremia that resulted from platelet transfusion. For a subgroup of 19 patients with a temperature rise of more than 2 degrees C, the risk of bacteremia was 42 percent (95% CI, 23–64%). Septic shock occurred in 4 of the 10 bacteremic patients. A rapid diagnosis was possible because the involved bacteria were demonstrated by direct Gram stain of the samples taken from the platelet bags of all 10 patients. CONCLUSION: Significant febrile reactions after platelet transfusion are highly likely to be indicative of bacteremia. Routine retention of platelet bags for subsequent microbiologic study was useful in the investigation of these febrile reactions. Empiric antibiotic therapy is indicated.     

差示分光光度法测定牛黄类中成药中胆红素的含量

本文利用胆红素溶液在光照下易氧化变色及其吸收光谱发生显著变化的性质,在波长453 nm处,测其光照前后的吸收度差值(△A),△A与胆红素溶液浓度呈线性关系,对含牛黄的中成药(六应丸,六神丸和牛黄消炎丸)中胆红素进行了定量,并对其它组分进行了光照试验,排除了光照对其它组分的影响,从而确定了此法的可行性。     

Suspected leaking abdominal aortic aneurysm: use of sonography in the emergency room

To determine the value of sonography in the emergent evaluation of suspected leaking abdominal aortic aneurysms, the authors examined 60 patients in the emergency department using sonography and a protocol involving advance radio notification from the ambulance; arrival of sonographic personnel and equipment in the triage room before patient arrival; and, during other triage activities, rapid sonographic evaluation of the aorta for aneurysm and of the paraaortic region for extraluminal blood. Sonographic findings were correlated with surgical results and clinical outcome. When performed under these circumstances, sonography was accurate in demonstrating presence or absence of aneurysm (98%), but its sensitivity for extraluminal blood was poor (4%). A combination of sonographic confirmation of aneurysm, abdominal pain, and unstable hemodynamic condition resulted in the correct decision to perform emergent surgery in 21 of 22 patients (95%). An abbreviated sonographic examination done in the emergency room can provide accurate, useful information about the presence of aneurysm; this procedure does not significantly delay triage of these patients.     

Alpha-thalassemia in two Mediterranean populations

We used restriction endonuclease analysis to determine the incidence of alpha-thalassemia in two Mediterranean islands. In a random population sample, the gene frequency of deletion-type alpha-thalassemia-2 (- alpha) was 0.18 in Sardinians and 0.07 in Greek Cypriots. All cases were the rightward crossover type. From these frequencies and the known incidence of hemoglobin-H disease in these populations, we calculated the frequency of the alpha-thalassemia-1 genotype (--) and determined that it was low. We also found that beta-thalassemia homozygotes in sardinia have a higher incidence of alpha-thalassemia than normals and beta thalassemia heterozygotes because a significantly greater number of these homozygotes are also homozygous for the alpha-thalassemia-2 lesion. These findings support the theory that coinheritance of alpha- thalassemia mitigates the severity of beta-thalassemia and suggest that the protection is most pronounced when two alpha-globin genes are deleted.