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51.
52.
Chen MZ  Hsueh PR  Lee LN  Yu CJ  Yang PC  Luh KT 《Chest》2001,120(4):1072-1077
STUDY OBJECTIVES: To investigate the clinical, epidemiologic, and microbiological characteristics of community-acquired pneumonia (CAP) due to Acinetobacter baumannii. METHODS: Retrospective chart and radiographic reviews of all patients who were admitted to National Taiwan University Hospital from January 1993 to August 1999, fulfilled the criteria for CAP, and had an isolate of A. baumannii from blood or pleural fluid at hospital admission. RESULTS: Thirteen patients (9 men and 4 women; age range, 37 to 85 years) met the criteria. Conditions associated with the infection included male gender, old age, alcoholism, malignancy, cerebrovascular disease, diabetes mellitus, renal disease, and liver cirrhosis. Eleven patients (85%) acquired the infection during the warmer months of April to October. Twelve patients (92%) had a fulminant course presenting with septic shock and respiratory failure, and 11 patients (85%) needed ventilator support and were treated in an ICU. Six patients (46%) had leukopenia. Lobar consolidations were found in 12 patients (92%), and pleural effusions were present in 4 patients (31%). All patients had positive blood culture results, two patients (15%) had positive pleural effusion culture findings, and nine patients (69%) positive sputum culture results. All the isolates were susceptible to imipenem, and most were susceptible to aminoglycosides, ceftazidime, ciprofloxacin, and extended-spectrum penicillins. Eight patients (62%) died. Four of the five survivors were initially treated with combination of a third-generation cephalosporin and an aminoglycoside. CONCLUSION: A. baumannii should be considered as a possible etiologic agent in community-acquired lobar pneumonia when (1) patients with a fulminant course present during the warmer and more humid months of the year, and (2) patients are younger alcoholics. A good sputum smear, defined as a Gram stain smear of an adequate sputum specimen that comes from the lower respiratory tract and contains > 25 leukocytes per high-power (100x) field on microscopic examination, can help early diagnosis and treatment. A combination of a third-generation cephalosporin and an aminoglycoside may be appropriate empirical therapy.  相似文献   
53.
BACKGROUND: Although it is widely recognized that there are familial elements in the pathogenesis of hypertension, remarkably little is known about the influence of family history on response to specific antihypertensive agents. METHODS: This study was designed to address that issue by comparing the depressor response to lisinopril in a dose range of 10 to 40 mg in 74 patients enrolled as sibling pairs. Because all patients were treated with lisinopril, ambulatory blood pressure monitoring (ABPM), an objective measure not influenced by the investigators, was used to assess the primary blood pressure (BP) outcome variable. RESULTS: Diastolic BP was highly correlated between sibling pairs at baseline (r = 0.476; P < .03) and on treatment (r = 0.524; P = .0021). Ethnicity/race had a striking influence on lisinopril dose and response rate. Among African American patients, 23 of 28 reached the top dose of 40 mg/day, whereas only 14 of 36 Caucasian patients reached that dose level. Among Caucasians, 92% responded, and only 48% of African Americans. Responders were characterized by being younger and heavier, having significantly lower microalbuminuria at baseline, higher baseline renal plasma flow (RPF), and higher urinary kallikrein. CONCLUSION: Among Caucasians, the presence of a hypertensive sibling predicts a striking therapeutic response to angiotensin converting enzyme inhibition.  相似文献   
54.
Papillary thyroid carcinomas with lung metastases.   总被引:3,自引:0,他引:3  
BACKGROUND: Limited information is available on the presentation, treatment outcomes, and prognostic factors of papillary thyroid carcinoma with lung metastases. METHODS: This study retrospectively analyzed the data of 2003 patients with thyroid cancer who were treated and followed up at Chang Gung Memorial Hospital from January 1979 to December 2002. In total, 1516 papillary thyroid carcinomas were enrolled. One hundred two (6.7%) papillary thyroid carcinomas with lung metastases were followed including 57 women with mean age of 41.7 +/- 17.3 years and 45 men with mean age of 49.6 +/- 17.2 years. These patients included 52 patients with papillary thyroid carcinoma who presented with lung metastases at the time of diagnosis. The 102 cases of papillary thyroid carcinomas with lung metastases included 72 cases with lung metastases only, and 30 cases with other organ involvement. RESULTS: After mean follow-up periods of 8.8 +/- 0.6 years, 28 (27.5%) of the patients with lung metastasis died, while 6 improved to clinical stage I. The 5-, 10-, 15-, and 20-year survival rates in patients with papillary thyroid carcinoma without distant metastasis and in the lung metastases groups were 99.0%, 98.5%, 98.0%, 98.0%, and 91.3%, 75.0%, 64.0%, 51.2%, respectively. Comparing the Kaplan-Meier survival curves between the patients with papillary thyroid carcinomas with lung metastases only and those with multiorgan metastases demonstrates no statistically significant difference in mortality rates. However, age, gender, postoperative thyroglobulin (Tg) level and tumor size displayed statistically significant differences between the lung metastases and no distant metastasis groups. Fifty of the 102 patients with papillary thyroid carcinomas with lung metastases developed lung metastases during follow-up. Larger amounts of remnant thyroid tissues with higher Tg levels were noted in these patients compared to those without distant metastasis. CONCLUSIONS: The prognosis of patients with papillary thyroid carcinoma with lung metastases at time of diagnosis is the same as for those whose lung metastases are discovered later. Survival analysis demonstrates no difference between lung metastases and multiorgan metastases.  相似文献   
55.
Initial and cyclic recruitment of ovarian follicles   总被引:36,自引:0,他引:36  
Mammalian ovaries consist of follicles as basic functional units. The total number of ovarian follicles is determined early in life, and the depletion of this pool leads to reproductive senescence. Each follicle develops to either ovulate or, more likely, to undergo degeneration. The dynamics of ovarian follicle development have interested endocrinologists and developmental biologists for many years. With the advent of assisted reproductive techniques in humans, the possibility of regulating follicle development in vivo and in vitro has gained clinical relevance. In this review, we focus upon key branching points during the development of ovarian follicles as well as factors involved in determining the eventual destiny of individual follicles. We discuss inconsistencies in the literature regarding the definitions of follicle recruitment and selection and propose to name the two major steps of follicle development as initial and cyclic recruitment, respectively. Because some of these disparities have arisen due to differences in the animal systems studied, we also compare the development of the ovarian follicles of both humans and rats. We also review the status of knowledge of several puzzling clinical issues that may provide important clues toward unlocking the mechanisms of follicle development.  相似文献   
56.
Two pancreatic acinar cell carcinomas with distinctive morphologic features are described. Both tumors showed a variable combination of different histomorphologic patterns formed by tumor cells in different degrees of acinar differentiation. They caused diagnostic problems involving differential diagnosis from normal pancreas and from mixed acinar-endocrine tumor. The presence of mitosis, nuclear atypia, and tumor necrosis are helpful for recognizing its neoplastic nature, and the ultrastructural finding of zymogen-like but not neurosecretory granules prevented the misdiagnosis of a mixed acinar-endocrine tumor. Immunohistochemical studies revealed variable immunostaining patterns corresponding to different types of tumor cell present. Both tumors were found to be aneuploid by flow cytometric DNA study. Our study confirmed previous observations that pancreatic acinar cell carcinomas are highly malignant tumors in spite of the fact that they can differentiate into highly differentiated acinar cells.  相似文献   
57.
Ticlopidine-associated aplastic anemia   总被引:2,自引:0,他引:2  
 Serious hematologic complications associated with ticlopidine have been reported, including aplastic anemia. We report here an additional case of fatal aplastic anemia due to ticlopidine. A 66-year-old male patient developed fever and pancytopenia 2 months after ticlopidine was started. Despite the administration of granulocyte colony-stimulating factor (G-CSF) and broad-spectrum antibiotics, as well as aggressive red cell and platelet transfusions, the patient died 16 days after admission due to septic shock. Eighteen other cases of ticlopidine-induced aplastic anemia published in the English literature are also reviewed and presented here. Eight of the total 19 patients (including the one reported here) have died, mostly due to infection. Of the seven who received supportive treatment only, four had spontaneous recovery. Nine cases were treated with G-CSF or granulocyte-macrophage colony-stimulating factor (GM-CSF), and response was observed in only four of them. Several other cases were treated with high-dose corticosteroids or androgens; however, it was not possible to evaluate the efficacy of these treatments because of the limited number of cases. In the absence of satisfactory treatment for ticlopidine-induced aplastic anemia at present, it may be reasonable to try antilymphocyte globulin or cyclosporine. Also, great efforts should be made in the prevention and management of infection accompanying this disease. Received: 2 November 1997 / Accepted: 12 January 1998  相似文献   
58.
A sensitive and specific in vitro granulosa cell aromatase bioassay was adapted to measure bioactive FSH (bio-FSH) levels in urine samples. Urinary levels of bio-FSH, immunoreactive LH, estrone conjugates, and pregnanediol-3-glucuronide (PdG) were measured in first morning urine samples during the menstrual cycle in six cycling women and four lowland gorillas. The cycle length of women was relatively constant [28 +/- 1 (+/- SD) days], but varied from 28-38 days for lowland gorillas; the length of the luteal phases was relatively constant for both. All subjects had a midcycle LH peak and a luteal phase elevation in PdG. In addition, urinary estrogen excretion displayed a midcycle elevation that preceded the LH peak and a luteal phase increase similar to that of PdG. The bio-FSH levels in urine of cycling women, although at almost 100-fold higher concentrations, exhibited a pattern that closely resembled that of serum bio-FSH levels reported earlier, with an early follicular phase rise and a midcycle peak. Statistical analysis indicated a highly significant correlation (r = 0.90) between serum and urinary bio-FSH levels during the human menstrual cycle and in women in several hypo- and hypergonadotropic states, including oral contraceptive pill users, hypothalamic amenorrhea, premature ovarian failure, and postmenopause. Although a midcycle bio-FSH surge was also detected in lowland gorillas, two peaks of bio-FSH levels were consistently found during the follicular phase. The late follicular phase increase in bio-FSH levels was presumably involved in follicle selection and preceded the midcycle FSH peak by about 6 days, whereas the timing of the early follicular phase peak was variable, suggesting the involvement of complex regulatory mechanisms. These findings suggest that measurement of urinary bio-FSH levels in humans reflects serum bio-FSH in subjects in several physiological and pathological states. Studies of urinary bio-FSH levels in humans and nonhuman primates are useful in monitoring menstrual cycles, and the gorillas may be a model for understanding human reproductive cycles. The urinary granulosa cell aromatase bioassay should be useful for future assessment of bio-FSH levels in situations where serum measurements are impractical or in animal species for which specific FSH RIAs are not available.  相似文献   
59.
Multiple acyl-coenzyme A dehydrogenase deficiency (MADD) is a rare metabolic disorder with a dramatic clinical presentation. It was recently discovered that MADD may present at an advanced age.The clinical and laboratory data of an index patient and patients previously diagnosed at our institution were collected. A systematic review of previous studies retrieved from the PubMed, MEDLINE, and Embase databases published by February 1, 2020 was performed to collect patients with very-late-onset MADD (VLO-MADD, onset age > 60 years) globally and patients with late-onset MADD (LO-MADD, onset age < 60 years) in Taiwan. The clinical characteristics of the VLO-MADD patients were compared to those of LO-MADD patients.We report a patient with VLO-MADD who developed the first symptom at the age of 61 years. The patient presented with a Reye-like syndrome after taking aspirin for coronary artery disease. Repeated bouts of weakness were noted. Two variants of c.250 G > A (;) 419C > T were observed in the ETFDH gene. Another four patients with VLO-MADD were identified globally. Eighteen patients with LO-MADD were collected from our department and previously reported patients in Taiwan. There was no difference in the clinical symptoms (except for the onset age) or laboratory data between these two groups. Homozygous variants were not observed in any patients in the VLO-MADD group but were detected in 12 patients (66.6%) in the LO-MADD group (p = 0.014).Patients with MADD may first show symptoms in their 6th decade or beyond. The disease course may lead to erroneous diagnoses in this age group.  相似文献   
60.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative viral pathogen of coronavirus disease 2019 (COVID-19), appears to have various clinical presentations and may result in severe respiratory failure. The global SARS-CoV-2-associated viral pneumonia pandemic was first reported in December 2019 in China. Based on known pharmacological mechanisms, many therapeutic drugs have been repurposed to target SARS-CoV-2. Among these drugs, remdesivir appears to be the currently most promising according to several clinical trials and reports of compassionate use. In this mini-review, we summarize the current evidence on the efficacy and challenges of remdesivir for the treatment of coronavirus disease 2019 (COVID-19).  相似文献   
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