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111.
This prospective, open, randomized clinical study compared the efficacy and tolerability of norfloxacin and ciprofloxacin in adult patients with complicated urinary tract infection, defined as infection in the presence of an underlying anatomic or functional abnormality of the urinary tract. Seventy-two patients were randomized, 37 received norfloxacin (400 mg orally twice daily for 10-21 days) and 35 received ciprofloxacin (500 mg orally every 12 hours for 14-21 days). Patients were clinically assessed, and urine cultures were obtained following two to four days of therapy, and five to nine days and four to six weeks after discontinuation of therapy. Seventy-two percent of the norfloxacin group and 79 percent of the ciprofloxacin group were considered cured. This difference was not significant. One failure of norfloxacin therapy was associated with the emergence of resistant Pseudomonas aeruginosa. Following norfloxacin therapy, in 2 patients superinfections developed with resistant organisms (Staphylococcus epidermidis [1] and Pseudomonas maltophilia [1]). Twelve patients, 6 in each group, experienced adverse reactions, which were considered related to the study drug therapy in only four instances. Our results indicated comparable efficacy and tolerability of norfloxacin and ciprofloxacin in the treatment of complicated urinary tract infection in adults.  相似文献   
112.
Serum phenylalanine and tyrosine levels were measured in 26 patients with severe depression before and after receiving electroconvulsive therapy. The phenylalanine:tyrosine [P:T] ratio declined significantly for those responding to treatment but not for nonresponders. These findings are discussed in relation to tetrahydrobiopterin, the essential cofactor for the formation of noradrenaline, dopamine and serotonin and the hydroxylation of phenylalanine to tyrosine.  相似文献   
113.
STUDY OBJECTIVE: To evaluate the clinical use of a cardiorespiratory rate monitor in patients receiving epidural opioids following major surgery. DESIGN: For 6 hours during the night following surgery, patients were continuously monitored with a cardiorespiratory rate monitor and a pulse oximeter, as well as by an in-room observer. SETTING: Postoperative surgical ward at a university hospital. PATIENTS: Eight ASA physical status I and II patients ages 30 to 76 years. INTERVENTIONS: Any bradypneic, hypoxemic, bradycardic, or tachycardic event was confirmed by the observer and recorded. MEASUREMENTS AND MAIN RESULTS: The cardiorespiratory rate monitor accurately identified true bradypneic episodes in five of the eight patients. There were no false-positive alarms. The respiratory rate monitor and the pulse oximeter identified one episode of hypoxemia. There were no episodes of bradycardia or tachycardia. CONCLUSIONS: The cardiorespiratory rate monitor is useful in patients at risk for bradypnea following surgery.  相似文献   
114.
Targeting of electron affinic radiosensitizers to DNA via reversible non-covalent intercalative binding has potential for increasing sensitizer concentrations locally at the DNA target while decreasing accessibility to reductases responsible for bioactivation and cytotoxicity. We have prepared an DNA-targeted acridine-linked 2-nitroimidazole (NLA-1) as an example of such a compound. NLA-1 binds reversibly to DNA with an affinity similar to 9-aminoacridine, and is approximately 1000 times more potent than MISO as a cytotoxin, despite a similar reduction potential. It shows less enhancement of cytotoxicity under hypoxia (5- to 6-fold) than does MISO (approximately 11-fold), but is a potent hypoxia-selective radiosensitizer in AA8 cells with a concentration for an enhancement ratio of 1.6 (C1.6) of 9 microM. The mean intracellular concentration at the C1.6 is 400 microM, on which basis its potency is about twice that of MISO. The in vitro therapeutic index (aerobic cytotoxic potency/hypoxic C1.6) of NLA-1 is approximately 6-fold lower than that for MISO. NLA-1 lacks radiosensitizing activity against SCCVII or EMT6 tumors in vivo at the maximum tolerated dose (MTD) of 100 mumol.kg-1.  相似文献   
115.
116.
Both H2O2 (IC50 = 70 microM) and HOCl (IC50 = 8.5 microM) inhibited mitogen-induced MNL proliferation in a dose-dependent manner. This was found to be due to a depletion of intracellular ATP by at least two distinct mechanisms. HOCl and high concentrations (greater than 100 microM) of H2O2 inhibit ATP generation via sulfhydryl group oxidation on the active site of the glyceraldehyde-3-phosphate dehydrogenase (G3PDH) enzyme of the glycolytic pathway. On the other hand, low H2O2 concentrations cause ATP depletion by an activation of the DNA repair enzyme, poly(ADP-ribose)polymerase (pADPRP), leading to consumption of NAD+, an essential cofactor for G3PDH. The anti-oxidants ascorbate and cysteine protected MNL against the anti-proliferative effects of HOCl. Similar results were achieved with the HOCl-mediated inhibition of ATP production and G3PDH activity. However, ascorbate was unable to protect against H2O2-mediated inhibition of MNL functions, while cysteine protected against the inhibitory effects on ATP production and G3PDH activity, induced by this oxidant.  相似文献   
117.
Cranial sonography provides a noninvasive, portable method for imaging the infant brain. This study describes the time-dependent, sonographic findings of infantile cerebral infarction, as well as computed tomographic (CT) scan and neuropathologic confirmation. Three hundred ninety-five infants under 18 months of age were sonogrammed over a period of 18 months. Three infants were diagnosed by cranial sonography and confirmed by CT scan and/or autopsy to have acute ischemic cerebral infarcts. The cases were followed with serial cranial sonograms for up to 18 months of age. The acute sonographic findings included a hyperechoic zone around the infarcted tissue. The subacute infarct had a checkerboard pattern, while the chronic infarcts were anechoic.  相似文献   
118.
Human papillomavirus is associated with a variety of anogenital lesions, including genital warts, precancers and cancers. In male patients human papillomavirus has been identified in proliferative lesions ranging from penile and urethral warts to penile and prostatic cancers. We examined the association of human papillomavirus deoxyribonucleic acid (DNA) in 84 prostate tissue specimens. Specimens were selected from radical prostatectomy, transurethral resection or transrectal biopsy procedures. A total of 60 formalin-fixed, paraffin-embedded tissues (24 prostate cancer specimens, 16 benign prostatic hyperplasia specimens and 20 normal specimens) was examined by polymerase chain reaction and in situ hybridization. Also, 24 gelatin-embedded frozen prostate cancer specimens were examined for human papillomavirus DNA by polymerase chain reaction. Of the specimens 69 were deemed adequate for polymerase chain reaction analysis, whereas all 60 paraffin-embedded tissues were sufficient for in situ hybridization. Human papillomavirus DNA was detected in 2 normal tissues and 6 prostate cancers using polymerase chain reaction. None of the benign prostatic hyperplasia specimens was positive for human papillomavirus. Human papillomavirus typing results indicated that virus type 16 was present in each of the 8 positive specimens. Confirmation of the presence of human papillomavirus was obtained for 1 of the prostate cancers by nonisotopic in situ hybridization with biotinylated human papillomavirus genomic probes. The low prevalence of human papillomavirus in this study population does not strongly support an etiological role for the virus in prostate cancer.  相似文献   
119.
D H Streeten  G H Anderson 《Drugs》1992,43(6):805-819
Primarily hypervolaemic, high output forms of hypertension, with features indicating or strongly suggesting fluid overload as the cause of elevated cardiac output, resulting from renal disease with reduced glomerular filtration rate causing sodium retention, renal tubular causes of sodium retention, greatly excessive sodium intake and low renin hypertension, can be treated by reduction of sodium intake and potentiation of its excretion by diuretic therapy, removal of the cause (e.g. aldosteronoma), and calcium antagonists. Excessive vasoconstriction resulting from noradrenaline (norepinephrine) in neurogenic hypertension, phaeochromocytoma, orthostatic hypertension and alpha-adrenergic drug administration; angiotensin excess due to renal ischaemia brought about by aortic coarctation, renal arterial and arteriolar stenosis, intraluminal obstruction, external renal compression, renin-producing tumours, intrinsic kidney diseases and excessive renin substrate; and vascular structural disorders such as atherosclerosis, arteriolitides and fibrosis with or without calcification of major arteries may also induce hypertension. Secondary hypertension of uncertain mechanism may occur in hyperparathyroidism, hyper-or hypothyroidism, or acromegaly. All are best treated by appropriate correction of the endocrine excess or deficiency. It may also occur in pregnancy, where the mechanism may involve prostaglandin-thromboxane imbalance or calcium deficiency; calcium deficiency with some evidence of benefit from calcium supplements; and the recumbent hypertension paradoxically associated with autonomic failure. Excellent responses to specific correction of the underlying cause or pathogenetic mechanism is usual in young individuals but less frequent in older patients.  相似文献   
120.
Elective versus emergency surgery for patients with colorectal cancer.   总被引:11,自引:0,他引:11  
A prospective study of 570 patients presenting with colorectal cancer over a 6-year period was undertaken. Of these, 363 were admitted electively and 207 presented as emergencies. The outcome following elective admission was more favourable than after emergency admission. In the elective group the proportion of resected tumours was greater (77 versus 64 per cent, P less than 0.001), the operative mortality rate lower (9 versus 19 per cent, P less than 0.001) and the 5-year disease-related survival rate higher (37 versus 19 per cent, P less than 0.001). These differences may relate to the greater resection rates in the elective situation. Results of surgical intervention might be improved if emergency colorectal operations were undertaken by surgeons with more experience of this type of surgery.  相似文献   
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