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991.
BACKGROUND: Although the national rate of gonorrhea declined 68% from 1975 to 1995, rates remain high in many inner-city areas. In 1995, the gonorrhea rate in Newark, NJ, was five times the US rate. OBJECTIVE: To determine factors associated with acquisition of gonorrhea by men in Newark. STUDY DESIGN: A case-control study conducted at the sexually transmitted disease (STD) clinic in Newark, comparing males 15 to 29 years with culture-confirmed gonorrhea to controls with no STD. RESULTS: Compared with controls, males with gonorrhea more frequently reported at least 1 casual sex partner within the preceding month (adjusted odds ratio [OR], 3.2; 95% CI, 1.8-5.7), sex after using marijuana during the preceding month (OR, 2.4; 95% CI, 1.1-5.3), and a history of incarceration (OR, 2.1; 95% CI, 1.2-3.7). Of males with casual partners, having a new casual sexual relationship (onset within the past month) was particularly risky for gonorrhea (OR, 3.9; 95% CI, 1.2-12.7). Incorrect condom use was highly prevalent for both cases and controls. Many persons with gonorrhea reported that they were not willing to consistently use condoms or to have only one partner. CONCLUSIONS: Sex with casual partners is associated with gonorrhea in males, and may be a difficult practice to change. Condoms are often used incorrectly, if at all, in this population. Prevention strategies, in addition to the promotion of condom use and monogamy, may be necessary.  相似文献   
992.
PURPOSE: Phytochemicals in plants may have cancer preventive benefits through antioxidation and via gene-nutrient interactions. We sought to determine the effects of pomegranate juice (a major source of antioxidants) consumption on prostate-specific antigen (PSA) progression in men with a rising PSA following primary therapy. EXPERIMENTAL DESIGN: A phase II, Simon two-stage clinical trial for men with rising PSA after surgery or radiotherapy was conducted. Eligible patients had a detectable PSA > 0.2 and < 5 ng/mL and Gleason score < or = 7. Patients were treated with 8 ounces of pomegranate juice daily (Wonderful variety, 570 mg total polyphenol gallic acid equivalents) until disease progression. Clinical end points included safety and effect on serum PSA, serum-induced proliferation and apoptosis of LNCaP cells, serum lipid peroxidation, and serum nitric oxide levels. RESULTS: The study was fully accrued after efficacy criteria were met. There were no serious adverse events reported and the treatment was well tolerated. Mean PSA doubling time significantly increased with treatment from a mean of 15 months at baseline to 54 months posttreatment (P < 0.001). In vitro assays comparing pretreatment and posttreatment patient serum on the growth of LNCaP showed a 12% decrease in cell proliferation and a 17% increase in apoptosis (P = 0.0048 and 0.0004, respectively), a 23% increase in serum nitric oxide (P = 0.0085), and significant (P < 0.02) reductions in oxidative state and sensitivity to oxidation of serum lipids after versus before pomegranate juice consumption. CONCLUSIONS: We report the first clinical trial of pomegranate juice in patients with prostate cancer. The statistically significant prolongation of PSA doubling time, coupled with corresponding laboratory effects on prostate cancer in vitro cell proliferation and apoptosis as well as oxidative stress, warrant further testing in a placebo-controlled study.  相似文献   
993.
In order to avoid any artifactual pharmacological interferences with anaesthetic agents, a procedure has been developed for working on the awake, anaesthetic-free rat in a head-restrained condition. It allows, on the same animal and over several consecutive days, single-unit recordings in combination with systemic or local pharmacology (microiontophoresis or micropressure ejections), as well as monitoring vigilance states via the electroencephalogram and the electromyogram. After the cementing of a special "U"-shaped device on its skull under general anaesthesia, the animal is progressively habituated to stay daily, for several hours, under a painless corresponding stereotaxic restraint. This system can be easily adapted to different stereotaxic frames and, because of its spatial flexibility for targetting the desired rostrocaudal or lateral positions, allows access to a large number of cerebral structures. Experiments performed on Globus Pallidus, Substantia Nigra, and Locus Coeruleus neurons, combining the different possibilities of this system, are reported. They demonstrate, on the awake anaesthetic-free head-restrained rat, and under suitable ethical conditions, the feasibility of single-unit recordings of identified neurons associated with the study of their pharmacological reactivity after systemic or local drug administrations without any other drug interferences, and in physiologically relevant conditions such as the spontaneous alternance of vigilance states.  相似文献   
994.
Despite the introduction of screening procedures and an increased public awareness of prostate cancer, a substantial number of patients present with locally advanced prostate cancer. Traditional therapies (such as radiation therapy or radical prostatectomy) applied either alone or in combination fail to control local disease in a large number of cases and have no effect on disseminated disease. Recent advances in molecular oncology and genetics have led to such novel therapies as p53 gene therapy, which we are currently evaluating in a clinical protocol in patients with locally advanced (nonmetastatic) prostatic cancer. Ad5CMVp53 (RPR/INGN 201) has previously shown promise in both patients with lung cancer and those with head and neck cancer. The traditional end points used to appraise prostate cancer preclude rapid evaluation of the patient's disease and prevent modification of the therapeutic strategy, and we suggest that the pathologic stage after therapy be evaluated as an intermediate end point.  相似文献   
995.
996.
Surgery today owes much to the services of early practitioners who made their advances as a result of wide clinical experience and compassion. This two‐part series explores the careers of Percivall Pott and William Arbuthnot Lane. Percivall Pott was born in 1714 in east London. Pott was apprenticed to Nourse of St. Bartholomew's Hospital at 15 years of age. After gaining licence to practise in 1736, Pott remained as surgeon to the hospital from 1745 till his retirement aged 73. After falling from his horse in 1756, Pott sustained a fracture of his leg, confining him to bed. During this time, he wrote on his own fracture, as well as hernia and head injuries. Several diseases are named after him, viz. Pott's fracture, Pott's puffy tumour, and Pott's disease of the spine. He was the first to describe cancer of the scrotum in chimney sweepers, as the earliest occupational cancer.   相似文献   
997.
OBJECTIVES: This study examined the effects of aneurysm repair in a rat model of myocardial infarction on functional indices and on the spatiotemporal distribution of cardiac contractile protein and natriuretic peptide messenger RNA. METHODS: In a rat infarct model, expanded left ventricular aneurysms were plicated 4 weeks after infarction. At 30 weeks, transverse heart sections were taken at 4 levels (apex [level 1] through base [level 4]) and assessed by in situ hybridization histochemistry to determine regional messenger RNA levels of pre-pro-atrial natriuretic peptide, cardiac alpha-actin, skeletal alpha-actin, myosin light chain-2v, and beta-myosin heavy chain. RESULTS: Rats with plicated left ventricular aneurysms had reduced left ventricular endocardial circumference (19%, P <.005), lower heart weight ratio (31%, P <.05), left ventricular end-diastolic pressures (51%, P <.05), and increased +/-dP/dt (34%-38%, P <.05). Cardiac messenger RNA levels of pre-pro-atrial natriuretic peptide were reduced in the septum (levels 2 and 3), and skeletal alpha-actin levels were reduced in the septum and left ventricular free wall of plicated rats (level 3). beta-Myosin heavy chain levels were markedly reduced in peri-infarct regions of the left ventricular free wall, septum, and right ventricle in plicated rats at level 4, whereas myosin light chain-2v levels were reduced at levels 2 and 4 in the left ventricular free wall and at level 4 in the right ventricle. CONCLUSIONS: Plication of left ventricular aneurysm after infarction in the rat significantly reduced cardiac hypertrophy, improved cardiac function, and reduced the upregulation of pre-pro-atrial natriuretic peptide and both fetal and adult contractile protein isoforms associated with cardiac hypertrophy.  相似文献   
998.
999.
Takayasu arteritis (TA) is a large vessel vasculitis that usually affects young female patients during the second and third decades of life, but has been reported in children as young as 24 months of age. Aim of this report was to describe four children (two girls) with TA, as well as summarizing main published studies. The mean age at presentation of our cases was 11 years (range 8–15). Three patients were Caucasians and one Asian. Arterial hypertension was the commonest mode of presentation followed by systemic symptoms. Other related symptoms were due to ischemia and consisted of abdomen, chest, and limb pain. An abdominal bruit was noted in only one patient. Inflammation markers were always abnormal. Angiography was performed in all cases; left subclavian artery and common carotid artery were more frequently involved. Renal artery stenosis was observed in two patients. One boy was diagnosed as having an associated immune deficiency (Wiskott-Aldrich syndrome). Treatment modalities included prednisone (n = 4), methotrexate (n = 3), and mycophenolate mofetil (MMF) (n = 1). Surgery was required in two patients. Follow-up ranged from 3 to 10 years since diagnosis. In three cases antihypertensive drugs and methotrexate were stopped, and prednisone was reduced to 7.5 mg/day.  相似文献   
1000.
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