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51.
Compared with both industrialized countries and other less developed parts of the world, most of sub-Saharan Africa suffers inordinately from sexually transmitted diseases (STDs). It has high prevalence rates of traditional STDs, such as gonorrhea and syphilis, and if accurate seroprevalence surveys were to be done, it would probably prove to have the highest HIV seropositive incidence in the world. Unlike the pattern in the West, AIDS is primarily a heterosexually transmitted disease in Africa. This appears to be largely because of the prevalence of other untreated or improperly treated STDs. Therefore to lower the incidence of STDs would be to curtail the spread of HIV infection. The problem becomes how exactly to accomplish this. Most STD cases are never even presented at biomedical health facilities; they are presented to traditional healers. Both healers and their patients seem to believe that traditional STD cures are more effective than 'modern' cures, although the former are probably biomedically ineffective. While there is scant ethnomedical literature on STDs in Africa, the present paper presents Swaziland findings and related evidence from other African societies that the ultimate cause of several common STDs is believed to be the violation of norms governing sexual behavior, requiring traditional rather than biomedical treatment. Traditional healers therefore need to be a central part of any scheme to lower the incidence of STDs.  相似文献   
52.
Introduction: apoptosis in the immune system.   总被引:5,自引:0,他引:5  
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53.
F E Liss  S M Green 《Hand Clinics》1992,8(4):755-768
Although capsular injuries of the PIP joints are common, their management is frequently complicated. Successful treatment must begin with a detailed history because reviewing the mechanism of injury may provide information relevant to the pathomechanics of the capsular disruption and facilitate making an accurate diagnosis. Grades I and II volar plate and collateral ligament sprains represent the vast majority of PIP joint injuries. They are best treated with a short period of dorsal splinting followed by supervised mobilization. Although splinting is also applicable for grade II sprains associated with instability and most grade III sprains, the initial period of immobilization should be longer. The prognosis for recovery is generally good, although some residual tenderness or joint stiffness are common complications. Dorsal capsular injuries, if unrecognized, result in deformity rather than instability. The majority of these injuries can also be treated by closed means, but they require more prolonged immobilization and more commonly result in reduced mobility than volar plate and collateral ligament injuries. Capsular injuries that are compound, irreducible, or associated with a large intraarticular fracture can result in serious problems. Frequently, these injuries require primary surgical treatment, particularly in the case of the irreducible dislocation, which always requires surgery. An exception to the generally poor prognosis of these injuries is the irreducible volar dislocation because the central tendon remains intact permitting early postoperative joint mobilization. A chronic dislocation or late instability are fortunately not common sequela of capsular injuries; however, when they do occur, surgery is required.  相似文献   
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Total and subcellular (cytosol and nuclear) concentrations of estrone (E1), estradiol (E2), and androstenedione were determined in non-malignant (n = 61) and malignant (n = 65) human breast tissues obtained from post-menopausal women. The 17 beta-hydroxysteroid dehydrogenase (17 beta-OH-SDH) activity was determined in 800g supernatant fraction. Total estrogens, E1 and E2 levels and 17 beta-OH-SDH activity were significantly (p less than 0.005, 0.0005, 0.001, respectively) higher in malignant than in non-malignant breast tissues. We failed to observe significant changes in subcellular steroid concentrations or enzyme activity associated with patients' obesity or tumor estrogen receptor status. When the steroid levels were analyzed in relation to clinical staging of the disease, nuclear contents of estradiol were significantly higher (p less than 0.005) in Stage-IV patients than in those with less advanced disease (Stages I to III). 17 beta-OH-SDH activity was significantly (p less than 0.001) lower in patients with advanced disease than in those with relatively less advanced (Stages I to III) disease and was positively correlated with tissue concentration of androstenedione. Our present data indicate that differential intracellular metabolism of steroid hormones may have some influence on availability of estradiol at nuclear sites. In postmenopausal women, local interconversion of estrogens may provide sufficient estrogenic stimulus to enhance the growth and progression of breast tumors.  相似文献   
56.
Several commercial pilocarpine preparations have been compared for their efficacy of drug delivery as evaluated by changes in pupil diameter, and return to base-line pupil size, in rabbits and squirrel monkeys. Adsorbocarpine, Isoptocarpine, Pilocar, all at 2%, and Pilopine HS gel, 4%, were used. In albino rabbits the order of efficacy, as judged by area under the curve, or maximal pupil diameter change, was Pilopine greater than Isoptocarpine = Adsorbocarpine greater than Pilocar = saline (prepared in this laboratory). In general, greater areas under the curve were associated with greater changes in pupil diameter. Pupil diameter had returned to normal by a maximum of 5 hours after drop instillation. In squirrel monkeys, the maximum pupillary change was statistically (P greater than 0.05) the same for all preparations, as was the percentage change in pupil diameter at 6 hours since pupils were still somewhat constricted at this time after drop instillation. The differences in area under the curve were minor. The greater response in primates compared to rabbits may be due to differences in pigment, intraocular kinetics and a far more active ciliary muscle in primates. Also studied were newly developed, non-surfactant containing, preservative-free polymer- and microparticle-based vehicles. Some of the vehicles, based on cyanoacrylate, modified hyaluronate, anionic copolymers, polyvinyl-pyrrolidone, cross-linked gelatin and microparticles showed greater pupillary changes and areas under the curve in rabbits compared to saline vehicle. When compared to commercial preparations in the monkey eye cyanoacrylate block copolymer and modified hyaluronate showed an increase in efficacy. Polyvinylpyrrolidone, anionic copolymer and cross-linked gelatin were equal to the commercial preparations.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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58.
The Ca antigen has been reported to be present on the surface of malignant but not, with few exceptions, non-malignant cells. We investigated the potential usefulness of the monoclonal Ca 1 antibody in differentiating oral squamous cell carcinoma from non-malignant or premalignant oral neoplasms. Paraffin-embedded sections from 33 biopsy specimens of 12 hyperplastic and 21 neoplastic oral lesions were examined by immunohistochemical staining. Seven of the 33 specimens showed positive staining for Ca antigen. Fifteen of 21 specimens of oral squamous cell carcinoma were negative for Ca antigen, and one case of focal keratosis was positive. The results indicate that the use of the Ca 1 antibody to distinguish oral squamous cell carcinoma from non-malignant or premalignant oral lesions is highly unreliable.  相似文献   
59.
PURPOSE: Adjuvant chemotherapy, especially with anthracyclines, is known to cause acute and chronic cardiotoxicity in breast cancer patients. We studied the cardiac effects of chemotherapy in a population-based sample of breast cancer patients aged > or = 65 years with long-term follow-up. PATIENTS AND METHODS: In the Surveillance, Epidemiology, and End Results (SEER)-Medicare database, we analyzed treatments and outcomes among women > or = 65 years of age who were diagnosed with stage I to III breast cancer from January 1, 1992 to December 31, 1999. Propensity scores were used to control for baseline heart disease (HD) and other known predictors of chemotherapy, and Cox proportional hazards models were used to estimate the risk of cardiomyopathy (CM), congestive heart failure (CHF), and HD after chemotherapy. RESULTS: Of 31,748 women with stage I to III breast cancer, 5,575 (18%) received chemotherapy. Chemotherapy was associated with younger age, fewer comorbidities, hormone receptor negativity, multiple primary tumors, and advanced disease. Patients who received chemotherapy were less likely than other patients to have pre-existing HD (45% v 55%, respectively; P < .001). The hazard ratios for CM, CHF, and HD for patients treated with doxorubicin (DOX) compared with patients who received no chemotherapy were 2.48 (95% CI, 2.10 to 2.93), 1.38 (95% CI, 1.25 to 1.52), and 1.35 (95% CI, 1.26 to 1.44), respectively. The relative risk of cardiotoxicity among patients who received DOX compared with untreated patients remained elevated 5 years after diagnosis. CONCLUSION: When baseline HD was taken into account, chemotherapy, especially with anthracyclines, was associated with a substantially increased risk of CM. As the number of long-term survivors grows, identifying and minimizing the late effects of treatment will become increasingly important.  相似文献   
60.
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