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11.
A study was conducted on 140 pregnant women at and after 28 weeks of pregnancy for finding out the relationship of cervical length and position with onset of preterm labour. Incidence of preterm labour was significantly higher (p < 0.001) in women with central position of cervix (54.67%) than that with posterior position of cervix (10.77%). Onset of preterm delivery was closely related to cervical length of 2.5 cm or less irrespective of central (82.75%) or posterior (20%) position of cervix (p < 0.001).  相似文献   
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Despite the dramatic success of inhaled steroids in controlling asthma symptoms there remains a small number of patients in whom asthma can only be treated with continuous oral steroids. Eighteen such patients, aged 19-62 years (seven males, 11 females) were followed in an open trial of nebulized budesonide over 12-18 months. All had required at least 7.5 mg or more daily prednisolone to control their symptoms over the preceeding 2 or more years and were taking 1200 micrograms beclomethasone dipropionate or 1600 micrograms budesonide daily. With a daily dose ranging between 4 and 8 mg nebulized budesonide, 14 patients successfully stopped oral steroids while in three the dose was reduced; only one patient failed to benefit. There was an increase in the mean FEV1 from 1.9 (+/- 0.9) to 2.2 (+/- 0.9) l, and in the mean morning PEFR, from 238 (+/- 119) to 286 (+/- 130) l min-1. There was also a significant decrease in the mean number of hospital admissions for acute severe asthma, from 1.5 (+/- 1.8) to 0.9 (+/- 1.1) per year. These findings should encourage a careful and controlled evaluation of nebulized steroids as a substitute for oral steroids in this difficult group of asthmatics.  相似文献   
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Phonophoresis is defined as the migration of drug molecules, contained in a contact agent, through the skin under the influence of ultrasound. Several drugs have been introduced into the body by this technique. The design of a phonophoretic drug delivery system is in developmental stages in various research laboratories. Parameters affecting the delivery of drugs by this technique and devices available for drug delivery purposes are discussed in this review.  相似文献   
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Carcinoma of the esophagus shows a strong male predominance and other epidemiologic differences from cancers arising at other sites. In this study, the prevalence of Y chromosome loss in 29 carcinomas of the esophagus and 53 carcinomas arising elsewhere in the aerodigestive tract was assessed by in situ hybridization of formalin-fixed paraffin-embedded tissue sections. Absence of the Y chromosome was defined as (1) negative staining for Y in neoplastic cells with positive staining for Y in immediately adjacent nonneoplastic epithelial and stromal cells, (2) positive staining of neoplastic cells with control probes for chromosomes X and 17, and (3) similar results at different stringencies and levels of protein digestion. According to these criteria, absence of the Y chromosome was observed in 13 of 14 (93%) adenocarcinomas of the esophagus, 8 of 13 (62%) squamous cell carcinomas of the esophagus, and 5 of 53 (9%) carcinomas arising in other sites. For the neoplasms examined, Y chromosome deletion was strongly and selectively associated with carcinomas, particularly adenocarcinomas, of the esophagus (P < .0001). These findings suggest that Y chromosome loss may be pathogenetically significant in these neoplasms. © 1993 Wiley-Liss, Inc.  相似文献   
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Prostate-specific antigen (PSA) production by nonprostatic tissues has been reported, casting doubts on its specificity. The immunohistochemical relative specificity and sensitivity of PSA expression using monoclonal and polyclonal anti-PSA was analyzed on 60 prostate carcinomas, 40 normal seminal vesicles, and 310 nonprostatic tumors. All nonprostatic tumors proved negative with both antibodies. However, 13 (32%) seminal vesicles showed immunoreactivity with polyclonal anti-PSA, but none showed immunoreactivity with the monoclonal antibody. The sensitivity of the 2 antibodies for prostate cancer varied with tumor grade. In Gleason pattern 3, both antibodies showed diffuse immunostaining in all cases. In Gleason pattern 5, polyclonal anti-PSA showed diffuse (>95%) tumor cell positivity in 18 cases (90%), while with the monoclonal antibody, 7 cases (35%) showed only focal (<10%) tumor cell immunoreactivity. Thus, monoclonal anti-PSA seems to be useful in small gland proliferations in which the differential diagnosis includes seminal vesicle, while for poorly differentiated neoplasms, polyclonal anti-PSA is considered superior. Sections of high-grade prostate cancer should be included as positive controls for PSA immunostaining.  相似文献   
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