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91.
Summary The extracellular matrix influences organogenesis by modulating cell behavior. In humans, collagen is the major matrix constituent of the adult intestinal wall and is synthesized by smooth muscle cells. The objective of the current study was to examine collagen production by fetal human intestinal smooth muscle cells isolated during intestinal morphogenesis. Techniques were developed for the isolation and culture of human fetal intestinal smooth muscle cells. The cultured cells were confirmed as muscle by immunohistochemical stains for cytoskeletal filaments and documentation of contractile behavior. In culture, these cells stained for mesenchymal and muscle cytoskeletal proteins: vimentin, actin, and desmin, and did not stain for neural or epithelial markers. The muscle cells contracted in response to acetylcholine, in contrast to human fetal dermal fibroblasts which did not contract appreciably. Collagen production was assayed by the uptake of [3H]-proline into collagenase-digestible protein. Collagen production was greatest at 11 weeks gestation, the youngest age studied. By 20 weeks gestation, collagen production had decreased to adult levels. However, when compared to another matrix-producing fetal mesenchymal cell, the dermal fibroblast, intestinal smooth muscle cells produced twice as much collagen. Collagen types were determined by polyacrylamide slab gel electrophoresis. Smooth muscle cells predominantly produced types I and III collagen chains. Therefore, collagen production is a significant function of human fetal intestinal smooth muscle cells, and probably plays a major role in the development of intestinal structure. The in vitro model presented here provides a means of studying the regulation of this collagen production throughout intestinal organogenesis.  相似文献   
92.
A 27-year-old woman with severe psychosis and mania associated with systemic lupus erythematosus was successfully treated with electroconvulsive therapy. Cyclophosphamide was given as an adjuvant. The use of electroconvulsive therapy in patients with lupus and psychiatric disorders is discussed.  相似文献   
93.
R M Fujitani  J L Mills  L M Wang  S M Taylor 《Journal of vascular surgery》1992,16(3):459-67; discussion 467-8
To determine the influence of unilateral internal carotid arterial occlusion (ICO) on Doppler frequency spectral analysis (DFSA) of the patent contralateral carotid artery, a retrospective review of 154 patients between July 1987 and December 1991 with angiographically confirmed ICO was performed, correlating duplex and arteriographic findings in a blinded fashion. Biplane arteriograms and bilateral carotid artery duplex studies that used a 5.0 MHz Doppler probe with a 1.5 mm3 sample volume at a 60 degree angle of insonation were performed on all patients. Each carotid artery was categorized by the severity of stenosis as quantified by arteriography: 1% to 15% (n = 41); 16% to 49% (n = 48), 50% to 79% (n = 21), 80% to 99% (n = 34), and bilateral occlusion (n = 10). DFSA peak systolic frequencies were commonly exaggerated in the presence of contralateral ICO and use of standard criteria for DFSA interpretation overestimated bifurcation stenoses in 43 of 89 lesions (48.3%) when determining nonhemodynamically significant lesions (less than 50% diameter reduction) with a sensitivity of only 57.3% and specificity of 96.9%. Conversely, prediction of hemodynamically significant lesions (greater than 50% diameter reduction) with standard criteria had 96.9% sensitivity but only 57.3% specificity. Modification of these criteria to account for the velocity increase or "jet effect" in the ipsilateral carotid artery system increased the sensitivity and specificity to 97.8% in predicting nonhemodynamically and hemodynamically significant stenoses respectively. A Doppler frequency spectrum with a peak systolic frequency (PSF) greater than 4.0 kHz and end-diastolic frequency (EDF) less than 5 kHz with an "open window" distinguished lesions with less than 50% diameter reduction.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
94.
95.
Acne-Prone Skin. Acne-prone skin appears to be more susceptible to certain extrinsic factors that can either exacerbate existing disease or generate new lesions. Awareness of the factors that could worsen or interfere with therapy is important. In addition, identification of patients with minimal acne who are prone to outbreaks from extrinsic factors and provision of relevant advice could prove beneficial to significant numbers of patients. Sensitive Skin. From the perspective of our research, the definition of sensitive skin is still evolving. Certain individuals may view sensitive skin as fashionable; however, clinicians and the people who work in the personal-care industry know that when certain materials are applied to the skin, some individuals report symptoms (burning, stinging, itching, a tight feeling) and sometimes show traditional signs of irritation. The reasons for sensitive skin in these individuals may be obvious, but many times the complaints and signs of irritation occur in individuals who appear to be normal. Using our ongoing work we would like to suggest that the label "sensitive skin" apply to the following four categories: 1. Those individuals with obvious skin disease. 2. Those individuals with subclinical (mild) or atypical clinical signs of disease. 3. Those individuals who have experienced past insults to the skin. 4. Those individuals who do not fit into one of the above three categories and appear to be "normal". To define sensitive skin fully we may need to perform full profiles of the skin of these patients. In addition to history and examination, a battery of noninvasive tests may be helpful.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
96.
97.
The "chemosensitizing" properties of the radiosensitizer misonidazole (MISO) were examined in 2 tumour systems, murine Lewis lung carcinoma and human pancreatic adenocarcinoma xenografted into immune-suppressed mice, using a soft-agar colony assay to measure tumour-cell survival. In mice bearing Lewis lung tumour, the administration of MISO simultaneously with melphalan, cyclophosphamide. CCNU, FU or vincristine gave substantial enhancement of cytotoxicity (DEFs from 1.5 to 3.5). However, no enhancement was seen with bleomycin, VP 16-213 or cis-Pt. The same level of enhancement of cyclophosphamide effect (DEF = 2.0) was seen with both cell survival and growth delay end-points effect (DEF = 2.0) was seen with both cell survival and growth delay end-points of tumour response. Enhancement was also seen in the human tumour xenograft with melphalan, cyclophosphamide and MeCCNU, using a cell survival assay, but cis-Pt was again not enhanced.  相似文献   
98.
We induced pancreatic adenocarcinomas in Long-Evans rats by placing crystals, 2-3 mg, of 7,12-dimethylbenz[a]anthracene (DMBA) in a 2- to 3-mm incision in the "head" of the pancreas approximately 1 cm from the duodenum. The incisions were closed with one or two silk sutures. The animals were killed 4-10 months after DMBA implantation, and nodules were removed and routinely prepared for light and/or electron microscopic study. Histologic organization varied from normal, through areas of tubule-like structures, to sheets of pleomorphic tumor cells. Electron microscopic study of tumor cells revealed large electron-lucent nuclei that frequently had irregular outlines and prominent nucleoli. The predominant feature of the cytoplasm was abundant rough endoplasmic reticulum. Zymogen granules were rare. Adjacent cells sometimes were jointed by an apical junctional complex to form a lumen into which projected irregular microvilli. A basal lamina sometimes occurred at the bases of the tumor cells. The fine structural similarity of these tumor cells to acinar cells was noted.  相似文献   
99.
100.
BACKGROUND: There are no data in the literature on pressure changes in the prostatic urethra during ejaculation. In healthy men, it has always been postulated that there must be a pressure gradient in order to prevent retrograde ejaculation, but scientific proof for that is pending. METHODS: In five healthy male volunteers, the pressure profile in the prostatic urethra was registered during ejaculation, using a 10 French balloon catheter with 16 pressure channels. The channels were arranged in pairs at 5-mm intervals, beginning just below the balloon at the bladder neck and extending down to the external urethral sphincter. RESULTS: In the proximal part of the prostatic urethra, a pressure of up to 500 cm of H(2)O was measured in all subjects. Contrary to that, pressures did not exceed 400 cm of H(2)O distally to the verumontanum. CONCLUSIONS: A novel method to register the pressure profile in the lower urinary tract during ejaculation (ejaculomanometry) is presented. This study adds to the knowledge of the normal physiology of reproductive function and may be useful in the evaluation of male sexual and reproductive disorders.  相似文献   
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