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121.
Summary We investigated the role of urinary testosterone levels as a marker of risk of recurrent disease in 113 operable breast cancer patients (70 premenopausal, 43 postmenopausal). Twenty-four-hour urine collections for testosterone measurement were obtained before surgical treatment, between 20–40 days thereafter, and then every 6 months for 5 years. The cutoff values to separate high testosterone (A+) from normal testosterone (A–) were 8.0µg/24h in premenopause and 4.9µg/24h in postmenopause. Urinary testosterone levels were considered high when they exceeded the cutoff value in at least 2 of the first 3 measurements (pretreatment, post-treatment, 6 months) of each patient. According to the aforementioned criterion, 33 patients (29.2%) had high testosterone levels, which were associated to axillary node involvement in 16 patients. Thirteen of the latter relapsed during the 5-year follow-up period (5/7 in premenopause, 8/9 in postmenopause). Relapse-free survival (RFS) curves were drawn only for node-positive patients owning to the small number of recurrences observed in the node-negative group. In premenopausal node-positive patients, RFS was significantly different for patients presenting high and normal urinary testosterone levels (77% vs 28%, respectively; logrank test, p< 0.006). In postmenopausal node-positive patients, RFS was also different between the two groups (54% vs 11% in high and normal excretors, respectively) but the difference was not statistically significant. The present findings suggest that urinary testosterone is a prognostic indicator of early breast cancer recurrence in node-positive patients.  相似文献   
122.
Bombyx mori silk fibroin (SF) is a very versatile biopolymer due to its biocompatibility and exceptional mechanical properties which make possible its use as a functional material in several applications. SF can be modified with a large variety of chemical approaches which endow the material with tailored chemical–physical properties. Here, a systematic investigation of different routes is reported to graft long alkyl chains on SF based on both liquid- and solid-phase, aiming to modulate its hydrophobic behavior. The liquid phase method involves direct activation of SF tyrosine residues via diazo coupling and cycloaddition reactions, generating hydrophobic materials insoluble in any common solvent. The solid phase approach consists of the chemical modification of drop-casted SF films by esterification of hydroxyl groups of serine, threonine, and tyrosine SF residues with acyl chlorides of fatty acids. For the solid-state functionalization, a new class of hydrophobic pendant groups is synthesized, based on triple esters of gallic acid anhydrides, that are reacted with the biopolymer to further enhance its resulting hydrophobic features.  相似文献   
123.
In neuroblastoma, high levels of mRNA for p14h trkA and p75 LNGFR neurotrophin receptors are predictive of favorable outcome. Their evaluation by Northern blot, however, requires substantial amounts of tissue and this prevents their routine evaluation as well as the possibility for multicenter studies to be easily carried out. In an attempt to overcome these limitations, the feasibility and reliability of determining both neurotrophin receptors on cryostat sections by immunohistochemistry were assessed, and these findings were compared to those obtained from Northern blot analysis. Primary tumor samples from 28 untreated patients at all stages were evaluated by using H10 anti-p140 trkA and ME20.4 anti-p75 LNGFR mAbs. Although weak, positiveimmunostaining was found in 9 of 28 tumors for p140 trkA and in 5 of 28 tumors for p75 LNGFR . As compared to Northern blot, the concordance rate was 79% (22 of 28 cases) for p140 trkA (p < 0.05) and 71% (20 of 28 cases) for p75 LNGFR (p < 0.05). No case negative for Northern blot was found to be positive with immunohistochemistry. Since only high mRNA levels for both receptors have been shown to be clinically relevant, their immunohistochemical detection, although less sensitive than Northern blot, can be just as sufficient and reliable as a prognostic tool, and possibly with a better cost-benefit ratio.  相似文献   
124.
This paper presents evidence that L-tyrosine oxidation products and 5,6-dihydroxyindole, an intermediate of melanin synthesis bind to and modify DNA structure, as tested by extracting cell DNA, using topoisomerase I and denaturation assays. When supercoiled plasmid pCU18 or pBR322 DNAs are treated with 5,6-dihydroxyindole the supercoiled species disappear and are converted to species less mobile in a gel retardation test with respect to relaxed DNA. 5,6-Dihydroxyindole causes an easier acid denaturation of the double helix. The results, that are dose dependent,would point to both intercalation and cross-linking of DNA by 5,6-dihydroxyindole and its oxidation product(s). 3H-L-tyrosine deriving radioactivity, bound to nuclear DNA, is higher at low pH, (5.6) if compared to pH 6.8. The highest radioactivity bound to cell DNA is found during the transition from the amelanotic to the melanotic phenotype in human melanoma cell lines. As a control, the binding of 3H-L-tyrosine radioactivity to human prostate fibroblast DNA was investigated.  相似文献   
125.
Interleukin-12 (IL-12) is a disulfide-linked heterodimeric cytokine originally identified as a product of EBV-transformed B cell lines. Monocyte/macrophages are the physiologically most relevant producers of IL-12, in response to both Gram-positive and -negative bacteria, bacterial products, and intracellular parasites. Although IL-12 has an enhancing effect on the survival and growth of early hematopoietic progenitor cells, most of the IL-12 biological activity has been described on T and NK cells, on which it induces production of lymphokines, primarily IFN-, enhances cytotoxic activity, and, in cooperation with other stimuli, increases proliferation. IL-12 is an inducer of development of T helper type 1 (Th-1) cells and the equilibrium between IL-12 and IL-4 is probably important for the balancein vivo between Th-1 and Th-2 responses. IL-12 has an important role in the host resistance to infection, in particular to intracellular pathogens, by activating macrophages through induction of IFN- from NK and T cells and by enhancing cell-mediated immune responses, dependent on Th-1 cell development. Peripheral blood mononuclear cells from HIV-seropositive individuals are impaired in their ability to produce IL-12 in response to bacterial stimulation, and IL-12 restoresin vitro some of the depressed immunological functions, suggesting that a defect in IL-12 production may have a pathogenic role in the immunodeficiency of HIV-infected individuals. Natural IL-12 appears to provide a regulatory link between innate resistance and the development of the antigen-specific adaptive immune response and the recombinant protein has therapeutic potential because of its activity against tumors and infections and its effectiveness as an adjuvant enhancing cell-mediated immunity in vaccination.  相似文献   
126.
PURPOSE: This paper intends to stress the importance of early diagnosis and discuss surgical treatment of Type IV Ehlers-Danlos syndrome (EDS-4), an autosomal dominant connective tissue disease characterized by typical features of the face and extremities, inappropriate and easy bruising, and extreme tissue fragility, which may lead to dramatic and often fatal complications, mostly spontaneous arterial or intestinal rupture. METHODS: We report the case of a 41-year-old female who presented with spontaneous perforation of the sigmoid colon. RESULTS: The patient was seen over a nine-year period, during which time she required six operations and presented with a great number of surgical complications including stenosis of an end-colostomy, repeated subocclusive episodes caused by intraperitoneal adhesions, and enterocutaneous fistulas, finally ending with an ileostomy and short bowel syndrome. It is only after a difficult laparotomy for ovarian cyst excision, marked by numerous adhesions and friable bowel, that the diagnosis of EDS-4 was considered and established. CONCLUSIONS: In case of “idiopathic” spontaneous perforation of the colon in a young adult, features of EDS-4 should be thoroughly looked into and, if found, skin fibroblast culture with collagen Type III analysis performed. The surgical treatment of choice consists of subtotal colectomy and permanent endileostomy. In case of patient refusal, a second-stage ileorectal anastomosis can be performed but carries the high risk of anastomotic leakage.  相似文献   
127.
Objectives To investigate the potential advantages of epidural anesthesia in an in vitro fertilization and embryo transfer program.Study Design Between January 1991 and December 1992, 148 infertile patients underwent transvaginal ultrasound guided oocyte retrieval. A total of 44 patients (group A) had 50 retrievals under epidural anesthesia, and 104 patients (group B, control group) 112 retrievals under intravenous sedation (propofol) with mask-assisted ventilation (nitrous oxide).Results In group A satisfactory anesthesia was achieved in 49 of the 50 cases (98%); one patient required additional intravenous administration of propofol owing to extreme anxiety. No complications were observed. Adversely, in group B nausea was observed in 16 cases (14%) and nausea and vomiting in 7 cases (6%). In group A the fertilization, cleavage and pregnancy rates were 67.2%, 92% and 20% respectively, while in group B the rates were 69.3%, 93% and 19.6% respectively; the differences are not statistically significant.Conclusions Epidural anesthesia is an effective method for transvaginal oocyte retrieval but does not improve the treatment outcome as compared to an intravenous sedation with mask-assisted ventilation using propofol and nitrous oxide.  相似文献   
128.
Objectives To evaluate uterine artery resistance during multiovulation induction in relation to the implantation rate in patients attendingin vitro fertilization (IVF) cycles.Patients Multiovulation induction for IVF was monitored by daily determination of the pulsatility index (PI) of the uterine arteries, obtained by a transvaginal probe (6.5 MHz) implemented with color-flow imaging. Doppler data were obtained from 5 days before hCG administration to the day of follicular aspiration. One IVF cycle was monitored in 70 patients. In 17 patients, 41 IVF cycles were monitored until a successful attempt occurred.Results In the 70 patients studied during one IVF attempt, the PI of the uterine arteries significantly varied (P < 0.001) in the different phases of the cycle. In the 24 patients who conceived, a significantly lower PI (P < 0.03) was found throughout the cycle. This result was mainly due to a highly significant difference of PI values observed the day after hCG administration (P < 0.005). In the 17 patients who conceived after 1 to 4 negativein vitro fertilizations, no significant difference in PI was observed in the uterine artery resistance in cycles in which implantation was or was not successful.Conclusions Uterine artery resistance varies significantly during phases of the induction therapy. Uterine artery resistance is lower throughout the course of multiovulation induction in patients with higher pregnancy rates. The PI on the day after hCG administration was the best index of pregnancy rate. Low uterine artery resistance was present even in negative attempts in patients who eventually achieved a successful implantation. PI values 3 can be considered a favorable prognostic factor for future IVF cycles.Presented at the 49th Annual Meeting of the American Fertility Society, Montreal, 1993 and the 50th Annual Meeting of the American Fertility Society, November 5–10, 1994, San Antonio, Texas.  相似文献   
129.
Summary Intramuscular nerve fibres in the bladder of adult female rats were investigated by means of serial sections. The following observations were made. (1) Upon penetrating into the musculature the nerve bundles branch repeatedly, and almost all turn into single fibres; their axons become varicose, the Schwann cell sheath is attenuated, incomplete or absent, and the separation between axonal membrane and muscle cell membrane is reduced to tens of nanometres. (2) All single axons, and some of those within bundles, are varicose, but the characteristic of being varicose is expressed by degrees, and is not an all-or-none state. (3) Varicosities contain vesicles (mostly of the agranular type), microtubules (with little connection with the axolemma or the vesicles), some neurofilaments (scarce or absent in the best developed varicosities), mitochondria (whose size is on average smaller than those of the perikaryon, and a minute amount of endoplasmic reticulum. (4) Terminal varicosities, the true anatomical ending of an axon, are often devoid of Schwann cell sheath, are packed with vesicles, rarely contain microtubules or neurofilaments, and lie close to a muscle cell: the gap is often reduced to 10 nm. (5) Schwann cells accompany the axons within the muscle strands. Unlike the area of the axonal profiles, the area of glial sheath changes little along the length of the nerve fibre, except towards its end. (6) The Schwann cell sheath around a varicosity is often incomplete; the area of the axolemma thus exposed is covered by the basal lamina, and is here referred to as a window. While some varicosities have a window only a few tens of nanometres in width, others have more than one window, and some are devoid of Schwann cell altogether, so that their entire axolemma is in contact with the basal lamina. The Schwann cell never extends beyond the axon, whereas very often (and possibly always) the axon extends beyond the Schwann cell. (7) Intervaricose segments vary in length and diameter, the narrowest ones accompanying the more clear-cut varicosities. Some intervaricose segments are as small as 50 nm in diameter, contain a single microtubule and lack a Schwann cell sheath. Others, sheathed by a Schwann cell, contain a single neurofilament or no organelles at all. (8) Specialized contacts between an axon and a muscle cell (neuro-muscular junctions) are abundant and are identified by four features: the axon is a varicosity packed with vesicles; the axolemma is exposed (presence of a window); the distance between the two membranes ranges between 10 and 100 nm, mostly 30–50 nm; and the intercellular gap excludes fibrils, such as collagen, but is occupied by a single basal lamina. Any of these parameters, however, can also occur uncoupled (windows on intervaricose segments; varicosities without a window; exposed axolemma far from a muscle cell). (9) There are no direct contacts between axons. Even when they run close to each other within a bundle, they are always separated by a Schwann cell process. (10) The muscle cell membrane is concave beneath the varicosities; however, the muscle cell ultrastructural features in the region of the neuro-muscular junction are not different from those in other regions of the cell. (11) On average there is more than one neuro-muscular junction per muscle cell, and examples of muscle cells receiving multiple nerve endings from one or from two axons are picked up by the serial sections. (12) A striking feature of the bladder innervation is the variability of its ultrastructural parameters. The bladder innervation does not appear to be built on a rigid structural plan, and the notion of loose-patterned innervation is presented.  相似文献   
130.
To evaluate the prevalence and risk factors for adenomyosis,the clinical records of consecutive women undergoing hysterectomyduring a 3 year period were retrieved. Data were collected onindication for the intervention, general sociodemographic characteristicsof the patients, age at menarche, parity, abortions, and menopausalstatus at surgery. Adenomyosis was diagnosed in 332 of the 1334cases (24.9%). The condition was present in 146 of the 627 patients(23.3%) with fibroids and menorrhagia, 68 of the 265 (25.7%)with prolapse, 21 of the 98 (21.4%) with ovarian cysts, 19 ofthe 100 (19%) with cervical cancer, 31 of the 110 (28.2%) withendometrial cancer, 16 of the 57 (28.1%) with ovarian cancer,and 19 of the 77 (24.7%) with miscellaneous indications. Thesedifferences were not statistically significant (x26 = 11.14).In comparison with nulliparous women, the odds ratio was 1.3and 1.5 respectively in women with one and two births (x21 trend= 5.76, P < 0.05). No relationship was found between ageat surgery, age at menarche, indications for surgery, menopausalstatus at intervention, and presence of endometriosis. Our findingsdo not support the notion that adenomyosis is more frequentlyrelated to particular clinical conditions, and suggest thatparity may be associated with an increased frequency of adenomyosis.  相似文献   
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