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71.
PURPOSE: This study examined the association between maternal smoking before and during the first trimester of pregnancy and spontaneous abortion.

METHODS: We have been conducting a hospital-based case-control study on risk factors for spontaneous abortion in the greater Milan area. We collected information from 782 cases of spontaneous abortions and 1543 controls (women who delivered at term healthy infants).

RESULTS: With respect to never smokers, the odds ratio (OR) were 0.7 (95%, confidence interval (CI), 0.5–1.0) for women who quit smoking and 1.3 (95% CI, 1.0–1.6) for those who continued during pregnancy. Women who smoked more than 10 cigarettes/day in the first trimester were at increased risk of miscarriage, with an OR of 1.4 (95% CI, 1.0–2.1). No relationship was evident between the number of cigarettes smoked before conception and the risk of abortion. Likewise, no association emerged between paternal smoking and miscarriage. Moreover, no significant interaction or modification effect was obtained when strata of age and other major characteristics were investigated.

CONCLUSIONS: The risk of abortion associated with cigarette smoking during the first trimester of pregnancy was measurable and noticeable in this population, and accounted for 9% (95% CI, 6–13%) of all cases. The increased risk of spontaneous abortion in women smoking during pregnancy is a further reason to encourage pregnant women to quit.  相似文献   

72.
Since the advent of CT, secondary neoplastic lesions of the kidneys have been detected with increasing frequency. After reviewing a large series of cases of renal metastases, we have been able to classify the CT findings into seven major categories that are discussed and illustrated in this article. The differential diagnoses between metastatic disease of the kidneys and other lesions such as renal infarctions, renal lymphoma, and primary malignancies are also considered.  相似文献   
73.
M Carpani de Kaski  R Rentsch  S Levi    H J Hodgson 《Gut》1995,37(5):613-616
The association between corticosteroid treatment and gastric ulcer healing is controversial. The effects of corticosteroids on experimental ulcer healing in the rat were studied and the effect of coadministration of a prostaglandin E1 analogue was determined. Forty male adult rats were divided into five groups and pretreated for 10 days as follows: (a) control, (b) prednisolone (10 mg/kg), (c) prednisolone and misoprostol (300 micrograms/kg), (d) misoprostol, and (e) indomethacin (2 mg/kg) Gastric ulcer was induced by applying a cryoprobe to the serosal surface of the stomach. Healing was assessed by determining the ulcer size at three and six days. Mucosal regenerative activity at the ulcer edge was assessed by quantitating DNA synthesis in cells by immunohistochemical techniques using monoclonal antibodies to detect expression of proliferating cell nuclear antigen (PCNA) and incorporated 5-bromo-5-iododeoxyuridine (BrdU). Compared with control rats, the rate of healing and the mucosal regenerative activity were significantly reduced in rats treated with prednisolone and indomethacin (p < 0.05). Coadministration of misoprostol and corticosteroids reversed the delay in healing and the reduction in mucosal regeneration induced by corticosteroids alone. With misoprostol alone, the ulcer size and the number of epithelial cells that actively synthesised DNA did not differ from control animals. A comparison between the two immunohistochemical markers of cell proliferation showed a highly significant correlation between the two techniques (r = 0.64, p < 0.005), indicating that the simpler PCNA technique should prove valuable in assessing regeneration in experimental ulcer disease.  相似文献   
74.
Forty-six patients with clinical stage I testicular non-seminomatous germ cell tumours were followed up according to a protocol of active surveillance between 1979 and 1987. The median follow-up time was 40+ months. Thirteen patients (28%) relapsed, predominantly in retroperitoneum and/or lung. Ten of these relapses (76%) occurred within 8 months of orchiectomy. Relapses occurred in 7/35 T1 tumours and 5/10 T2 to T4 tumours. No correlation was detected between the histological type and relapse rate. Three late relapses were diagnosed at 23, 29 and 36 months. Eleven of the relapsed patients remain in prolonged complete remission after PVB chemotherapy +/- surgery; one patient, who initially refused treatment at the time of relapse, has died. Another relapsed with predominant elements of rhabdomyosarcoma intermingled with malignant teratoma in a bone metastasis. He had a partial response to PVB chemotherapy but subsequently died. Thirty-four patients (74%) did not undergo lymphography (LG) and had a higher relapse rate (11/34) than those who had LG (2/12); this was not a statistically significant difference in this small series. The policy of active surveillance is not yet the "state of the art" and should be under constant scrutiny with respect to safety and practice.  相似文献   
75.
To study different temporal components on cancer mortality (age, period and cohort) methods of graphic representation were applied to Swiss mortality data from 1950 to 1984. Maps using continuous slopes ("contour maps") and based on eight tones of grey according to the absolute distribution of rates were used to represent the surfaces defined by the matrix of various age-specific rates. Further, progressively more complex regression surface equations were defined, on the basis of two independent variables (age/cohort) and a dependent one (each age-specific mortality rate). General patterns of trends in cancer mortality were thus identified, permitting definition of important cohort (e.g., upwards for lung and other tobacco-related neoplasms, or downwards for stomach) or period (e.g., downwards for intestines or thyroid cancers) effects, besides the major underlying age component. For most cancer sites, even the lower order (1st to 3rd) models utilised provided excellent fitting, allowing immediate identification of the residuals (e.g., high or low mortality points) as well as estimates of first-order interactions between the three factors, although the parameters of the main effects remained still undetermined. Thus, the method should be essentially used as summary guide to illustrate and understand the general patterns of age, period and cohort effects in (cancer) mortality, although they cannot conceptually solve the inherent problem of identifiability of the three components.  相似文献   
76.
Bisection thresholds are approximately proportional to the separation/eccentricity of the targets. This "Weber's law" for position has been invoked over the past century. It is the separation of the reference targets, or their eccentricity which determines the threshold? In previous studies separation and eccentricity are confounded. In the present report we have pitted separation against eccentricity. Bisection thresholds were measured for stimuli presented on an isoeccentric arc, so that separation could be varied while holding the eccentricity of the test lines constant. We used a 5-fold range of separations from 2-10 deg. In this regime, the present results provide strong evidence against Weber's law. When separation is varied but eccentricity held constant, there is no Weber's law. Rather the thresholds are approximately constant. Our results suggest that the judgement of the separation of widely separated objects is similar to a distance measurement using a ruler on the cortex, in that the error of measurement is independent of the separation between objects. The results imply that when we attempt to gauge the distance between widely separated objects it is unlikely that we do so on the basis of the outputs of large spatial filters; rather it appears that we make such judgements by estimating the cortical distance which separates the targets of interest.  相似文献   
77.
S L Anacker  R P Di Fabio 《Physical therapy》1992,72(8):575-81; discussion 581-4
Vision and/or ankle somatosensory inputs often do not correlate with the position of the center of gravity. In this case, visual or somatosensory information may be in conflict with other sensory systems that convey a true sense of body orientation. The purpose of this study was to determine how conflicting visual and ankle somatosensory inputs influenced standing balance in elders with a history of falls. Forty-seven community-dwelling elders (8 male, 39 female), between 65 and 96 years of age (mean = 80.5, SD = 9.0), participated in this project. Subjects with two or more falls in the 6 months prior to study were assigned to a fall group (n = 16), whereas those with no history of falling during the same time interval were assigned to a no-fall group (n = 31). In order to remove any bias in the testing procedure, the tester was not aware of group assignments. Subjects were evaluated using a sensory organization test (SOT) for standing balance and a "Get Up and Go" test (GUGT) for general mobility. Analysis of covariance was used to evaluate the SOT scores (by group, vision, and surface condition) and the GUGT scores. Body sway is known to increase with the normal aging process, and for this reason, age was selected as a covariate. The association between the SOT total score and the GUGT score was evaluated using Spearman rank-order correlation coefficients. The results showed a significant interaction between group and surface conditions, which indicated a decreased stance duration for fallers on a compliant surface compared with the stance duration for nonfallers (adjusted mean faller stance duration = 53 seconds, SD = 42; mean nonfaller stance duration = 67 seconds, SD = 32). Subjects in the fall group also had significantly higher GUGT scores (which indicated poor mobility function) than did subjects in the nonfall group (adjusted mean faller GUGT score = 2.65, SD = 1.48; mean nonfaller GUGT score = 1.47, SD = 0.77). The Spearman correlation between total SOT scores and the GUGT scores was greater for fallers (r = -.67) than for nonfallers (r = -.44). Orientation input from the ankle appears to have greater importance for preventing falls compared with a visual reference. The SOT and GUGT may be useful in the field to establish criteria for screening elders in a fall-prevention program.  相似文献   
78.
Summary Up-to-date unsatisfactory results obtained in multimodality treatments of malignant glioma have prompted the research of new therapeutic modalities with unconventional modes of action. Lonidamine (LND) is a drug which reduces aerobic glycolytic activity in both human and experimental tumors. This effect mainly depends on the inhibition of mitochondrially-bound hexokinase (HK) which is present in large amounts in malignant cells. A Phase II study was conducted on patients with recurrent glioma; 12 patients were admitted to the study. Clinical side effects were moderate, necessitating a reduction of the dosage in only 1 case. The objective results were evaluated according to the indications of Levin. 2 responders and 3 cases of stable disease were observed out of 10 evaluable patients. The potential value of this new drug is discussed.  相似文献   
79.
The traditional algorithms (Marinelli-Quimby and MIRD) used for the absorbed dose calculation in radionuclide therapy generally assume that the mass of the target organs does not change with time. In radioiodine therapy for Graves' disease this approximation may not be valid. In this paper a mathematical model of thyroid mass reduction during the clearance phase (30-35 days) after 131I administration to patients with Graves' disease is presented. A new algorithm for the absorbed dose calculation is derived, taking into account the reduction of the mass of the gland resulting from the 131I therapy. It is demonstrated that thyroid mass reduction has a considerable effect on the calculated radiation dose. Either the model of the thyroid mass reduction or the new equation for the absorbed dose calculation depend on a parameter k for each patient. This parameter can be calculated after the administration of a diagnostic amount of radioiodine activity (0.37-1.85 MBq). Thus, thyroid absorbed dose and thyroid mass reduction during the first month after therapy can be predicted before therapy administration. The absorbed dose values calculated by the new algorithm are compared to those calculated by the traditional Marinelli-Quimby and MIRD algorithms.  相似文献   
80.
Hyaluronan (HA) hydrogels resist attachment and spreading of fibroblasts and most other mammalian cell types. A thiol-modified HA (3,3'-dithiobis(propanoic dihydrazide) [HA-DTPH]) was modified with peptides containing the Arg-Gly-Asp (RGD) sequence and then crosslinked with polyethylene glycol (PEG) diacrylate (PEGDA) to create a biomaterial that supported cell attachment, spreading, and proliferation. The hydrogels were evaluated in vitro and in vivo in three assay systems. First, the behavior of human and murine fibroblasts on the surface of the hydrogels was evaluated. The concentration and structure of the RGD peptides and the length of the PEG spacer influenced cell attachment and spreading. Second, murine fibroblasts were seeded into HA-DTPH solutions and encapsulated via in situ crosslinking with or without bound RGD peptides. Cells remained viable and proliferated within the hydrogel for 15 days in vitro. Although the RGD peptides significantly enhanced cell proliferation on the hydrogel surface, the cell proliferation inside the hydrogel in vitro was increased only modestly. Third, HA-DTPH/PEGDA/peptide hydrogels were evaluated as injectable tissue engineering materials in vivo. A suspension of murine fibroblasts in HA-DTPH was crosslinked using PEGDA plus PEGDA peptide, and the viscous, gelling mixture was injected subcutaneously into the flanks of nude mice; gels formed in vivo following injection. After 4 weeks, growth of new fibrous tissue had been accelerated by the sense RGD peptides. Thus, attachment, spreading, and proliferation of cells is dramatically enhanced on RGD-modified surfaces but only modestly accelerated in vivo tissue formation.  相似文献   
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