基于I2C总线的高精密平流泵

文章在介绍I2C总线的接口和数据传输格式的基础上,着重论述了平流泵的工作原理和基于I2C总线的24LC02型E2PROM与89C52单片机的物理连接及读写操作过程,从而实现了其相关参数在串行存储器的存取,确保了该仪器的精确度.     

Noncirrhotic portal hypertension and nodular regenerative hyperplasia of the liver in dogs with mucopolysaccharidosis type I

Seventy six consecutive patients with T2-4, N0-1, M0 primary breast cancer (BC) received a median of 3 cycles of CMF (cyclophosphamide, methotrexate, 5-fluorouracil) regimen. Tamoxifen was concomitantly administered in patients with estrogen receptor positive (ER+) BC. Ki67 antigen was evaluated immunohistochemically in tumor specimens obtained before chemotherapy and at mastectomy. At post chemotherapy evaluation, tumor shrinkage greater than 50% was obtained in 60 patients (78.9%), 21 of them being complete responders (27.6%). As a whole, primary chemotherapy significantly decreased the number of Ki67 positive cells. More than 50% decrease in Ki67 expression was observed in 78.9% of patients attaining a clinical complete response (CR), in 44.7% of patients with partial remission (PR) and in 50.0% of non-responders, while an increase (>25%) in Ki67 expression was found in 5.3%, 18.4% and 18.7% of patients with CR, PR and non-response, respectively. Both CR and PR rates were superimposable in patients with ER+ and ER- primary BC, while the reduction in Ki67 expression was mainly found in ER+ cases. Patients with increased Ki67 expression from baseline, at the end of primary chemotherapy, had a shorter disease-free interval (70 months) with respect to patients with no change (88+ months) or decrease (87+ months), p<0. 05. To conclude, the activity of CMF + tamoxifen in primary BC does not seem superior to that expected administering CMF alone. The reduction in Ki67 expression, as a whole, correlated with clinical CR, but some individual discrepancies between tumor shrinkage and Ki67 pattern have been observed. The Ki67 reduction mainly confined to the ER+ primary BC suggests that tumor response in this subset may be linked to the reduction in proliferation activity, whereas other mechanisms such as apoptosis might be responsible for the tumor shrinkage in ER- tumors. Since the increase in proliferation activity after primary chemotherapy was associated with a greater recurrence rate and lower disease free interval, irrespective of tumor response, changes in proliferation activity after primary chemotherapy may represent a potentially available parameter that, in addition to the tumor response, can discriminate patients who would benefit from the cytotoxic treatment from patients who would not.     

Characterization of the effect of 2-deoxy-D-glucose(2-DG) on the immune system

This study was designed to characterize the effects of the metabolic stress of administration of 2-deoxy-d-glucose (2-DG, 500 mg/kg) on immune function. Male Lewis rats were exposed to one or five injections (one every 48 h) of 2-DG. Control rats received saline injections. Administration of 2-DG induced a reduction of total leukocytes in the spleen, thymus, and blood. The reduction was most prominent in animals that received five injections of 2-DG. The ratio of CD4(+)/CD8(+) in the spleen was decreased due to a significant increase of CD8(+) T-cell subpopulation. Additionally, 2-DG induced a suppression of mitogenic responsiveness and IFN-gamma production in both whole blood and spleen lymphocytes. The production of IL-1 and IL-2 was significantly reduced in the blood, but not in the spleen. Conversely, there was a significant increase in nitric oxide production in cultures of Con A-, PHA-, and LPS-stimulated splenocytes from 2-DG-injected animals compared with saline-injected controls. In blood cultures stimulated with Con A and PHA, the nitric oxide production of the group that received five injections of 2-DG was significantly higher than in the group that received one injection of 2-DG or saline. These results demonstrated that the metabolic stress 2-DG induced a downregulation of Th 1 cellular immune function in a manner similar to physical and psychological stressors. Additionally, the use of 2-DG in rats provided an important model with which to study metabolic stress.     

Low-frequency vibrations in the treatment of patients with acute maxillary sinusitis and ethmoiditis. Non-specific resistance and immunity

Effect of sodium hypochlorite disinfection of impressions on the size and quality of plaster models is studied. Twenty-minute submerging of silicone impressions in 0.5% sodium hypochlorite solution did not change their size and did not deteriorate the quality of surface and hardness of plaster models. Stomalgin impressions cannot be disinfected by sodium hypochlorite solution because of expressed destructive effect of this disinfectant on the impressions.     

Displaced intra-articular fractures of the calcaneus treated non-operatively. Clinical results and analysis of motion and ground-reaction and temporal forces

Twenty-seven patients who had a unilateral displaced intra-articular fracture of the calcaneus were managed with a cast instead of with reduction or an operation. The clinical result after a mean of six years (range, two to ten years) was excellent in five patients, good in five, fair in seven, and poor in ten. The sixteen patients who were re-examined for this study and for whom the gait was analyzed demonstrated abnormalities in ground-reaction force with regard to vertical force (F3) and temporal force factors (T2, T3, T6, and T9). Analysis of temporal and distance factors showed a trend toward a decreased proportion of single-limb support on the involved side. Three-dimensional motion analysis of the ankle and hindfoot was performed with electrogoniometers as the subject walked on a level surface, on a 10-degree side-slope, and up and down stairs. Motion was decreased in the sagittal, coronal, and transverse planes during walking on level ground and on a side-sloping surface. Significant decreases in motion in these planes were also seen during walking up and down stairs. Although these patients did not have a subsequent reconstructive operation, most had a residual functional deficit.     

Quinine for leg cramp: time to call a halt?

The MURCS association is traditionally regarded as a disorder limited to the female sex. It has been hypothesized that men displaying the combination of azoospermia, segmentation abnormalities of the cervicothoracic spine and renal anomalies may have a male analogue of MURCS. Here we describe a patient with non-obstructive azoospermia and Klippel-Feil anomaly type II and suggest that this may represent another case of 'MURCS in the male'.