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61.
62.
To examine the oxygen requirement of carbonic anhydrase-dependent sodium reabsorption in the proximal tubule, 18 anaesthetized dogs were studied under conditions of saturated distal NaCl reabsorption; the latter was accomplished by volume expansion (all groups) combined with infusion of loop diuretics (groups 1 and 3). Acetazolamide reduced HCO3- reabsorption by 602 +/- 32 mumol min-1 (55%, group 1) and by 777 +/- 103 mumol min-1 (66%, group 2). This was accompanied with a reduction in sodium reabsorption and oxygen consumption in a molar delta Na/delta O2 ratio of about 45 in both groups of dogs. The delta HCO3/delta O2 ratio averaged 16 +/- 1, which was not significantly different from the theoretical value of 18 expected for transcellular sodium transport by Na+, K+-ATPase. Mannitol (group 3) reduced NaCl reabsorption by 37 +/- 2% without affecting NaHCO3 reabsorption or oxygen consumption significantly. We conclude that carbonic anhydrase-dependent NaCl reabsorption in the proximal tubules is passive, and that NaHCO3 reabsorption is the only important active sodium transport which is sensitive to inhibition of carbonic anhydrase.  相似文献   
63.
Our experience with the surgical management of hypoplastic right ventricle with intact ventricular septum includes 26 patients with pulmonary atresia and 4 with critical pulmonary stenosis. Group 1 consisted of 8 neonates managed initially by transventricular valvotomy; 6 later required a secondary procedure, with 100% survival. Group 2 had 11 neonates managed by aorta-pulmonary artery shunting without operative death. However, only 3 have survived over the long term and 1 has required an additional shunt procedure. Group 3 had 9 infants who underwent concomitant valvotomy and shunting. There were 4 operative deaths and 1 late death. Finally, Group 4 included 2 infants managed by primary repair at 3 days and 6 days old with prosthetic enlargement of the right ventricle; 1 required the addition of a shunt. Both are alive. Seven of the 15 patients in Groups 1, 2, and 3 who survived neonatal palliative procedures have undergone reparative operations. Two had no growth of the right ventricle and underwent repair after conversion to tricuspid atresia, by a Fontan procedure. Five had prosthetic enlargement of the right ventricle in childhood with 1 late death. Findings of this review were as follows: (1) effective palliation of pulmonary atresia and intact ventricular septum or critical pulmonary stenosis with cavitary hypoplasia of the right ventricle is rare unless transventricular flow can be established; (2) establishment of transventricular flow produces a high incidence of cavitary "growth," which permits later repair; (3) the Fontan operation is available for repair in patients who have no cavitary growth; and (4) when all three portions of the right ventricular cavity can be identified by angiography, a primary repair can be performed in the neonatal period with a good long-term prognosis.  相似文献   
64.
65.
Recent studies showed that the COVID‐19 pandemic caused collateral damage in health care in terms of reduced hospital submissions or postponed treatment of other acute or chronic ill patients. An anonymous survey was sent out by mail to patients with chronic wounds in order to evaluate the impact of the pandemic on wound care. Sixty‐three patients returned the survey. In 14%, diagnostic workup or hospitalisation was cancelled or postponed. Thirty‐six percent could not seek consultation by their primary care physician as usual. The use of public transport or long travel time was not related to limited access to medical service (P = .583). In ambulatory care, there was neither a significant difference in the frequency of changing wound dressings (P = .67), nor in the person, who performed wound care (P = .39). There were no significant changes in wound‐specific quality of life (P = .505). No patient used telemedicine in order to avoid face‐to‐face contact or anticipate to pandemic‐related restrictions. The COVID‐19 pandemic impaired access to clinical management of chronic wounds in Germany. It had no significant impact on ambulatory care or wound‐related quality of life. Telemedicine still plays a negligible role in wound care.  相似文献   
66.
Porocarcinoma (synonym: malignant eccrine poroma) is a rare aggressive carcinoma type with terminal sweat gland duct differentiation. The squamous variant of porocarcinoma is even less frequent and might be indistinguishable from conventional squamous cell carcinoma (SCC). We herein describe the first case of a carcinoma presenting as a primary parotid gland malignancy in a 24-year-old male without any other primary tumor. Total parotidectomy and neck dissection were performed followed by adjuvant chemoradiation. The patient remained alive and well 10 months after diagnosis. Histology showed keratinizing SCC infiltrating extensively the parotid gland with subtle poroid cell features. Oncogenic HPV infection was excluded by DNA-based testing. NGS analysis using the TruSight RNA fusion panel (Illumina) revealed a novel YAP1-MAML2 gene fusion. This gene fusion was reported recently in a subset of cutaneous porocarcinoma and poroma. This case of poroid SCC (or squamoid porocarcinoma) adds to the differential diagnosis of SCC presenting as parotid gland tumor and highlights the value of molecular testing in cases with unusual presentation.Electronic supplementary materialThe online version of this article (10.1007/s12105-020-01181-9) contains supplementary material, which is available to authorized users.  相似文献   
67.

Although adolescents living on the street tend to have unprotected sex with many partners and substance abuse, little is known about this reality in Brazil. To estimate the prevalence and factors associated with risky sexual behavior among children and adolescents living on the street in Porto Alegre and Rio Grande. A cross-sectional study was carried out using the Respondent-Driven Sampling (RDS) sampling method to quickly and efficiently access populations of difficult access. Poisson regression with robust adjustment of variance was used in the multivariate analysis. The sample consisted of 231 participants aged 10–21 years. Most were male and aged 16- 21 years. More than half (66.7%) of the respondents did not have a school bond, and 64.5% did not live with the family. Half of the sample had been living on the street for at least four years, spending 15 h or more on the street. Most (86.6%) responded that they had already used illicit drugs in their lives, and unprotected sex prevalence was 61.9%. The variables independently associated with unprotected sex were years living on the street, hours spent on the street, having a steady partner, illicit drug use, and sexual intercourse without a condom under the influence of drugs. The high prevalence of unprotected sex points to the need for intervention policies for this population to prevent the main risk factors.

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68.
69.
Electroconvulsive therapy (ECT) was successfully used to treat a patient with large neurosurgical defects of the cranium and small pieces of shrapnel in the zygoma and neck. Other patients with a variety of skull defects have also been treated successfully. Theoretical considerations of current pathway in ECT would suggest an alteration through the brain when the skull is deformed, but this does not appear to affect clinical outcome.  相似文献   
70.
From January 1979 to October 1986, 86 patients with surgically resectable adenocarcinoma of the rectum or rectosigmoid were treated with adjuvant radiotherapy consisting of preoperative 2,400 cGy (22 patients), preoperative 4,000 cGy (14 patients), "sandwich" technique (27 patients), and postoperative irradiation (23 patients). Average follow-up was 42.9 months. The local recurrence rate was 4.5%, 9.1%, 7.4%, and 34.8%, respectively. The distant metastasis rate was 18.2%, 18.2%, 7.4%, and 30.4%, respectively. Preoperative radiotherapy with adequate surgical resection appears more effective in reducing the incidence of local recurrence.  相似文献   
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