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PubMedDate not supplied

[Persistent polyclonal B-cell lymphocytosis].

Persistent polyclonal B-cell lymphocytosis (PPBL) is a rare and recently described entity. PPBL is diagnosed predominantly but not exclusively in women, usually smokers and is characterized by a moderate, chronic and absolute lymphocytosis (> 4 x 109/L). Peripheral blood examination show in all cases atypical binucleated lymphocytes. A polyclonal serum IgM is also associated and HLA-DR7 expression is present in most cases. The B cells are polyclonal with kappa and lambda light-chain expression. No clonal rearrangement of immunoglobulin heavy chain genes is observed. Finally, +i(3q) is a recurrent chromosomal abnormality and detected in 77% of cases with premature chromosome condensation in 50% and both abnormalities in 41% of cases. The benign clinical course of PPBL and lack of biological evolution in the majority of cases suggest that recognition is so important that aggressive therapy could be avoided.

B-Lymphocytes↗
PubMed1975

[A form of late propionic acidemia].

Report of 3 cases of propionic acidemia which concern one boy (O.M.) in whom a formed diagnosis of hyperglycemia with ketosis had been established, and two sisters (C.V. and K.V.) of another family. The activities of propionyl-CoA carboxylase in O.M. and C.V. fibroblasts were reduced to 4.5 and 2.5% of control. After two severe metabolic crisis, at 6 and 44 months of age, O.M. has at the present time (11yrs) a normal psychical development, and very few neurological disorders. Propionic acidemia was manifested only at 34 months of age in C.V. with a very severe crisis of acidoketosis with hypoglycemia, leading to neurological sequellae which are still important at 56 months of age. The disease was entirely latent in K.V. at 26 months, when the diagnosis was proven; it remains latent at 40 months. These case reports represent a special form of propionic acidemia with late clinical expression. Biological evolution does not seem to be affected by prolonged administration of biotine.

Acidosis↗
PubMed2002

[Cystic pancreatic tumors].

Cystic tumors of the Pancreas (CTP) are rare (less than 5% of all pancreatic tumors). We have limited our study to CTP of epithelial origin which represent 90% of all CTP. These can be divided into three subgroups: (1) Benign tumors with no risk of malignant progression (serous cystadenoma). (2) Tumors with risk of malignant degeneration (mucinous cystadenoma, intraductal papillary mucinous tumors (IPMT), and pancreatic solid-cystic papillary tumor. (3) Malignant tumors (cystadenocarcinoma, IPMT with malignant degeneration). The latter two groups of CTP require radical resection while serous cystadenoma does not require surgical intervention unless symptomatic. The ability to determine preoperatively the exact nature of a CTP is of tremendous importance; cytologic examination and biochemical assays of cyst fluid aid greatly in this determination. Better understanding of the biologic evolution of CTP has increased the indications for surgical resection but the risks of postoperative morbidity and mortality in these patients must not be underestimated.

Cystadenoma↗
PubMedDate not supplied

[Sodium reabsorption and the membrane systems of vertebrate kidneys].

Sodium reabsorption is low in coldblooded animals (the lamprey Lampetra fluviatilis, red salmon Oncorhynchus nerka, carp Cyprinus carpio, frog Rana temporaria, tortoise Agryonemis horsfieldi) being much higher in warmblooded ones (chicken, pigeon, rat). High level of Na transport in warmblooded animals is paralleled by high activity of succinate dehydrogenase as compared with the activity of Na,K-ATPase. The content of monoenoic fatty acids in the glycerophosphatides from frog and tortoise kidneys is higher than that from pigeon and rat ones.

Adenosine Triphosphatases↗
PubMed2001

Darwin, Cuvier and Geoffroy: comments and questions.

In writing, in the Origin of Species, of 'two great laws' on which organic beings are formed, 'Unity of Type' and 'Conditions of Existence', Darwin was referring to the famous opposition between Cuvier and Geoffroy Saint-Hilaire, first stated publicly in the spring of 1830. After a brief statement of the chief points at issue in the debate, I raise the question of Darwin's attitude to the disagreement and the views of the two protagonists. There are numerous earlier, and some later, references to Cuvier and Geoffroy in the Darwin archives, notebooks, marginalia and correspondence. An examination of these materials suggests a shift in Darwin's sympathies, from Geoffroy to Cuvier. However, some of Geoffroy's principles are retained, and, in adopting Cuvier's phrase 'conditions of existence', Darwin partly alters its meaning. Finally, since originally, and in its adoption by such writers as Whewell and Owen, the expression 'conditions of existence' was interpreted as entailing design or final cause, I consider the vexed question of Darwin's attitude to teleology.

Animals↗