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981.
1. The early life-history stages of Labeo calcasu (Hamilton) viz., the fries, are zooplankton-feeders (carnivorous). The morphology, anatomy and histology of the alimentary canal during this stage is adapted accordingly. 2. With increase in age, size and body-length, the food and feeding habits of the fish undergo changes from the carnivorous to the herbivorous type (adult) through the omnivorous type (fingerlung). 3. The morphology, anatomy and histology of the alimentary canal gets modified accordingly in the fingerlings and adults.  相似文献   
982.
983.
OBJECTIVE: To determine if serum inhibin concentrations are lower in ectopic (EP) versus intrauterine pregnancies (IUPs) that are conceived spontaneously. DESIGN: Case-control study. SETTING: Academic clinical practice. PATIENTS: Serum samples were obtained from 19 women who had EP confirmed at surgery and by pathology. For comparison, serum samples were collected from 24 women of similar chronological and gestational age with sonographic evidence of an IUP. MAIN OUTCOME MEASURE: Serum dimeric inhibin-A, total inhibin, P, and hCG. RESULTS: Serum total and dimeric inhibin concentrations in women with EP were < 60% of the concentrations for women with single IUPs. Total inhibin, but not dimeric inhibin-A, was elevated in maternal serum before week 8 of gestation relative to normal menstrual cycle levels. CONCLUSIONS: Serum inhibin concentrations are lower in EP as compared with IUPs that are spontaneously conceived and the relative amounts of dimeric inhibin-A, B, and alpha inhibin subunit in maternal serum may change throughout gestation.  相似文献   
984.
The establishment and characterisation of paired autologous tumour cell line (MST-1) and tumour-infiltrating lymphocyte (TIL) culture from a tumour mass of a 14-year-old Taiwanese girl with soft tissue melanoma are described. MST-1 cells grown in vitro were heterogeneous in morphology, ranging from floating round cells, loosely attached round/oval or elongated cells with prominent pseudopod-like processes, to well-attached spindle and elongated dendritic cells without obvious pseudopods. Immunostaining revealed that major melanoma-associated antigens, such as S100 protein, HMB-45, melanotransferrin, chondroitin sulphate proteoglycan, and the gangliosides GD2 and GD3, were consistently expressed by the tumour tissue, severe combined immunodeficiency (SCID) mouse xenograft and derived cell lines. Flow cytometric analysis of the tumour DNA content showed an index of 1.8 relative to normal peripheral blood lymphocyte DNA. Chromosome analysis revealed all cells at a hypotetraploid level with several clonal chromosome aberrations, including deletions at 10p and 12q, an addition at 12q, translocations t(1;14) and t(5;6). Electron microscopy showed melanosome structures. This observation and the expression of the major melanoma-associated antigens were all indicative of the melanocytic origin of MST-1 tumour. Interleukin-2 (IL-2) expanded TILs had the predominant CD8+ phenotype and the capacity to lyse cells of the cultured autologous tumour. The availability of the soft tissue melanoma cell line, the SCID mouse xenograft tumour system as well as autologous TILs described herein would provide useful materials for identifying T-cell-defined antigens as well as a model system for devising individualised cancer biotherapeutic strategies. This cell line can also be used for further studies aimed at uncovering the histogenesis of this rare cancer.  相似文献   
985.
The purpose of this study was to measure the degree of anesthesia following the administration of 3.6 ml of 2% lidocaine solutions with either 1:50,000, 1:80,000, or 1:100,000 for inferior alveolar nerve block and to compare the results with those obtained following the administration of 1.8 ml of the same solutions (1). With the use of a repeated measures design, 30 subjects randomly received an inferior alveolar injection at three successive appointments. The first molar, first premolar, lateral incisor, and contralateral canine (control) were blindly tested with an Analytic Technology pulp tester at 3-min cycles for 50 min. The degree of anesthesia was comparable for the three solutions following the administration of 3.6 ml of each solution. Retrospective evaluation showed that the volume of the solution influenced the degree of anesthesia.  相似文献   
986.
The temporal/spatial dissemination of interictal spikes among different brain structures was studied during the course of kindling to determine if the long-term dissemination pattern reflects the rate and expression of kindling. The experiments were conducted on adult rabbits with chronically implanted electrodes (dorsal hippocampus, amygdala, caudate, all bilateral, sensory motor and occipital cortices). Rabbits (n = 13) were subjected to once daily electrical stimulation in the left hippocampus. Kindling resulted in the development of two different epileptic phenomena: 7 animals quickly (in 2-3 weeks) achieved a fully kindled state, characterized by generalized seizures, whereas the remaining 6 rabbits did not reliably progress beyond partial seizures even after more prolonged stimulation. Animals were accordingly divided into two groups referred to as generalized seizure and partial seizure. The temporal/spatial dissemination pattern, particularly in the two hippocampi, was very different between the groups. In both groups interictal spiking originated in one of the hippocampi independent of site stimulated and represented formation of the primary hippocampal epileptic focus. The generalized seizure group demonstrated stability of the primary hippocampal epileptic focus with permanent predominance of spiking in it over the course of kindling, and a high level of bilateral synchronous hippocampal interictal spiking. In the partial seizure group the primary hippocampal epileptic focus was established during the first 2-3 weeks of stimulation. This was later suppressed upon the development of an independent secondary focus in the opposite hippocampus. These animals also displayed very low levels of synchronous bilateral hippocampal interictal spiking. We suggest that an antagonistic relationship can develop between mirror hippocampal epileptic foci. This can be associated with a low level of bilateral hippocampal synchronous spiking, kindling retardation, and manifestation of partial seizures.  相似文献   
987.
The 3-hydroxy-3-methylglutaric acid (HMG) containing flavonoid glucoside chamaemeloside, has been determined to have in vivo hypoglycaemic activity comparable to that of free HMG. An improved isolation scheme for obtaining chamaemeloside from Chamaemelum nobile is presented.  相似文献   
988.
989.
Though very rare compared to imported malaria, airport malaria should not be disregarded considering its very special gravity often due to late diagnosis. In most cases, it could be avoided if airlines and airports applied disinsecting measures vigilantly.  相似文献   
990.
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