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41.
Terry?O?Herndon Salvador?Gonzalez TR?Gowrishankar R?Rox?Anderson James?C?WeaverEmail author 《BMC medicine》2004,2(1):12
Background
Painless, rapid, controlled, minimally invasive molecular transport across human skin for drug delivery and analyte acquisition is of widespread interest. Creation of microconduits through the stratum corneum and epidermis is achieved by stochastic scissioning events localized to typically 250 μm diameter areas of human skin in vivo. 相似文献42.
Takasago T Goto Y Hata K Saeki A Nishioka T Taylor TW Iribe G Mohri S Shimizu J Araki J Suga H 《The Japanese journal of physiology》2000,50(2):257-265
Caffeine causes a considerable O(2) waste for positive inotropism in myocardium by complex pharmacological mechanisms. However, no quantitative study has yet characterized the mechanoenergetics of caffeine, particularly its O(2) cost of contractility in the E(max)-PVA-VO(2) framework. Here, E(max) is an index of ventricular contractility, PVA is a measure of total mechanical energy generated by ventricular contraction, and VO(2) is O(2) consumption of ventricular contraction. The E(max)-PVA-VO(2) framework proved to be powerful in cardiac mechanoenergetics. We therefore studied the effects of intracoronary caffeine at concentrations lower than 1 mmol/l on left ventricular (LV) E(max) and VO(2) for excitation-contraction (E-C) coupling in the excised cross-circulated canine heart. We enhanced LV E(max) by intracoronary infusion of caffeine after beta-blockade with propranolol and compared this effect with that of calcium. We obtained the relation between LV VO(2) and PVA with E(max) as a parameter. We then calculated the VO(2) for the E-C coupling by subtracting VO(2) under KCl arrest from the PVA-independent (or zero-PVA) VO(2) and the O(2) cost of E(max) as the slope of the E-C coupling VO(2)-E(max) relation. We found that this cost was 40% greater on average for caffeine than for calcium. This result, for the first time, characterized integratively cardiac mechanoenergetics of the O(2) wasting effect of the complex inotropic mechanisms of intracoronary caffeine at concentrations lower than 1 mmol/l in a beating whole heart. 相似文献
43.
Hiroshi Konomi Hisae Hori Junjiro Sano Hironobu Sunada Ryu-ichiro Hata Sakuhei Fujiwara Yutaka Nagai 《Pathology international》1981,31(4):601-610
Type specific rabbit antibodies to bovine type I, 11, 111, and IV (basement membrane) collagens showing no cross-reaction with other types of collagen were prepared by cross-adsorption and diethylamiuoethyl-cellulose romatography. The antibodies to bovine type I and I11 collagens showed a high cross-reaction with the corresponding human collagens, but those to type I1 and IV collagens did moderate and no cross-reactions with human type I1 and IV collagens, respectively. By using these antibodies, tissue distribution of various types of collagen in normal bovine lung was examined by indirect immunofluorescence microscopy. Both type I and I11 collagens were found to distribute widely in the interstitium of bronchial tree, bronchial
lamina propria and of interlobules as well as alveolar nipples and adventitia of pulmonary arteries. Type I1 collagen was located only in bronchial cartilage. The tissues mainly stained for type 11 collagen were the alveolar interstitium (also stained faintly for type I collagen) and the intima and media of the arteries. Type IV collagen was located in a membranous fashion in alveolar septa and bronchial smooth muscles and subepithelial layers as well as capillaries and the intima and media of arteries. ACTA PATHOL. JPN. 31: 601–610, 1981. 相似文献
lamina propria and of interlobules as well as alveolar nipples and adventitia of pulmonary arteries. Type I1 collagen was located only in bronchial cartilage. The tissues mainly stained for type 11 collagen were the alveolar interstitium (also stained faintly for type I collagen) and the intima and media of the arteries. Type IV collagen was located in a membranous fashion in alveolar septa and bronchial smooth muscles and subepithelial layers as well as capillaries and the intima and media of arteries. ACTA PATHOL. JPN. 31: 601–610, 1981. 相似文献
44.
The placenta is an important functional unit for gas transfer between mother and fetus. The placental membrane, consisting of trophoblast layer interposed between maternal and fetal blood, plays an active role for intensity of respiration, but no morphological evidence has been documented. Until now, it has been reported that fetal growth retardation and increased fetal mortality rate usually could be seen at high altitude. In an attempt to find the cause of high perinatal mortality rate in Nepal, this study was undertaken to examine pathologically about 1000 Himalayan placentas obtained in Nepal and Tibet since 1977, and the results were compared with those of 5500 Japanese placentas at Saitama Medical School since 1990. In this study, characteristics of ultrastructural features of the Nepalese placental villi investigated in recent years are reported. (1) The gross characteristics of placental pathology in the Himalayan group were represented by marked subchorionic fibrin deposits and increased chorionic cysts in contrast to low incidence of intervillous thrombosis compared with those of the Japanese group. (2) As characteristics of histological findings of the placental villi between Himalayan and Japanese groups, the incidence of chorangiosis and chorangioma in the Himalayan group was significantly higher than that in the Japanese group. (3) Accompanying an increase of vasculosyncytial membrane (VSM) in the villi, thickness and separation of basement membrane of the syncytium in addition to increased apoptosis of syncytial cell nuclei were recognized. (4) As characteristic ultrastructural features of chorionic villi of Nepalese placentas, an increase of mitochondria and cystic formation of rough endoplasmic reticulum (rER), in addition to appearance of lamellar bodies similar to alveolar epithelial type II cell in organellae of the syncytium, were observed. These ultrastructural changes of the placental villous capillaries may be ascribed to hypevascularization caused by the chronic hypoxic state. It is, therefore, presumed that trophoblast cells may play an important role for gas transfer mecha-nism under such a hypoxic state at high altitude. 相似文献
45.
Yoshifumi Nakayama Seiji Naito Masahiro Ryuto Yasuaki Hata Mayumi Ono Katsuo Sueishi Sohtaro Komiyama Hideaki Roh Michihiko Kuwano 《Clinical & experimental metastasis》1996,14(5):466-474
We developed a modifiedin vitro invasion assay system using monolayers of vascular endothelial cells. A type I collagen gel was formed in plastic dishes, and overlaid with type IV collagen. Calf pulmonary arterial endothelial (CPAE) cells were seeded onto these plates, and incubated until they reached confluence. Five human renal cell carcinoma cell lines with various metastatic potentialsin vivo were then seeded on the monolayer CPAE cells, and their colony formation and invasion activities were examined for 9 days. At day 4, the highly metastatic cell lines increased the number of colony foci on monolayer CPAE cells several fold higher than their poorly metastatic counterpart. The horizontal spreading patterns were also different between poorly and highly metastatic cell lines. On day 9, the number of carcinoma foci that penetrated the monolayer of CPAE cells and type IV collagen sheets into type I collagen gels in highly metastatic cell lines greatly increased as compared with that of poorly metastatic cell lines. Ourin vitro invasion assay using monolayer CPAE cells would be useful to evaluate protease activities and colony formation during invasion. 相似文献
46.
Hata T; Aoki S; Manabe A; Hata K; Miyazaki K 《Human reproduction (Oxford, England)》1997,12(8):1800-1804
Our purpose was to visualize normal embryonal and fetal surface anatomical
structures in the first trimester of human pregnancy by use of
three-dimensional ultrasonography with a specially developed abdominal
three-dimensional transducer. Four embryos and 31 fetuses of 8-13 weeks
gestation were studied with a specially-developed abdominal
three-dimensional transducer (3.5 MHz). This imaging system can provide
conventional two-dimensional ultrasonography images and can also generate,
within seconds, high-quality three-dimensional images in the surface and
transparent mode with no need for an external workstation. The percentage
of surface anatomical structures visualized at each gestational age
interval using two-dimensional and three-dimensional ultrasonography is
presented. Head and trunk were depicted in all cases. The number and the
clarity of visualization of face, upper and lower extremities, hand, and
foot increased with advancing gestation. The free loop of the umbilical
cord was depicted in most cases. The number of depictions of abdominal cord
insertion, midgut herniation, and yolk sac decreased with the increase of
gestation. Genitals could not be identified in the first trimester. The
ability to view some surface anatomical structures (face, hand, and foot)
was better with three-dimensional ultrasonography than with two-dimensional
ultrasonography. Three-dimensional ultrasonography provides a novel means
for visualization of surface anatomical structures of the embryo and early
fetus. These results suggest that three-dimensional ultrasonography can
become an important modality in future embryological and early fetal
research and in detection of embryonic and fetal developmental disorders in
the first trimester of pregnancy.
相似文献
47.
Common origin of the Val30Met mutation responsible for the amyloidogenic transthyretin type of familial amyloidotic polyneuropathy 总被引:3,自引:0,他引:3
48.
T. Kubo M. Kihara H. Hata Y. Misu 《Naunyn-Schmiedeberg's archives of pharmacology》1987,335(3):274-277
Summary The cardiovascular effects of selective alpha1 and alpha2 agonists and antagonists injected into the nucleus tractus solitarii (NTS) were studied in urethane-anesthetized rats. Methoxamine (0.3–3 g) injected bilaterally into the NTS caused a dose-dependent increase in blood pressure and heart rate. Phenylephrine (6 g) and an imidazolidine derivative St 587 (3 g) similarly injected also produced an increase in blood pressure, whereas a-methylnoradrenaline and an azepine derivative B-HT 920 (1 and 3 g) caused a decrease in blood pressure and heart rate. The pressor response to methoxamine (1 g) was markedly inhibited by prazosin (0.3 pg) injected into the same sites or hexamethionum (25 mg/kg, i. v.). Prazosin (0.3 g) alone injected bilaterally into the NTS did not affect the blood pressure, while yohimbine (0.1 g) similarly injected increased the pressure. These results suggest that in the rat NTS there exist alpha1 adrenoceptors responsible for an increase in arterial pressure. The NTS alpha2 adrenoceptors seem to be involved in the tonic regulation of arterial pressure.
Send offprint requests to T. Kubo at the above address 相似文献
49.
Conclusion Nous pensons que nous devons clairement préciser non seulement la distribution des branches de la v. porte, mais aussi celle des v. hépatiques drainant une tumeur afin de faciliter au mieux la résection hépatique à réaliser tout en conservant un maximum de parenchyme fonctionnel. Lorsqu'un segment doit être réséqué, il est nécessaire d'étudier la morphologie des veines et de leurs branches par phlébographie hépatique préopératoire afin de bien préciser les limites de la résection en fonction du siège de la tumeur. 相似文献
50.
Vascular anatomy of the pancreaticoduodenal region: A review 总被引:4,自引:0,他引:4
G. Murakami K. Hirata T. Takamuro M. Mukaiya F. Hata S. Kitagawa 《Journal of Hepato-Biliary-Pancreatic Surgery》1999,6(1):55-68
Vascular anatomy of the pancreaticoduodenal region has been the subject of numerous studies. However, several essential areas
of confusion remain in interpretation of the vascular configuration. We note and discuss three key points in relation to this
confusion: (1) a missing vascular arcade, (2) a rearrangement of the arcade by collateral and/or transverse vessels, and (3)
a solitary vessel without an accompanying comites vein or artery. In addition, we consider that different interpretations
as well as varying reported incidences depend on different "thresholds" when observations are made. Consideration of new aspects
of vascular anatomy of the pancreaticoduodenal region is required for further improvement of surgical procedures. In terms
of the selection of lymph node resection procedure, we discuss mainly the inferior arterial origin. Special attention should
be paid to the ligation of inferior arteries because of the high incidence of the common trunk formation of the upper jejunal
and inferior pancreaticoduodenal arteries. With regard to duodenum-preserving pancreatic head resection for benign tumors,
our observations are introduced in view of either arterial or venous configuration. First, a communicating artery between
the anterior and posterior arterial arcades is noted because of its possible critical role in blood supply to the papilla
of Vater. Second, a venous drainage route from the duodenum to the retroperitoneal space in "normal" specimens is described.
Received for publication on June 17, 1998; accepted on July 27, 1998 相似文献