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51.
The common cytokine receptor gamma chain (gamma(c)) is an essential receptor component for IL-2, IL-4, IL-7, IL-9 and IL-15, and thereby gamma(c)-deficient mice exhibit impaired T cell and B cell development. The Janus family tyrosine kinase 3 (Jak3) is known to be associated with gamma(c), and the reported phenotypes of gamma(c)-deficient (gamma(c)(-)) and Jak3-deficient (Jak3(-)) mice are similar, indicating that Jak3 is an essential transducer of gamma(c)-dependent signals. Nevertheless, certain differences have been suggested related to the range of actions of gamma(c) and Jak3. To clarify whether gamma(c)-dependent cytokines can partially transduce their signals without Jak3, we compared lymphocyte development in gamma(c)(-), Jak3(-), and gamma(c) and Jak3 double-deficient (gamma(c)(-)Jak3(-)) mice in the same genetic background. With the exception that T and B cells in Jak3(-) mice express high levels of gamma(c), the defects in thymocyte and peripheral T cell and B cell development are indistinguishable among gamma(c)(-), Jak3(-) and gamma(c)(-)Jak3(-) mice. Interestingly, although Bcl-2 induction was previously suggested to be Jak3-independent, IL-7 cannot induce Bcl-2 expression in CD4 single-positive (SP) thymocytes in either gamma(c)(-) or Jak3(-) mice nor can IL-7 rescue CD4 SP thymocytes from dexamethasone-induced cell death in gamma(c)(-) or Jak3(-) mice. These results indicate that Jak3 is absolutely essential for gamma(c)-dependent T cell and B cell development, and for gamma(c)-dependent prevention of thymocyte apoptosis.  相似文献   
52.
OBJECTIVE: Transurethral enucleation of the prostate (TUE) is designed for complete removal of the prostate lobes. On the basis of TUE and holmium laser enucleation of the prostate, we developed a new technique of transurethral detachment prostatectomy (TUDP) using a tissue morcellator. MATERIALS AND METHODS: In TUDP, enucleation is performed with a prostate-detaching blade and the tip of a resectoscope, followed by removal of the tissue with a morcellator. This study reports our experience with TUDP in which the weight of retrieved tissue was greater than 30 g in 76 patients with benign prostate hyperplasia. RESULTS: The mean preoperative total prostate and adenoma volumes were 70.7 and 47.4 mL, respectively. The mean times required for enucleation, morcellation, and total operation time were 28.5, 14.4, and 66.3 minutes, respectively. The mean weight of removed prostate tissue was 61.1 g. The mean decreases in the levels hemoglobin and serum sodium were 1.73 mg/dL and 2.41 mEq/dL, respectively. The mean preoperative maximum flow rate (Qmax), International Prostate Symptom Score (IPSS), and quality of life score (QOL) improved from 9.8 mL/sec, 20.2, and 4.9, to 22.3 mL/sec, 3.1 and 1.2, respectively. Complications included mild morcellator-induced mucosal injury in 2 patients (2.6%), nausea in 4 patients (5.2%), transient urinary retention in 2 patients (2.6%), transient urge incontinence in 5 patients (6.4%), and urethral stricture in 2 patients (2.6%). The mean prostate volume and serum prostate-specific antigen level measured 6 months postoperatively in 46 patients were 10.68 mL and 0.89 ng/mL, respectively. CONCLUSIONS: TUDP is effective for complete removal of large prostate lobes in patients with large benign prostate hyperplasia and is associated with lower perioperative morbidity.  相似文献   
53.
We established a murine monoclonal antibody (K1H8) to human papillomavirus (HPV) using alkaline-disrupted virions of HPV type 1 (HPV-1) as the immunogen. K1H8 recognized a 57 kD capsid protein of HPV-1 and detected the antigen in paraffin sections of formalin-fixed tissue. With K1H8, we examined immunohistochemically 68 biopsy specimens obtained from the female genital tract. The specimens were histologically condyloma acuminatum or koilocytotic lesions with or without dysplasia and each specimen was found to harbour a single type of genital HPV, such as types 6, 11, 16, 18, 31, 33, 42, 51, 52, 56, and 58, by Southern blot hybridization analysis. The antigen was localized in the nuclei and occasionally in the cytoplasm of squamous cells showing koilocytotic changes. Eighty-four per cent of the specimens (57 cases) showed positivity for the antigen, indicating that K1H8 is a broadly-reactive antibody to various genital HPVs. The results suggest that benign mucosal lesions of the female genital tract are more frequently associated with viral production and are a potential source of transmission.  相似文献   
54.
Summary.  Comparison of the whole p30 (CA) sequence between B-tropic WN1802B murine leukemia virus and its NB-tropic derivative revealed a single base change at the 313th nucleotide. We constructed hybrid proviruses differing only at the 313th nucleotide of p30 along the whole genome, and examined the host range of the produced viruses. The single point mutation in p30 was found sufficient for the B to NB tropism conversion. Received February 19, 1997 Accepted April 18, 1997  相似文献   
55.
56.
Archival tissues are a bountiful resource for various studies. Polymerase chain reaction permits the use of such tissues for molecular biological analyses of disease causation. However, a comprehensive study using a large number of decades-old samples (20 or more years) for molecular oncology/epidemiology has never been shown to be feasible. We have relied upon the unique tumor registry of atomic bomb survivors to show that such studies are possible using 275 hepatocellular carcinoma and 41 skin cancer cases. We used 23 relatively recent thyroid papillary carcinoma cases from persons living in the vicinity of the Chernobyl nuclear reactor accident for comparison. Degradation of DNA is severe in autopsy hepatocellular carcinoma samples but can be compensated for by decreasing the polymerase chain reaction product size. Increasing the amount of DNA that is used by a factor of 8 improved amplification efficiency from approximately 60 to 80%. Age of the samples was not as great a problem as was the source of procurement. The extracted DNA can be used for all types of assays that require polymerase chain reaction amplification, such as restriction fragment length polymorphism, single-strand conformation polymorphism, and direct sequencing.  相似文献   
57.
The efficacy, safety, and pharmacokinetics of bisoprolol were investigated following oral administration once daily for 12 weeks in hyperreninemic patients with dialysis-refractory hypertension. Mean blood pressure rapidly fell from 132 to 112 mmHg in the 5.0-mg/day (n = 6) and from 142 to 128 mmHg in the 2.5-mg/day patients (n = 5), which were accompanied by a fall in plasma renin activity. On nondialysis days, Cmax and T1/2 were significantly higher in patients than in healthy control subjects. However, Cmax in the 2.5-mg/day patients was almost equal to that in healthy control subjects receiving 5.0 mg/day of bisoprolol. Plasma bisoprolol was dialyzable. During the course of the study, dialysis hypotension and bradycardia occurred in two patients receiving 5.0 mg/day of bisoprolol. In conclusion, a daily dose of 2.5 mg bisoprolol seems to be an adequate and relatively effective dose in our patients with dialysis-refractory hypertension.  相似文献   
58.
Among 300 patients receiving blood and/or blood products because of blood disorders, 3 (1%) were positive for HIV by ELISA. However, 3 patients were thought to be false positive because they had received bolus injection of gamma-globulin and their serum became negative after 6 months. Moreover, no viral inclusion or HIV-antigen was detected. In 30 patients with hemophilia and related disorders, 21 (70%) were positive by ELISA, Immunofluorescence, Passive-agglutination and Western Blot method. Immunodeficiency, as reflected by decreases of CD 4/8 ratio and NK activity, was successfully treated with high-dose of Stronger Neo-Minophagen C.  相似文献   
59.
A full-length cDNA encoding a novel protein was isolated and sequenced from a human placental cDNA library. This cDNA consists of 1735 base pairs and has a predicted open reading frame (ORF) encoding 354 amino acids. It possesses a putative signal sequence, a long extracellular domain, a transmembrane region, a short intracellular domain, and no catalytic domain, which is highly homologous to signal-regulatory protein (SIRP)-β, suggesting that it seems to be a new member of the SIRP family. Polymerase chain reaction (PCR)-based mapping with both a monochromosomal hybrid panel and radiation hybrid cell panels placed the gene to human chromosome 20p13 near the marker D20S906. Received: August 11, 2000 / Accepted: September 21, 2000  相似文献   
60.
Fascicular arrangement of the human brachial plexus is examined on 2 common cases and 3 peculiar cases in which a communicating branch was observed between the median and the musculocutaneous nerve. The musculocutaneous nerve consitss of spinal nerves from C.5, 6 and 7. The branch to the coracobrachialis receives its fibers from C.7 before it leaves the musculocutaneous nerve in 3 cases and after it leaves the musculocutaneous nerve in one case. In one case, C.7 does not send a branch to the coracobrachialis. The median nerve arises by two roots, one from the lateral cord, and the other from the medial cord of the brachial plexus. In a case in which a communicating branch was observed from the median nerve to the musculocutaneous, the fibers from C.7 join to the median nerve via the medial cord. Thus the median nerve involved all elements of the spinal nerve from C.5 to T.1. The elements of the median and the musculocutaneous nerves, therefore, are not affected by appearance of the communicating branch. The communicating branch between the median and the musculocutaneous nerves, consists of the fibers arose from C.5 and C.6, in all examined cases.  相似文献   
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