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41.
Stromal cells in the lamina propria of the human oviduct mucosa are unique cells that can differentiate into decidual cells during ectopic pregnancy in the oviduct. The nature of stromal cells is still unknown. In the present study, we investigated human oviductal stromal cells with transmission electron microscopy and immunohistochemistry and revealed that they had ultrastructural features similar to myofibroblasts and expressed alpha-smooth muscle actin, a marker used to identify myofibroblasts. Primary cilia were also one of the characteristic profiles of the stromal cells. These findings showed that the connective tissue-stromal cells in the human oviduct mucosa are myofibroblasts. They are considered to play an important role in the transport of oocytes by bringing about contraction of the mucosal folds.  相似文献   
42.
Dopamine exerts numerous actions on the kidney but the precise location of its receptor subtypes along the nephron is unknown. Using a microassay we determined the specific binding of 125I-Sch 23982, a specific and selective dopamine-1 (DA1) receptor antagonist, to microdissected glomeruli and tubule segments. Binding of 125I-Sch 23982 in the proximal convoluted tubule (PCT) was timeand concentration dependent, saturable and reversible. The linear Scatchard plot of saturation experiments suggested binding to a single site with an apparent K d of 16.7 nM and B max of 0.4 fmol·mm–1 in the PCT, and 6.2 nM and 0.1 fmol·mm–1 in the cortical collecting tubule (CCT). Mapping of DA1 binding sites along the nephron revealed their presence in each of the segments examined, albeit in markedly different concentrations: the highest specific binding was measured in PCT followed by the pars recta. Binding was less in the distal nephron, and least in the medullary and cortical thick ascending limb. Modest binding was also detected in glomeruli. In cortical collecting tubules competition studies with unlabeled dopamine and probes for DA1 (Sch 23390, fenoldopam), DA2 (domperidone, S-sulpiride), serotonergic (serotonin, ketanserin, mianserin), and -(phentolamine) and -(propranolol) adrenergic receptors indicated a rank-order potency for displacement of 125I-Sch 23982 binding, consistent with labeling of DA1 receptors. Dopamine inhibited Na/K-ATPase both in PCT and CCT, an effect duplicated in the latter segment by the DA1 agonist fenoldopam, and blocked by the DA1 antagonist Sch 23390. These results demonstrate specific DA1 binding sites in a nonhomogeneous pattern along the entire nephron, and suggest that dopamine may exert its effect on Na transport in distal as well as in proximal nephron segments.  相似文献   
43.
44.
The effect of noradrenaline (NE) on rat islet -cells was examined. NE reduced insulin secretion from rat islets exposed to extracellular solutions containing glucose at 5.5 or 16.6 mM. In islets treated with pertussis toxin (PTX), however, NE increased insulin secretion. The NE-induced augmentation of insulin secretion was inhibited by prazosin. In intact islets, NE increased phospholipase C (PLC) activity, an effect that was prevented by treatment of islets with U-73122. NE elevated intracellular [Ca2+] ([Ca2+]i) in isolated -cells independently of PTX. Although this NE effect was inhibited by prazosin, phenylephrine did not mimic it. The [Ca2+]i response to NE was also prevented by the treatment of cells with U-73122. NE produced depolarization of -cells followed by nifedipine-sensitive action potentials. NE reduced the whole-cell membrane currents through ATP-sensitive K+ channels (KATP), responsible for the depolarization. This NE effect was prevented by treatment of -cells with U-73122 or BAPTA/AM. Although at least some of our results imply the presence of 1-adrenoceptors, -cells were not stained by a polyclonal IgG antibody recognizing all adrenergic 1-receptor subtypes so far identified. These results suggest that an interaction of NE with an unknown type of receptor activates rat islet -cells via a PLC-dependent signal pathway. This effect is, however, masked by the inhibitory action via a PTX-sensitive pathway also activated by NE.  相似文献   
45.
An 18-year-old woman with abdominal pain was diagnosed as having splenic cysts by computed tomography scan. She had high serum levels of CA19-9 (2886.8 U/mL; normal value, <35 U/mL), CA125 (131.1 U/mL; normal value, <35 U/mL) and soluble IL-2 receptor (1490 U/mL; normal range, 220-530 U/mL). The resected spleen weighed 1050 g, was 14 x 28 cm, and had more than 10 macroscopic cysts up to 10.3 x 9.5 cm. There were numerous microscopic cysts in the spleen and several on the splenic capsule. The levels of CA19-9 and CA125 in the cyst fluid were 2165550 U/mL and 160400 U/mL, respectively. After the surgery, the serum levels of the tumor markers decreased gradually. The inside of the largest cyst was mainly covered by granulation tissue with a focal lining of epithelial cells, and the other macroscopic cysts had stratified squamous epithelium. The microscopic splenic cysts and cysts on the splenic capsule were lined by either attenuated single-layered or multilayered epithelial cells. The lining epithelial cells of these cysts were positive for epithelial membrane antigen and cytokeratins. CA19-9 and CA125 were detected in the lining cells of the splenic cysts. In the present case, it is suspected that the splenic cysts were derived from the capsular lining cells that showed migration from the capsule or formed microcysts on the splenic capsule, as in the case of ovarian inclusion cysts.  相似文献   
46.
In order to obtain more information on the in vitro transformationof human cells, a human fetal tracheal epithelial cell line(FHET16/5) was exposed for a long time to diethylnitrosamine(DEN). In 20 passages, this cell line (diploid, male) maintainedstrong immunohistochemical reactivity for carcino-embryonnicantigen and wool merokeratin; it was negative for vimentin.The cells contained PAS-positive mucous substances and ultrastructurallywere found to have desmosomelike attachments. Treatment of thecells was with 0.3% dimethyl sulphoxide (DMSO), or DMSO with150, 450, 1000 or 2000 µg/ml of DEN. It was started atthe ninth passage and continued for six passages over 9 weeksfor the control (DMSO) and the three lowest control doses ofDEN, and for three passages over 9 weeks for the 2000 µg/mlDEN group. Cells grown for 13 days after the end of treatmentwere plated in soft agar and injected subcutaneously in nudemice. The frequency of anchorage-independent colonies grownin soft agar was directly related to DEN dose. Colony-formingefficiency, as an expression of toxic effect, was also dosedependent. Autoradiographically detected unscheduled DNA synthesisindicated an association between anchorage-independent transformationand DNA alterations induced by DEN. Cells injected into nudemice did not produce tumours during a 6-month period, but invasivenesswas observed when cells from the 2000 µg/ml DEN groupwere transplanted on the dermis of cultured chick embryo skin.The results indicate that DEN causes anchorage-independent transformationaccompanied by unscheduled DNA synthesis in a fetal human trachealepithelial cell line.  相似文献   
47.
Summary The effect of procaine on the contractile responses to acetylcholine, substance P and KCl was investigated using the isolated guinea-pig taenia caecum. In normal Tyrode solution (37°C), procaine (10–100 mol/l) caused a parallel shift to the right of only the dose-response curve of acetylcholine (pA2 value, 5.11). The pA2 value of procaine against acetylcholine was not significantly affected by increasing the Ca concentration in the bathing solution from 0.9 to 7.2 mmol/l. On the other hand, a high concentration of procaine (10 mmol/l) caused a transient contraction of the taenia caecum, but completely suppressed contractions to all concentrations of the agonists. In K-depolarized preparations, procaine (1–10 mmol/l) shifted the dose-response curve for the CaCl2-induced contraction to the right. Substance P (3 mol/l)-induced contraction of the taenia caecum incubated with Ca-free EGTA (0.1 mmol/l) solution (20°C) was markedly reduced by procaine (10 mmol/l). Using the single sucrose-gap technique, it was found that procaine (10 mmol/l) produced a membrane depolarization and increases in both amplitude and frequency of spontaneous spike discharge. These potential changes were still observed even after the procaine-induced contraction had disappeared. The spike discharges and contraction caused by procaine were abolished in the presence of a Ca-entry blocker, verapamil (10 mol/l). From these observations, it is concluded that at low concentrations procaine acts as a competitive antagonist of muscarinic receptors in the guinea-pig taenia caecum while high concentrations of procaine may depress the contractile responses to acetylcholine, substance P and KCl by inhibiting the Ca-induced Ca release from the intracellular store site or by reducing the transmembrane Ca influx during depolarization.  相似文献   
48.
Purpose

Intravesical bacillus Calmette–Guérin (BCG) is the standard of care for bladder carcinoma in situ (CIS). The response to BCG therapy against CIS is generally assessed by random bladder biopsy (RBB). In this study, we examined the necessity of routine RBB after BCG therapy.

Methods

We retrospectively identified 102 patients who were initially diagnosed with CIS with or without papillary tumor and received subsequent 6–8-week BCG therapy. Thereafter, all patients underwent voiding cytology analysis, cystoscopy, and RBB to evaluate the effects of BCG therapy. We evaluated the association between clinical parameters (voiding cytology and cystoscopy findings) and the final pathological results by RBB specimens.

Results

According to the pathological results of RBB, 30 (29%) patients had BCG-unresponsive disease (remaining urothelial carcinoma was confirmed pathologically) and 20 were diagnosed with CIS. Positive/suspicious voiding cytology and positive cystoscopy findings were well observed in patients who had BCG-unresponsive disease compared with their counterparts (p?=?0.116, and p?<?0.001, respectively). The sensitivity (Sen.), specificity (Spe.), positive predictive value (PPV), and negative predictive value (NPV) of voiding cytology were 50%, 68%, 39%, and 77%, respectively. The values for cystoscopy findings were as follows: Sen.: 87%, Spe.: 57%, PPV: 46%, and NPV: 91%. The values for their combination (having either of them) were as follows: Sen.: 100%, Spe.: 44%, PPV: 43%, and NPV: 100%.

Conclusion

RBB after BCG therapy for patients with negative voiding cytology and negative cystoscopy may be omitted because their risk of BCG-unresponsive disease is significantly low (NPV: 100%).

  相似文献   
49.
BackgroundPortal vein embolization before liver resection is considered the therapy of choice for patients with inadequate future liver remnants. The concept of radioembolization with Yttrium-90 to achieve the same goal has limited data.MethodsWe retrospectively compared patients who underwent portal vein embolization and Yttrium-90 lobectomy before resection of hepatocellular carcinoma in patients with chronic liver disease.ResultsSeventy-three patients underwent portal vein embolization and 22 patients underwent Yttrium-90. Forty-seven percent of patients before portal vein embolization required additional procedures for tumor control, and 27% of patients after Yttrium-90 required additional procedure to mainly induce further hypertrophy. Both therapies achieved the goal of future liver remnants >40%, but the degree of hypertrophy was significantly higher in Yttrium-90 patients (63% for Yttrium-90, 36% for portal vein embolization, P < .01). Tumor response was significantly better with Yttrium-90, achieving complete response in 50% of patients. Resectability rate was higher after portal vein embolization (85% for portal vein embolization, 64% for Yttrium-90, P = .03). Tumor progression was the most common reason precluding surgery. Complete tumor control was the reason not to pursue surgery in 18% of patients after Yttrium-90.ConclusionBoth preoperative portal vein embolization and Yttrium-90, increases liver resectability rates by inducing hypertrophy of future liver remnants in patients with hepatocellular carcinoma and chronic liver disease. Yttrium-90 lobectomy achieved better tumor control and provided more time to assess therapy response, optimizing the indication for surgery.  相似文献   
50.
This study aimed to research the post-treatment quality of life (QOL) between radiotherapy (RT)- and operation (OP)-treated early cervical cancer survivors, using separate questionnaires for physicians and patients. We administered an observational questionnaire to patients aged 20–70 years old with Stages IB1–IIB cervical cancer who had undergone RT or OP and without recurrence as outpatients for ≥6 months after treatment. We divided 100 registered patients equally into two treatment groups (n = 50 each). The average age was 53 and 44 years in the RT and OP groups, respectively. The RT group included 34 and 66% Stage I and II patients, respectively, whereas the OP group included 66 and 34% Stage I and II patients, respectively. The OP group included 58% of patients with postoperative RT. Combination chemotherapy was performed in 84 and 48% of patients in the RT and OP groups, respectively. On the physicians’ questionnaire, we observed significant differences in bone marrow suppression (RT) and leg edema (OP). On the patients’ questionnaire, significantly more patients had dysuria and leg edema in the OP group than in the RT group, and severe (Score 4–5) leg edema was significantly higher in the post-operative RT group than in the OP only group. The frequency of sexual intercourse decreased after treatment in both groups. On the patients’ questionnaire, there were no significant differences between the two groups regarding sexual activity. These findings are useful to patients and physicians for shared decision-making in treatment choices. The guidance of everyday life and health information including sexual life after treatment is important.  相似文献   
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