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91.
Subarachnoid hemorrhage (SAH) of spinal origin is a rare entity accounting for approximately 1% of all cases of SAH. Its most frequent causes are trauma and vascular malformations. Although primary spinal tumors, especially ependymomas, are also relatively common causes, SAH secondary to a metastatic spinal tumor arising from outside the central nervous system is an extremely rare condition; only one case has been reported in the literature. The authors present a case of spinal meningeal carcinomatosis secondary to cutaneous malignant melanoma in which the patient presented with only symptoms of SAH. Although very rare, this case underscores several factors. 1) Spinal SAH due to spinal metastases should be considered in the differential diagnosis of patients with previously known malignancy. 2) Spinal SAH may manifest without paraparesis or sensory deficit. 3) Magnetic resonance imaging of the spinal cord may be important to determine the source of SAH in patients in whom four-vessel cerebral angiography demonstrates no abnormal findings.  相似文献   
92.
BACKGROUND: Adiponectin, an adipocyte-derived peptide, improves insulin sensitivity, has antiinflammatory and antiatherogenic effects, and is associated with a lower risk of ischemic heart disease (IHD) and type 2 diabetes. However, little is known about dietary predictors of plasma adiponectin concentrations in humans. OBJECTIVE: Our objective was to examine cross-sectionally the association between dietary factors and plasma adiponectin in men. DESIGN: Our study included 532 male participants of the Health Professionals Follow-Up Study who were selected as control subjects for an investigation of biological predictors of IHD. Diet, lifestyle, and anthropometric data were assessed by questionnaires. RESULTS: After multivariable adjustment, adiponectin was significantly inversely related to glycemic load (-1.3 mg/L per 1-SD increase; P = 0.02) and tended to be positively associated with total fat intake (0.7 mg/L per 0.5% of energy from fat instead of carbohydrates; P = 0.06). We also found a significant nonlinear association between plasma adiponectin concentrations and alcohol intake (P for quadratic trend = 0.01). Thus, whereas nondrinkers had mean plasma adiponectin concentrations of 16.48 mg/L, those who consumed 0.1-4.9, 5.0-14.9, 15.0-29.9, or >/=30 g alcohol/d had mean concentrations of 16.79 (P = 0.77 compared with nondrinkers), 18.97 (P = 0.02), 19.11 (P = 0.01), and 18.39 (P = 0.10) mg/L, respectively. CONCLUSIONS: Moderate alcohol intake is associated with higher adiponectin concentrations, whereas a carbohydrate-rich diet with a high glycemic load is associated with lower adiponectin concentrations in men with no history of cardiovascular disease. Although the strength of these associations was modest, our observations highlight the hypothesis that dietary factors may modulate plasma adiponectin concentrations-a potential mediator related to a reduced IHD risk.  相似文献   
93.
Clivus metastasis of squamous cell carcinoma: a rare location.   总被引:3,自引:0,他引:3  
Lung cancer is the most frequently encountered cancer in humans and commonly metastasizes to brain and bone. Metastasis to the clivus is very rare and there have been no previous reports. A 51-year-old woman was admitted to our hospital complaining of headache, and left shoulder, arm and back pain. The chest X-ray showed a left paracardiac mass measuring 4x4 cm in diameter and the thorax computed tomographic examination revealed a 4x4 cm mass in the left lower lobe, left hilar and mediastinal lymphadenopathy, and multiple lytic lesions in the thoracic vertebral bodies. Head magnetic resonance imaging showed a mass in the clivus with bony destruction. Bronchoscopic examination revealed an exophytic endobronchial lesion in the left lower bronchus lumen and a biopsy was taken from this lesion. The histopathological diagnosis was "poorly differentiated squamous cell carcinoma". A punch biopsy was taken from the clivus via the transnasal-transphenoidal route. Histopathological findings of this biopsy were similar to the primary site tumor. We report a rare case of clivus metastasis from squamous cell lung cancer.  相似文献   
94.
The aim of this study was to investigate the ocular surface disorders and tear function changes in patients with nodulo-cystic acne. Eighty-seven patients with nodulo-cystic acne vulgaris and 50 healthy subjects were included in the study. All subjects underwent full ocular examinations. Subjective ocular complaints were recorded. Corneal staining with fluorescein, tear film break-up time (BUT), and Schirmer test were applied. Abnormal tear film BUT and abnormal Schirmer scores were significantly more common in the acne group than in the control group. The tear film BUT was abnormal in 18 (20.7%) cases in the patient group and in 2 (4%) subjects in the control group (p=0.007). The mean Schirmer score was abnormal in 7 (8%) and decreased in 18 (20.7%) acne patients, and it was decreased in only 3 (6%) control subjects (p=0.005). Corneal punctuate epithelial erosions were detected in 3 (3.4%) acne patients, but not any of the control subjects. However, the difference between the groups was not statistically significant (p=0.184). Subjective ocular complaints were present in 28 cases (32.2%) in the patient group. Five (10%) subjects in the control group had such complaints (p=0.003). Tear function tests are also significantly altered in patients with nodulo-cystic acne. Our data suggest that severe acne patients should be referred to an ophthalmologist.  相似文献   
95.
INTRODUCTION: Thrombin activatable fibrinolysis inhibitor (TAFI) is a procarboxypeptidase downregulating plasmin formation, thereby causing a tendency for thrombosis development. Since, Beh?et's disease (BD) is a systemic vasculitis, which is commonly complicated by arterial and venous thrombosis, we aimed to find out plasma TAFI levels in BD, compared with healthy controls. We also searched whether plasma TAFI levels were significantly different between Beh?et's subgroups with and without thrombosis. MATERIALS AND METHODS: In this study, 105 BD patients (M/F: 64/41; mean age 36+/-1 years), followed up by Ege University Rheumatology Department were enrolled. The exclusion criteria were hemophilia, hyperlipidemia, diabetes mellitus, hepatic diseases renal failure, antiphospholipid positivity, oral contraceptive use and pregnancy. Age-and sex-matched healthy controls (n=53) were also included. Plasma TAFI levels were measured by ELISA. Since TAFI is also an acute-phase reactant, we also measured other inflammatory markers such as C-reactive protein (CRP). RESULTS: Plasma TAFI levels were significantly higher in Beh?et's patients (91.1+/-7.4 ng/ml) compared with healthy controls (14.3+/-4.5 ng/ml) (P<0.001), but there were no significant difference between the subgroups with and without thrombosis. In BD, there was no correlation between plasma TAFI levels and CRP. CONCLUSIONS: Regardless of manifest thrombosis, plasma TAFI levels in BD were significantly higher than in healthy controls. High TAFI levels might possibly contribute to the thrombotic tendency in BD. Future studies investigating TAFI gene polymorphism and functional activity are clearly needed, to clarify the exact role of TAFI in Beh?et's thrombosis.  相似文献   
96.
97.
In order to determine whether nicotine acts on corporal smooth muscle, the mechanism of its effect on strips of rabbit corpus cavernosum was studied in vitro. Rabbit corpus cavernosum muscle strips were mounted in an organ bath with modified Krebs-Henseleit solution and aerated with 95% O2 and 5% CO2. Tension was measured with isometric force transducers, and muscle relaxation was expressed as the percent decrease of precontraction induced by phenylephrine. Nicotine produced concentration dependent relaxation when preparations were precontracted by phenylephrine (10–5 M). The maximum nicotine-induced relaxation was 60.4±4.2% of the phenylephrine contraction and was not affected by indomethacin (10–5 M), Nw-nitro L-arginine methyl ester (3×10–5 M), methylene blue (10–5 M), glibenclamide (10–5 M), clotrimazole (10-6 M), tetraethylammonium (3×10–4 M), or 4-aminopyridine (10–3 M). Nicotine did not exhibit a calcium antagonizing effect. From these results, we conclude that nicotine-induced relaxation of the rabbit corpus cavernosum is not mediated by the release of nitric oxide, prostaglandins or a related substance, by the activation of potassium channels, or by the stimulation of nicotinic cholinoceptors. Further work is needed to determine the cellular mechanism(s) of the action by which nicotine acts on corporal smooth muscle.  相似文献   
98.
BACKGROUND: The mechanisms involved in the impaired gallbladder contractile response in peritonitis are unknown. The aim of this study was to determine the effect of peritonitis on the contraction and relaxation responses to different agonists in gallbladder smooth muscle in guinea pig. MATERIALS AND METHODS: Peritonitis was induced by cecal ligation and puncture (CLP) in 10 guinea pigs. Another group of 10 guinea pigs underwent a sham operation and acted as controls. Twenty-four hours after the operation, the guinea pigs were killed, and gallbladder strips were placed in organ bath. The contraction responses to KCl, carbachol, and histamine, and relaxation responses to cyclooxygenase inhibitors (indomethacin, nimesulide, and DFU) on KCl-induced contractions were recorded. RESULTS: There was no significant difference between the contractile responsiveness to KCl, but maximum contractile responses (E(max)) to carbachol and histamine were significantly reduced. Indomethacin, nimesulide, and DFU concentration dependently inhibited on KCl-induced contractions of gallbladder smooth muscle. E(max) values of indomethacin, nimesulide, and DFU were significantly reduced in the peritonitis group compared with controls (P < 0.05). The inhibitor effects of nimesulide and DFU were considerably similar, but inhibitor effect of indomethacin was significantly less than that measured for nimesulide and DFU in both control and peritonitis groups (P < 0.05). CONCLUSIONS: The contraction responses to carbachol and histamine and relaxation responses to COX inhibitors on gallbladder smooth muscle are significantly decreased by peritonitis. Although the mechanism of the decrease in contraction and relaxation responses in CLP-induced peritonitis is completely unknown, we speculate that impaired smooth muscle responses may be related to an alteration in the regulation of receptor/postreceptor excitation-response coupling and/or through changes on Ca(2+) influx.  相似文献   
99.
Surgical management of childhood bronchiectasis due to infectious disease   总被引:2,自引:0,他引:2  
BACKGROUND: The purpose of this study was to estimate operative risk and to identify indicators of adverse prognosis in patients undergoing resection for childhood bronchiectasis. METHODS: From January 1985 to February 2001, patients undergoing resection for bronchiectasis were studied. The indications for operation were failure of medical therapy in 33 patients (94.2%) and hemoptysis in 2 (5.7%). The mean duration of symptoms was 4.2 years (range, 1-9 years). Surgical treatment included lobectomy in 17 patients (48.5%), pneumonectomy in 7 (20%), lobectomy plus segmentectomy in 5 (14.2%), bilobectomy in 2 (5.7%), and segmentectomy in 4 (11.4%). RESULTS: The operative mortality rate was 2.8%, and the morbidity rate was 17.6%. The mean follow-up in 34 patients was 5.4 years (range, 1-12 years). Overall, 22 patients (64.7%) were asymptomatic after surgery. Clinical improvement was noticed in 8 patients (23.5%), and no improvement was noticed in 4 (11.7%). Complete resection resulted in a significantly better clinical outcome than incomplete resection (P <.05). CONCLUSIONS: Surgery for childhood bronchiectasis can be performed with low mortality and morbidity. Complete resection should be performed when possible.  相似文献   
100.
This study tested the hypothesis that the ventrolateral column of the midbrain periaqueductal gray (vlPAG) region mediates the hypotension and bradycardia evoked by visceral nociception. To test this, the local anesthetic lidocaine (2%; 0.5 microl) was microinjected into the vlPAG of halothane-anesthetized rats bilaterally and visceral nociception was induced 2 min later by injecting 5% acetic acid (0.5 ml) intraperitoneally. Acetic acid injection caused an abrupt fall in arterial pressure (-12.2+/-2.1 mm Hg) and heart rate (-37+/-93 bpm) lasting approximately 15 min. Lidocaine injection into the vlPAG prevented the fall in arterial pressure and heart rate completely. Cobalt chloride (5 mM; 0.2 or 0.5 microl) injection into the vlPAG also prevented nociceptive hypotension but it did not affect the fall in heart rate significantly. Lidocaine pretreatment also inhibited the depressor response caused by intramuscular formalin (5%; 0.2 ml) administration, a model of deep somatic nociception, although it did not prevent the response completely. To determine if opioid receptors mediate the response, selective mu, delta or kappa opioid receptor antagonists were microinjected into the vlPAG 5 min before intraperitoneal (ip) acetic acid administration. Naltrindole, a delta receptor antagonist, inhibited the response significantly but mu and kappa antagonists were completely ineffective. Lidocaine and naltrindole had no effect when injected into the dorsolateral PAG and did not influence cardiovascular function when injected into the vlPAG of saline treated control animals. These data support the hypothesis that the vlPAG mediates the depressor response evoked by visceral nociception and indicate that delta opioid receptors participate in the response.  相似文献   
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