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31.
OBJECT: The authors report on their 11 years' experience with embolization of cerebral aneurysms using Guglielmi Detachable Coil (GDC) technology and on the attendant anatomical and clinical outcomes. METHODS: Since December 1990, 818 patients harboring 916 aneurysms were treated with GDC embolization at University of California at Los Angeles Medical Center. For comparative purposes, the patients were divided into two groups: Group A included their initial 5 years' experience with 230 patients harboring 251 aneurysms and Group B included the later 6 years' experience with 588 patients harboring 665 aneurysms. Angiographically demonstrated complete occlusion was achieved in 55% of aneurysms and a neck remnant was displayed in 35.4% of lesions. Incomplete embolization was performed in 3.5% of aneurysms, and in 5% occlusion was attempted unsuccessfully. A comparison between the two groups revealed a higher complete embolization rate in patients in Group B compared with that in Group A patients (56.8 and 50.2%, respectively). The overall morbidity/mortality rate was 9.4%. Angiographic follow ups were obtained in 53.4% of cases of aneurysms, and recanalization was exhibited in 26.1% of aneurysms in Group A and 17.2% of those in Group B. The overall recanalization rate was 20.9%. Note that recanalization was related to the size of the dome and neck of the aneurysm. Overall incidence of delayed aneurysm rupture was 1.6%, a rate that improved in the past 5 years to 0.5%. Ten of 12 delayed ruptures occurred in large or giant aneurysms. CONCLUSIONS: The clinical and postembolization outcomes in patients treated with the GDC system have improved in the past 5 years. Aneurysm recanalization, however, is still a major limitation of current GDC therapy. Follow-up angiography is mandatory after GDC embolization of cerebral aneurysms. Further technical and device improvements are mandatory to overcome current GDC limitations.  相似文献   
32.
Jahan R  Murayama Y  Gobin YP  Duckwiler GR  Vinters HV  Viñuela F 《Neurosurgery》2001,48(5):984-95; discussion 995-7
OBJECTIVE: To report our experience in treatment of arteriovenous malformations (AVMs) using a new liquid embolic agent, Onyx (Micro Therapeutics, Inc., Irvine, CA). METHODS: Between January 1998 and May 1999, 23 patients (8 men and 15 women) were treated. The patients' average age was 40 years, with seizure being the most common presenting symptom (39%). The average Spetzler-Martin grade on presentation was 3. The average AVM volume before embolization was 14.5 cm3. RESULTS: We observed an average 63% reduction in AVM volume after 129 arterial feeders were embolized. There were four adverse events. Two patients experienced ischemia because of inadvertent occlusion of an arterial feeder. One of these patients made a full recovery, but the other patient had a permanent deficit. Two other patients experienced transient neurological deficits that resolved within 1 week of embolization. Permanent morbidity was thus 4% (1 of 23 patients). There were no deaths. Twelve patients underwent subsequent radiosurgery, and 11 patients had surgery that resulted in complete resection of their AVMs. Histopathological examinations showed mild acute inflammation in specimens resected 1 day after embolization. Chronic inflammatory changes were observed in specimens resected more than 4 days after embolization. In two patients, angionecrosis of the embolized vessels was noted. No evidence of parenchymal hemorrhage was observed in these patients, and vessel wall integrity was maintained as well. CONCLUSION: Onyx is a new nonadhesive liquid embolic agent that has been used to treat 23 patients at our institution with good results. Its nonadhesive nature and ease of use make it a promising agent in the future treatment of AVMs.  相似文献   
33.
The present study was aimed to investigate the chemopreventive effects of Solanum trilobatum (ST) extract against diethylnitrosamine (DEN)-induced hepatocarcinogenesis promoted by Phenobarbital (PB) in Wistar rats. Hepatocarcinogenesis was initiated by a single intraperitoneal injection of DEN (200 mg/kg b.w.) and promoted with PB (0.05%) in basal diet. The experimental study extended for periods of 13 and 26 weeks. Alcoholic extract of ST was orally administered for the entire experimental period after initiation along with commencement of promotion. The chemopreventive effect of ST was assessed from the incidence of nodules, drug metabolizing phase I components such as contents of cytochrome P450, cytochrome b(5), activities of NADPH cytochrome c reductase, NADH - cytochrome b(5) reductase and phase II components such as levels of glutathione, activities of UDP-glucuronyl transferase, glutathione S-transferase and gamma-glutamyl transpeptidase in the liver. Lipid peroxidation at basal and prooxidants-induced (NADPH + ADP + Fe and Ascorbate + Fe) states was assessed in the microsomes. Animals administered with ST extract evidenced significant inhibition of tumor nodular incidence in DEN + PB + ST animals compared to DEN + PB animals, with favorable alterations in the hepatic drug-metabolizing phase I and phase II components. Administration of ST inhibited basal and pro-oxidant-induced lipid peroxidation. The present result suggests the probable mediation of chemoprevention by ST against DEN-induced carcinogenesis by the modulation of drug metabolizing components in the liver of treated animals.  相似文献   
34.
To define the morphological transforming region II (mtrII) of human cytomegalovirus (HCMV), a series of subclones of the Xba I/BamHI fragment EM was constructed in vitro and tested for focus-forming activity and tumorigenicity. A 980-base-pair subclone of fragment EM was identified, and its nucleotide sequence revealed three small open reading frames (ORFs), encoding 79, 83, and 34 amino acid residues. S1 nuclease analysis of HCMV-infected cells identified several distinct early RNA species within mtrII, two of which (P1 and P2) were of particular interest, since the length of the protected DNA fragments would position the 5' end of the RNAs upstream of the open reading frames. In addition, the 980-base-pair transforming sequence revealed DNA elements capable of forming stem-loop structures. Thus the transforming mtrII domain of HCMV strain Towne contains both small open reading frames that are expressed in lytically infected cells and sequences resembling insertion-like structures that may be involved in transformation.  相似文献   
35.
36.

Objective

Routine CT for patients with acute flank pain has not been shown to improve patient outcomes, and it may unnecessarily expose patients to radiation and increased costs. As preliminary steps toward the development of a guideline for selective CT, we sought to determine the prevalence of clinically important outcomes in patients with acute flank pain and derive preliminary decision rules.

Methods

We analyzed data from a randomized trial of CT vs. ultrasonography for patients with acute flank pain from 15 EDs between October 2011 and February 2013. Clinically important outcomes were defined as inpatient admission for ureteral stones and alternative diagnoses. Clinically important stones were defined as stones requiring urologic intervention. We sought to derive highly sensitive decision rules for both outcomes.

Results

Of 2759 participants, 236 (8.6%) had a clinically important outcome and 143 (5.2%) had a clinically important stone. A CDR including anemia (hemoglobin < 13.2 g/dl), WBC count > 11 000/μl, age > 42 years, and the absence of CVAT had a sensitivity of 97.9% (95% CI 94.8–99.2%) and specificity of 18.7% (95% 17.2–20.2%) for clinically important outcome. A CDR including hydronephrosis, prior history of stone, and WBC count < 8300/μl had a sensitivity of 98.6% (95% CI 94.5–99.7%) and specificity of 26.0% (95% 24.2–27.7%) for clinically important stone.

Conclusions

We determined the prevalence of clinically important outcomes in patients with acute flank pain, and derived preliminary high sensitivity CDRs that predict them. Validation of CDRs with similar test characteristics would require prospective enrollment of 2100 patients.  相似文献   
37.
38.

Background

Cisplatin (CP) or cis-diammine dichloroplatinum (II) is a platinum based standard antineoplastic drug which is used against variety of solid tumors and neoplasms. The present study aimed to evaluate the shielding effects of rutin against CP induced testicular toxicity in rats.

Methods

28 male rats were divided into four groups. First group was given saline orally while second group received intra-peritoneal (i.p) injection of cisplatin (7 mg/kg) on day first and received saline for next 13 days. Third group received i.p injection of cisplatin at day one and treated with rutin (75 mg/kg) orally for next 13 days. Fourth group was treated with rutin orally for 13 days. Animals were sacrificed on 14th day and reproductive organs were analyzed for various parameters.

Results

Cisplatin treatment resulted in a significant decrease in daily sperm production, decrease in head length and % DNA in head, reduction of epithelial cell height, tubular diameter, reduction of the number of spermatogonia, spermatocytes and spermatids, increase in the thiobarbituric acid reactive substances (TBARS) and oxidative stress in testicular tissues, and change of the intra-testicular testosterone concentrations. Rutin co-treatment resulted in reversing cisplatin effect on DNA damage, sperm count, histological and biochemical parameters.

Conclusion

These results indicated that rutin co-treatment could ameliorate cisplatin-induced reproductive toxicity in male rats.
  相似文献   
39.
Tuberculosis of breast is an extremly rare form of extrapulmonary tuberculosis even in endemic area like Bangladesh and the incidence is 0.25-4.5% of all breast lesions. The diagnosis is difficult because of nonspecific clinical, radiological and histopathological findings. Very often biopsy specimens are inadequate and microscopy or culture is negative. It is usually suspected in a multiparous woman who may be immunocompromised. We report a case of breast tuberculosis in a 26 years old multiparous lady who previously present with two times attack of right sided breast lump and then diagnosed as a case of breast abscess and treated by incision and drainage with antibiotics in a nearby local hospital. During her third time attack she admitted into Mymensingh Medical College Hospital with right sided breast lump with multiple discharging sinuses for one month. Biopsy was taken from the lump and sinus tract and histopathological report confirmed the diagnosis as a case of tuberculosis of breast. Her X-ray chest showed tubercular lesion in lungs. So this is a case of secondary breast tuberculosis. This case highlights how difficult is the diagnosis of a case of breast tuberculosis for which the patient may require even mastectomy at very late case. So this case is reported.  相似文献   
40.
Breastfeeding is the fundamental component of child survival strategy. It significantly influences neurological development of children. The study was conducted to assess whether exclusive and prolonged breastfeeding improves children's cognitive development, including low birth weight (LBW) babies, in a developing country setting like Bangladesh. This observational study was done on a cohort of newborn infants who were discharged from the special care baby unit of Dhaka Shishu Hospital during January 2006 to December 2008 with proper counseling about exclusive and prolonged breastfeeding. Their neuro-developmental follow-up was started at 4 weeks postnatal age and continued at 3-monthly intervals up to 1 year of age. At each visit, cognitive development was assessed using the Bayley Scales of Infant Development (BSID II). Cognitive development was compared between the babies of exclusive vs. non exclusive breastfeeding, normal weight vs. low birth weight and male vs. female babies. A total of 105 cases were successfully followed-up during this period. Out of these 47(44.8%) babies were exclusively breastfed up to 6 month of age and 58(55.2%) were in nonexclusive group. Overall Psychomotor Development Index (PDI) was slightly more (108.40 ± 23.06 vs. 103.23 ± 19.87) in the exclusive breast fed babies in comparison to nonexclusive breast fed babies, but was significantly more in babies having birth weight >2.5 kg in comparison to those having birth weight of <2.5 kg. Other parameters of cognitive development were more or less same in both normal and LBW groups. Mental and motor development was same in both boys and girls. In behavior ratings, cooperation was significantly high (5.89 ± 2.54 vs. 4.71 ± 3.13, p=0.05) and vocalization (5.89 ± 1.07 vs. 4.58 ± 1.16) was also high, though not significant, in girls than boys.  相似文献   
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