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41.
深静脉血栓形成(DVT)的年发病率为48-182/10万,一般估计为1/1000。DVT病死率为1%-5%,发病率和病死率与年龄密切相关。慢性疼痛、肿胀、偶尔腿部皮肤溃疡等血栓后综合征见于1/3发生过DVT的患者。血栓后综合征可出现较早,也可迟至10年才出现,总的发病率为2年23%,5年28%。患者如使用弹力加压袜至少2年以上,腿部病变的发生率可  相似文献   
42.
Our aim was to review our experience with percutaneous antegrade ureteric stent (PAUS) placement and to determine if the routinely conducted check nephrostogram on the day following ureteric stent placement was necessary. Retrospective review of patients who had undergone PAUS placement between January 2004 and December 2005 was performed. There were 83 subjects (36 males, 47 females), with a mean age of 59.9 years (range, 22–94 years). Average follow-up duration was 7.1 months (range, 1–24 months). The most common indications for PAUS placement were ureteric obstruction due to metastatic disease (n = 56) and urinary calculi (n = 34). Technical success was 93.2% (96/103 attempts), with no major immediate procedure-related complications or mortalities. The Bard 7Fr Urosoft DJ Stent was used in more than 95% of the cases. Eighty-one of 89 (91.0%) check nephrostograms demonstrated a patent ureteric stent with resultant safety catheter removal. Three check nephrostograms revealed distal stent migration requiring repositioning by a goose-snare, while five others showed stent occlusion necessitating permanent external drainage by nephrostomy drainage catheter reinsertion. Following PAUS placement, the serum creatinine level improved or stabilized in 82% of patients. The serum creatinine outcome difference between the groups with benign and malignant indications for PAUS placement was not statistically significant (p = 0.145) but resolution of hydronephrosis was significantly better (p = 0.008) in patients with benign indications. Percutaneous antegrade ureteric stent placement is a safe and effective means of relief for ureteric obstruction. The check nephrostogram following ureteric stent placement was unnecessary in the majority of patients.  相似文献   
43.
Idiopathic thrombocytopenic purpura (ITP) is an autoimmune disorder, occurring predominantly in women. We studied by flow cytofluorimetry the T cell subsets in men and women with ITP and compared them with healthy sex-matched volunteers. In healthy controls, women were found to have higher proportions of T helper/inducer (Th/i) and lower T suppressor/cytotoxic (Ts/c) lymphocytes and consequently higher Th/i:Ts/c ratios than men. Accordingly, in clinical surveys, patients and controls should be matched for sex for proper comparisons. In patients with ITP in its active phase, an imbalance in T cell subsets was found in both sexes. The perturbation was more severe in women who had a marked decrease in number and proportion of Th/i lymphocytes and an increase in the proportion of Ts/c lymphocytes, whereas in men only, the proportion of Th/i lymphocytes was decreased. When patients with active disease were compared to those with ITP in remission, the decrease in Th/i subsets still persisted in both sexes but the Ts/c subset in women had returned to normal proportions. Therefore, the immune imbalance in ITP is more marked in women than men; imbalances in both Th/i and Ts/c are present in women while Ts/c appears not to be involved in men.  相似文献   
44.
45.
c-kit expression in human megakaryoblastic leukemia cell lines   总被引:1,自引:0,他引:1  
Hu  ZB; Ma  W; Uphoff  CC; Quentmeier  H; Drexler  HG 《Blood》1994,83(8):2133-2144
  相似文献   
46.
47.

Background

Persistent complaints are very common after a lateral ankle sprain.

Aim

To investigate possible associations between structural abnormalities on radiography and MRI, and persistent complaints after a lateral ankle sprain.

Design and setting

Observational case control study on primary care patients in general practice.

Method

Patients were selected who had visited their GP with an ankle sprain 6–12 months before the study; all received a standardised questionnaire, underwent a physical examination, and radiography and MRI of the ankle. Patients with and without persistent complaints were compared regarding structural abnormalities found on radiography and MRI; analyses were adjusted for age, sex, and body mass index.

Results

Of the 206 included patients, 98 had persistent complaints and 108 did not. No significant differences were found in structural abnormalities between patients with and without persistent complaints. In both groups, however, many structural abnormalities were found on radiography in the talocrural joint (47.2% osteophytes and 45.1% osteoarthritis) and the talonavicular joint (36.5% sclerosis). On MRI, a high prevalence was found of bone oedema (33.8%) and osteophytes (39.5) in the talocrural joint; osteophytes (54.4%), sclerosis (47.2%), and osteoarthritis (55.4%, Kellgren and Lawrence grade >1) in the talonavicular joint, as well as ligament damage (16.4%) in the anterior talofibular ligament.

Conclusion

The prevalence of structural abnormalities is high on radiography and MRI in patients presenting in general practice with a previous ankle sprain. There is no difference in structural abnormalities, however, between patients with and without persistent complaints. Using imaging only will not lead to diagnosis of the explicit reason for the persistent complaint.  相似文献   
48.
Riley  J; Mandel  HG; Sinha  S; Judah  DJ; Neal  GE 《Carcinogenesis》1997,18(5):905-910
Activation of ras proto-oncogenes occurs frequently in vivo in chemically induced rodent tumours, including rat hepatomas induced by aflatoxin B1. This study examines the in vitro activation of a human ras gene by this mycotoxin. A plasmid containing the human Ha-ras proto- oncogene, together with a neomycin resistance gene (pECneo), was incubated in vitro with a microsomal system generating aflatoxin B1 8,9- epoxide. Subsequent transfection of the plasmid into mouse NIH 3T3 fibroblasts, followed by G418 selection and s.c. injection of surviving cells into immunodeficient mice demonstrated that the proto-oncogene had acquired transforming capacity. Although a single tumour resulted from similar treatment of incubated unconjugated plasmid, no tumours were produced by a secondary round of transfections using DNA from this tumour. Selective PCR amplification of the human Ha-ras gene in extracted tumour DNA followed by sequencing demonstrated the presence of G-->T transversions either at the first or middle base of codon 12 in tumours resulting from transfection with the aflatoxin-B1-modified pECneo plasmid, but this was not detected in the single tumour resulting from transfection with the unmodified plasmid. Thus, although a mutation in the Ha-ras gene has not been reported for human primary hepatomas occurring in aflatoxin-exposed populations, metabolically activated aflatoxin B1 is capable of mutating this proto-oncogene to its oncogenic form in vitro. No mutations were observed in codon 61. It appears that, in contrast to the frequently reported G-->T transversions in codon 249 of the p53 gene in primary hepatomas in aflatoxin-exposed humans, the failure to detect Ha-ras mutations in these tumours is not due to an inability of aflatoxin B1 to activate this proto-oncogene. The G-->T transversions observed in this study contrast with the most frequent aflatoxin B1 in vivo induced mutations, G-->A transitions in the rat Ki-ras gene. Possible mechanisms for these differences are discussed.   相似文献   
49.
The cardinal features of Kabuki (Niikawa-Kuroki) syndrome (KS) include characteristic facial dysmorphic features, mild to moderate mental deficiency, skeletal abnormalities, dermatoglyphic abnormalities, and postnatal growth retardation. We identified 8 patients with KS in a genetics clinic over the past 5 years. All were Caucasians, except for 2 who were of mixed Aboriginal and Caucasian descent. All had the facial gestalt, the dermatoglyphic abnormalities characteristic of the syndrome, and developmental delay. Dental abnormalities of permanent teeth were seen in all 8 cases; 6 had missing lower incisors. Five patients had uniquely abnormal upper incisor teeth shape; the upper incisors had a 'flat head' screwdriver-shaped appearance. Other dental abnormalities included missing lower lateral incisors, missing second premolars, and ectopic upper 6-year molars. We believe the presence of the unique dental findings will prove useful in the diagnostic assessment of individuals with KS.  相似文献   
50.
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