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1.

Background  

Genes involved in dopaminergic neurotransmission have been suggested as candidates for involvement in smoking behavior. We hypothesized that alleles associated with reduced dopaminergic neurotransmission would be more common in continuing smokers than among women who quit smoking.  相似文献   
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Segel  MC; Paulus  DD; Hortobagyi  GN 《Radiology》1988,169(1):49-54
The response to induction chemotherapy is an important prognostic factor in patients with nonmetastatic, locally advanced breast carcinomas. Assessment at mammography of the response of 60 breast cancers in 59 women was performed between 1974 and 1986. Responses were excellent in 13 tumors, moderate in 34, and poor in 13 (excellent moderate = 78%). Assessment of response of discrete masses in a fatty breast was easiest; assessment of response of tumor areas that were poorly defined-such as a focal area of architectural distortion or mass in dense breast parenchyma-was more difficult. Of 17 patients with excellent pathologic responses-that is, minimal or no residual tumor-15 (88%) had complete responses (no residual tumor) as determined with mammography, physical examination, or both. Mammography provides information complementary to physical examination and is essential in the accurate assessment of the response to chemotherapy of locally advanced breast cancer.  相似文献   
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Donor insemination (DI) using cryopreserved semen commenced at The Royal Women's Hospital in 1976. Over the next 15 years we performed 5953 treatment cycles to achieve 816 pregnancies (13.7% per cycle) and 706 live births. In-vitro fertilization (IVF) using donor spermatozoa commenced in 1986. Over the next 5 years we performed 303 treatment cycles for 185 couples. Including subsequent transfer of cryopreserved embryos, a total of 33% of couples achieved a successful pregnancy by IVF. Statistical analysis indicated that, for DI pregnancies, the most important semen variable was the percentage post-thaw motility, whilst for normal fertilization in IVF it was the pre-freeze motility. These results may be explained by the compensatory effects of post-thaw processing of spermatozoa for IVF, but not for DI in our clinic.   相似文献   
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OBJECTIVES: Multitransfused adult beta-thalassemic patients constitute a population with high prevalence of hepatitis C virus (HCV) infection, because of transmission of HCV from infected blood donors prior to the introduction of anti-HCV screening. The aim of this study was to compare them with otherwise normal patients with HCV infection. METHODS: Forty-two adult multitransfused beta-thalassemics and 49 otherwise normal patients of the same age, with chronic HCV infection were studied. Viral parameters, autoimmunity indices and liver histology were evaluated. RESULTS: Serum HCV RNA levels were found significantly lower in thalassemic (median: 65,150 international units per milliliter (IU/ml); range: 3 059 380 IU/ml) than in non-thalassemic (NT) patients (median: 580,000 IU/ml; range: 10,956,000 IU/ml; P=0.001). The most prevalent genotype in thalassemic group was genotype 4 (32.4%) while in NT group was genotype 3a (59.2%). Cryoglobulins were detected in 8/42 (19%) thalassemic patients and in 12/49 (24.5%) NTs. Thalassemic patients had significantly lower levels of C3 and C4 components of complement and higher incidence of anti-nuclear antibodies than those without thalassemia. In patients with thalassemia a lower grading score was noted in liver biopsy compared with those without thalassemia (4.41+/-1.98 vs 5.38 +/- 2.09, P=0.038). On the contrary, thalassemic patients were found to have a higher staging score (3.08 +/- 1.51 vs 2.33 +/- 1.34, P=0.024). CONCLUSIONS: Adult beta-thalassemic patients, compared with other patients with HCV infection, present lower necroinflammatory activity and lower viral load but higher staging score. Autoimmune features are marginally different. Age of acquiring the infection, iron overload and modulation of immune system by transfusions are the proposed causes of these differences.  相似文献   
9.

Objective

Patients with chronic obstructive pulmonary disease (COPD) present systemic inflammation. Strenuous resistive breathing induces systemic inflammation in healthy subjects. We hypothesized that the increased respiratory load that characterizes COPD can contribute to systemic inflammation in these patients.

Patients and methods

To test this hypothesis, we compared leukocyte numbers and levels of circulating cytokines (tumor necrosis factor alpha [TNFα], interleukin-1β [IL-1β], IL-6, IL-8, and IL-10), before and 1 hour after maximal incremental inspiratory loading in 13 patients with stable COPD (forced expiratory volume in one second [FEV1] 29 ± 2.5% ref) and in 8 healthy sedentary subjects (FEV1 98 ± 5% ref).

Results

We found that: (1) at baseline, patients with COPD showed higher leukocyte counts and IL-8 levels than controls (p < 0.01); and, (2) one hour after maximal inspiratory loading these values were unchanged, except for IL-10, which increased in controls (p < 0.05) but not in patients with COPD.

Conclusions

This study confirms the presence of systemic inflammation in COPD, shows that maximal inspiratory loading does not increase the levels of pro-inflammatory cytokines (IL-1β, IL-8) in COPD patients or controls, but suggests that the former may be unable to mount an appropriate systemic anti-inflammatory response to exercise.  相似文献   
10.
AIM: Acute gastrointestinal bleeding is a severe complication in patients receiving long-term oral anticoagulant therapy. The purpose of this study was to describe the causes and clinical outcome of these patients. METHODS: From January 1999 to October 2003, 111 patients with acute upper gastrointestinal bleeding (AUGIB) were hospitalized while on oral anticoagulants. The causes and clinical outcome of these patients were compared with those of 604 patients hospitalized during 2000-2001 with AUGIB who were not taking warfarin. RESULTS: The most common cause of bleeding was peptic ulcer in 51 patients (45%) receiving anticoagulants compared to 359/604 (59.4%) patients not receiving warfarin (P<0.05). No identifiable source of bleeding could be found in 33 patients (29.7%) compared to 31/604 (5.1%) patients not receiving anticoagulants (P=0.0001). The majority of patients with concurrent use of non-steroidal anti-inflammatory drugs (NSAIDs) (26/35, 74.3%) had a peptic ulcer as a cause of bleeding while 32/76 (40.8%) patients not taking a great dose of NSAIDs had a negative upper and lower gastrointestinal endoscopy. Endoscopic hemostasis was applied and no complication was reported. Six patients (5.4%) were operated due to continuing or recurrent hemorrhage, compared to 23/604 (3.8%) patients not receiving anticoagulants. Four patients died, the overall mortality was 3.6% in patients with AUGIB due to anticoagulants, which was not different from that in patients not receiving anticoagulant therapy. CONCLUSION: Patients with AUGIB while on long-term anticoagulant therapy had a clinical outcome, which is not different from that of patients not taking anticoagulants. Early endoscopy is important for the management of these patients and endoscopic hemostasis can be safely applied.  相似文献   
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