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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   
2.
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   
3.
4.
Factors that relate to reproductive patterns in 129 families after the birth of a child with phenylketonuria (PKU) include birth order of the index child, age of the parents at the birth of the index child, and expressed intentions of the parents whether or not to have additional children. Factors that do not correlate with reproductive histories include knowledge of the genetic and metabolic nature of PKU, the relationship of PKU to mental retardation and special diet, parental upset about the diagnosis, sex of the affected child, parental IQ, religion, education, and social class. Correlations found related to the question, "Is PKU the reason you don't want more children?" include stress factors in family functioning, mother's upset with the diagnosis, father's concerns about being a carrier, sex of the child with PKU, and degree of knowledge about PKU. Many of the Collaborative Study clinics tend to be more concerned about the consequences of PKU on the family than on society, and feel that families should receive genetic counseling to determine their reproductive risks and future plans. Upon self-report, many clinics declare their counseling to be either "completely nondirective" or making a "conscious effort to be nondirective."  相似文献   
5.
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   
6.
7.

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   
8.

Background

As part of the development of the Neurocritical Care Society (NCS) Status Epilepticus (SE) Guidelines, the NCS SE Writing Committee conducted an international survey of SE experts.

Methods

The survey consisted of three patient vignettes (case 1, an adult; case 2, an adolescent; case 3, a child) and questions regarding treatment. The questions for each case focused on initial and sequential therapy as well as when to use continuous intravenous (cIV) therapy and for what duration. Responses were obtained from 60/120 (50%) of those surveyed.

Results

This survey reveals that there is expert consensus for using intravenous lorazepam for the emergent (first-line) therapy of SE in children and adults. For urgent (second-line) therapy, the most common agents chosen were phenytoin/fosphenytoin, valproate sodium, and levetiracetam; these choices varied by the patient age in the case scenarios. Physicians who care for adult patients chose cIV therapy for RSE, especially midazolam and propofol, rather than a standard AED sooner than those who care for children; and in children, there is a reluctance to choose propofol. Pentobarbital was chosen later in the therapy for all ages.

Conclusion

There is close agreement between the recently published NCS guideline for SE and this survey of experts in the treatment of SE.  相似文献   
9.

Introduction

Propofol is used extensively in neurocritical care (NCC) due to its pharmacologic properties allowing for facilitation of serial neurologic examinations. Despite widespread use, few studies have identified risk factors for hypotension in these patients. We aimed to determine predictors of hypotension in NCC patients sedated with propofol.

Methods

This retrospective, multicenter study evaluated 237 patients at two academic medical centers, both with dedicated NCC teams led by board-certified neurointensivists. Univariate analyses were performed to determine risk factors associated with severe hypotension during sedation with propofol. Multivariable analysis was performed to determine variables independently associated with hypotension, defined as a mean arterial pressure (MAP) less than 60 mmHg.

Results

There was an average maximum reduction in MAP of 28.8 % after propofol initiation in the entire cohort. Severe hypotension developed in 62 (26.2 %) patients to a median nadir MAP of 56 mmHg. Those who developed severe hypotension had a longer median duration of mechanical ventilation (5.0 vs. 3.6 days; p = 0.01) and an increased in-hospital mortality (38.7 vs. 24.0 %; p = 0.03). Multivariable logistic regression analysis identified increasing number of changes to the propofol infusion rate, baseline MAP 60–70 mmHg, and need for renal replacement therapy (RRT) as factors independently associated with hypotension.

Conclusions

Multiple factors predicted hypotension in NCC patients receiving propofol. Clinicians should use propofol cautiously in patients with a lower baseline MAP or receiving RRT. Development of protocols related to the frequency of dose titrations is also recommended to prevent this avoidable complication.  相似文献   
10.
Traumatic brain injury (TBI) is a major cause of death and disability worldwide. In large part critical care for TBI is focused on the identification and management of secondary brain injury. This requires effective neuromonitoring that traditionally has centered on intracranial pressure (ICP). The purpose of this paper is to review the fundamental literature relative to the clinical application of ICP monitoring in TBI critical care and to provide recommendations on how the technique maybe applied to help patient management and enhance outcome. A PubMed search between 1980 and September 2013 identified 2,253 articles; 244 of which were reviewed in detail to prepare this report and the evidentiary tables. Several important concepts emerge from this review. ICP monitoring is safe and is best performed using a parenchymal monitor or ventricular catheter. While the indications for ICP monitoring are well established, there remains great variability in its use. Increased ICP, particularly the pattern of the increase and ICP refractory to treatment is associated with increased mortality. Class I evidence is lacking on how monitoring and management of ICP influences outcome. However, a large body of observational data suggests that ICP management has the potential to influence outcome, particularly when care is targeted and individualized and supplemented with data from other monitors including the clinical examination and imaging.  相似文献   
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