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1.
Recent studies with standardized laboratory measurements of skin blood flow suggest an influence of female sex hormones on vasospasm. Therefore we evaluated the influence of sex hormonal status on the subjective complaints of Raynaud's phenomenon and furthermore the combined presence of Raynaud's phenomenon and migraine. A detailed questionnaire was filled in by 130 primary Raynaud patients (31 males, 99 females), while 27 females, with regular menstrual cycles without the use of oral contraceptives, kept a diary with daily registration (during three months) of frequency, severity and duration of the vasospastic attacks. Complaints improved during pregnancy in 6 out of 23 females. No influence of the menopause or the use of oral contraceptives was found. An exacerbation in some phases of the menstrual cycle was present in 15 out of 80 females. The diaries, however, did not show such influence of menstrual cycle phase. Migraine was present in 21% of the Raynaud patients. In contrast to most reports in the literature and contrary to the results of laboratory research, this study shows that most females do not experience an important subjective influence of sex hormonal status on vasospastic attacks.  相似文献   
2.
BACKGROUND: In patients with intermittent claudication, exercise in the form of walking is effective in reducing pain and maximising achievable walking distance. However, data are lacking on the implementation of walking exercise in these patients. AIMS: To explore the current behaviour and views of patients with intermittent claudication towards taking walking exercise. DESIGN OF STUDY: Postal questionnaire and focus group meetings. SETTING: Two academic general practice networks (Utrecht and Maastricht Universities) in The Netherlands. METHOD: Three hundred and seventy-five patients with intermittent claudication, selected from the files of general practitioners participating in two academic general practice networks, were sent a postal questionnaire; 216 (58%) were returned. Nine of these responders also attended a focus group meeting. RESULTS: Seventy per cent (151/216) of the patients reported having received advice about walking exercise. If specified, the advice given most often recommended walking in the local neighbourhood (56%, 84/151). Fifty-two per cent (113/216) of all patients actually performed walking exercise and only 32%of them received any kind of supervision. Among the barriers for taking walking exercise, 'comorbidity', 'lack of (specific) advice' and 'lack of supervision' were often mentioned. Among the stimuli to start and continue walking, 'following the doctor's advice', 'relief of complaints' and 'a better general condition' were often mentioned by patients. CONCLUSIONS: Walking exercise was not carried out by almost half of patients with intermittent claudication in this study. Lack of specific advice and supervision were found to be important barriers to taking walking exercise.  相似文献   
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BACKGROUND AND PURPOSE: The optimal intensity fluence profile of a beam depends on the profiles of other beams but most optimizations assume fixed beam orientations, a priori. Breast cancer radiotherapy attempts to cover the target and to spare critical structures such as the heart and lungs. The study aims are (1) to determine and document the optimal two-beam orientation that best spares the heart for left-sided breast cancer patients and (2) to investigate the influence of the treatment technique (i.e., conformal versus intensity modulation) on the optimal objective cost function. MATERIAL AND METHODS: Ten left-sided breast cancer patients were planned using a conformal (3DCRT) and a simplified intensity modulated (sIMRT) technique using predefined segments and different two-beam orientations. Optimal segment weights were determined exhaustively for all axial two-beam combinations, in 5 degree increments, by minimizing a quadratic objective cost function. The resulting objective cost function was analyzed with respect to target geometry and treatment technique. RESULTS: The sIMRT plans are generally less sensitive to beam orientation compared to 3DCRT plans. Optimal two-beam orientations for 3DCRT and sIMRT plans exist and they correspond to a hinge angle of approximately 188 degrees and 160 degrees or 210 degrees (the latter is bimodal), respectively. CONCLUSIONS: The optimization software is a useful tool that can test many different beam combinations and estimate their associated objective cost values. Afterwards, the most promising beam orientations could be re-optimized under the TPS to fine-tune and verify the dose distributions. Optimal uniform two-beam orientations for the breast consist of opposing tangential medial and lateral beams. Optimal nonuniform two-beam orientations for left-sided breast cancers are bimodal, containing hinge angles around 160 degrees and 210 degrees. Nonuniform beam techniques are less sensitive to beam orientation compared to uniform beam techniques and result in significantly improved heart sparing but at a cost of slightly compromised planning target volume coverage.  相似文献   
5.
BACKGROUND: Patients with hypertension and renal-artery stenosis are often treated with percutaneous transluminal renal angioplasty. However, the long-term effects of this procedure on blood pressure are not well understood. METHODS: We randomly assigned 106 patients with hypertension who had atherosclerotic renal-artery stenosis (defined as a decrease in luminal diameter of 50 percent or more) and a serum creatinine concentration of 2.3 mg per deciliter (200 micromol per liter) or less to undergo percutaneous transluminal renal angioplasty or to receive drug therapy. To be included, patients also had to have a diastolic blood pressure of 95 mm Hg or higher despite treatment with two antihypertensive drugs or an increase of at least 0.2 mg per deciliter (20 micromol per liter) in the serum creatinine concentration during treatment with an angiotensin-converting-enzyme inhibitor. Blood pressure, doses of antihypertensive drugs, and renal function were assessed at 3 and 12 months, and patency of the renal artery was assessed at 12 months. RESULTS: At base line, the mean (+/-SD) systolic and diastolic blood pressures were 179+/-25 and 104+/-10 mm Hg, respectively, in the angioplasty group and 180+/-23 and 103+/-8 mm Hg, respectively, in the drug-therapy group. At three months, the blood pressures were similar in the two groups (169+/-28 and 99+/-12 mm Hg, respectively, in the 56 patients in the angioplasty group and 176+/-31 and 101+/-14 mm Hg, respectively, in the 50 patients in the drug-therapy group; P=0.25 for the comparison of systolic pressure and P=0.36 for the comparison of diastolic pressure between the two groups); at the time, patients in the angioplasty group were taking 2.1+/-1.3 defined daily doses of medication and those in the drug-therapy group were taking 3.2+/-1.5 daily doses (P<0.001). In the drug-therapy group, 22 patients underwent balloon angioplasty after three months because of persistent hypertension despite treatment with three or more drugs or because of a deterioration in renal function. According to intention-to-treat analysis, at 12 months, there were no significant differences between the angioplasty and drug-therapy groups in systolic and diastolic blood pressures, daily drug doses, or renal function. CONCLUSIONS: In the treatment of patients with hypertension and renal-artery stenosis, angioplasty has little advantage over antihypertensive-drug therapy.  相似文献   
6.
The hypo-osmotic swelling test (HOST or HOS test) usually takes into consideration the total HOS response value with no emphasis either on the value of the response subtypes or the response evaluation time. This study investigated the time course of HOS responses and analysed their physiological relevance. Raw semen spermatozoa and Percoll washed spermatozoa were used in the experiment. The morphological changes in the sperm tail were monitored by incubating the spermatozoa in the hypo- osmotic solution for 16 different time periods. The HOS reactive spermatozoa and the type of HOS reaction (swelling subtypes) of the samples subjected to different duration of treatment were identified under a phase contrast microscope. Also the fate of individual spermatozoa in a hypo-osmotic environment were monitored for 30 min. In spermatozoa exposed to a hypo-osmotic solution, the motility lasted usually less than 2 min and motility characteristics were uniquely different from that of the spermatozoa under iso-osmotic conditions. The HOS response development was permanent but the motility loss due to hypo-osmotic shock was reversible up to 1 min of incubation. There was an indication of ordered transition among the HOS swelling subtypes apparently initiating with subtype b destined to c, d, e, f and g. Further, the subtypes a and g showed gradual decrease and increase, respectively, while subtype b showed abrupt initial increase and then gradual decrease. Transition from b to g could be direct or via one or more than one subtypes. Ultrastructure based analysis indicated that HOS response subtypes are the apparent reflection of the differences in the cytoskeletal assembly of the sperm tail and thus may be identifying different physiological variants in the sperm population. These results indicate that shorter incubation is essential to document the kinetics of various HOS responses but the conventional HOS test misses these important HOS features because of lengthy incubation. Since the time course of ordered transition of HOS responses will vary more than the total HOS response in semen of different aetiologies, the importance of HOS response subtypes and response evaluation time should be taken into consideration when applying HOS test.   相似文献   
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BACKGROUND: If a validated questionnaire, when applied to patients reporting with symptoms of intermittent claudication, could adequately discriminate between those with and without peripheral arterial disease, GPs could avoid the diagnostic measurement of the ankle brachial index. AIM: To investigate the Edinburgh Claudication Questionnaire (ECQ) in general practice and to develop a clinical decision rule based on risk factors to enable GPs to easily assess the likelihood of peripheral arterial disease. DESIGN OF STUDY: An observational study. SETTING: General practice in The Netherlands. METHOD: This observational study included patients of > or =55 years visiting their GP for symptoms suggestive of intermittent claudication or with one risk factor. The ECQ and the ankle brachial index were performed. The prevalence of peripheral arterial disease, defined as an ankle brachial index <0.9, was related to risk factors using logistic regression analyses, on which a clinical decision rule was developed and related to the presence of peripheral arterial disease. RESULTS: Of the 4790 included patients visiting their GP with symptoms suggestive of intermittent claudication, 4527 were eligible for analyses. The prevalence of peripheral arterial disease in this group was 48.3%. The sensitivity of the ECQ was only 56.2%. The prevalence of peripheral arterial disease in a clinical decision rule that included age, male sex, smoking, hypertension, hypercholesterolemia, and a positive ECQ, increased from 14% in the lowest to 76% in the highest category. CONCLUSION: This study indicates that the ECQ alone has an inadequate diagnostic value in detecting patients with peripheral arterial disease. The ankle brachial index should be performed to diagnose peripheral arterial disease in patients with complaints suggestive of intermittent claudication, although our clinical decision rule could help to differentiate between extremely high and lower prevalence of peripheral arterial disease.  相似文献   
9.
The value of cell kinetic measurements in head and neck tumors in predicting which patients will benefit from accelerated fractionation radiotherapy regimens is being tested in a multicenter European trial (EORTC trial 22851). This paper reports on the first analysis of the correlation of kinetics with outcome in this trial. A proportion of patients in both the accelerated arm (72 Gy in 5 weeks, 1.6Gy per fraction, 45 fractions) and the conventional arm (70-72 Gy in 7-8 weeks, 1.8-2.0 Gy per fraction, 35-40 fractions) were given an i.v. injection of 100 mg/m2 IUdR (iododeoxyuridine) before treatment, and a tumor biopsy was taken several hours later. The potential doubling time of the tumor (Tpot) was obtained from a flow cytometric analysis of tumor cell nuclei using an anti-IUdR antibody. From a total of 260 patients entered in the trial, 53 have undergone kinetic analysis. Adequate IUdR labeling was seen in 47 patients (88.7%), from which the mean value for Tpot was found to be 4.5 +/- 2.5 days (+/- S.D.). Of the IUdR labeled patients, 30 have now been followed up for at least 1 year, 17 with conventional and 13 with accelerated radiotherapy. These patients were split into those with fast and those with slowly growing tumors, the dividing line being the median Tpot value of 4.6 days. After conventional 7-week radiotherapy, 2 of 6 patients with "fast" growing tumors obtained local control compared with 8 of 11 with "slow" growing tumors. A small difference in local control was seen been fast and slow tumors in the accelerated arm (5/9 vs. 3/4). These preliminary data support the hypothesis that patients with fast growing tumors do poorly with conventional radiotherapy and that pretreatment kinetic measurements can select patients at risk. The predictive power of the method must await the final analysis of trial results.  相似文献   
10.
The effects of sex, the menstrual cycle, oral contraceptives, pregnancy, and the menopause on skin perfusion in healthy women and in patients with Raynaud's phenomenon suggest a role of female sex hormones. However, no clear relation between skin blood flow and circulating concentrations of oestrogens or progestogens has yet been found. The aim of this study was to investigate the effect of orally administered 17-oestradiol and progesterone on finger skin blood flow before and during heat and cold challenge in 17 healthy normotensive women and in 12 women with Raynaud's phenomenon.In each subject standardized finger heating (45°;C water bath, 10 min) and cooling tests (15°;C water bath, 5 min and 20 min recovery) were performed twice on the second (or third) day of two consecutive menstrual cycles. 17-Oestradiol (9 mg) or progesterone (300 mg) were given before the second test, after a first test with placebo. Both hormonal doses resulted in (high) physiological concentrations. Fingertip skin temperature and laser Doppler flux were measured.There were no significant differences in the test results after placebo and after progesterone. Although values of fingertip skin temperature and laser Doppler flux after 17-oestradiol tended to be higher only the precooling values in the healthy subjects reached significance: fingertip skin temperature respectively with placebo and with oestradiol (mean (SD)): 32.7 (1.0) and 33.1 (0.8)°;C; laser Doppler flux with placebo and with oestradiol: 33.6 (11.7) and 42.2 (9.5) perfusion units; both P<0.05). In this study, single oral doses of female sex hormones had only minor effects on finger skin circulation, both in control subjects and in women with Raynaud's phenomenon.  相似文献   
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