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21.
The erythrocyte alanine aminotransferase (Ala-AT) activity, measured in vitro, of rheumatoid arthritis patients under treatment with penicillamine was markedly stimulated by the addition of excess pyridoxal-5′-phosphate (PLP). This indicates that penicillamine can produce a deficiency of vitamin B6, possibly by reacting chemically with the coenzyme PLP or by inhibiting PLP synthesis. The deficiency, though demonstrable by biochemical tests, was not accompanied by clinical signs of vitamin B6 lack, and it would not justify the administration of a pyridoxine supplement to penicillamine-treated patients except in those of low nutritional status. In addition to its effect on the coenzyme PLP penicillamine also decreased the concentration of the erythrocyte Ala-AT apoenzyme.  相似文献   
22.
OBJECTIVE: The use of bilateral adrenalectomy in the management of congenital adrenal hyperplasia (CAH) is controversial. We set out to review the outcome of 5 cases of CAH who have undergone adrenalectomy in our unit. DESIGN: A retrospective case note review and subject interview of the experience of adrenalectomy in the setting of a tertiary adult CAH clinic. METHODS: Subjects who had undergone adrenalectomy were reviewed at a routine clinic visit with particular reference to clinical and biochemical outcomes after adrenalectomy. RESULTS: Two subjects underwent surgery for the sole indication of desire for fertility with successful outcome and without subsequent adrenal crises. Three women suffered from the common clinical management problem of unsuppressible hyperandrogenism and worsening obesity. Whilst the outcome of improved appearance and weight loss was achieved in these subjects, all three experienced significant complications including pigmentation and acute episodes of adrenal insufficiency. CONCLUSION: We present a mean follow-up of 4.2 patient years and conclude that this procedure may be suitable for selected women with CAH. Outcomes for those pursuing fertility were positive; however, complications were noted in those women for whom the procedure was performed for symptom control. Accepting that the number of subjects is small, it is clear that more data are required before widely recommending this procedure.  相似文献   
23.
M Rumsby  F Suggitt  L Haynes  E Hughson  D Kidd  S McNulty 《Glia》1999,26(4):361-367
Pleiotrophin (HB-GAM), an extracellular matrix-associated protein with a high content of basic amino acid residues, is expressed in the central nervous system during late pre- and early post-natal development and promotes neurite outgrowth in vitro. Here, we show that, on a substratum of pleiotrophin formed from a 5 or 10 microg/ml solution, undifferentiated rat CG-4 line oligodendrocytes adopt a bipolar morphology and disperse over the substratum, as we have previously shown with poly-L-lysine (Rumsby et al. Neurosci. Res. Commun. 23:101-109, 1998). On pleiotrophin substrata formed from coating solutions of 1 microg/ml and below, CG-4 line cells form aggregates and do not disperse, as is also the case with poly-L-lysine. The same dispersing effect is observed with rat primary 0-2A progenitor glial cells on pleiotrophin substrata from solutions of 5 and 10 microg/ml: 0-2A cells aggregate together on pleiotrophin substrata formed from lower concentrations and do not disperse. A pleiotrophin substratum enhances proliferation of CG-4 line oligodendrocytes and primary 0-2A progenitor glial cells. The results show that pleiotrophin provides a substratum that can influence progenitor oligodendrocyte morphology, aid cell dispersion, and perhaps also enhance progenitor oligodendrocyte cell growth.  相似文献   
24.
25.
The effects of three ultraviolet excimer laser wavelengths on normal and atheromatous human cadaver aortic wall are presented. Ultraviolet radiation successfully ablates vessel wall; the dose response is greatest at 249 nm followed by 193 nm and 351 nm, where the effect is negligible for the equivalent energy dose. Wavelengths 249 and 193 nm have a selective effect on fibrous atheroma; ablation proceeds at a higher rate in this tissue. Non-linear effects observed at 249 nm may be due to thermal as well as photoablative mechanisms. In addition, blood samples were exposed to all three wavelengths and potassium concentrations were measured; the dose of energy required to produce tissue ablation may also produce significant haemolysis and hyperkalaemia at 249 and 193 nm but not with 351 nm. This finding may be important for coronary angioplasty but less so for peripheral work. The wavelength that produces the strongest dose response is 249 nm; this is the wavelength for which a fibre-optic delivery system should be developed.  相似文献   
26.
OBJECTIVE  Dysregulation of 17α-hydroxylase (CYP17) has been proposed as a cause of hyperandrogenism. We have determined the prevalence of a polymorphic allele in the CYP17 gene in sporadic patients with polycystic ovaries (PCOS) compared to a reference population, and to a group of hyperandrogenic individuals, to assess its significance to androgen production.
PATIENTS AND DESIGN  DNA was isolated from EDTA blood samples from 69 patients with PCOS, 63 patients with congenital adrenal hyperplasia secondary to 21-hydroxylase deficiency and 124 consecutive patients attending for a full blood examination. The thymine (T) to cytosine (C) polymorphism at −34 base pairs (bp), denoted alleles A1 and A2 respectively, was detected by amplification of DNA followed by restriction enzyme digestion.
MEASUREMENTS  Testosterone and LH. The frequency of alleles A1 and A2 in each of the subject groups was determined.
RESULTS  The prevalences of the A1 and A2 alleles were 75 and 25% respectively in the PCOS group which was not significantly different from that in either the hyperandrogenic or the reference group. Neither allele segregated with hyperandrogenism.
CONCLUSION  The polymorphism plays no apparent role in the dysregulation of CYP17.  相似文献   
27.
Glial cell primary cultures consisting of protoplasmic and fibrous astrocytes, oligodendrocytes and progenitor glial cells incubated in medium containing 0.5% foetal calf serum and treated with 25 nM 12-o-tetradecanoylphorbol-13-acetate (TPA) for periods between 15 and 60 min showed a stimulation of protein phosphorylation which was most prominent in a polypeptide with a molecular weight of about 80,000 Da. Glial subcultures consisting mainly of Type 2 astrocytes, oligodendrocytes and progenitor glia showed a similar TPA stimulation of 80,000 Da protein phosphorylation detectable within 1 min of phorbol ester addition. TPA treatment of primary glial cultures led to an enhancement of phospholipid turnover but exposure of primary glial cultures to concentrations of TPA up to 250 nM caused no morphological change in protoplasmic astrocytes. 4-Phorbol (4-PH) or dimethylsulfoxide (DMSO) was without effect on protein phosphorylation or lipid turnover in glial cultures.  相似文献   
28.
We report a child in whom DOC excess secondary to congenital adrenal hyperplasia (CAH, 11β-hydroxylase deficiency) caused malignant hypertension. Clinical and metabolic control could be achieved only by replacement of both glucocorticoid and mineralocorticoid, thus confirming in clinical practice the hypothesis that DOC is produced from both the zonae fasciculata and glomeru-losa of the adrenal cortex under the independent control of the ACTH and renin-angiotensin systems respectively.  相似文献   
29.

Background

In most developed countries, the prevalence of smoking remains stubbornly high in lower socioeconomic groups. Male manual workers in England are more than twice as likely as those in managerial and professional occupations to smoke (26% vs 11%), find it more difficult to quit, and have the highest relapse rates. We sought to determine perceived factors in smoking cessation and relapse in this hard-to-reach group to inform the development of effective stop smoking services and public health efforts to reduce the health inequality caused by smoking.

Methods

In this qualitative study in southeast England, 12 male manual workers (aged 18–65 years), who had accessed the Sussex Community NHS Trust Stop Smoking Service during the previous 12 months, were recruited into two focus groups (FG 1, n=4; FG 2, n=8). The focus group discussions were guided by structured and prompt questions. The Brighton East Research Ethics Committee approved the study, and written informed consent was obtained from all participants.

Findings

Participants identified three broad themes that influenced their smoking cessation efforts and relapse. First, personal and behavioural factors included effect of smoking on current physical fitness as a stronger motivating factor to quit than long-term health risks, risk of relapse associated with use of recreational substances (drugs, alcohol), positive impact of changing one's daily routine or habits to control smoking triggers, negative impact on children, negative social impact of “smelling of cigarettes”, and perception that women have more willpower and find it easier to quit smoking. Second, environmental factors included triggering effect of stressful life events, increased risk of relapse because of the availability of packs of ten cigarettes, and the beneficial effect of a ban on point-of-sale display and smoking in pubs and bars. Third, social factors included positive impact of support from friends, family, or the local community, and negative impact of perceived greater “social acceptability” of smoking in men and “social acceptability” of smoking versus other addictions (eg, recreational drugs, heroin, alcoholism).

Interpretation

This new insight informs the development of public health interventions, which need to address these social norms and attitudes in this group of disadvantaged smokers. Carefully targeted and effective campaigns with appropriate content and tone may reduce the health inequality caused by smoking.

Funding

Brighton and Sussex Medical School.  相似文献   
30.
Treatment of achondroplasia with growth hormone: six years of experience.   总被引:1,自引:0,他引:1  
We describe the effects of recombinant hGH (r-hGH) therapy for up to 6 y on stature and body proportions of 35 children with achondroplasia (Ach). Consecutive height (Ht) measurements were plotted on disease-specific Ach growth curves, but age and sex SD scores (SDS) of Ht, sitting Ht, subischial leg length, and Ht velocity were made with respect to Tanner normal standards. r-hGH was administered by daily subcutaneous injections at a median (range) dose of 30 (15.8-40) U/m2 per week [0.06 (0.04-0.08) mg.kg(-1).24 h(-1)]. Patients were treated for 3 (1-6) y from age 2.25 (1.2-9.3) y. Before treatment, Ht SDS was -4.6 (-6.5 to -3.24). Treatment caused a significant increase in Ht SDS year to year until y 4 (ANOVA F = 46.94; p < 0.01) that was subsequently sustained with no significant further change (y 5 and 6 versus y 4, p > 0.05). When the response to r-hGH was also expressed as a change in Ht velocity, there was a significant increase in the first year of therapy that was maintained over subsequent treatment years (ANOVA = 4.28, p = 0.001). Age was the most important variable accounting for the first-year response in Ht SDS (r2 = 0.41, p < 0.001), and dose of r-hGH did not influence this. Increments in sitting Ht SDS were greater than subischial leg length SDS (F = 26.25, p < 0.001; F = 9.04, p < 0.001, respectively). r-hGH treatment improved the Ht position of Ach children relative to their normal and Ach peers without obvious side effects. A young age at initiation of therapy prevented the characteristic Ht deficit from accumulating. The greater increase in spinal Ht accentuated the existing disproportion. The addition of later surgical leg lengthening could offer the possibility of proportionate adult stature just within the normal range.  相似文献   
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