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81.
CATRINA HEFFERNAN BSc  MSc  PGDE  RNT  RGN    ELIZABETH HEFFERNAN BSc  MA  HDip  HDip  RNT  RM  RGN    MARY BROSNAN MComm  BNS  RNT  RGN  RNID    GARY BROWN MSc  PhD  RNT  RGN 《Journal of nursing management》2009,17(5):539-549
Aim  The study sought to evaluate stakeholder perspective of preceptor preparation and attributes.
Background  In Ireland, undergraduate students are supported by a named preceptor on clinical placement. A preceptor is a registered nurse who has completed a teaching, assessment and preceptorship programme. Preceptor preparation is costly in terms of facilitation and staff release/replacement. To date, in Ireland, research has not explored the effectiveness of preceptor preparation.
Method  An utilization-focussed approach was adopted incorporating a two-phase research process; Phase 1 being exploratory while Phase 2 aimed to validate inductions derived from the previous stage.
Results  The programme is effective in meeting its learning outcomes. The findings are categorized into four theme areas: the importance of preceptor characteristics, the demonstration of these characteristics, knowledge demonstrated by the preceptors and the skills demonstrated by the preceptor.
Conclusion(s)  Preceptors, to be effective within the preceptor/student relationship, need to integrate both their professional and personal attributes to effectively socialize students to the profession of nursing.
Implications for nursing management  The preceptor role is invaluable within nurse education. This study supports the release of registered nurses to attend preceptor preparation programmes. It highlights the importance of nursing management in preceptor selection, release, support and monitoring in order to create an effective clinical learning environment.  相似文献   
82.
BACKGROUND Seborrheic keratoses (SKs) are benign cutaneous tumors of the epidermis. Localization in the head and neck areas can produce an unsightly appearance. Recurrence after curettage, shave excision, cryoablation, or chemical peel can be common.
OBJECTIVE The objective was to determine if laser ablation with the 532-nm laser and color enhancement is effective in removing SKs.
MATERIALS AND METHODS A total of 326 patients who presented with 1,567 benign SKs were treated with the DioLite (Iridex Corp.) and VersaPulse cosmetic (Coherent Inc.) 532-nm diode lasers with color enhancement using a red marker or ferric subsulfate. The DioLite was set at 27 to 30 J with a 2- to 3-mm spot size, and a 10-ms pulse width was used for ablation. The VersaPulse was set at a lower energy of 9.5 to 12 J/cm2 with a 3-mm spot size, 3- to 6-Hz repetition rate, and 10-ms pulse duration for ablation. All patients were Caucasian.
RESULTS Complete resolution of the SKs occurred in 93% of lesions. Seven percent of SKs required a second round of laser treatment for incomplete ablation. There were no cases of hyperpigmentation or hypertrophic scar formation of the skin following laser treatment. Hypopigmentation occurred in 6% of patients and was associated with old, chronic, or recalcitrant lesions.  相似文献   
83.
Surgical revascularization for severe atherosclerotic stenoses of the infrarenal abdominal aorta is associated with increased morbidity and mortality. We present our experience with percutaneous stenting as a less invasive treatment alternative in seven consecutive patients with the disease (six females, mean age: 63 ± 5). Technical success was achieved in all patients with reduction of the mean percent stenosis from 85 ± 3% down to 13 ± 2%. A total of seven stents were used; 5 Wallstents and 2 Palmaz stents. No immediate complications were observed. One patient developed left leg ischemia due to worsening of a preexisting left iliac lesion a day after the procedure and was successfully stented. All patients were asymptomatic at follow-up (mean: 27 ± 3 months). The mean ABI was 0.91 ± 0.12 and 0.94 ± 0.15 on the right and left sides, respectively. These results suggest that stenting of focal infrarenal abdominal stenoses is effective and associated with favorable late outcome  相似文献   
84.
85.

Purpose

At our institution the Kock ileal neobladder has been the primary form of urinary diversion after cystectomy. The few associated complications are primarily related to the intussuscepted antireflux afferent limb, including stones, stenosis and extussusception of the afferent nipple. We present a novel orthotopic ileal neobladder, the T pouch, with an innovative antireflux technique designed to prevent complications of the intussuscepted afferent nipple.

Material and Methods

From November 1996 through August 1997, 40 patients an average of 67 years old underwent construction of an orthotopic ileal neobladder (T pouch). Mean followup is 10.5 months (range 8 to 14). The T pouch incorporates an antireflux mechanism using a serosal lined ileal tunnel technique. Urinary reflux is prevented without ileal intussusception and with complete preservation of the blood supply to the afferent ileal segment. Followup in all cases includes clinical and functional results, and radiographic evaluation of the urinary reservoir and upper urinary tracts.

Results

One perioperative death (2.5%) and 5 early complications (12.5%) were unrelated to urinary diversion. There have been no late complications. All T pouch reservoirs had excellent capacity without evidence of urinary reflux. The upper urinary tracts remain unchanged or improved in all patients.

Conclusions

The T pouch is an orthotopic ileal neobladder that incorporates an effective, innovative antireflux mechanism created by a serosal lined ileal tunnel. Early clinical and functional results of this type of urinary diversion have been excellent. Furthermore, we suspect that this antireflux technique may eliminate the complications associated with an intussuscepted afferent nipple and maintain an effective antireflux mechanism.  相似文献   
86.
VARIATIONS IN VALSALVA LEAK POINT PRESSURE WITH INCREASING VESICAL VOLUME   总被引:2,自引:0,他引:2  

Purpose

Although leak point pressure testing is a valuable tool in the diagnosis of female stress urinary incontinence, little standardization in methodology exists. We examined the effect of vesical volume on leak point pressure to assess the need for determining an optimal volume for leak point pressure testing.

Materials and Methods

Video urodynamic testing was performed in 52 consecutive women with a mean age of 52 years who presented with stress urinary incontinence. By fluoroscopic criteria stress urinary incontinence was type I in 12 patients, type II in 20 and type III in 20. Leak point pressure determined at 50 cc volume increments was correlated with fluoroscopic criteria.

Results

Women with type I stress urinary incontinence had high leak point pressure, which remained high at increasing vesical volumes, and those with type III had low leak point pressure, which remained low at increasing volumes. In patients with type II incontinence initially high leak point pressure decreased significantly at increasing vesical volumes. The most appropriate classification of patients occurred at a volume of 250 to 300 cc.

Conclusions

Leak point pressure is affected by vesical volume. At a volume of 250 to 300 cc leak point pressure correlates best with fluoroscopic findings, and it may be used to guide therapy in women presenting with stress urinary incontinence.  相似文献   
87.
Evaluation of Changes in the Secretion of Immunoactive Inhibinby Adult Rat Seminiferous Tubules in Vitro as an Indicator ofEarly Toxicant Action on Spermatogenesis. Allenby, G., Foster,P. M. D., and Sharpe, R. M. (1991). Fundam. Appl. Toxicol 16,710–724. A method for culturing isolated seminiferoustubules (ST) from adult rats for 1–3 days has been developedand optimized rigorously on the basis of the secretion of immunoactiveinhibin under basal conditions and after maximal stimulationwith rat FSH or dibutyryl cyclic AMP. The effect on these culturesof three known testicular toxicants was assessed. Of these,two are thought to act on the Sertoli cell, meta-dinitrobenzene(mDNB) and nitrobenzene (NB), while the third, methoxy aceticacid (MAA), is thought to act on pachytene spermatocytes. Inaddition, the effect of a possible testicular toxicant, 3-mononitrotoluene(3-MNT), was investigated. These data were compared with thoseobtained using cultures of immature rat Sertoli cells (SC) orSC + germ cells and with data on the effect of equivalent dosesof the compounds on the secretion of immunoactive inhibin invivo. In studies designed to optimize conditions for the secretionof immunoactive inhibin by ST in culture, significant effectswere found of the type of culture medium used, the durationof culture, the total and individual length of tubules used,etc. All subsequent studies with toxicants utilized optimalconditions. Addition of either mDNB or NB to ST cultures at10–5 or 10–3 m, or MAA at 10–4 m, stimulatedbasal secretion of immunoactive inhibin by two- to fourfoldon Days 1, 2, or 3 of culture while FSH or dibutyryl cyclicAMP-stimulated secretion of immunoactive inhibin was eitherunaffected or was enhanced to a small extent. At the same doses,mDNB or NB also enhanced secretion of immunoactive inhibin bySC cultures, although these effects were more variable and ofsmaller magnitude than the effects on ST cultures. In contrast,addition of up to 10–3 m MAA to cocultures of SC + germcells had no effect on the secretion of immunoactive inhibin.Exposure of rats in vivo to levels of mDNB, NB, or MAA similarto those which stimulated secretion of immunoactive inhibinin vitro resulted in a two-to fourfold increase in the levelsof immunoactive inhibin in testicular interstitial fluid (IF)at 1 and 3 days post-treatment, and this was associated withearly impairment of spermatogenesis (as judged by testis weight).In contrast to these effects, addition of 3-MNT to ST or SCcultures had no effect except at 10–3 m, when the secretionof immunoactive inhibin was increased marginally. Treatmentof rats with an equivalent dose of 3-MNT in vivo resulted indeath, but exposure to the highest nonlethal dose (1 g/kg) hadno significant effect either on spermatogenesis or on the levelsof immunoactive inhibin in testicular IF. In view of these findings,it is concluded that modulation of the secretion of immunoactiveinhibin by isolated ST from adult rats has considerable potentialas an in vitro screening method for investigating potentialadverse effects of chemicals on spermatogenesis, and thus meritsmore detailed evaluation. Moreover, because of the agreementbetween in vitro and in vivo findings, measurement of the levelsof immunoactive inhibin levels in vivo in testicular IF (orblood) may also be useful in the detection of early adverseeffects of chemicals on spermatogenesis.  相似文献   
88.
PROBLEM: To evaluate the independent ability of midtrimester amniotic fluid tumor necrosis factor-alpha (TNF-α) in the prediction of small-for-gestational-age (SGA) infants. METHOD OF STUDY: In this case-control study, patients delivering a SGA infant were matched with controls based on GA at delivery, maternal age, race, and parity. Patients with immune disease, chronic hypertension, diabetes, asthma, congenital hearts disease, multiple gestation, and fetal anomalies were excluded. Amniotic fluid samples were immunoassayed for TNF-α. Potential confounding variables evaluated were maternal serum alpha-fetoprotein level, smoking history, pregnancy induced hypertension, and neonatal gender. Statistical analysis included Fisher's exact test and ANOVA after log transformation with P < 0.05 considered significant. RESULTS: Eighteen patients delivered SGA neonates and were matched with 41 controls. No significant differences were identified in the confounding variables between patients with SGA neonates and controls. Amniotic fluid TNF-α levels were not significantly different between patients subsequently delivering SGA neonates and controls [median 7.63 (range 0.25-16.1) pg/mL versus 9.39 (0.25–66.9) pg/mL, P = 0.8]. CONCLUSIONS: Midtrimester amniotic fluid TNF-α levels are not predictive of SGA neonates when compared with controls matched for gestational age at delivery.  相似文献   
89.
Behavioral contexts can evoke a variety of autonomic modes of response, characterized by reciprocal, coactive, or independent changes in the autonomic divisions. In the present study, we investigated the reactive autonomic control of the heart in response to psychological stressors, using quantitative methods for analyzing single and double autonomic blockades, and through the use of noninvasive indices based on heart period variability and systolic time intervals. Analysis of the effects of pharmacological blockades revealed an overall pattern of increased sympathetic and decreased parasympathetic control of the heart during speech stress, mental arithmetic, and a reaction-time task. Unlike the classical reciprocal sympathetic-parasympathetic response to orthostatic challenge, however, the responses of the autonomic branches to stress were uncorrelated. This reflected notable individual differences in the mode of autonomic response to stress, which had considerable stability across stress tasks. The putative noninvasive indices of sympathetic (preejection period) and parasympathetic (respiratory sinus arrhythmia) control changed in accord with the results of pharmacological blockades. Together, these results emphasize the substantial individual differences in the mode of autonomic response to stress, the advantages of a quantitative approach to analyzing blockade data, and the importance of validity estimates of blockade data.  相似文献   
90.
PROBLEM: Identifying the endometrial antigens inciting autoimmunity is important in setting up an antibody assay for a non-invasive diagnosis and clinical monitoring of endometriosis. METHODS: Two-dimensional gel electrophoresis of endometrial extracts, Western blot analysis, passive hemagglutination and enzyme-linked immunosorbent assay (ELISA), amino acid sequencing and molecular studies were done on chosen antigens. Forty-six women with endometriosis, 4 women with uterine leiomyomata, 4 with pelvic adhesions, 3 with repeat Cesarean sections (conditions that coexist with or predispose to endometriosis) and 46 controls participated. RESULTS: Antigens with molecular weights (MW) of 64 kDa [isoelectric point (pI) of 3.5-4.0] and 72 kDa (pI of 4.5) bound to IgG in all patients with endometriosis, but not the controls. Amino acid sequencing of the proteins revealed that they had homology to alpha 2-Heremans Schmidt (HS) glycoprotein (MW: 64 kDa) and transferrin (MW: 72 kDa). Endometriosis patients had significant antibody levels to these two proteins (predictive value of 80–90%). The analysis of patients' endometrial RNA detected the message for alpha 2-HS glycoprotein and transferrin. Albumin (pI 5.5) and collagen (pI 3.5) failed to elicit antibody responses. CONCLUSIONS: Patients with endometriosis have significant antibodies to endometrial transferrin and alpha 2-HS-glycoprotein. We can effectively use an antibody assay using these antigens for diagnosing endometriosis.  相似文献   
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