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71.
Effect of carbon dioxide pneumoperitoneum on bacteremia and severity of peritonitis in an experimental model 总被引:3,自引:3,他引:0
Background: Laparoscopy is increasingly used in conditions complicated by peritonitis. A theoretical concern is that carbon dioxide pneumoperitoneum
may increase bacteremia.
Method: In 60 rats peritonitis was induced by cecostomy. Animals were randomly allocated to pneumoperitoneum (PP) and control groups.
Blood cultures and intraabdominal swabs were assessed. A peritonitis severity score (PSS) was computed based on histology
from peritoneal biopsy.
Results: One hour after cecostomy neither in abdominal swabs nor in blood samples bacteria were reproduced in PP and control groups.
Three hours after cecostomy the frequency of positive blood cultures was 80% and 20% in PP and control groups, respectively
(p < 0.0001). Six hours after cecostomy the frequency of positive blood cultures was 100% in each group (p > 0.05). One hour after cecostomy the mean peritoneal severity score was significantly higher in the PP group than in the
control group, but there was not any significant difference between groups 3 and 6 h after cecostomy. The mean peritoneal
severity scores were found to be significantly increased with time when the PP groups compared with each other.
Conclusion: In rats, pneumoperitoneum can't cause a more severe peritonitis but it does induce an increase in the rate of bacteremia
within the early 6-h period of peritonitis.
Received: 14 April 1997/Received: 18 September 1997 相似文献
72.
73.
Yilmaz O Genc A Taneli F Demireli P Deveci Kocakoc I Sencan A Gunsar C Mir E Taneli C 《Scandinavian journal of urology and nephrology》2006,40(1):12-16
OBJECTIVE: To investigate long-term testicular function in pentoxifylline- and NG-nitro-L-arginine methyl ester (L-NAME)-treated rats prior to spermatic artery ligation by assessing serum inhibin B concentration, a reliable endocrine marker of spermatogenesis. MATERIAL AND METHODS: Forty prepubertal rats were randomly divided into four equal groups. Right orchiectomy was performed in all rats. Intraperitoneal pentoxifylline and L-NAME were administered to Groups 1 and 2, respectively. Rats in Group 3 did not receive any medication. The spermatic arteries of the left testes were ligated in all groups with the exception of the sham controls (Group 4). One month postoperatively, a histopathologic evaluation was performed and serum inhibin B concentrations were assessed in all groups. RESULTS: There were no statistically significant differences in testis size or serum inhibin B concentration between Groups 1, 2 and 3. However, the testes were significantly smaller (p(1)=0.01, p(2)=0.01, p(3)=0.01) and serum inhibin B levels were significantly decreased (p(1)=0.01, p(2)=0.01, p(3)=0.01) when Groups 1-3 were compared with Group 4. Histopathological evaluations revealed necrosis and calcification in all specimens with the exception of the sham-operated group. CONCLUSIONS: The long-term outcomes of spermatic artery ligation were poor and testicular atrophy developed in rat testes in all study groups. Testicular atrophy could not be reversed by preoperative administration of pentoxifylline and L-NAME. 相似文献
74.
G nü l Adalioglu Ipek Tü rktas Yildiz Sara lar Ayfer Tuncer 《The Journal of asthma》1994,31(5):361-366
A double-blind, randomized, crossover study was done to determine the efficacy of colchicine in 30 atopic children with moderately severe asthma. A constant dose of sustained-release theophylline and salbutamol by inhalation, as needed, was administered to all patients. Compared to placebo, colchicine, 0.5 mg twice daily, significantly reduced morning tightness and nocturnal asthma score. There was, however, no significant difference between colchicine and placebo for cough, daytime asthma, or daily combined symptom scores for each patient. Colchicine did not significantly decrease beta-2 agonist inhaler use when compared with placebo. Similarly, there was no statistically significant difference between placebo and colchicine therapy as far as pulmonary function tests and peak flow reversibility were concerned.
Thus, colchicine administered for 4 weeks demonstrated insufficient antiasthma activity. Colchicine-induced clinical improvement that was reported in a previous study may be due to selection of patients with mild asthma symptoms. However, our group, comprised of moderately severe asthmatic patients, did not show a satisfactory clinical response. 相似文献
Thus, colchicine administered for 4 weeks demonstrated insufficient antiasthma activity. Colchicine-induced clinical improvement that was reported in a previous study may be due to selection of patients with mild asthma symptoms. However, our group, comprised of moderately severe asthmatic patients, did not show a satisfactory clinical response. 相似文献
75.
A. J. E. Raaijmakers O. Ipek D. W. J. Klomp C. Possanzini P. R. Harvey J. J. W. Lagendijk C. A. T. van den Berg 《Magnetic resonance in medicine》2011,66(5):1488-1497
Ultra high field MR imaging (≥7 T) of deeply located targets in the body is facing some radiofrequency‐field related challenges: interference patterns, reduced penetration depth, and higher Specific Absorbtion Ratio (SAR) levels. These can be alleviated by redesigning the elements of the transmit or transceive array. This is because at these high excitation field (B1) frequencies, conventional array element designs may have become suboptimal. In this work, an alternative design approach is presented, regarding coil array elements as antennas. Following this approach, the Poynting vector of the element should be oriented towards the imaging target region. The single‐side adapted dipole antenna is a novel design that fulfills this requirement. The performance of this design as a transmit coil array element has been characterized by comparison with three other, more conventional designs using finite difference time domain (FDTD) simulations and B measurements on a phantom. Results show that the B level at the deeper regions is higher while maintaining relatively low SAR levels. Also, the B field distribution is more symmetrical and more uniform, promising better image homogeneity. Eight radiative antennas have been combined into a belt‐like surface array for prostate imaging. T1‐weighted (T1W) and T2‐weighted (T2W) volunteer images are presented along with B measurements to demonstrate the improved efficiency. Magn Reson Med, 2011. © 2011 Wiley Periodicals, Inc. 相似文献
76.
Dilek Güven Ipek Ziraman Sühan Tomaç Didem Sancak M. Alp Karademir Hikmet Hasiripi 《Strabismus》2013,21(1):21-27
AIM: The aim of this study was to investigate the hemodynamic changes that may occur in the retrobulbar circulation after strabismus surgery, using color Doppler ultrasonography (CDI). METHODS. Fifteen healthy volunteers (control group, n=15) and sixteen patients diagnosed with strabismus were enrolled in the study. Either recession or resection was planned on one horizontal rectus muscle in the eyes of Group 1 (n=11) and on two horizontal rectus muscles in the eyes of Group 2 (n=10). CDI was performed to measure peak systolic velocity (V max ), end-diastolic velocity (V min ) and mean blood flow velocity (V mean ) in the ophthalmic artery (OA), central retinal artery (CRA) and posterior ciliary artery (PCA) in the control group and in Groups 1 and 2, both preoperatively and 2-7 days postoperatively. RESULTS. The postoperative resistivity indexes in Groups 1 and 2 were found to be different from those in the control group. Preoperative V max and postoperative V min and V mean values of the vessels in Group 2 were different from those in both Group 1 and the control group (p<0.001). In both treatment groups, the differences between postoperative and preoperative measurements of the parameters in the OA, CRA and PCA demonstrated statistical significance (p<0.001). CONCLUSION. After strabismus surgery on the horizontal recti, there are some alterations in the retrobulbar blood flow with a significant difference between pre- and postoperative blood flow velocities after single and double rectus surgery. The clinical significance of these results needs to be determined because CDI may be a useful tool in the investigation of hemodynamic alterations after anterior segment interventions that may cause anterior segment ischemia. 相似文献
77.
Bayazit AK Yalcinkaya F Cakar N Duzova A Bircan Z Bakkaloglu A Canpolat N Kara N Sirin A Ekim M Oner A Akman S Mir S Baskin E Poyrazoglu HM Noyan A Akil I Bakkaloglu S Soylu A 《Pediatric nephrology (Berlin, Germany)》2007,22(9):1327-1333
Renovascular disease accounts for 8–10% of all cases of paediatric hypertension, whereas, in adults, its incidence is approximately
1%. The Turkish Paediatric Hypertension Group aimed to create the first registry database for childhood renovascular hypertension
in Turkey. Twenty of the 28 paediatric nephrology centres in Turkey responded to the survey and reported 45 patients (27 girls,
18 boys) with renovascular hypertension between 1990 and 2005. The age at presentation ranged from 20 days to 17 years. The
mean blood pressure at the diagnosis was 169/110 mmHg. Chief complaints of symptomatic patients were headache (38%), seizure
(18%), epistaxis (4%), growth retardation (4%), cognitive dysfunction (4%), polyuria (2%), palpitation (2%), and hemiplegia
(2%). Renovascular hypertension was found incidentally in 11 children. The diagnosis of renovascular hypertension was established
with conventional angiography in 39 patients, MR angiography in three, CT angiography in two, and captopril diethylene triamine
penta-acetic acid (DTPA) scintigraphy in one patient. Twenty-one children had bilateral renal artery stenosis and 24 had unilateral
renal artery stenosis. Of these, 14 (31%) had fibromuscular dysplasia; 12 (27%) Takayasu’s arteritis; six (13%) neurofibromatosis;
two (5%) Williams syndrome; one (2%) Kawasaki disease; one (2%) mid-aortic syndrome; one (2%) extrinsic compression to the
renal artery, and eight (18%) unspecified bilateral renal artery stenosis. Hypertension was controlled with antihypertensive
drugs in 17 patients. Percutaneous transluminal angioplasty (PTRA) or surgery had to be performed in 28 patients: PTRA in
16 patients, PTRA + surgery in one patient and surgery in 11 patients (four nephrectomies). The importance of vasculitic disease,
especially Takayasu’s arteritis, should not be underestimated in children with renovascular hypertension. 相似文献
78.
Sahin AS Duman A Günaydin IG Sahin TK Görmüş N Duman I 《Fundamental & clinical pharmacology》2006,20(5):473-476
We studied the vasodilatory effects of fentanyl, remifentanil and sufentanil on the human saphenous vein strips at 37, 32 and 28 degrees C. Fentanyl produced concentration-dependent relaxation of human saphenous vein strips precontracted with 5-hydroxytryptamine (5-HT) at every temperature studied. Compared with vein strips at 37 degrees C, relaxant responses to each one concentration of fentanyl were significantly reduced at 32 and 28 degrees C. Remifentanil relaxed vein strips in a concentration-dependent way and the relaxation for all concentrations were significantly greater at 32 and 28 degrees C compared with 37 degrees C. Sufentanil produced concentration-dependent relaxation in saphenous vein strips precontracted with 5-HT. These relaxant responses were similar at 32 degrees C compared with 37 degrees C. When bath temperature was lowered from 37 to 28 degrees C, the relaxant responses to sufentanil were significantly reduced. In summary, the present study suggests that cooling reduces the relaxation caused by fentanyl and sufentanil on human saphenous veins but augments the relaxation with remifentanil. The augmented vasodilatory effect of remifentanil with cooling may be useful on systemic vascular resistance and organ preservation under hypothermic conditions like cardiopulmonary bypass surgery. 相似文献
79.
There is a need to have an appropriate instrument to measure the attitudes towards nursing profession. This study was carried out to develop an Attitude Scale for Nursing Profession (ASNP). The population of the study is composed of final-year students of high schools, the patients, the nurses and students of nursing department. A total of 600 participants were included in this study. The people in the sampling group were asked to write a composition containing their feelings and thoughts about nursing. These compositions were analysed and 89 items about positive and negative attitude were determined. These items were presented to expert opinion and after necessary editions, reliability and validity analyses were conducted. The resulting ASNP consists of 40 items across the following three domains: properties of nursing profession prefer to nursing profession, general position of nursing profession. The final model in confirmatory factor analysis showed that this 40-item ASNP indicated a good fit of the model. The value of the Cronbach's α for the total scale was 0.91. The ASNP is determined to be quite highly valid and reliable, sufficient measuring instrument to determine attitude towards the profession. 相似文献