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961.
PURPOSE: The dynamics of ophthalmic ointment on the ocular surface were investigated using a fluorescent ointment. METHODS: Ten healthy volunteers were enrolled. Ointment (1.0 cm length, 0.05 g) containing 0.1% flavin adenine dinucleotide sodium was squeezed out from the tube and placed in the left lower conjunctival sac. The eyes were then closed for 30 seconds and permitted to blink naturally. Two examinations including observation of tear film lipid layer interference pattern and fluorophotometric measurement of fluorescence intensity, both at the center of the cornea, were performed before examination and at 1, 3, 6, 9, 12, 15, 30, 60 minutes after instillation. RESULTS: In all cases, even 1 hour after instillation, tear film interference patterns were observed, and fluorescence intensity greater than before instillation, was present. CONCLUSION: Ointment placed in the conjunctival sac is thought to remain and release agents on the ocular surface for at least one hour. 相似文献
962.
Maruyama K Yokoi N Takamata A Kinoshita S 《Investigative ophthalmology & visual science》2004,45(8):2563-2568
PURPOSE: Dry eye symptoms are often associated with soft contact lens (SCL) wear and may be affected by environmental conditions. This study was conducted to determine the effects of temperature and humidity on the tear film in SCL wearers. METHODS: All 11 enrolled subjects were males (mean age, 23.5 +/- 5.2 [SD] years), and all wore SCL daily. They were exposed in different sessions to four different conditions in an environmental chamber with the air temperature (AT) and relative humidity (RH) set at 5 degrees C/10% (AT/RH), 15 degrees C/20%, 25 degrees C/40%, or 35 degrees C/50%. Two different types of hydrogel SCL (SCL-a and SCL-b; water content 72.0% and 37.5%, respectively) were used. The meniscus tear volume was determined on a video meniscometer by measuring the tear meniscus radius (TMR) with and without SCL. The tear interference patterns on the contact lens (TIPCL) were classified into five grades (the higher the grade, the thinner the film). Using a video interferometer, the non-invasive tear film breakup time (NIBUT) was recorded with and without SCLs; ocular dryness was also scored with and without SCLs. RESULTS: Under the environmental conditions examined, there were no significant differences in the TMR without or with SCL, regardless of their type. As AT and RH decreased, there was a significant increase in the TIPCL grade (CL-a: P = 0.042; CL-b: P = 0.002), a significant decrease in NIBUT (CL-a: P = 0.004; CL-b: P = 0.001), and a significant increase in the dryness score (without SCL P = 0.023; with CL-a P = 0.009; with CL-b P = 0.003). The dryness scores were higher with CL-a than CL-b (P = 0.011 at 15 degrees C/20%). Under identical experimental conditions, we observed no significant change in NIBUT in the absence of an SCL. CONCLUSIONS: AT and RH apparently had no effect on the tear volume in the presence of SCLs. As AT and RH decreased, the tear film on the SCL became thinner, NIBUT became shorter, and dryness increased. Dryness was more pronounced in eyes with SCL of the higher water content. 相似文献
963.
Honda N Hamada N Amano S Kaji Y Hiraoka T Oshika T 《Journal of refractive surgery (Thorofare, N.J. : 1995)》2004,20(2):116-120
PURPOSE: To analyze long-term results of photorefractive keratectomy (PRK) for myopia and myopic astigmatism. METHODS: This retrospective study included 15 eyes of 8 patients who were examined annually for 5 years after PRK. The Nidek EC-5000 laser with an ablation zone of 5.0 mm was used. Evaluations included spherical equivalent manifest refraction, uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), corneal haze, and corneal astigmatism calculated by Fourier analysis of videokeratography data. RESULTS: A tendency toward myopic regression was most evident within the first postoperative year, with manifest refraction changing from +0.80 +/- 1.62 D at 1 week to -0.45 +/- 0.70 D at 1 year postoperatively (P = .007). Regression continued after the second postoperative year. There was a statistically significant difference between manifest refraction at 2 years (-0.36 +/- 0.75 D) and 5 years (-1.11 +/- 1.12 D) (P = .002). Postoperative UCVA stabilized from 3 months up to 3 years, but slightly deteriorated at 4 years and thereafter due to the myopic refractive shift. BSCVA remained stable throughout the 5-year follow-up period. Several eyes developed mild corneal haze after surgery, but haze was minimal in the majority of patients by 1 year and continued to fade over time. The asymmetry component of the cornea significantly increased after surgery, with all postoperative values significantly higher than before PRK (P < .05). Higher order irregularity increased after surgery, with a statistically significant difference between preoperative and 1 year postoperative (P < .05), but values after 2 years were not different from preoperative baseline. CONCLUSION: Fifteen eyes with a baseline refraction of -3.00 to -9.00 D had PRK with the Nidek EC-5000 laser and a 5-mm-diameter ablation zone. Myopic regression occurred in the first year, with continued mild regression of approximately -0.75 D between 2 and 5 years. Nevertheless, the results show the procedure was relatively safe and effective in this group. 相似文献
964.
Kumazawa T Tsuchiya N Wang L Sato K Kamoto T Ogawa O Nakamura A Kato T Habuchi T 《International journal of cancer. Journal international du cancer》2004,110(1):140-144
It is widely recognized that androgen biosynthesis and metabolism are associated with the development and progression of prostate cancer. The human CYP11A1 gene (CYP11A1) encodes the P450scc enzyme, which mediates the first step in sex steroid hormone synthesis. The gene contains a (tttta)n-5 bp tandem repeat microsatellite polymorphism located at 528 bp upstream of the translation initiation site and the CYP11A1 mRNA level may be modulated by the polymorphism. Recent studies suggested that the absence of the shortest (tttta)4 allele of the CYP11A1 polymorphism was associated with a risk of polycystic ovary syndrome and with a hyperandrogenic state in polycystic ovary syndrome patients. In our study which included 278 prostate cancer patients, 213 benign prostatic hyperplasia (BPH) patients and 299 male controls, we explored the association between the CYP11A1 polymorphism and prostate cancer on the hypothesis that the presence of the (tttta)4 allele may increase the risk of the development or progression of prostate cancer. In addition, we measured the serum levels of 6 steroid hormones or their metabolite (i.e., testosterone, free-testosterone, estrone, estradiol, dehydroepiandrosterone and androstendione) in 156 control males subjects and compared those with and without the (tttta)4 allele. The polymorphism was evaluated by PCR amplification of a 145-170 bp fragment followed by polyacrylamid gel electrophoresis. The CYP11A1 allele consisted of 4, 6, 7, 8 and 9 (tttta)-5 bp repeats. There was no significant difference in the genotype frequency as for the presence of the (tttta)4 allele between prostate cancer patients and male controls, and between prostate cancer patients and BPH patients. However, there was a significant difference in the genotype frequency in relation to the disease status. Prostate cancer patients without the (tttta)4 allele had an increased risk of metastatic disease (stage D) compared to those with the (tttta)4 allele [adjusted odds ratio (aOR)=1.76, 95% confidence interval (Cl)=1.07-2.90 and p =0.026]. Patients without the (tttta)4 allele had an increased risk of high grade prostate cancer (Gleason score 8 or more, or poorly differentiated cancer) compared to those with the (tttta)4 allele (aOR=1.79, 95% Cl=1.08-2.97 and p =0.025). No significant difference in the serum levels of 6 steroid hormones or their metabolites was found in the presence or absence of the (tttta)4 allele. Our results suggest that the CYP11A1 polymorphism may have a significant influence on the development of advanced and/or high grade prostate cancer and the absence of the CYP11A1 (tttta)4 allele, i.e., the homozygosity for the (tttta)6 or longer allele, could be a useful marker for the prediction of disease progression of prostate cancer. 相似文献
965.
Emura T Suzuki N Yamaguchi M Ohshimo H Fukushima M 《International journal of oncology》2004,25(3):571-578
TAS-102 is a new antimetabolite agent composed of a alpha, alpha, alpha-trifluorothymidine (FTD; 1 M) and thymidine phosphorylase inhibitor (TPI; 0.5 M). Here, we investigated the antitumor effect and mechanism of TAS-102 against 5-FU, or FdUrd, resistant human cancer cell lines. The respective tumor growth inhibition rate of orally administered FTD against 5-FU-resistant NUGC-3 was about 70% at a dose level of 200 mg/kg/day; this value was comparable to that against the parental NUGC-3. On the other hand, the tumor inhibition rates of 5-FU, FdUrd, and TS-1 against 5-FU-resistant NUGC-3 were lower than those against parental NUGC-3. Similar observations were made in an FdUrd-resistant human colorectal cancer cell line (DLD-1). TAS-102 was also effective in 5-FU-less sensitive human pancreatic cancer cell lines (PAN-12 and BxPC-3) and human esophagus cancer (T.T.) when compared with 5-FU or UFT. Our hypothesis was that a relatively short and high dosage of TAS-102 results in an additional mechanism of FTD incorporation into DNA other than thymidylate synthase (TS) inhibition. We then examined the effects of FTD on DNA at the cellular level. After treatment with FTD or FdUrd, the DNA fragmentation pattern was examined using filter elution and in situ nick translation. Treatment with FTD for 2 h resulted in marked DNA fragmentation. When the tumor cells were treated with FTD for 72 h or with FdUrd for 2 or 72 h, only a small amount of DNA fragmentation was observed, and the appearance of the tumor cells did not differ markedly from that of untreated cells. Moreover, the DNA fragmentation rate in the TAS-102 treatment group was significantly higher than that in the control group in vivo. These results suggest that when tumor cells are exposed to high concentrations of FTD for short periods of time, FTD manifests its antitumor activity primarily through the induction of DNA fragmentation after FTD incorporation into the DNA. We conclude that TAS-102 is expected to manifest antitumor effects against 5-FU-resistant tumors that are similar to those exerted in 5-FU-sensitive tumors. 相似文献
966.
T393C polymorphism of GNAS1 associated with the autonomic nervous system in young, healthy Japanese subjects 总被引:2,自引:0,他引:2
Yasuda K Matsunaga T Moritani T Nishikino M Gu N Yoshinaga M Nagasumi K Yamamura T Aoki N Tsuda K 《Clinical and experimental pharmacology & physiology》2004,31(9):597-601
1. T393C polymorphism of the gene encoding the Gs-protein alpha-subunit (GNAS1) has been reported recently to be associated with hypertension in which dysfunctions of the autonomic nervous system (ANS) are closely involved. In the present study, the association of this polymorphism with ANS activity was investigated in young, healthy Japanese males. 2. Four hundred and one subjects were genotyped for the T393C polymorphism of GNAS1 by polymerase chain reaction-restriction fragment length polymorphism. Autonomic nervous system activity during supine rest and when standing was assessed in 137 subjects by electrocardiogram R-R interval power spectral analysis. 3. One hundred and fifty-four subjects (38.4%) were homozygous for the T allele (TT), 188 (46.9%) were heterozygous (TC) and 59 (14.7%) were homozygous for the C allele (CC). There were no significant differences as to genotype among the clinical characteristics investigated. In power spectral analysis of heart rate variability, the high-frequency component and parasympathetic nervous system (PNS) index during supine rest were significantly lower in TT and TC carriers than in CC carriers. Furthermore, the increase in heart rate and the responsiveness of sympathetic nervous system index and PNS index to postural change from supine rest to standing were significantly lower in TT and TC carriers than in CC carriers. 4. These observations suggest that the GNAS1 T393C polymorphism is associated with ANS activity in youth, so that it may be useful as a genetic marker for future pathogenesis of hypertension. Follow-up studies are necessary to clarify the prevalence rates of hypertension among 393T allele carriers in the present study. 相似文献
967.
Kitaya N Hikichi T Kagokawa H Takamiya A Takahashi A Yoshida A 《American journal of ophthalmology》2004,138(2):308-310
PURPOSE: To investigate the association between a photoreceptor irregularity and visual acuity (VA) after macular hole (MH) surgery. DESIGN: Prospective observational case series. METHODS: Twenty-four eyes with an idiopathic MH that resolved after vitreous surgery were examined by new optical coherence tomography (OCT 3000). The images were divided into regular photoreceptor, detected as a straight line above the retinal pigment epithelium reflex, and irregular, which cannot be detected by it. RESULTS: Regular images were observed in 12 eyes (80%) and irregular images in 3 eyes (20%) with good VA (>or=0.7). Regular images were seen in 3 eyes (33%) and irregular images in 6 eyes (67%) with poor VA (<0.7). The percentage of regular images in the group with good VA was significantly higher than that in the group with poor VA (P <.05). CONCLUSION: A photoreceptor irregularity after MH surgery may prevent VA improvement. 相似文献
968.
Tsunezuka Y Iseki T Sato H Ishikawa N Oda M Watanabe G 《Asian cardiovascular & thoracic annals》2004,12(3):224-226
The Poly-L-lactide costal coaptation pin is an effective device in chest wall reconstruction. However, fixation is sometimes incomplete, despite the use of the costal coaptation pin. We report here the use of two suture techniques for the fixation of the incised ribs with costal coaptation and discuss the effectiveness of these procedures. We used the Poly-L-lactide costal coaptation pin in 174 cases of posterolateral thoracotomies with two suture methods. In one method the rib was generally fixed with suture only (L-method, n = 30), and in the H-method pairs of holes were made at the end of the incised ribs for ligating with sutures (H-method, n = 144). The effectiveness of each method was evaluated based on the degree of fixation and lateral shift 24 months postoperatively. Lateral shift was none in 114 (79.2%) cases using the H-method and 18 (60.0%) cases using the L-method. Fixation was good in 131 (91.0%) cases using the H-method but in only 20 (66.7%) cases using the L-method. H-method was significantly more effective than the L-method of costal coaptation. The H-method was very effective for fixing incised ribs and is convenient for use by thoracic surgeons. 相似文献
969.
970.
Ikeda N Maeda J Yashima K Tsuboi M Kato H Akada S Okada S 《The Annals of thoracic surgery》2004,78(3):1011-1016