全文获取类型
收费全文 | 21172篇 |
免费 | 1018篇 |
国内免费 | 138篇 |
专业分类
耳鼻咽喉 | 219篇 |
儿科学 | 320篇 |
妇产科学 | 337篇 |
基础医学 | 2769篇 |
口腔科学 | 395篇 |
临床医学 | 1344篇 |
内科学 | 5664篇 |
皮肤病学 | 332篇 |
神经病学 | 1570篇 |
特种医学 | 1064篇 |
外科学 | 3761篇 |
综合类 | 123篇 |
预防医学 | 556篇 |
眼科学 | 335篇 |
药学 | 1361篇 |
4篇 | |
中国医学 | 62篇 |
肿瘤学 | 2112篇 |
出版年
2023年 | 130篇 |
2022年 | 100篇 |
2021年 | 454篇 |
2020年 | 246篇 |
2019年 | 318篇 |
2018年 | 400篇 |
2017年 | 345篇 |
2016年 | 424篇 |
2015年 | 432篇 |
2014年 | 543篇 |
2013年 | 627篇 |
2012年 | 1118篇 |
2011年 | 1266篇 |
2010年 | 649篇 |
2009年 | 602篇 |
2008年 | 1046篇 |
2007年 | 1241篇 |
2006年 | 1217篇 |
2005年 | 1253篇 |
2004年 | 1228篇 |
2003年 | 1220篇 |
2002年 | 1174篇 |
2001年 | 519篇 |
2000年 | 519篇 |
1999年 | 533篇 |
1998年 | 350篇 |
1997年 | 285篇 |
1996年 | 239篇 |
1995年 | 243篇 |
1994年 | 155篇 |
1993年 | 172篇 |
1992年 | 282篇 |
1991年 | 280篇 |
1990年 | 293篇 |
1989年 | 280篇 |
1988年 | 276篇 |
1987年 | 266篇 |
1986年 | 221篇 |
1985年 | 186篇 |
1984年 | 156篇 |
1983年 | 114篇 |
1982年 | 64篇 |
1981年 | 56篇 |
1980年 | 49篇 |
1979年 | 96篇 |
1978年 | 49篇 |
1976年 | 51篇 |
1972年 | 63篇 |
1970年 | 47篇 |
1969年 | 59篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
2.
3.
4.
Yasushi Sawayama Hidehiro Itonaga Takuya Fukushima Nobuaki Nakano Hiroshi Fujiwara Atae Utsunomiya Takahiro Fukuda Toshihiro Miyamoto Tetsuya Eto Kaname Miyashita Hirohisa Nakamae Masao Ogata Atsushi Yamanoha Yasuhiko Miyazaki Junya Kanda Yoshiko Atsuta Koji Kato ATL Working Group of the Japan Society for Hematopoietic Cell Transplantation 《American journal of hematology》2019,94(5):E143-E146
5.
Mitsuhiro Tozaki Kunihiko Fukuda Masafumi Suzuki 《Magnetic resonance in medical sciences》2006,5(3):137-146
PURPOSE: The purpose of this study was to assess the relationship between the amount of scirrhous component in invasive ductal carcinoma and its MR characteristics. MATERIALS AND METHODS: We retrospectively reviewed 71 consecutive patients with invasive ductal carcinoma smaller than 25 mm (average, 16.6 mm) in diameter. The scirrhous component was defined as invasive foci in small clusters of cancer cells showing desmoplasia. Invasive ductal carcinoma was subclassified into 3 groups in accordance with the amount of the scirrhous component (scirrhous component degree; SCD): SCD I (scirrhous component less than 20%), SCD II (intermediate), and SCD III (more than 80%). Dynamic magnetic resonance (MR) imaging was performed using volumetric interpolated sequence. Prior to dynamic study, T2*-weighted first-pass perfusion images were obtained before, during, and after bolus injection of 0.1 mmol Gd-DTPA/kg. RESULTS: Twenty-eight lesions were classified as SCD I, 14 as SCD II, and 29 as SCD III. Mass margin and signal intensity loss in the perfusion study were significantly different among the 3 SCD groups (P<0.001). The kinetic patterns were significantly different among the 3 SCD groups (P=0.04), and between SCD I/II and SCD III (P=0.03). The presence of enhancing internal septations was significantly different between SCD I/II and SCD III carcinomas (P=0.05). Central enhancement was only observed in SCD I carcinoma (4%; 3/71). CONCLUSION: The histological predominance of the scirrhous component in invasive ductal carcinoma may be one explanation for the differences in morphologic and kinetic patterns on MR imaging. 相似文献
6.
Yuzuru Takemura Haku Ishida Yuji Inoue 《Clinical chemistry and laboratory medicine》2003,41(5):668-674
Few studies have demonstrated the optimal usage of common inflammatory markers, alone or in combination, based on the cost-effectiveness. We analyzed the yield and cost of C-reactive protein (CRP), white blood cell count (WBC), erythrocyte sedimentation rate (ESR), sialic acid, and protein fractionation in 177 new primary care outpatients with inflammation-related symptoms. A useful result (UR) was assigned if tests contributed to a change in physician's diagnosis or decision-making. Costs of testing were calculated based on either single or simultaneous measurement. Five inflammatory markers generated 147 URs in 123 patients. CRP showed the best contribution to generation of UR, followed by sialic acid, protein fractionation, WBC, and ESR. CRP demonstrated poor correlation with WBC (r = 0.458), while sialic acid strongly correlated with total absolute amount of alpha1 and alpha2 fractions in protein fractionation (r = 0.855) and moderately with ESR (r = 0.651). The combination of CRP and WBC produced the best cost-effectiveness at a cost of Yen 1169 (US dollars 9.6 or Euro 9.7)/additional UR against CRP testing alone. Sialic acid, an automated multichannel analyzer-based test, demonstrated the favorable cost-effectiveness over ESR or protein fractionation when combined with CRP (and WBC). Our results indicate that the optimal usage of these inflammatory markers should involve careful cost-effectiveness considerations. 相似文献
7.
Endoscopic anterior cruciate ligament reconstruction using a computer-assisted fluoroscopic navigation system 总被引:3,自引:0,他引:3
Hisatada Hiraoka Sou Kuribayashi Akira Fukuda Naoshi Fukui Kozo Nakamura 《Journal of orthopaedic science》2006,11(2):159-166
Background During anterior cruciate ligament (ACL) reconstruction, placement of the reconstructed ligament affects the clinical results.
To accomplish accurate and reproducible placement of the tibial bone tunnel, we employed a fluoroscopic navigation system
for endoscopic ACL reconstruction. In this study, preciseness of the tibial tunnel placement was evaluated, and the advantages
and disadvantages of this navigation system for endoscopic ACL reconstruction are discussed.
Methods Altogether, 16 knees of 16 patients who had undergone ACL reconstruction using this system (navi group) were evaluated regarding
the positioning of the tibial tunnel against Blumensaat's line using X-p and the route of the graft by magnetic resonance
imaging (MRI). Another 16 knees of 16 patients who underwent endoscopic ACL reconstruction without the navigation system were
the controls (control group).
Results At the 1-year follow-up, maximally extended lateral knee X-p revealed that the anterior edge of the tibial tunnel and Blumensaat's
line were almost aligned and that roof impingement was avoided; the T2-weighted MR images showed that the graft was placed
close to and parallel to the intercondylar roof in all the knees of the navi group. The ratio of the distance between Blumensaat's
line and the anterior edge of the tibial tunnel at the level of the tibial plateau to the anteroposterior width in fully extended
true lateral radiographs was 2.7% ± 3.4% in the navi group and 8.4% ± 7.4% in the control group.
Conclusions The computer-assisted fluoroscopic navigation system improves accuracy and decreases dispersion of the tibial tunnel placement
against Blumensaat's line in single-bundle ACL reconstruction. This innovative device renders the reconstruction procedure
more reliable, eliminating the problem of skeletal variation among patients. However, the function of this navigation system
for femoral tunnel placement is insufficient at present. Further refinement of the system is necessary, and the method of
application requires improvement. 相似文献
8.
Yasuyuki Suzuki Kazuyuki Daitoku Masahito Minakawa Kozo Fukui Ikuo Fukuda 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2006,54(1):44-46
We report the case of a 4-year-old girl who had quadricuspid aortic valve regurgitation with tetralogy of Fallot and pulmonary
atresia. This combination is very uncommon. Aortic valve replacement was performed successfully due to aortic regurgitation
which had progressed one year after the total repair. The dilated aortic annulus plus quadricuspid aortic valve may result
in progressive aortic regurgitation for a short period. 相似文献
9.
Yuji Morimoto Osamu Kemmotsu Koichi Kitami Izumi Matsubara Ichiro Tedo 《Journal of anesthesia》1995,9(1):22-26
We evaluated whether we could predict the neurologic outcome in 55 out-of-hospital cardiac arrest patients using auditory
brainstem responses (ABR). ABR patterns were classified into one of 3 types by evaluation of 5 components: type 1, with all
5 components; type 2, lack of at least one response between the 2nd and 5th components; type 3, with only the first component
or no response. The relation between the ABR patterns on the 3rd day following resuscitation and the neurologic outcome on
hospital discharge was evaluated. The specificity that the 5 awake patients had type-1 ABR was 38%. The sensitivity that the
10 brain dead patients had type-3 ABR was 60%. In the type-1 ABR patients, the negative predictive value that the patients
were awake was 100%. In the type-3 ABR patients, the negative predictive value that the patients became brain dead was 90.9%.
These results suggest that ABR on the 3rd post-resuscitation day may not be useful for predicting if patients are awake or
become brain dead, although the loss of components may be a sign of morbidity, and the presence of the 2nd or later components
indicates possible future prevention of brain death. 相似文献
10.
Experiments were performed on spinalized rats, transected at the Cl level. The intravenous administration of TRH and its analog YM-14673 (N alpha-[(S)-4-oxo-2-azetidinyl) carbonyl]-L-histidyl-L-prolinamide dehydrate) produced marked increases in the amplitude of mono- and polysynaptic reflex potentials and those of the withdrawal flexor reflexes. The effects of YM-14673 were stronger and longer-lasting than those of TRH. The stimulant action of TRH and YM-14673 on the flexor reflexes was not antagonized by prazosin, chlorpromazine, haloperidol or cyproheptadine, suggesting no involvement of the release of catecholamines or serotonin in the stimulant effects of TRH and its analog. Therefore, YM-14673 may be beneficial for the treatment of several spinal motor neuron diseases. 相似文献