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71.
Growth suppression of non-small cell lung carcinoma cells by the introduction of the p16(INK4A) gene
The p16(INK4A) gene is frequently inactivated in nonsmall cell lung carcinoma (NSCLC) by either mutations, deletions or DNA methylations. To assess the biological significance of p16(INK4A) inactivation in the development of NSCLC, full-length p16(INK4A) cDNA was introduced into NSCLC cell lines, A549 and H322, in which p16(INK4A) was homozygously deleted. NSCLC cells transfected with the p16(INK4A) expression vector formed colonies in 20-68% of those with a control vector, and exogenous p16(INK4A) protein was expressed in 4 of 68 A549-derived clones and none of 29 H322-derived clones, respectively. A549-derived clones which stably expressed the exogenous p16(INK4A) gene showed significant decrease in growth rate in vitro and tumorigenicity in vivo in proportion to the level of p16(INK4A) expression. Furthermore, the cell cycle of these cells significantly delayed with accumulation of cells in G1 phase. Micro-injection of p16(INK4A) expression vector also revealed that p16(INK4A) blocked S phase entry in both A549 and H322 cells. These results suggest that the restoration of the p16(INK4A) function suppresses the growth of NSCLC cells by induction of G1 arrest in the cells. Therefore, inactivation of p16(INK4A) may play an important role in the enhancement of unregulated NSCLC growth in vivo. 相似文献
72.
Summary The incidence of high cervical disc lesions is extremely rare, and the mechanism of their development is unclear. We report
these three cases, and discuss the possible mechanisms. We also describe surgical strategies for these lesions.
The first and second cases were an 82-year-old male and an 84-year-old male with retro-odontoid disc hernia. The third was
an 83-year-old female with a herniated disc at C2/C3. To investigate Aetiological mechanisms of these lesions, we examined
the findings on cervical images in extension and flexion, and compared the results in a younger than 80-year-old group and
an older than 80-year-old group.
The patients underwent surgery via a posterolateral intradural approach. Wide laminectomy and incision of the dentate ligaments
enabled access to the ventral space of the upper cervical spinal canal and sufficient decompression. All patients became ambulatory
postoperatively without special fixation of the cervical spine. In the younger group, the level mostly loaded during cervical
movement was C5/6, however, the levels in the older group were C2/3 and C3/4.
In elderly patients, less mobilization of the middle and/or lower cervical spine due to spondylotic change causes overloading
at higher levels resulting in high cervical disc lesions. Retro-odontoid disc lesions can be caused by a herniated disc at
C2/C3, which migrates upward. Regarding surgical strategy, the posterolateral intradural approach is less invasive and more
advantageous for these lesions. 相似文献
73.
Endovascular treatment of ruptured dissecting aneurysms aimed at occlusion of the dissected site by using Guglielmi detachable coils 总被引:13,自引:0,他引:13
Yamaura I Tani E Yokota M Nakano A Fukami M Kaba K Matsumoto T 《Journal of neurosurgery》1999,90(5):853-856
OBJECT: Surgical or endovascular occlusion of the parent artery proximal to an aneurysm has been recommended for treatment of dissecting aneurysms of the intracranial posterior circulation. However, dissecting aneurysms may rupture even after proximal occlusion because distal progression of thrombus is necessary to occlude the dissecting aneurysm completely, and this may be delayed by the presence of retrograde flow. In this article the authors present their experience in treating six patients with ruptured dissecting aneurysms. METHODS: The authors report on six patients with a ruptured dissecting aneurysm in the posterior fossa who were successfully treated by endovascular occlusion of the aneurysm by using Guglielmi detachable coils. The procedure was particularly aimed at occluding the dissected site. CONCLUSIONS: At the present time, endovascular occlusion of the dissected site is a safe, minimally invasive, and reliable treatment for dissecting aneurysms when a test occlusion is tolerated and adequate collateral circulation is present. 相似文献
74.
75.
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77.
Aneurysm of persistent primitive hypoglossal artery 总被引:2,自引:0,他引:2
A patient with a ruptured intracranial aneurysm of the right persistent primitive hypoglossal artery is described. Clipping of the aneurysmal neck was achieved by a far lateral approach together with drilling of the jugular tubercle, and it was concluded that this approach should be followed for safe and complete clipping. 相似文献
78.
OBJECTIVE: To investigate the effect of sodium, protein and calcium in habitual diets on bone resorption. DESIGN: A cross-sectional study. SETTING: A community-based study. SUBJECTS: Healthy free-living male (n=342) and female (n=421) volunteers aged 20-79 y recruited for a health and nutrition examination survey conducted by a local government. METHODS: Bone resorption was assessed by the measurement of free deoxypyridinoline in 24 h urine. Dietary assessment was by one-day dietary record method. Sodium and urea in 24 h urine were also measured for assessment of sodium and protein intake. The relationships between deoxypyridinoline excretion and the dietary factors were examined using correlation and multiple regression statistics. RESULTS: In women aged 50-79 y, protein intake was positively associated with deoxypyridinoline excretion (P<0.05); and the urinary deoxypyridinoline/creatinine ratio was positively associated with both the urinary calcium/creatinine ratio (P<0.01) and sodium/creatinine ratio (P<0.05). In the multiple regression model, the association of the deoxypyridinoline/creatinine ratio and sodium/creatinine ratio was still significant (P<0.05) after adjustment for possible confounders, in this sex and age group. CONCLUSION: In elderly women, habitual excess sodium in diets may result in bone loss through accelerated bone resorption. 相似文献
79.
Yokota K Johyama Y Yamaguchi K Fujikt Y Takeshita T Morimoto K 《Environmental health and preventive medicine》1996,1(3):133-135
Methylterahydrophthalic anhydride (MTHPA) is used as a hardening agent in an epoxy resin system. Because work-related nasal symptoms were observed in some workers exposed toMTHPA at two condenser plants, a cross-sectional survey was performed to improve their work environment. MeanMTHPA levels in the manufacturing processes to which the workers were routinely assigned were extremely low (1.09-22.4 μg/m3). However, specific IgE antibody (S-IgE) was detected in 9 (32%) of 28 workers. Of these, 8 (89%) had nasal symptoms. An IgE-mediated mechanism seems to be associated with at least some of the cases of work-related nasal symptoms. This indicates that the occupational health administration ofMTHPA cannot be controlled simply by limiting exposure in the work environment. Total IgE (T-IgE) levels were significantly higher in S-IgE-positive workers than in S-IgE-negative workers (geometric mean, 200.5 and 51.3 IU/ml, respectively; p<0.002, unpaired t test). These findings demonstrate that workers in whom S-IgE is less likely to be produced, i.e., those in whom the T-IgE level is 80 IU/ml or less, should be assigned to work in these manufacturing processes. 相似文献
80.