全文获取类型
收费全文 | 6360篇 |
免费 | 303篇 |
国内免费 | 51篇 |
专业分类
耳鼻咽喉 | 62篇 |
儿科学 | 105篇 |
妇产科学 | 73篇 |
基础医学 | 785篇 |
口腔科学 | 110篇 |
临床医学 | 378篇 |
内科学 | 1421篇 |
皮肤病学 | 112篇 |
神经病学 | 486篇 |
特种医学 | 345篇 |
外科学 | 1329篇 |
综合类 | 21篇 |
预防医学 | 174篇 |
眼科学 | 52篇 |
药学 | 396篇 |
中国医学 | 7篇 |
肿瘤学 | 858篇 |
出版年
2023年 | 43篇 |
2022年 | 101篇 |
2021年 | 189篇 |
2020年 | 77篇 |
2019年 | 139篇 |
2018年 | 128篇 |
2017年 | 123篇 |
2016年 | 166篇 |
2015年 | 147篇 |
2014年 | 211篇 |
2013年 | 211篇 |
2012年 | 342篇 |
2011年 | 391篇 |
2010年 | 222篇 |
2009年 | 191篇 |
2008年 | 288篇 |
2007年 | 305篇 |
2006年 | 333篇 |
2005年 | 368篇 |
2004年 | 353篇 |
2003年 | 343篇 |
2002年 | 355篇 |
2001年 | 148篇 |
2000年 | 154篇 |
1999年 | 152篇 |
1998年 | 78篇 |
1997年 | 79篇 |
1996年 | 74篇 |
1995年 | 60篇 |
1994年 | 54篇 |
1993年 | 46篇 |
1992年 | 86篇 |
1991年 | 93篇 |
1990年 | 105篇 |
1989年 | 79篇 |
1988年 | 51篇 |
1987年 | 53篇 |
1986年 | 52篇 |
1985年 | 43篇 |
1984年 | 31篇 |
1983年 | 24篇 |
1980年 | 16篇 |
1979年 | 18篇 |
1978年 | 13篇 |
1973年 | 19篇 |
1972年 | 13篇 |
1970年 | 16篇 |
1969年 | 18篇 |
1968年 | 14篇 |
1967年 | 15篇 |
排序方式: 共有6714条查询结果,搜索用时 31 毫秒
1.
Takao Itoi Atsushi Sofuni Fumihide Itokawa Yasushi Shinohara Kazuya Takeda Kazuto Nakamura Toshio Kurihara Takayoshi Tsuchiya Fuminori Moriyasu 《Digestive endoscopy》2006,18(3):232-238
We describe our methods and outcomes of multidisciplinary treatments in patients with unresectable hilar cholangiocarcinoma. Fifty‐seven patients with a known outcome were enrolled. Thirty‐four of 57 patients were treated and evaluated by salvage therapy. For salvage therapy, we used internal and external radiotherapy, photodynamic therapy, YAG laser therapy and microwave coagulation therapy. The median survival time was 548 days for the group receiving salvage therapy and 198 days for the group not receiving this treatment. In conclusion, although no randomization of the patients was performed in this retrospective study, our present data provide convincing evidence that salvage therapy is a useful therapeutic approach for unresectable hilar cholangiocarcinomas. 相似文献
2.
High incidence of nitrosamine-induced tumorigenesis in mice lacking DNA repair methyltransferase 总被引:12,自引:4,他引:8
Iwakuma T; Sakumi K; Nakatsuru Y; Kawate H; Igarashi H; Shiraishi A; Tsuzuki T; Ishikawa T; Sekiguchi M 《Carcinogenesis》1997,18(8):1631-1635
The enzyme O6-methylguanine-DNA methyltransferase repairs alkylation-
induced DNA damage, O6-methylguanine and O4-methylthymine, the former being
formed more frequently. Previously, by means of gene targeting, we
generated mice in which alleles for methyltransferase were disrupted. We
now use these mouse lines, which are totally deficient in methyltransferase
activity, to examine protective effects of the enzyme against tumor
formation. In gene-targeted female mice given an i.p. injection of 5 mg/kg
of dimethylnitrosamine, a larger number of liver and lung tumors occurred,
as compared with normal female mice treated in the same manner. In male
mice given a lower dose of carcinogen, the difference between normal and
gene-targeted mice was statistically insignificant although more tumors did
form in the gene-targeted mice. Methyltransferase apparently afforded
protection from nitrosamine- induced tumorigenesis.
相似文献
3.
I Nochide S Ohta T Ueda M Shiraishi H Watanabe S Sakaki J Ikezoe 《AJNR. American journal of neuroradiology》1998,19(9):1669
BACKGROUND AND PURPOSETo detect areas of cerebral perfusion from bypass arteries after vascular reconstruction, we administered selective intraarterial microsphere tracer into the external carotid arteries and determined (via single-photon emission computed tomography [IA-SPECT]) whether the distribution of radiotracer matched the arteriographic distribution of contrast material as shown on external carotid angiograms.METHODSWe compared the extent of regional distribution of tracer after external carotid artery injection of 20 to 40 MBq of 99mTc-HMPAO or 99mTc-ECD with that of contrast medium on the external carotid angiograms in 582 cortical regions in 12 patients with atherosclerotic occlusive disease and in 18 patients with moyamoya disease.RESULTSMarked accumulation of tracer was found only in the expected, specific, newly developed areas of cerebral perfusion from bypass arteries. The regional distribution of tracer corresponded to that of contrast medium in 523 regions (90%) and did not correspond in 59 regions (10%). Significant overestimation of the distribution of contrast material relative to that of tracer was observed in the patients with moyamoya disease.CONCLUSIONSPECT showed slightly different distribution of tracer from that predicted by conventional angiography. IA-SPECT should enhance the analysis of newly developed areas of cerebral perfusion from the bypass arteries. 相似文献
4.
Joe Matsumoto Tetsufumi Kojima Tetsuya Shimizu Shuji Kitashiro Kazuya Konishi Yoshiyuki Matsumura You Kawarada Hitoshi Ikeda Takashi Yoshiki 《Annals of thoracic and cardiovascular surgery》2002,8(3):151-153
In lung cancer patients, hypercalcemia is a fairly common metabolic problem associated with malignancy. However, the occurrence of hypercalcemia in lung cancer patients means an ominous prognostic sign. As hypercalcemia often causes early death, quick diagnosis and treatment for hypercalcemia are required. A 69-year-old woman was admitted to our hospital with anorexia caused by hypercalcemia. On admission, serum level of PTH was elevated and PTHrP was normal. From the results of CT findings and transbronchial lung biopsy, the cause of the hypercalcemia was determined as lung cancer incidentally complicated with primary hyperparathyroidism. First, serum calcium level was returned to normal through hydration with saline and bisphosphonates. Next, left hemithyroidectomy for primary hyperparathyroidism was performed. Histologically, the tumor was diagnosed as parathyroid adenoma. Fifteen days later, left lower lobectomy for primary lung cancer was performed under a video-assisted thoracoscopic approach. Histologically, the tumor was diagnosed as a moderately differentiated adenocarcinoma. Four years and three months after the operation, the patient is alive and well with no sign of recurrence. When a lung cancer patient is complicated with hypercalcemia, we need to consider that primary hyperparathyroidism is a possible cause of the hypercalcemia. 相似文献
5.
Changes in central dopaminergic systems with the expression of Shh or GDNF in mice perinatally exposed to bisphenol-A. 总被引:1,自引:0,他引:1
Kazuya Miyagawa Minoru Narita Michiko Narita Keiichi Niikura Hisahiko Akama Yuri Tsurukawa Tsutomu Suzuki 《Nihon shinkei seishin yakurigaku zasshi》2007,27(2):69-75
In the previous study, we reported that exposure to bisphenol-A induced the potentiation of dopamine receptor functions in the mouse limbic area, resulting in supersensitivity to methamphetamine-induced pharmacological actions. The present study was undertaken to investigate whether prenatal exposure to bisphenol-A could produce morphological change in dopaminergic neuron and the pattern of expression of genes regulating the dopaminergic neuron development. Here we found that prenatal and neonatal exposures to bisphenol-A increased the tyrosine hydroxylase- and dopamine transporter-like immunoreactivities in the adult mouse limbic area. The present molecular biological study shows that chronic bisphenol-A treatment produced a significant decrease in the dopaminergic neuron development factors, sonic hedgehog and glial cell line-derived neurotrophic factor, which were also decreased by prenatal exposure to bisphenol-A. These results suggest that chronic exposure to bisphenol-A could disrupt the dopaminergic neurotransmission in the process of dopaminergic neuron development. 相似文献
6.
7.
Kiyohito Yamamoto Koji Onoda Yasuhiro Sawada Kazuya Fujinaga Kyoko Imanaka-Yoshida Toshimichi Yoshida Hideto Shimpo 《Annals of thoracic and cardiovascular surgery》2007,13(5):322-330
BACKGROUND: Pathological changes in vein grafts begin immediately after arterial circulation is applied to the grafts. Chemical mediator stimulation and mechanical strain induce neointimal hyperplasia and medial thickening of the vein grafts, resulting in their failure. We investigated the inhibitory effect of locally applied cilostazol, an inhibitor of cyclic adenosine monophosphate phosphodiesterase III, on neointimal hyperplasia and medial thickening of the grafts. METHODS AND RESULTS: We established a distal anastomotic stricture model of femoral vein-abdominal aorta interposition grafting in rats. In this model, neointimal hyperplasia was observed not only at the distal anastomotic sites, but also in the graft body at postoperative day 14 and was markedly progressed at day 28. A strong expression of tenascin-C was found in the media and neointima of the graft body. In the grafts around which cilostazol was administered locally using Pluronic gel, neointimal hyperplasia was significantly suppressed compared with control grafts treated with the gel alone, with the mean neointimal cross-sectional area reduced by 87.1% for the graft body and by 78.9% for the distal anastomotic sites and mean medial cross-sectional area of the graft body reduced by 54.2% at day 28 versus the control. Cilostazol treatment decreased cell proliferation and the number of tenascin-C-producing cells seen by in situ hybridization, but the expression of tenascin-C protein was not suppressed. CONCLUSION: We concluded that a single perivascular application of cilostazol inhibits neointimal hyperplasia and medial thickening of vein grafts in a rat model. 相似文献
8.
Kohjirou Okahashi Kazuya Sugimoto Makoto Iwai Manabu Oshima Masayuki Samma Yoshiyuki Fujisawa Yoshinori Takakura 《Knee surgery, sports traumatology, arthroscopy》2006,14(6):542-545
The purpose of our study is to evaluate whether the hamstring tendons can regrow after harvesting for anterior cruciate ligament (ACL) reconstruction and whether the regenerate tissue can be histologically characterized as tendinous. Eleven of the patients (eight female and three male; mean age, 23 years; range 17–37 years) consented to participate in this study. One year after the ACL reconstruction, surgical biopsy was done. Regeneration of the tendon was detected macroscopically in 9 of the 11 patients. Histologically and immunohistochemically, the regenerated tendons closely resembled normal ones. The results of this study show the hamstring tendons can regenerate after harvesting for the ACL reconstruction. 相似文献
9.
I. Tsunoda Yuzo Iwasaki Hiroshi Terunuma Kazuya Sako Yoshiro Ohara 《Acta neuropathologica》1996,91(6):595-602
Theiler’s murine encephalomyelitis viruses (TMEV) are divided into two subgroups on the basis of their different biological
activities. The GDVII strain produces acute polioencephalomyelitis in mice, whereas the DA strain produces demyelination with
virus persistence in the spinal cord. A comparative study of GDVII and DA strains suggested that low host immune responses
are responsible for the development of acute GDVII infection and that the persistence of infected macrophages plays a crucial
role in the development of chronic white matter lesions in DA infection. All 78 mice infected with GDVII died or became moribund
by day 13, while none of 54 mice infected with DA died. In the acute stage, the distribution of viral antigens in the central
nervous system (CNS) tissue was similar in both GDVII and DA infections, although the virus titer was higher in GDVII infection.
In DA infection, a substantial number of T cells were recruited to the CNS on day 6 when they were virtually absent in GDVII
infection. The titer of neutralizing antibody was already high on day 6 in DA infection but was negligible in GDVII infection.
Development of chronic paralytic disease from day 35 of the DA infection was accompanied by focal accumulation of viral antigen-positive
macrophages in the spinal white matter. In addition, white matter lesions comparable to those in chronic DA infection were
induced in the spinal cord within 7 days after intracerebral injection of DA-infected murine macrophages.
Received: 26 June 1995 / Revised, accepted: 27 December 1995 相似文献
10.
K Sugino Y Kure R Shiraishi H Iwasaki H Sato Y Kumamoto A Matsumoto 《Nihon Geka Gakkai zasshi》1990,91(8):923-930
Recently, mean span of life has been prolonged, and extensive operations are performed on aged patients. However, there are cases which have a difference between their chronological and actual ages. Bone mineral content (BMC) decreases with age and the decrease in BMC might suggest deterioration of immunological competence as observed in osteoporosis. Whether BMC can be an index for evaluation of geriatric patients' actual age from the aspect of immunological competence was investigated. Subjects were 54 cases aged more than 60. Twenty-one healthy young males and females were enrolled as the control group. Quantitative CT is used for assessment of BMC. The value obtained by dividing BMC by the standard BMC of the same age and sex, was defined as BMC index. BMC indices of normal BMC group were more than 0.8 and those of decreased BMC group were less than 0.8. Some immunological markers were investigated. Lymphocyte subset OKT3+ was reduced and juvenile lymphocytes expressed by OKT6+ and OKT3+-(OKT4+ + OKT8+) increased (corrected). Increased in juvenile lymphocyte and decrease in lymphocyte blast transformation and competence of generating interleukin 2 were observed in decreased BMC group. BMC is useful as preoperative evaluation for geriatric operative cases and patients of BMC index below 0.8 need to be paid attention to postoperative infection. 相似文献