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排序方式: 共有2365条查询结果,搜索用时 31 毫秒
961.
A recently developed chemically defined diet containing crystalline amino acids (16% of the diet, 14.4% crude protein equivalent) as the sole source of nitrogen was compared to a methionine-fortified case in diet (20% crude protein) when fed in dry form to weanling rats and mice. Rate and efficiency of weight gain were similar for both diets in rats as well as mice. This finding suggests that the crystalline amino acid diet results in near maximal growth performance and thus supports its efficacy in future nutrition research endeavors. 相似文献
962.
963.
964.
Clinicopathologic study of squamous cell carcinoma of the ovary 总被引:1,自引:0,他引:1
Clinicopathologic study was performed on 10 squamous cell carcinomas of the ovary. All four patients with stage II or III lesions had deteriorated within 1 year after the operation, and four of six patients with stage I lesions had survived over 5 years. Clinical findings of the patients with ovarian SCC, including age, chief complaint, clinical stage, and outcome of the patients, were similar to those of common epithelial cancer. The effectiveness of chemotherapy was not shown in this study. Histopathologic study revealed that squamous cell carcinoma may arise not only from epidermis, but also from squamous metaplastic epithelium of respiratory gland. 相似文献
965.
S Yokoyama H Hirakawa T Tajima T Mitomi H Yabe M Yabe S Kato 《Nihon Geka Gakkai zasshi》1991,92(9):1147-1150
Bone marrow transplantation permits the use of greatly intensified cytoreductive therapy for cancer. Since 1981, fifteen children with disseminated solid tumor were treated by this method (6 Nb1, 6 Lymphoma, 1 PNET, 1 Hb1, 1 YST.). Eight out of 15 (53%) have been alive and well 2-96 (median 45) months after BMT. Though toxicity is severe, high dose chemo-radiotherapy using BMT after reaching complete remission with well scheduled induction chemotherapy and surgery is concluded as a treatment of choice for pediatric malignant solid tumor in advanced stage. 相似文献
966.
H Hirakawa T Mtsueda T Iida K Fukamachi K Takahashi J Nagayama T Nagata 《Fukuoka igaku zasshi》1991,82(5):274-279
3,4,3',4'-tetrachlorobiphenyl (T4CB), 3,4,5,3',4'-pentachlorobiphenyl (P5CB) and 3,4,5,3',4',5'-hexachlorobiphenyl (H6CB) [Co-PCBs] in the subcutaneous adipose tissue of seven Yusho patients and eight normal controls were determined to assess the contribution in the risk caused by the Yusho causual agents (PCBs, PCDFs, PCDDs and Co-PCBs) by using high resolution gas chromatography/high resolution mass spectrometry in selected ion monitoring mode. 3,4,3',4'-T4CB, 3,4,5,3',4'-P5CB and 3,4,5,3',4',5'-H6CB were detected in the subcutaneous adipose tissue of the Yusho patients at the levels, of 6 to 29 ppt, of 32 to 130 ppt and of 160 to 1,140 ppt, respectively. The TCDD-Eq (Equivalents) value calculated by TCDD-TEfs (Toxic Equivalent factors) was from 8 to 30 ppt. On the other hand, 3,4,3',4'-T4CB, 3,4,5,3',4'-P5CB and 3,4,5,3',4',5'-H6CB were detected in the subcutaneous adipose tissue of normal controls at the levels, of 3 to 9 ppt, of 41 to 280 ppt and of 47 to 200 ppt, respectively. The TCDD-Eq value calculated by TCDD-TEfs was from 9 to 57 ppt. In the Yusho patients, the average TCDD-Eq value calculated by TCDD-TEfs of the residual Co-PCBs, PCDFs and PCDDs was 17, 491 and 24 ppt, respectively. Therefore, we concluded that the typical symptoms for the Yusho patients are caused mostly by PCDFs. 相似文献
967.
Yoshiyuki Nakashima Takanobu Nii Eiichiro Tashiro Masaharu Ikeda Kikuo Arakawa 《Clinical and experimental pharmacology & physiology》1992,19(6):425-431
1. The direct cardiac effects of angiotensin-converting enzyme (ACE) inhibitor in 22 hypertensive patients were investigated. Radionuclide ventriculography and echocardiography were performed to measure left ventricular function before and 60 min after administration of a subdepressor dose of captopril. 2. Since the response to ACE inhibitor is not uniform, patients were classified into 12 patients without significant blood pressure change following captopril (group I) and 10 patients with reduction of blood pressure (group II). 3. Clinical and baseline haemodynamic characteristics were similar for the two groups. 4. Ejection fraction (EF) increased without changes of heart rate and end-diastolic dimension after ACE inhibitor in group I as well as group II. The change of EF was not different for the two groups. No correlation was found between changes in EF and blood pressure in group I patients. 5. This study indicates that ACE inhibitor might directly influence left ventricular function independent of systemic haemodynamic changes. 相似文献
968.
969.
Summary Growth analysis of medulloblastomas was performed in two children. They initially manifested symptoms at the age of 3 years and 9 months and at the age of 2 months respectively. Computerized tomography (CT) scans were obtained at different points in each case. The growth curves were drawn on a semilogarithmic graph by calculating the tumor volume on CT on the assumptions that the tumor started from a single tumor cell and that the growth rate was constant. By extrapolating the curves back, tumor inception was estimated to have occurred respectively at the 14–23rd week and at the 16–17th week of gestation. Additional cell kinetic data were obtained from DNA analysis of surgical pathology specimens. Calculated cell-cycle times were 22–32 h for both cases. The S phases comprised 26.3% and 27% and the G0G1 phases 66.8% and 62% of the cell cycle, respectively, for case 1 and 2. Assuming a labelling index of 14%, the cell loss factors were estimated to be 97% and 74% (case 1 and case 2 respectively). The seventeenth week of gestation in humans corresponds to the timing of events occurring postnatally at days 3–18 in the developing cerebella of rodents, i.e., at the time of maximal activity in the migration and differentiation of the cells of the fetal external granular layer. Medulloblastomas have been experimentally induced in rodents by the injection of oncogenic viruses during the neonatal period, and statistical data on the epidemiology of human medulloblastomas have suggested a possible association with the contamination of polio vaccine by the SV 40 virus. Therefore, it seems reasonable to assume that these medulloblastomas originated in the cerebellum during the period of active development of the cerebellum. 相似文献
970.
Time-related changes in the distribution of chemical messengers in the rat spinal cord following the transection of dorsal and ventral roots were observed by using immunohistochemistry for the following antigens: microtubule-associated protein 2 (MAP2), calcitonin gene-related peptide (CGRP), substance P (SP), galanin (Gal), Met-enkephalin (Enk), neuropeptide Y (NPY), and serotonin (5-HT). To investigate dendrocytoarchitectonic organizational changes, morphometric analyses were performed on both the gray and the white matter of tissue samples stained with MAP2 antiserum. A significant reduction in the area of gray matter on the lesioned side was seen from 1 to 24 weeks postoperation, and progressive changes in the shape of the gray matter were also observed. CGRP-immunoreactive fibers were reduced in number in the posterior horn after root transection, except in the lateral part of lamina I. In contrast, CGRP immunoreactivity in the anterior horn cells of the ipsilateral side was increased early after transection, but later it progressively decreased. Root transection also caused significant reduction in the number of SP-immunoreactive fibers in the posterior horn, but no changes were seen in the anterior horn. Gal immunoreactivity was also affected by root transection, and it changed in a similar way to CGRP immunoreactivity. 5-HT-immunoreactive fibers were increased in the posterior horn after transection, and later decreased. In the anterior horn, there were no changes in the intensity or distribution pattern of 5-HT-immunoreactive nerve fibers following root transection. Enk and NPY immunoreactivity in the anterior and posterior horns was not affected by root transection up to 24 weeks postoperative. These results show that spinal root transection caused significant changes in the chemoarchitectural organization of nerve fibers containing certain types of chemical messengers, such as CGRP, SP, Gal, and 5-HT, in addition to altering dendritic geometry in the spinal cord. 相似文献