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排序方式: 共有1079条查询结果,搜索用时 15 毫秒
1.
Detection of the carrier state of X-linked retinoschisis   总被引:8,自引:0,他引:8  
We determined the extent of suppressive rod-cone interaction in 11 obligate carriers and eight potential carriers of X-linked retinoschisis from eight families. Despite otherwise normal ophthalmoscopic and functional testing, all of the obligate heterozygous carriers demonstrated a complete absence of normal rod-cone interaction. Of the potential heterozygous carriers, three had normal rod-cone interactions, two had no detectable interaction, and two yielded technically unsatisfactory results. This lack of rod-cone interactions allows heterozygous individuals to be identified clinically and has implications concerning the origin of this inherited disorder.  相似文献   
2.
E Erturk  E Erturk  J Sheinfeld  R S Davis 《Urology》1988,32(2):165-167
It is well documented that under certain stimuli the bladder epithelium can undergo metaplasia. The origin of glandular epithelium, which may be found in the bladder, is somewhat controversial. Endoscopic and histopathologic features of an eighty-one-year-old white man with proliferative metaplastic cystitis are presented. This case demonstrates that glandular differentiation was due to progressive cystitis rather than congenital intestinal rest.  相似文献   
3.
E Erturk  J Sheinfeld  R S Davis 《Urology》1987,30(3):284-286
After years of decline to near disappearance, there recently has been an increasing incidence of syphilis in America. New cases of tertiary neurosyphilis are being reported which often have associated significant urologic sequelae. For the first time in the English literature, the uro-dynamic findings of a patient with tabes dorsalis are presented. Our findings indicate that treatment of urinary retention associated with tabes dorsalis is better managed by intermittent catheterization than by prostate surgery because of the impaired detrusor activity. A review of neurosyphilis and its urologic implications and urodynamic findings are presented. Prompt recognition of this entity should encourage a full urodynamic evaluation prior to a commitment to prostatic surgery.  相似文献   
4.
Twenty patients with advanced malignant disease submitted to autologous bone marrow transplantation with marrow either unpurged (10 patients) or purged in vitro with mafosfamide (10 patients) after ablative chemotherapy, received simultaneously autologous peripheral blood stem cells (PBSC) collected during one to three 3 h cytapheresis procedures. The kinetics of the hematological recovery of these patients were compared to those of a group of patients suffering from similar diseases and grafted in the same institution with either unpurged marrow only (14 patients) or purged in vitro with mafosfamide (six patients). The median times to reach 10(9)/l leukocytes, 0.5 x 10(9)/l polymorphs, and 50 x 10(9)/l platelets were reduced by 10, 10, and 13 days, respectively, in patients transfused with both autologous bone marrow and peripheral blood stem cells as compared to those receiving bone marrow only. A reduction in the numbers of days spent in hospital post-transplantation (p less than 0.01), of days of fever greater than 38 degrees C (p = NS), and of platelet (p = 0.07) and of red blood cell transfusions (p less than 0.01) were also observed in the group of patients grafted with bone marrow and PBSC.  相似文献   
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6.
The effect of solubilization of deoxyribonucleoproteins (DNP) in a medium of near-physiological ionic strength after treatment with the mutagen N-nitroso-N-methylurea (NMU) is highly dependent on the NMU concentration. To convert DNP into a soluble state, the critical number of groups in the DNA and protein must evidently be modified. On the basis of data obtained by the circular dichroism method and by viscosimetry it is concluded that after treatment with NMU the DNP complex becomes soluble in solvents with near-physiological ionic strength largely as a result of labilization and dissociation of the DNA-protein bonds.Laboratory of Biophysics, Institute of Medical Genetics, Academy of Medical Sciences of the USSR. Sector of Kinetics of Chemical and Biological Processes, Institute of Chemical Physics, Academy of Sciences of the USSR. Laboratory of Physical Methods of Investigation, D. I. Ivanovskii Institute of Virology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR S. S Debov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 6, pp. 674–677, June, 1976.  相似文献   
7.
Genetic heterogeneity of Usher syndrome type II.   总被引:2,自引:3,他引:2       下载免费PDF全文
Usher syndrome is an autosomal recessive disorder characterised by retinitis pigmentosa and congenital sensorineural hearing loss. A gene for Usher syndrome type II (USH2) has been localised to chromosome 1q32-q41. DNA from a family with four of seven sibs affected with clinical characteristics of Usher syndrome type II was genotyped using markers spanning the 1q32-1q41 region. These included D1S70 and D1S81, which are believed to flank USH2. Genotypic results and subsequent linkage analysis indicated non-linkage of this family to these markers. The A test analysis for heterogeneity with this family and 32 other Usher type II families was statistically significant at p < 0.05. Further clinical evaluation of this family was done in light of the linkage results to determine if any phenotypic characteristics would allow for clinical identification of the unlinked type. No clear phenotypic differences were observed; however, this unlinked family may represent a previously unreported subtype of Usher type II characterised by a milder form of retinitis pigmentosa and mild vestibular abnormalities. Heterogeneity of Usher syndrome type II complicates efforts to isolate and clone Usher syndrome genes using linkage analysis and limits the use of DNA markers in early detection of Usher type II.  相似文献   
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9.
Human autoimmune thyroid cells "spontaneously" express MHC-class II antigens. These antigens have been assumed to trigger thyroid-specific helper T cell clones, leading in turn to the expansion of thyroid autoantibody-secreting B cells. Thyroid cells derived from non-autoimmune subjects do not express MHC-class antigens, but these can be readily induced with gamma-interferon. We have addressed the issue of whether it is sufficient for normal thyroid cells to bear class II antigens in order to trigger autologous T cells. We found that non-autoimmune thyrocytes expressing DR antigens fail to stimulate autologous resting T cells. However, proliferative activity and interleukin-2 secretion were observed when fresh T cells were first triggered by autologous non-T cells and then incubated with thyrocytes. More CD8 than CD4 cells proliferated in the T:thyrocyte cultures, but CD4 cells were necessary for the proliferation and interleukin-2 secretion. Addition of antibodies to thyroglobulin or to DR antigens inhibited T cell proliferation and interleukin-2 secretion, thus pointing to T cell recognition of both thyroid-specific and DR antigens. Evaluation of the function of the thyroid stimulated T cells revealed very potent suppressor but negligible helper and cytotoxic activities. It would seem, therefore, that DR-restricted T cell activation by autologous antigen on non-autoimmune thyroid cells does occur, but since it results in enhanced suppression, its nature seems protective, thus leading to maintenance of immunological self-tolerance.  相似文献   
10.
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