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991.
992.
993.
Trimethylaminuria is caused by mutations of the FMO3 gene in a North American cohort. 总被引:1,自引:0,他引:1
B R Akerman H Lemass L M Chow D M Lambert C Greenberg C Bibeau O A Mamer E P Treacy 《Molecular genetics and metabolism》1999,68(1):24-31
Trimethylaminuria (TMAuria) (McKusick 602079) first described in 1970 is an autosomal recessive condition caused by a partial or total incapacity to catalyze the N-oxygenation of the odorous compound trimethylamine (TMA). The result is a severe body odor and associated psychosocial conditions. This inborn error of metabolism, previously thought to be rare, is now being increasingly detected in severe and milder presentations. Mutations of a phase 1 detoxicating gene, flavin-containing monooxygenase 3 (FMO3), have been shown to cause TMAuria. Herein we describe a cohort of individuals ascertained in North America with severe TMAuria, defined by a reduction of TMA oxidation below 50% of normal with genotype-phenotype correlations. We detected four new FMO3 mutations; two were missense (A52T and R387L), one was nonsense (E314X). The fourth allele is apparently composed of two relatively common polymorphisms (K158-G308) found in the general population. On the basis of this study we conclude that one common mutation and an increasing number of private mutations in individuals of different ethnic origins cause TMAuria in this cohort. 相似文献
994.
B. D. Greenberg Jonathan Benjamin Juliet D. Martin David Keuler S.-J. Huang Margaret Altemus Dennis L. Murphy 《Psychopharmacology》1998,140(4):434-444
Enhanced serotonergic transmission may underlie therapeutic effects of serotonin reuptake inhibitors in obsessive-compulsive
disorder. However, such treatment may decrease serotonin receptor responsivity. We investigated whether the serotonin antagonist
metergoline would exacerbate or further improve systems in fluoxetine-responsive patients. Pilot results suggested open metergoline
produced delayed symptom worsening in fluoxetine-treated patients. Fourteen patients continuing fluoxetine received metergoline
and placebo (double-blind, randomized). Symptom ratings continued for 1 week afterwards. Ten unmedicated patients underwent
the same procedures. Symptoms improved 4 h after both metergoline and placebo. The day after metergoline but not placebo,
fluoxetine-treated patients had significantly increased anxiety, obsessions and compulsions, abating over several days. Depression
was unchanged. Metergoline had no similar delayed effects in unmedicated patients. Metergoline levels were higher in fluoxetine-treated
patients. These results, consistent with less conclusive earlier findings, suggest that prolonged changes in brain serotonin
function underlie symptom re-emergence following administration of metergoline to fluoxetine-treated patients with obsessive-compulsive
disorder.
Received: 24 November 1997/Final version: 21 April 1998 相似文献
995.
LuAnn Klemme Alfred J. Fish Stephen Rich Beryl Greenberg Beverly Senske Miriam Segall 《Pediatric nephrology (Berlin, Germany)》1998,12(5):349-356
Abnormal development of the ureter during embryogenesis, when occurring in multiple family members, appears to be a genetically
determined defect with autosomal dominant inheritance and high penetrance, which can lead to significant kidney damage, renal
failure, and death. We have studied 48 individuals within a large kindred in which ureteral-related abnormalities (including
vesicoureteral reflux, ureteropelvic junction obstruction, duplicated ureters, and medullary sponge kidney) were segregated.
Family members who had not had previous diagnostic studies were evaluated for presence or absence of ureteral abnormalities
and we attempted to map the locus for this familial ureteral abnormalities syndrome (FUAS). These studies identified 11 asymptomatic
individuals, previously assumed to be unaffected, with minor abnormalities. When linkage analysis between the inheritance
of ureteral abnormalities and six marker loci glyoxalase I (GLO-1), major histocompatibility antigens (HLA-A, B, and DR/DQ),
D6S288, and factor XIII antigen (F13A1) on the short arm of chromosome 6 was performed, the lod scores significantly rejected
linkage over a 77.1-cM distance. These findings are in contrast to previous data suggesting linkage between the presence of
ureteral abnormalities and HLA, and indicate the possibility of genetic heterogeneity of FUAS.
Received April 29, 1997; received in revised form September 15, 1997; accepted September 22, 1997 相似文献
996.
The genes encoding effector molecules of mature T cells, IL-2, perforin and
IL-4, were found to be expressed in vivo in the most primitive subsets of
thymocytes of adult mice. These subsets have previously been identified by
their cell surface markers and by their expression of other T
lineage-associated genes. While IL-2, perforin and IL-4 are expressed in
distinct patterns, all three are expressed before the induction of RAG-1
and pre-TCR alpha mRNA expression, and are confined to subsets of cells
that apparently have not yet undergone commitment to the T lineage. Thus,
expression of T cell response genes appears to be one of the earliest
markers of lymphocyte differentiation. Activation events marked by CD69
induction occur in these early cell types, but the response gene expression
by these cells is separable from CD69 expression. IL-2 and perforin are
induced again much later in thymocyte development, during TCR-dependent
repertoire selection. At those stages, IL-2 protein and RNA levels per cell
are higher, but the fraction of cells expressing IL-2 appears to be much
lower than in the most immature stages. In addition, a striking feature of
the immature populations is the robust IL-2 expression by presumptive
immature NK cells. These findings are discussed in terms of the
developmental origins of lineage specificity in T cell response gene
regulation.
相似文献
997.
We evaluated the effects of recombinant human granulocyte colony stimulating factor (rhG-CSF) and granulocyte-monocyte colony stimulating factor (rhGM-CSF) on the in vitro proliferative, differentiative, and regenerative responsiveness of marrow cells from myelodysplastic syndrome patients (MDS) in comparison to those from normal individuals. Our studies showed decreased primary clonogenicity of myeloid (CFU-GM) and erythroid (BFU-E) hemopoietic progenitor cells from the MDS patients. rhGM-CSF had more potent stimulatory effects than rhG-CSF for MDS marrow CFU-GM growth; no enhanced cellular proliferation in the MDS patients was observed in liquid culture with either rhGM-CSF or rhG-CSF. Decreased myeloid clonal cell self-generation and/or recruitment occurred in the MDS patients upon exposure to either rhG-CSF or rhGM-CSF. rhG-CSF demonstrated more potent granulocytic differentiation effects than rhGM-CSF both for normals and MDS patients using marrow enriched for immature myeloid cells with lesser differentiation noted for MDS. Cytogenetic abnormalities, present with or without additional normal karyotypes in native marrow of four MDS patients, persisted after culture with rhG-CSF, indicating induced differentiation of both normal and abnormal clones. Although proliferative and differentiative effects were seen with both factors these data show MDS marrow cells in vitro to have predominantly differentiative responsiveness to rhG-CSF and proliferative responsiveness to rhGM-CSF. 相似文献
998.
J P LaPolla W S Roberts H Greenberg J J Kavanagh S F Quinn M Hoffman J Fiorica D Cavanagh 《Gynecologic oncology》1990,37(1):55-59
The results of a pilot study employing the administration of intraarterial chemotherapy and accelerated fractionation radiotherapy for advanced gynecologic malignancies are reported. The protocol consisted of three treatment sessions every 3 to 4 weeks. Each session consisted of bilateral or unilateral catheterization of the hypogastric artery with the infusion of cisplatin 100 mg/m2 on Day 1 and 2-deoxy-5-fluorouridine (FUDR) 300 mg/m2 on Day 2. An accelerated fractionation schedule of external-beam radiation was begun on Day 1 consisting of 200 rads twice daily for 4 days (1600 rads per session). Eight patients entered the protocol, and seven completed external-beam radiotherapy. Five completed three intraarterial sessions, and three, two sessions. Five of seven evaluable patients had a complete local response. Local control was sustained fom 6 to 24 months in four patients. Complications included three sensorimotor neuropathies, one clinically insignificant catheter-related thrombosis, and three clinically significant radiation injuries. This multimodality treatment for locally advanced gynecologic tumors appears feasible with modification, and continued work exploring this approach is encouraged. 相似文献
999.
Positive control of a global antioxidant defense regulon activated by superoxide-generating agents in Escherichia coli. 总被引:59,自引:5,他引:54 下载免费PDF全文
1000.
H B Muss C P Hunter M Wesley P Correa V W Chen R S Greenberg J W Eley D F Austin R Kurman B K Edwards 《Cancer》1992,70(10):2460-2467
BACKGROUND. The National Cancer Institute Black/White Cancer Survival Study began patient accrual in 1985 and was designed to investigate factors that might contribute to the observed racial differences in survival for cancer of the breast, uterine corpus, colon, and bladder. METHODS. To determine whether there were racial differences in treatment in a clinically homogeneous set of patients, 305 (25%) of the 1222 women in this study with Stage II node-positive (N+) breast cancer were evaluated. RESULTS. Patient characteristics for blacks and whites were similar for age, metropolitan area of residence, tumor size, extent of nodal involvement, and steroid receptors. Differences in histologic findings, tumor grade, and nuclear atypia were observed. Blacks had a higher frequency of comorbid conditions, especially hypertension (P < 0.00001). Fewer blacks underwent breast-conserving surgery (P = 0.004). In a multivariate analysis, race was no longer a significant factor in the selection of primary treatment, but education and metropolitan area of residence remained significant. Blacks and whites received similar postoperative systemic therapy, with combination chemotherapy (cyclophosphamide, methotrexate, and 5-fluorouracil) and tamoxifen, the most common cytotoxic and endocrine therapies used. CONCLUSIONS. The National Cancer Institute consensus statement concerning adjuvant therapy for breast cancer was published in the middle of the 2-year period that study cases were accrued, and treatment plans in this study generally agreed with consensus guidelines. Should survival differences in black and white patients with Stage II N+ disease in this study be found, they are unlikely to be attributable to differences in initial or postoperative treatment. 相似文献