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81.
Tissue and lineage-specific variation in inactive X chromosome expression of the murine Smcx gene 总被引:2,自引:0,他引:2
To understand how gene expression patterns are established on the inactive
X chromosome during development, we have studied the murine gene Smcx,
which is expressed from both the active and inactive mouse X chromosomes.
In all tissues assayed, Smcx only partially escapes X inactivation, with
expression levels from the inactive X allele approximately 30-65% that of
the active X allele. Additionally, inactive X expression levels differed
between extraembryonic and embryonic tissues and among different tissues
from newborn and adult mice. Imprinted extraembryonic tissue had the lowest
levels of inactive X Smcx expression, whereas the highest levels were in
heart. These data suggest that the chromosomal basis of X inactivation
differs among tissues, perhaps reflecting differences in the timing or
regulation of inactivation in these cell lineages.
相似文献
82.
A group of girls is described with recurrent urinary tract infections characterized by predominantly lower tract symptoms. Clinical, laboratory, and radiography findings during the period of follow-up are presented. Infection persisted in most patients over several years. Response to medical and surgical treatment was unsatisfactory. The mean interval between the initial and most recent radiological study was 6 1/2 years. No case of renal parenchymal scarring was seen. 相似文献
83.
A model of corrective gene transfer in X-linked ichthyosis 总被引:5,自引:0,他引:5
Freiberg RA; Choate KA; Deng H; Alperin ES; Shapiro LJ; Khavari PA 《Human molecular genetics》1997,6(6):927-933
Single gene recessive genetic skin disorders offer attractive prototypes
for the development of therapeutic cutaneous gene delivery. We have
utilized X-linked ichthyosis (XLI), characterized by loss of function of
the steroid sulfatase arylsulfatase C (STS), to develop a model of
corrective gene delivery to human skin in vivo. A new retroviral expression
vector was produced and utilized to effect STS gene transfer to primary
keratinocytes from XLI patients. Transduction was associated with
restoration of full-length STS protein expression as well as steroid
sulfatase enzymatic activity in proportion to the number of proviral
integrations in XLI cells. Transduced and uncorrected XLI keratinocytes,
along with normal controls, were then grafted onto immunodeficient mice to
regenerate full thickness human epidermis. Unmodified XLI keratinocytes
regenerated a hyperkeratotic epidermis lacking STS expression with
defective skin barrier function, effectively recapitulating the human
disease in vivo. Transduced XLI keratinocytes from the same patients,
however, regenerated epidermis histologically indistinguishable from that
formed by keratinocytes from patients with normal skin. Transduced XLI
epidermis demonstrated STS expression in vivo by immunostaining as well as
a normalization of histologic appearance at 5 weeks post-grafting. In
addition, transduced XLI epidermis demonstrated a return of barrier
function parameters to normal. These findings demonstrate corrective gene
delivery in human XLI patient skin tissue at both molecular and functional
levels and provide a model of human cutaneous gene therapy.
相似文献
84.
We report the successful long-term engraftment of normal male donor bone marrow (BM) transfused into noncytoablated female mice, challenging the assumption that "niches" need to be created for marrow to engraft. We have used chromosomal banding and Southern blot analysis to identify transplanted male marrow cells, and shown the long-term stability of the chimeric marrows. Balb/C, BDF1, or CBA-J female hosts (no irradiation) received for 5 consecutive days 40 x 10(6) male cells (per day) of the same strain, and repopulation patterns were observed. Parallel studies were performed using tibia/femur equivalents of normal marrow or marrow from Balb/C mice pretreated 6 days previously with 150 mg/kg 5-fluorouracil (5-FU). Chromosome banding techniques showed that 5% to 46% of marrow cells were male 3 to 9 months posttransplant with normal donor marrow. Southern blot analysis, using the pY2 probe, showed continued engraftment at 21 to 25 months posttransplant, ranging from 15% to 42% male engrafted cells in marrow. Normal donor male marrow engrafted significantly better than 5-FU-pretreated male marrow as shown 1 to 12 months posttransplant in non-cytoablated female recipients. Percentages of male engrafted cells in BM ranged from 23% to 78% for recipients of normal donor marrow and from 0.1% to 39% for recipients of 5-FU marrow. Mean engraftment for 6 mice receiving normal marrow was 38%, whereas that for 6 mice receiving post-5-FU marrow was 8%, as assayed 1 to 3 months posttransplant. At 10 to 12 months, mean engraftment for the normal donor group was 46%, compared with 16% for the 5-FU group. The patterns of engraftment with normal and 5-FU marrow were similar for spleen and thymus. These results show that long-term chimerism can be established after transplantation of normal donor marrow to normal nonirradiated host mice and indicate that marrow spaces do not have to be created for successful engraftment. They suggest that transplanted marrow competes equally with host marrow for marrow space. Finally, these data show that post-5-FU Balb/C male marrow is markedly inferior in the repopulation of Balb/C female host marrow, spleen, and thymus, and suggest that this population of cells may not be the ideal population for gene transfer studies. 相似文献
85.
Arthrograms of the temporomandibular joint were obtained in 20 symptomatic joints that had previous reconstructive arthroplasty with disk repositioning because of internal derangements. Preoperative arthrograms were available for comparison in 18 joints. Symptoms resulting in a postoperative arthrogram included pain, limited ability to open the mouth, and clicking of the joints. Postoperative arthrographic findings included limited anterior translation of the condyle (90%), irregularity in outline of the intraarticular contrast agent (60%), a conical configuration of the posterior recess (25%), decreased size of the joint (28%), anterior displacement of the meniscus (25%), and perforated meniscus (15%). Many of these findings may have resulted from fibrosis and scarring, which may be a response to intraarticular bleeding. The mechanism by which the fibrosis causes the postsurgical arthrographic features is discussed. 相似文献
86.
大孔树脂吸附法富集野菊花总黄酮的工艺研究 总被引:11,自引:0,他引:11
目的研究大孔树脂吸附法富集野菊花总黄酮的工艺条件及参数。方法以野菊花总黄酮为考察指标,考察大孔树脂富集野菊花总黄酮的最佳工艺条件。结果野菊花提取液(50mg生药/mL)5mL上大孔树脂柱(150mm×10mm),吸附30min后,先用100mL蒸馏水洗脱除去杂质,然后用70%乙醇100mL洗脱,洗脱速度为2mg/mL,洗脱剂用量为9倍量树脂,树脂可重复使用3次,采用此条件为最佳工艺。结论AB-8型大孔树脂在所确定的工艺条件下,可较好的吸附分离野菊花总黄酮。其70%乙醇洗脱物中总黄酮质量分数达4.34%以上,总黄酮收率为84.47%以上。采用此法可以较好的富集野菊花中的有效成分。 相似文献
87.
Blood loss and replacement in total hip arthroplasty: a multicenter study. The Preoperative Autologous Blood Donation Study Group 总被引:1,自引:0,他引:1
To determine blood loss, the number of transfusions, and the hemoglobin levels achieved in patients via transfusion in the course of total hip arthroplasty, 324 patient records from 1987 through 1989 were reviewed at three university and three community hospitals. Calculated blood loss was 3.2 +/- 1.3 units in primary procedures and 4.0 +/- 2.1 units in revision procedures (mean +/- SD). Of 777 red cell units transfused, 455 (59%) were autologous units. Transfused patients received 2.0 +/- 1.8 units for primary procedures and 2.9 +/- 2.3 units for revision procedures (mean +/- SD). The maximum number of units given to 95 percent of the transfused patients was 4 for primary procedures and 6 for revision procedures. The mean postoperative hemoglobin level after all transfusions was 103 to 110 g per L, regardless of patient age group of physical status, autologous donor status, or hospital. No difference in length of hospital stay was observed for patients less than 65 years old with hemoglobin concentrations of 80 to 139 g per L at discharge. 相似文献
88.
89.
目的:急性冠状动脉综合征(ACS)置入支架患者使用盐酸替罗非班、阿司匹林、氯吡格雷、低分子肝素(四联)时,评价泮托拉唑对消化道的保护作用.方法:选择ACS置入支架治疗的患者266例,随机分入观察组134例,对照组132例,所有患者均服用阿司匹林、氯吡格雷、低分子肝素和盐酸替罗非班.观察组患者静脉注射泮托拉唑40 mg/d 4~5天,之后改为泮托拉唑片剂40 mg/次,2次/天,服用30天.观察两组间30天全因死亡、再次心肌梗死、再次经皮冠状动脉介入治疗(PCI)、再次住院、颅内出血和消化道出血状况.结果:观察组134例患者30天内全因死亡5例、再次心肌梗死4例、再次PCI4例和再次住院8例;对照组132例患者分别为8例、6例、5例和13例,两组相比差异均无统计学意义(P>0.05);两组均无颅内出血发生.观察组消化道大出血0和总消化道出血事件3例,对照组分别为5例和15例,两组比较观察组消化道大出血和总消化道出血事件少于对照组(P<0.05),差异均有统计学意义.结论:ACS置入支架治疗的患者,盐酸替罗非班治疗是安全有效的,未见颅内出血发生.静脉注射和口服泮托拉唑并不增加30天全因死亡、再次心肌梗死、再次PCI和再次住院发生,同时可以减少30天内消化道出血发生率特别是消化道大出血事件的发生,具有良好的消化道保护作用和安全性. 相似文献
90.
DL Eck SL Koonce RF Goldberg S Bagaria T Gibson SP Bowers SA McLaughlin 《Annals of surgical oncology》2012,19(10):3212-3217