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21.
额部扩张皮瓣的手术设计   总被引:6,自引:2,他引:4  
目的 探讨额部扩张皮瓣的手术设计。方法 对121例额、颞部瘢痕、斑痣、血管瘤等皮肤病变切除后的患者采用额部扩张皮瓣进行修复,并比较滑行皮瓣、易位皮瓣及旋转皮瓣的手术效果。结果 115例患者取得良好的手术效果,修复后皮肤弹性良好、颜色较理想、瘢痕较细小;4例患者扩张皮瓣的远端有0.5~1.0cm的坏死,行Ⅱ期瘢痕切除缝合术;2例患者有单侧眉上提,半年后好转。结论 易位皮瓣术后瘢痕明显,尽量少用或不用;旋转皮瓣可以充分利用扩张后“过剩”的皮肤。是一种值得推广的额部皮瓣设计方法。对皮瓣的周密设计并了解不同皮瓣的优缺点。对手术效果及术后并发症的预防非常重要。  相似文献   
22.
下腹部多个真皮下血管网皮瓣在手外伤修复中的应用   总被引:10,自引:3,他引:7  
目的:应用下腹部多个真皮下血管网皮瓣修复手外伤,方法:在下腹形成以旋髂浅血管为蒂的髂腰部皮瓣及以腹壁浅血管为蒂的下腹部皮瓣,二皮瓣共蒂形成双叶皮瓣,同时将其修薄,形成有轴心血管的真皮下血管网皮瓣,修复两指完全脱套伤。在下腹部形成多个真皮下血管网的任意皮瓣,修复多个指背皮肤缺损伴有肌腱及骨外露的创面。供区如不能直接拉拢缝合,可取断层皮片修复供区创面.结果:本组10例中,8例采用下腹部双叶真皮下血管网轴型皮瓣修复,2例采用下腹部真皮下血管网任意皮瓣修复,术后效果。结论:采用多个真皮下血管网皮瓣修复手外伤的创面,伤指不需并指,去脂,分指,术后外形佳,是目前较理想的修复手外伤的手术方法。  相似文献   
23.
24.
Qureshi  Bashir 《JAMA》1998,279(22):1838-1839
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25.
Cervical smears were reviewed from patients in whom a cytological abnormality was followed, after an interval without interference, either by regression to `negative' or else by progression to invasive carcinoma. Twenty-eight cases were from a previously analysed series with positive smears and an interval of at least two years before investigation, resulting from refusal or failure to trace. Slides were also reviewed from 25 cases in which `positive' smears had regressed to negative without escaping from surveillance, and from 10 patients subsequently developing invasive carcinoma whose previous slides, taken several years earlier, showed abnormalities on review. None of these 63 patients had any biopsy or other surgical procedure to the cervix between the initial smear and the outcome.

Slides showing `superficial cell dyskaryosis' and/or well-differentiated `parabasal cell dyskaryosis' were found only among the groups with subsequent regression. Those showing dissociated poorly differentiated dyskaryotic parabasal cells regressed to negative in two cases and progressed to invasion in nine. This suggests that many examples of spontaneous regression correspond to mild dysplasias which are not precancerous, and overdiagnosis must often have resulted in unnecessary surgical procedures in the past.

`Regressing' and `progressing' groups both included cases in which the spatula had removed coherent pieces of undifferentiated epithelium. These are difficult to interpret cytologically. In nine of them (including four which regressed) the cytological picture was that of carcinoma in situ. The remainder (14 cases) were probably examples of reserve cell hyperplasia, and it is noteworthy that, of the 21 cases subsequently progressing to invasive carcinoma, five were preceded by appearances of this type. It is concluded that cell aggregates suggesting an unusual degree of reserve cell hyperplasia are a danger signal and require careful surveillance.

  相似文献   
26.
Rhodopseudomonas (Rhodobacter) sphaeroides diphosphoryl lipid A is a relatively inert species of lipid A but has been shown to antagonize the effects of toxic lipopolysaccharide (LPS) both in vivo and in vitro. The antagonist and its monophosphoryl derivative were examined for the ability to block tumor necrosis factor synthesis and reverse tolerance induction in vitro in macrophage cultures stimulated with bioactive preparations of smooth LPS, rough LPS, diphosphoryl lipid A, and monophosphoryl lipid A. Inhibition of agonist activity and reversal of tolerance by these novel penta-acylated lipid A antagonists provides new insight into macrophage-LPS interactions.  相似文献   
27.
This report describes a low-grade B-cell lymphoma of mucosa associated lymphoid tissue (MALT) involving the thymus of a 63-year-old woman with features suggestive of a connective tissue disease. Sections of the thymic lesion and of a lung biopsy performed at the same operation were examined histologically and by immunohistochemistry using the monoclonal antibodies CD45, CD20, CD79a, CD3, CD45RO, and AE1/AE3. Polymerase chain reaction (PCR) for immunoglobulin heavy chain gene rearrangement was also performed. The dense infiltrate of small lymphoid cells intimately admixed with ramifying epithelial elements, some of which had undergone cystic change, closely resembled a thymoma. The lymphoid infiltrate comprised centrocyte-like cells, small lymphocytes, plasma cells, and blasts. Most of the lymphoid cells were immunoreactive with the B-cell markers CD20 and CD79a, and PCR showed clonal immunoglobulin heavy chain gene rearrangement. The lung biopsy showed dense infiltration by small lymphoid cells, morphologically suggestive of lymphoid interstitial pneumonia. However, PCR showed a weak band in the amplification for immunoglobulin heavy chain gene rearrangement, identical to that within the thymus and suggesting either recirculation of cells to accumulated MALT or subhistological lymphoma. MALT lymphoma may rarely involve the thymus, and pathologists should be aware of this to avoid misdiagnosis as a thymoma. Immunohistochemical and/or molecular studies are of value in this regard. MALT lymphomas of the thymus, common with those arising in other organs, may develop in the setting of a connective tissue disease.  相似文献   
28.
Microarray-based comparative genomic hybridization (CGH) provides a powerful tool for whole genome analyses and the rapid detection of genomic variation that underlies virulence and disease. In the field of Plasmodium research, many of the parasite genomes that one might wish to study in a high throughput manner are not laboratory clones, but clinical isolates. One of the key limitations to the use of clinical samples in CGH, however, is the miniscule amounts of genomic DNA available. Here we describe the successful application of multiple displacement amplification (MDA), a non-PCR-based amplification method that exhibits clear advantages over all other currently available methods. Using MDA, CGH was performed on a panel of NF54 and IT/FCR3 clones, identifying previously published deletions on chromosomes 2 and 9 as well as polymorphism in genes associated with disease pathology.  相似文献   
29.
This study tested whether concordance could be achieved for abnormal inflammation in the basal decidua of placental specimens among 6 pathologists experienced in placental pathology. Thirty microscope slides were evaluated by the pathologists for chronic deciduitis. They also scored the severity and extent of inflammation and the presence of plasma cells. No definition of chronic deciduitis was provided. Concordance (5/6 or 6/6 agreement) was achieved in 23 cases (76%). Spearman's rank correlation showed that the diagnosis of chronic deciduitis was almost identical to the assessment of the severity of the inflammation. A regression analysis showed that the perception of severity (and hence chronic deciduitis) was influenced by the other 2 variables, extent and plasma cells. The results were shared with the pathologists, and 25 cases (excluding those with previous 6/6 consensus) were reevaluated. Concordance was now achieved in the 83% of those remaining cases. Using a threshold based on the severity and the extent of lymphocytes, and the presence of plasma cells, pathologists are able to diagnose chronic deciduitis with sufficient concordance to be of value in clinical correlation studies.  相似文献   
30.
Diphosphoryl lipid A from the lipopolysaccharide (LPS) of Rhodobacter sphaeroides (Rs-DPLA) has been demonstrated to block in mice and guinea pigs the increase in the serum tumor necrosis factor (TNF) response induced by highly purified deep rough chemotype LPS from Escherichia coli D31m4 (ReLPS). The present study was designed to determine the role of corticosterone induction by Rs-DPLA and its effect on TNF regulation and survival in lethal endotoxin shock models and to evaluate the ability of Rs-DPLA to induce endotoxin tolerance. Administration of a 100-fold excess of Rs-DPLA 1 h prior to ReLPS administration inhibited the characteristic peak in serum TNF levels induced by LPS. Inhibition was apparent in normal and D-galactosamine (GalN)-sensitized mice and occurred at the pretranslational level, as splenic TNF and interleukin-1 beta mRNAs were present in lower amounts in LPS-stimulated mice pretreated with Rs-DPLA. Consistent with its effects in reducing serum TNF levels, Rs-DPLA pretreatment protected GalN-sensitized mice from a lethal ReLPS challenge. In contrast, Rs-DPLA did not inhibit the increase in the serum TNF response or protect against a lethal ReLPS challenge in parallel experiments with adrenalectomized (Adrex) mice, for which the 50% lethal dose of ReLPS was comparable to that for GalN-sensitized mice. Furthermore, Rs-DPLA appeared to prime Adrex animals and increase the magnitude of the serum TNF response to a suboptimal LPS stimulus. Priming by Rs-DPLA, however, was not observed in normal or GalN-sensitized mice. Although Rs-DPLA by itself was nontoxic and unable to elevate serum TNF levels in any of the models investigated, it did induce a significant increase in the serum corticosterone response and was capable of inducing endotoxin tolerance in normal mice. The inability of Rs-DPLA to protect Adrex mice from a lethal ReLPS stimulus or to inhibit the increase in the serum TNF response suggests that the protective effect of Rs-DPLA in normal or GalN-sensitized animals occurs through corticosterone induction. These results support the concept that endogenous glucocorticoids can modulate the endotoxic effects of LPS by inhibiting the synthesis of inflammatory cytokines.  相似文献   
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