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51.
Phase I trial of the positron-emitting Arg-Gly-Asp (RGD) peptide radioligand 18F-AH111585 in breast cancer patients. 总被引:3,自引:0,他引:3
Laura M Kenny R Charles Coombes Inger Oulie Kaiyumars B Contractor Matthew Miller Terence J Spinks Brian McParland Pamela S Cohen Ai-Min Hui Carlo Palmieri Safiye Osman Matthias Glaser David Turton Adil Al-Nahhas Eric O Aboagye 《Journal of nuclear medicine》2008,49(6):879-886
The integrin alpha v beta3 receptor is upregulated on tumor cells and endothelium and plays important roles in angiogenesis and metastasis. Arg-Gly-Asp (RGD) peptide ligands have high affinity for these integrins and can be radiolabeled for PET imaging of angiogenesis or tumor development. We have assessed the safety, stability, and tumor distribution kinetics of a novel radiolabeled RGD-based integrin peptide-polymer conjugate, 18F-AH111585, and its feasibility to detect tumors in metastatic breast cancer patients using PET. METHODS: The biodistribution of 18F-AH111585 was assessed in 18 tumor lesions from 7 patients with metastatic breast cancer by PET, and the PET data were compared with CT results. The metabolic stability of 18F-AH111585 was assessed by chromatography of plasma samples. Regions of interest (ROIs) defined over tumor and normal tissues of the PET images were used to determine the kinetics of radioligand binding in tissues. RESULTS: The radiopharmaceutical and PET procedures were well tolerated in all patients. All 18 tumors detected by CT were visible on the 18F-AH111585 PET images, either as distinct increases in uptake compared with the surrounding normal tissue or, in the case of liver metastases, as regions of deficit uptake because of the high background activity in normal liver tissue. 18F-AH111585 was either homogeneously distributed in the tumors or appeared within the tumor rim, consistent with the pattern of viable peripheral tumor and central necrosis often seen in association with angiogenesis. Increased uptake compared with background (P = 0.002) was demonstrated in metastases in lung, pleura, bone, lymph node, and primary tumor. CONCLUSION: 18F-AH111585 designed to bind the alpha v beta3 integrin is safe, metabolically stable, and retained in tumor tissues and detects breast cancer lesions by PET in most anatomic sites. 相似文献
52.
Roger W. Byard Regula Wick John D. Gilbert Terence Donald 《Forensic science, medicine, and pathology》2008,4(3):187-192
It is generally held that leukocytes are found within bruised subcutaneous tissues within 4–12 h of injury as part of a standard
cellular response to trauma. As a corollary, the absence of leukocytes is often cited as evidence of more recent injury. To
investigate how long after injury it may be before a leukocyte response occurs selected bruises from three children aged 27,
11, and 3 months, respectively, were examined microscopically. All of the children had sustained lethal head trauma, with
survival on life-support equipment for some time in hospital, and with bruises of at least 24-h duration confirmed by medical
evaluation (at 30, 44, and 79 h from the time of initial medical evaluation to death). Histologic examination of selected
lesions in all three cases revealed extravasation of red blood cells within subcutaneous tissues, but no leukocyte infiltration
or other cellular reaction. Other bruises in these children exhibited a standard inflammatory response. This study has shown
that selected bruises in three children were present for at least 30 h without a leukocyte infiltrate. Caution should, therefore,
be exercised in assigning too rigid a time course to bruising in infants and young children based on a lack of a vital reaction,
as the absence of leukocytes within soft tissues of bruised skin in these cases may not necessarily indicate that the injuries
are recent. Variability in tissue response may also occur in different bruises in the same individual. Whether severe craniocerebral
trauma played a role in delaying the cellular response in these particular injuries is unclear. 相似文献
53.
Graft injury in relation to graft size in right lobe live donor liver transplantation: a study of hepatic sinusoidal injury in correlation with portal hemodynamics and intragraft gene expression 总被引:23,自引:0,他引:23 下载免费PDF全文
Man K Fan ST Lo CM Liu CL Fung PC Liang TB Lee TK Tsui SH Ng IO Zhang ZW Wong J 《Annals of surgery》2003,237(2):256-264
OBJECTIVE: To investigate the degree and mechanism of hepatic sinusoidal injury in different graft sizes in right lobe live donor liver transplantation (LDLT). SUMMARY BACKGROUND DATA: Liver grafts from living donors are likely to be small-for-size for adult recipients. Graft injury after reperfusion is common, but the mechanism and degree of injury remain unclear. The hepatic sinusoidal injury in different graft sizes and its relationship with portal hemodynamics and intragraft gene response at the early phase after reperfusion have not been studied in right lobe LDLT. METHODS: From May 2000 to November 2001, 40 adults receiving right lobe LDLT had portal pressure measured continuously before and after reperfusion. Liver biopsies were taken before and after reperfusion for detection of vasoregulatory genes (endothelin-1 and endothelial nitric oxide synthase) and heat shock genes (heat shock protein 70 and heme oxygenase-1), and electron microscope examination. Blood samples from the portal vein and suprahepatic inferior vena cava were taken for the measurement of plasma nitric oxide level. RESULTS: The recipients were grouped according to the ratio of graft weight to estimated standard liver weight: group 1 (n = 10), less than 40%; group 2 (n = 21), 40% to 60%; and group 3 (n = 9), more than 60%. The portal pressures recorded after reperfusion in group 1 were significantly higher within 30 minutes of reperfusion than those in groups 2 and 3. After reperfusion, the intragraft endothelin-1 mRNA level in group 1 increased by 161% of the basal level but decreased by 31.5% and 62% of the basal level in groups 2 and 3, respectively. The intragraft mRNA level of heme oxygenase-1 in groups 1 and 2 decreased by 75.5% and 25.3% of the basal level respectively but increased by 41% of basal level in group 3. The intragraft protein level of heat shock protein 70 decreased by 50 ng/mL after reperfusion in group 1 but increased by 12.4 ng/mL and 0.6 ng/mL in groups 2 and 3, respectively. The portal vein plasma nitric oxide level decreased more significantly after reperfusion in group 1 than in group 2. Electron microscope examination of liver biopsies in group 1 showed tremendous mitochondrial swelling as well as irregular large gaps between the sinusoidal lining cells. There were two hospital deaths in group 1 and none in the other two groups. CONCLUSIONS: Patients implanted with grafts less than 40% of standard liver weight suffered from transient portal hypertension early after reperfusion. The phenomenon was accompanied by intragraft upregulation of endothelin-1 and ultrastructural evidence of sinusoidal damage. The transient portal hypertension after reperfusion, subsequent endothelin-1 overexpression, and plasma nitric oxide level reduction, together with downregulation of heme oxygenase-1 and heat shock protein 70, may account for the small-for-size graft injury. 相似文献
54.
Nam TW Yoo CI Kim HT Kwon CH Park JY Kim YK 《Journal of bone and mineral metabolism》2008,26(6):551-560
The present study was undertaken to evaluate effects of quercetin, a major dietary flavonoid occurring in foods of plant origin,
on cell viability and migration of osteoblastic cells. Quercetin inhibited cell viability, which was largely attributed to
apoptosis, in a dose-and time-dependent manner in osteoblastic cells. Similar cytotoxicity of quercetin was observed in adipose
tissue-derived stromal cells. Quercetin exerted a protective effect against H2O2-induced cell death, whereas it increased TNF-α-induced cell death. Western blot analysis showed that quercetin induced activation
of ERK and p38, but not JNK. Quercetin-induced cell death was prevented by the ERK inhibitor PD98059, but not by inhibitors
of p38 and JNK. Quercetin increased Bax expression and caused depolarization of mitochondrial membrane potential, which were
inhibited by PD98059. Quercetin induced caspase-3 activation, and the quercetininduced cell death was prevented by caspase
inhibitors. Quercetin inhibited cell migration, and its effect was prevented by inhibitors of ERK and p38. Taken together,
these findings suggest that quercetin induces apoptosis through a mitochondria-dependent mechanism involving ERK activation
and inhibits migration through activation of ERK and p38 pathways. Quercetin may exert both protective and deleterious effects
in bone repair. 相似文献
55.
Phil Hyun Song Young Don Kim Hyun Tae Kim Hwa Su Lim Chang Ho Hyun Joon Hyung Seo Eun Sang Yoo Choal Hee Park Hee Chang Jung 《BJU international》2009,104(8):1113-1117
OBJECTIVE
To evaluate the long‐term results and predictive risk factors for efficacy after the tension‐free vaginal tape (TVT) procedure for treating female stress urinary incontinence (SUI).PATIENTS AND METHODS
Inall, 306 women (mean age 50.7 years, sd 8.7) who had a TVT procedure for SUI were selected and followed ≥7 years (mean 92.3 months, range 84–110) after surgery. We analysed the long‐term results, the variables predictive of cure rates, and patient satisfaction.RESULTS
The overall 7‐year cure rate was 84.6%, with a satisfaction rate of 69.3%. The cure rates were lower in patients with high‐grade SUI (50% in grade III, 82.8% in grade II and 90.7% in grade I; P < 0.001). On multivariate analysis, there were no independent risk factors related to cure rate, and urgency was the only factor independently associated with patient satisfaction (P = 0.008; odds ratio 2.47). Seventy‐one patients (23.2%) had complications at the 1‐month follow‐up after surgery, but only eight (2.6%) had complications at the 7‐year follow‐up, including mesh exposure in six and de novo urgency in two.CONCLUSION
The absence of long‐term adverse events associated with the TVT procedure, and high subjective and objective 7‐year success rates with no independent predictive factors affecting the long‐term cure rate, make the TVT procedure a recommendable surgical treatment for female SUI. 相似文献56.
The lateral surgical approach to jugular foramen schwannomas (JFS) may result in complications such as temporary facial nerve
palsy (FNP) and hearing loss due to the complicated anatomical location. Ten patients with JFS surgically treated by variable
methods of lateral approach were retrospectively reviewed with emphasis on surgical methods, postoperative FNP, and lower
cranial nerve status. Gross total removal of the tumors was achieved in eight patients. Facial nerves were rerouted at the
first genu (1G) in six patients and at the second genu in four patients. FNP of House–Brackmann (HB) grade III or worse developed
immediately postoperatively in six patients regardless of the extent of rerouting. The FNP of HB grade III persisted for more
than a year in one patient managed with rerouting at 1G. Among the lower cranial nerves, the vagus nerve was most frequently
paralyzed preoperatively and lower cranial nerve palsies were newly developed in two patients. The methods of the surgical
approach to JFS can be modified depending on the size and location of tumors to reduce injury of the facial nerve and loss
of hearing. Careful manipulation and caution are also required for short facial nerve rerouting as well as for long rerouting
to avoid immediately postoperative FNP. 相似文献
57.
Yang Hwa Ng 《Journal of pediatric surgery》2009,44(2):422-426
Purpose
Recent studies suggest that testicular descent is accomplished by outgrowth of the gubernaculum from the abdominal wall. The tip of the gubernaculum has been proposed as the primary site of growth, similar to an embryonic limb bud. We aimed to determine the maximum site of growth in organ culture.Methods
Gubernacula from 1-day-old Sprague-Dawley rats (n = 40) were collected and divided into 4 groups as follows: whole gubernaculum (control), truncated gubernaculum (tip excised), gubernacular tip alone, and grafted gubernaculum with an extra tip on its side. Tissues were cultured with or without calcitonin gene-related peptide (CGRP) (714nmol/L) in medium for 24 hours. The area of each gubernaculum was determined by “Image J” analysis of digital photos collected via a Leica Wild M28 microscope (Leica Microsystems, Wetzler GmbH Germany) taken before and after culture.Results
In organ culture, the neonatal rat gubernaculum normally shrank 10% to 15%, but this was prevented by the presence of exogenous CGRP (0.8% vs 11.8%; P < .003). By contrast, gubernacula with their tips excised were not affected by CGRP (3.4% vs 4.7%; not significant). Gubernacular tips alone did respond to CGRP (2.7% vs 13.5%; P < .03). Transplantation of the tip to another gubernaculum caused it to develop 2 tips.Conclusions
These results suggest that the rat gubernaculum contains a growth centre in its distal tip that can respond to CGRP. This is consistent with a limb bud model of gubernacular growth during the inguinoscrotal descent of the testis. 相似文献58.
Jeong-Im Sin Jung-Min Kim Sung Hwa Bae In Hee Lee Jong Sup Park Hun Mo Ryoo 《Molecular therapy》2009,17(5):906-913
Adoptive cytotoxic T lymphocyte (CTL) therapy has an important implication in treating cancer patients. Here, we investigate whether adoptive transfer of human papillomavirus (HPV) E7-specific CTL can enhance tumor chemoresponse using an established cervical cancer animal model. Cisplatin-based chemotherapy plus CTL therapy showed an improved therapeutic effectiveness, along with antitumor protective responses to a parental tumor cell rechallenge. Cisplatin treatment dose-dependently increased the expression of Fas, intercellular adhesion molecule (ICAM)-1, and major histocompatibility complex (MHC) class I antigens (Ags) on tumor cells in vitro. However, CTL-expressing FasL failed to improve antitumor activity in vitro and in animals, resulting from nonfunctional Fas expressed on tumor cells. In contrast, ethylene glycol tetraacetic acid (EGTA) treatment blocked increased sensitivity of cisplatin-treated tumor cells to CTL-mediated killing in vitro, suggesting an important role of the perforin/granzyme-mediated pathway for improved therapeutic effectiveness. This notion was further confirmed by perforin knockout animal studies. Thus, this study shows that (i) modulation of Ag (Fas, ICAM-1) expression by tumor cells has little effect on their increased sensitivity to CTL-mediated killing, (ii) improved therapeutic effectiveness is mediated mainly through the perforin/granzyme-mediated tumor killing pathway, and (iii) a combination of chemotherapy and adoptive E7-specific CTL transfer augments antitumor therapeutic activity in vivo. This finding may have important implications for treating HPV-associated cervical cancer. 相似文献
59.
Chi‐Yuan Chen Shih‐Hwa Chiou Chih‐Yang Huang Chia‐Ing Jan Shu‐Chun Lin Wen‐Yuan Hu Shiu‐Huey Chou Chung‐Ji Liu Jeng‐Fan Lo 《The Journal of pathology》2009,219(3):347-355
Human tumourous imaginal disc (Tid1), a human homologue of the Drosophila tumour suppressor protein Tid56, is involved in multiple intracellular signalling pathways such as apoptosis, cell proliferation, and cell survival. Here, we investigated the anti‐tumourigenic activity of Tid1 in head and neck squamous cell carcinoma (HNSCC) in vitro and in vivo. Firstly, the clinical association between Tid1 expression and progression of HNSCC was explored. It was found that expression of Tid1 was negatively associated with tumour status, recurrence, and survival prognosis using immunohistochemical analysis of primary HNSCC patient tumour tissue. Secondly, ectopic expression of Tid1 in HNSCC cells was shown to significantly inhibit cell proliferation, migration, invasion, anchorage‐independent growth, and xenotransplantation tumourigenicity. Thirdly, we showed that overexpression of Tid1 attenuated EGFR activity and blocked the activation of AKT in HNSCC cells, which are known to be involved in the regulation of survival in HNSCC cells. On the other hand, ectopic expression of constitutively active AKT greatly reduced apoptosis induced by Tid1 overexpression. Together, these findings suggest that Tid1 functions as a tumour suppressor in HNSCC tumourigenesis. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
60.