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991.
Arthroscopic decompression of a ganglion cyst causing suprascapular nerve compression 总被引:1,自引:0,他引:1
Ganglion cysts causing suprascapular nerve compression are an uncommon cause of suprascapular nerve compression. The advent of magnetic resonance imaging (MRI) and its application in patients with shoulder pain has improved the ability to diagnose cystic lesions causing extrinsic compression of the suprascapular nerve. Traditionally, treatment of suprascapular nerve compression by a ganglion cyst has required open cyst excision through either a deltoid and infraspinatus muscle takedown or a muscle splitting approach. We present three cases of suprascapular nerve compression by a ganglion cyst in which the cyst was decompressed arthroscopically. In each case the patient's symptoms resolved after arthroscopic cyst decompression, and a postoperative MRI does not demonstrate reaccumulation of the cyst fluid. Arthroscopic ganglion cyst decompression is a well-tolerated approach to this problem that avoids the morbidity of an open surgical procedure. The absence of recurrent cyst formation combined with resolution of the symptoms attests to the success of this method. 相似文献
992.
An impingement of the rotator cuff can be caused by chronic anterior instability of the shoulder joint. This particular disease is often found in athletes engaged in overhead motion in abduction/external rotation of the arm, such as in ball sports like volleyball or European handball, racket sports like tennis or badminton, or swimming. For those patients that cannot be cured by conservative treatment such as muscular stabilization, surgical treatment is indicated: anterior reconstruction of the capsule and/or the glenoid labrum, and in addition — if necessary — subacromial decompression and revision of the rotator cuff. Between October 1988 and April 1992, we operated on 66 shoulders in 64 top athletes suffering from chronic anterior or multidirectional instability of the shoulder joint that had caused an impingement syndrome of the rotator cuff. In all cases, the athlete was unaware of the instability. Conservative treatment had been unsuccessful. Surgical treatment was successful in close to 90% of the athletes. 相似文献
993.
Haruhiko Akiyama Toshio Kawamata Tatsuo Yamada Ikuo Tooyama Tsyoshi Ishii Patrick L. McGeer 《Acta neuropathologica》1993,85(6):628-634
Summary Intercellular adhesion molecule-1 (ICAM-1) was localized immunohistochemically in postmortem brain tissue of Alzheimer's disease (AD), progressive supranuclear palsy, amyotrophic lateral sclerosis, Pick's disease, and controls. In controls, only capillaries were stained for ICAM-1. In affected areas of neurologically disease brains, a subset of reactive astrocytes was also strongly stained. In addition, there were irregular, diffuse patches of positive staining in the tissue matrix. In AD, many of these patches had dense cores which corresponded with senile plaques. Double immunostaining for glial fibrillary acidic protein and ICAM-1 indicated that some reactive astrocytes at the periphery of senile plaques were positive for ICAM-1. Within such plaques, microglial aggregates were stained intensely for leukocyte function-associated antigen-1 (LFA-1), the adhesion molecule for ICAM-1. The LFA-1/ICAM-1 system appears to play an important role in the interaction of astrocytes and microglia in several neurological diseases.Supported by grants from the Foundation for Total Health Promotion (HA), the Sasakawa Research Foundation (HA), the Alzheimer Society of B.C. and the MRC of Canada, as well as donations from individual British Columbians 相似文献
994.
Summary. The binding of acrosome reacted mammalian sperm to the egg plasma membrane initiates a series of signaling events in the egg, termed "egg activation", which lead to the completion of meiosis II and the initiation of a mitotic cell cycle. Many of these signaling events have characteristics of classical signal transduction events in somatic cells. Currently, there are two hypotheses for how sperm-induced egg activation is initiated. In the "receptor" hypothesis, the fertilizing sperm interacts with a specific egg surface receptor, and this interaction leads to signal transduction and effector activation. In the "fusion" hypothesis it is postulated that following fusion of the sperm and egg plasma membranes a soluble sperm-derived factor enters the egg's cytoplasm and activates pathways leading to egg activation. This chapter will provide an overview of the processes of cell–cell interaction and signal transduction leading to mammalian egg activation. It will concentrate on specific molecules proposed to be involved in sperm-egg interaction, signal transduction and effector mechanisms involved in egg activation, and a discussion of sperm-associated factors that have been implicated in egg activation. 相似文献
995.
996.
Platelet attachment and spreading on polystyrene surfaces: dependence on fibronectin and plasma concentration 总被引:1,自引:0,他引:1
Fibronectin promoted platelet attachment and spreading on polystyrene surfaces but was not essential if the surfaces were coated with plasma. The dependence of platelet adhesion on plasma concentration was complex. The extent of attachment and spreading was increased on surfaces treated with up to 1.0% plasma and decreased at higher plasma concentrations. The results support the hypothesis that protein adsorption is not directly related to protein concentration when surfaces are exposed to complex protein mixtures. 相似文献
997.
The aim of the study was to analyze the expression of CD44 adhesion molecule and its ligand osteopontin in papillary renal
cell tumors, and to assess the possible prognostic significance of CD44 and osteopontin expression in papillary renal cell
carcinomas. The expression of the standard and v6 exon containing isoforms of CD44 molecule, as well as of its ligand osteopontin,
was immunohistochemically evaluated in 43 papillary renal cell tumors, which included 5 adenomas and 38 carcinomas. In order
to assess their prognostic significance, the results obtained in papillary renal cell carcinomas were compared to usual clinicopathological
parameters such as tumor size, histological grade, pathological stage, and Ki-67 proliferation index. Normal renal tissue
was negative for CD44s and v6 isoforms, while the expression of osteopontin was found in distal tubular epithelial cells in
the form of cytoplasmic granular positivity. CD44s and v6 isoforms were upregulated in 22 (58%) and 12 (32%) out of 38 carcinomas,
respectively. Among all clinicopathological parameters examined, we only found significant association of CD44s-positive carcinomas
with lower pathological stage (p=0.026). Papillary renal cell adenomas were generally negative for CD44s, except for focal
positivity found in one sample. The osteopontin protein was detected in all adenomas and all papillary renal cell carcinomas,
except one. Our results show constitutive expression of osteopontin in papillary renal tumors, including papillary renal cell
adenomas. The upregulation of CD44s and v6 isoforms, although found in a considerable number of papillary renal cell carcinomas,
does not appear to have any prognostic value in this type of renal cancer.
This work was supported by the Ministry of Science, Education and Sport of the Republic of Croatia (grant 0062066). 相似文献
998.
Bulbuller N Ilhan YS Kirkil C Cetiner M Gogebakan O Ilhan N 《The Journal of surgical research》2005,125(1):94-97
BACKGROUND: Peritoneal adhesions are pathological fibrotic bands developing after mesothelial damage. Transforming growth factor beta-1 (TGF-beta1) has mitogenic activities for macrophages and fibroblasts. Over-expression of TGF-beta1 has been implicated in the pathogenesis of several fibrotic disorders. Angiotensin II increases the expression of the TGF-beta1 in fibroblasts. The aim of the study was to investigate the effect of angiotensin converting enzyme inhibitor (ACE) on intraperitoneal adhesions. MATERIALS AND METHODS: Thirty male Wistar albino rats were divided into two groups. In the first procedure, laparotomy was performed through a 3-cm midline incision. Ileum was divided above 10 cm from ileocecal valve and a single-layer ileoileal anastomosis was performed. Although no treatment was given to rats in group 1, lisinopril (an ACE inhibitor) was given to rats in group 2 for postoperative 7 days in drinking water. Estimated amount of supplied lisinopril was 6.5 mg/kg/day. On postoperative 8th day, relaparotomy was performed and adhesions were evaluated. At the same time, blood samples were taken for TGF-beta1 measurements. RESULTS: Adhesion severity was significantly less in the ACE inhibitor group (P < 0.001). While mean TGF-beta1 level was 860.3 +/- 108.1 pg/dl (mean +/- SD) in control group, it was 335.8 +/- 52.4 pg/dl in ACE inhibitor group (P < 0.001). There was a significant correlation between serum TGF-beta1 levels and grade of adhesions (r = 0.948). CONCLUSION: It was concluded that ACE inhibitors might be useful for preventing peritoneal adhesions. 相似文献
999.
Denoyer D Perek N Le Jeune N Cornillon J Dubois F 《European journal of nuclear medicine and molecular imaging》2005,32(7):820-827
Purpose Although a number of prognostic indicators have been developed, it is still difficult to predict the biological behaviour of all cancer types. 99mTc-(V)-DMSA (V DMSA) uptake and focal adhesion kinase (FAK) expression and activation level could be potential agents for this purpose. We hypothesised the existence of a correlation between V DMSA, whose uptake is linked to phosphate ions, essential compounds for tumour growth and cell proliferation, and the adhesion protein FAK, whose elevated expression and level of constitutive activation are implicated in cancer progression. The aim of this study was to assess the relationship between V DMSA incorporation rate and FAK expression and activation by phosphorylation on tyrosine 397 residue.Methods We determined V DMSA uptake in six different cancer cell lines and we measured FAK expression and activation by using Western Blotting analysis. Correlations with factors known to be associated with poor prognosis, such as invasive potential, resistance to chemotherapy and proliferation rate, were also investigated. Results The cell lines exhibited different V DMSA incorporation rates. In addition, these cells showed the same FAK expression, but various degrees of activation. A correlation was observed between V DMSA uptake and level of FAK phosphorylation and between V DMSA or constitutive FAK activation and proliferation rate. However, no correlation was shown between these parameters and the other factors tested, i.e. invasive potential and anticancer drug resistance.Conclusion The results of this in vitro study clearly demonstrate that phosphorylation of FAK, proliferation rate and V DMSA uptake are closely related. Because proliferation and a high level of constitutive FAK activation are linked to cancer progression, it can be assumed that in vivo V DMSA uptake reflects tumour aggressiveness. 相似文献
1000.
BACKGROUND: Intestinal milking is a frequently used method in abdominal surgery for various purposes; although it is frequently used for eliminating distension, moving faeces, bezoar or other foreign objects proximal or distal, there are no experimental or prospective studies in the surgical literature with respect to complications of the method. The purpose of the present study was to investigate complications of the milking process in an experimental model. METHODS: Forty-four outbred, 8-month old Wistar albino male rats with weights ranging between 195 and 225 g were used. Four rats were used for preliminary study. The other 40 rats were divided into two equal groups. In the study group (n = 20), a plastic sphere, 3 mm in diameter was sent to the stomach via oro-gastric tubes. This sphere was then moved into the cecum by milking. In the control group rats (n = 20) the small intestines were manipulated at 1-cm intervals but milking was not performed. RESULTS: In the study group six rats (30%) developed grade 1, 11 rats (55%) developed grade 2, and three rats (15%) developed grade 3 peritoneal adhesion. In the control group, 18 rats (90%) had no adhesions and only two rats (10%) developed grade 1 adhesion (chi(2) = 34, P < 0.0001). In the study group, four rats (20%) had small bowel obstruction, whereas no rats in the control group developed small bowel obstruction (Fisher's P > 0.05). Peritoneal smear culture was positive in 11 rats (55%) in the study group, whereas it was positive in two rats (10%) in the control group (Fisher's P < 0.01). CONCLUSIONS: Intestinal milking is a process that can cause severe peritoneal adhesions and peritoneal contamination, which may lead to small bowel obstruction. Avoiding milking to the extent possible in eliminating distension intraluminal material that may cause obstruction, and preferring alternative methods is important for reducing postoperative morbidity. 相似文献