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81.
Timothy A. Jennings MD Ng Bernard MD Ann Boguniewicz MD Muzaffar Khan MD Donald Rice MD James Figge MD 《Endocrine pathology》1998,9(4):353-361
Hemorrhagic adrenal pseudocysts are uncommon nonneoplastic lesions that have been reported as secondary to intraparenchymal
hemorrhage or alternatively related to endothelial (vascular) cysts. Ultrastructural and immunohistochemical evidence in support
of the latter has been presented, but the exact nature of hemorrhagic adrenal pseudocysts remains poorly defined. We evaluated
six surgical specimens of hemorrhagic adrenal pseudocysts using immunohistochemical staining for CD31 and CD34, as well as
conventional histochemistry. All six cases had hemorrhagic contents within a wall of variable thickness possessing focal areas
of linear, disrupted elastin, and smooth muscle. Three cases demonstrated extensive thrombosis with organization, including
papillary endothelial hyperplasia, simulating angiosarcoma. In these cases, CD31 and CD34 staining decorated areas of papillary
endothelial hyperplasia as well as foci of the internal cyst lining, whereas the other cases were negative for both antibodies.
Of interest is the history of FNA prior to surgical resection in three cases of hemorrhagic adrenal pseudocysts, two of which
showed papillary endothelial hyperplasia. The presence of papillary endothelial hyperplasia and our immunohistochemical findings
support, the conclusion that adrenal pseudocysts are posthemorrhagic and derive from vascular disruption. Furthermore, FNA
or other interventional studies may be associated with papillary endothelial hyperplasia in hemorrhagic adrenal pseudocysts. 相似文献
82.
Ryohei Katoh Koichi Suzuki Akihiro Hemmi Akira Kawaoi 《Virchows Archiv : an international journal of pathology》1993,422(4):301-306
To elucidate the significance and nature of calcium oxalate crystals in the thyroid, we studied these crystals clinicopathologically and immunohistochemically in 182 normal thyroids from patients autopsied within 5 h of death. Under polarized light, calcium oxalate crystals showed brilliant birefringence and were invariably found within the colloid. The crystals were found in 73.1% of all cases but were more prevalent and denser in older individuals, with the highest prevalence (85.2%) being observed in those over 70 years of age. No crystals were seen in those under 10 years of age. Although underlying diseases seemed to have little influence, post-mortem delay apparently affected the prevalence and density of occurrence since the crystals tended to disappear with hours after death. An immunohistochemical study using anti-thyroid hormone antibodies revealed that the crystals were within negatively or weakly stained colloid and were not common in strongly stained colloid. These findings support the hypothesis that the occurrence of calcium oxalate crystals in normal human thyroid is associated with a low functional state of the thyroid follicles. 相似文献
83.
Isolation and radiation hybrid mapping of a dinucleotide repeat polymorphism at the human calcium-sensing receptor (CASR) locus 总被引:2,自引:0,他引:2
Kazuhiro Tsukamoto Ikuyo Watanabe Tadayoshi Shiba M. Emi 《Journal of human genetics》1998,43(4):280-282
Calcium-sensing receptor (CASR) in parathyroid gland regulates calcium homeostasis by sensing decreases in extracellular
calcium levels and effecting an increase in secretion of parathyroid hormone. A polymorphic dinucleotide (CA) sequence was
isolated from a genomic clone containing the human CASR gene and was mapped to 3q13.3–q21. This polymorphism will be useful in the genetic study of disorders affecting calcium metabolism,
such as hypercalcemia, hypocalcemia, osteoporosis, hyperparathyroidism, and hypoparathyroidism.
Received: June 2, 1998 / Accepted: June 24, 1998 相似文献
84.
Hypothalamic neurons producing growth hormone-releasing factor (GRF) have been characterized by immunohistochemistry in monkey hypothalamus, using an antiserum raised against hpGRF1-40, a peptide with GRF activity isolated from a human pancreatic tumor. Cell bodies with hpGRF immunoreactivity were found in arcuate and ventromedial nuclei. From these neurons, bundles of fibers innervate median eminence and appear to terminate in contact with portal vessels. In addition to median eminence, hpGRF immunoreactive fibers were found mostly in the anterior hypothalamus and the arcuate and ventromedial nuclei where they give perineuronal endings. These results correlate with earlier physiological data on hypothalamic control of growth hormone secretion and suggest that GRF is also involved in interneuronal relationships related or unrelated to neurohumoral control of pituitary secretions. 相似文献
85.
86.
用选择性作用于外周型苯二氮(艹卓)受体的标记配体[~3H]PK11195检测了Wistar大鼠分离的肾上腺皮质球状带细胞上苯二氮(艹卓)受体的结合动力学参数,结果表明Wistar大鼠在双侧肾切除后36小时、其球状带细胞苯二氮(艹卓)受体结合[~3H]PK11195的最大容量(B_(max))显著高于假手术组和正常对照组的相应数值,三组的B_(max)分别为12.1±1.1、6.6±1.3和5.6±1.8(pmol/10~6cells),三组的K_D值则无显著差异。 相似文献
87.
A case of mixed medullary follicular carcinoma of the thyroid is reported. Grossly, the tumor was a solid, grayish white, well circumscribed mass without lymph node metastasis. Microscopically, the tumor showed both medullary and follicular areas. The follicular areas occupied discrete portions of the tumor, and were considered to be neoplastic. Tumor cells in the medullary area were polyhedral or spindle-shaped. There was no amyloid deposition within the tumor. Immunohistochemically, tumor cells in the medullary area were positive for calcitonin and negative for thyroglobulin. Some cells lining the follicles were positive for thyroglobulin. By electron microscopy, two types of tumor cell were observed. One type contained numerous cytoplasmic secretory granules, whereas the other type had few granules and showed a prominent rough endoplasmic reticulum. These findings suggested that this mixed medullary follicular carcinoma of the thyroid presented neoplastic changes within a common cell lineage. 相似文献
88.
缺碘和氟中毒对大鼠甲状腺的协同作用 总被引:2,自引:0,他引:2
实验用Wistar大鼠212只,按饮食中碘和氟含量不同随机分为五组,实验期为7个月。结果显示:摄碘正常的大鼠长期饮用30ppm氟水后引起甲状腺功能和形态的严重损害,而饮用10ppm氟水的大鼠仅见甲状腺滤泡上皮超微结构的轻度异常变化;单纯性缺碘大鼠甲状腺肿大并伴有代偿性功能变化,缺碘并饮用10ppm氟水的大鼠在其甲状腺肿大的同时伴有明显的形态结构损伤及甲状腺代偿功能抑制,甚至功能低下。 相似文献
89.
Anne M. Von Euler R. Margareta Mü ller Godfried M. Roomans Ove Ceder 《Ultrastructural pathology》1983,5(1):37-44
The effects of cystic fibrosis (CF) serum and culture medium from CF fibroblasts on ion distribution in rat submandibular gland cells were investigated by X-ray microanalysis. These effects were compared to the effects of normal serum and culture medium from normal fibroblasts, of cholinergic and adrenergic agonists, and of the uncoupler 2,4-dinitrophenol.
Incubation of gland tissue with CF serum or normal serum caused a significant decrease in potassium and calcium concentrations and an increase in sodium in mucous acinar and serous granular duct cells. CF serum gave a significantly larger decrease of the potassium level than normal serum.
Culture medium from CF fibroblasts altered the cellular ion content in a way similar to CF serum. Exposure to medium from cultured normal fibroblasts did not affect the elemental composition of the gland cells significantly, compared to incubation with fresh medium or buffer. Hence, fibroblast culture medium is more suitable than serum to test specific effects of CF-associated factors.
The changes in elemental composition of gland eelIs caused by CF serum or CF fibroblast culture medium mimic some of the effects of the agonist car-bachol. They could, however, also in part result from nonspecific changes in membrane permeability. 相似文献
Incubation of gland tissue with CF serum or normal serum caused a significant decrease in potassium and calcium concentrations and an increase in sodium in mucous acinar and serous granular duct cells. CF serum gave a significantly larger decrease of the potassium level than normal serum.
Culture medium from CF fibroblasts altered the cellular ion content in a way similar to CF serum. Exposure to medium from cultured normal fibroblasts did not affect the elemental composition of the gland cells significantly, compared to incubation with fresh medium or buffer. Hence, fibroblast culture medium is more suitable than serum to test specific effects of CF-associated factors.
The changes in elemental composition of gland eelIs caused by CF serum or CF fibroblast culture medium mimic some of the effects of the agonist car-bachol. They could, however, also in part result from nonspecific changes in membrane permeability. 相似文献
90.
Fundic gland polyps (Elster's cysts) of the gastric mucosa. A marker for colorectal epithelial neoplasia? 总被引:1,自引:0,他引:1
The results of several retrospective studies allow us to conclude that the detection of fundic gland polyps (Elster's cysts) is associated with an increased incidence of colorectal tumors. In this survey, we present the results of a prospective study investigating such a possible relationship. A total of 144 patients were investigated, of whom 80 had fundic gland polyps of the gastric corpus mucosa. Sixty-four of these patients underwent a colonoscopy, whereas the other 64 patients belonged to a sex- and age-matched control group with no fundic gland polyps. In the group with known fundic gland polyps, colorectal neoplasias were found in 29 (45.3%) patients. Eight of these patients had (12.5%) adenocarcinomas, 3 (4.7%) had high-grade intraepithelial neoplasia, and 18 (28.1%) had tubular adenomas. In one patient, a synchronous carcinoma of the rectum and the colon was detected. In comparison, 6 patients of the control group (9.3%) developed tubular adenomas and 9 (14.1%) had hyperplastic polyps of the colonic and rectal mucosa. Our results suggest that it is necessary to conduct a careful diagnostic work-up of the colon in patients with gastric fundic gland polyps. 相似文献