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1.
Paediatric dacryocystorhinostomy 总被引:1,自引:0,他引:1
KN Hakin FRCS FRCOphth TJ Sullivan FRACO FRACS A Sharma FCOphth † RAN Welham FRCS FCOphth † 《Clinical & experimental ophthalmology》1994,22(4):231-235
Of 258 cases of dacryocystorhinostomy performed on children in the period September 1981 to September 1991, 130 were for simple, unresolved congenital nasolacrimal duct obstruction. Other indications for surgery included punctal agenesis, lacrimal fistula, post-traumatic and post-inflammatory canalicular obstruction. Of 177 children without canalicular pathology, 171 (96%) were relieved of symptoms with one operation, without canalicular intubation. Of 81 cases with canalicular disease, 55 of 70 (79%) who underwent DCR plus canalicular intubation, and 10 of 11 who underwent DCR plus Lester-Jones tube, were substantially improved with one operation. No child required peroperative or postoperative blood transfusion. Dacryocystorhinostomy in childhood, in experienced surgical hands, is a safe procedure, achieving relief of symptoms in most cases, particularly in the absence of canalicular disease. 相似文献
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Chang HJ Batts KP Lloyd RV Sebo TJ Thompson GB Lohse CM Pankratz SV 《Endocrine pathology》2000,11(3):229-241
Nonfunctioning islet cell tumors or pancreatic endocrine tumors are the most common type of malignant islet cell tumor. Although
previously detected usually at an advanced stage because of mass effect, the early detection rate of small localized disease
has been increasing. To date it has been difficult to predict the clinical behavior in localized regional nonfunctioning tumors.
To investigate potential markers predicting malignancy and poor prognosis in nonfunctioning pancreatic endocrine tumors, we
analyzed the expression of Ki-67, topoisomerase IIα (Topollα), and p27, as well as a variety of clinicopathologic parameters
in 76 cases of nonfunctioning islet cell tumors (23 benign cases and 53 malignant cases). Ki-67, Topollα, and p27 labeling
indices were significantly different between benign and malignant tumors. Expression of Ki-67, Topollα, and p27 were associated
with survival in patients with a malignant tumor in a univariate setting. However, only p27 and Topollα were jointly associated
with survival in multivariate analysis. Immunohistochemical staining for p27, Topollα, and Ki-67 can be helpful in the diagnosis
of nonfunctioning pancreatic endocrine tumor. Analysis of p27 and Topollα may also have potential utility as prognostic factors
for malignant tumors. 相似文献
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Predominance of null mutations in ataxia-telangiectasia 总被引:15,自引:4,他引:15
Gilad S; Khosravi R; Shkedy D; Uziel T; Ziv Y; Savitsky K; Rotman G; Smith S; Chessa L; Jorgensen TJ; Harnik R; Frydman M; Sanal O; Portnoi S; Goldwicz Z; Jaspers NG; Gatti RA; Lenoir G; Lavin MF; Tatsumi K; Wegner RD; Shiloh Y; Bar-Shira A 《Human molecular genetics》1996,5(4):433-439
Ataxia-telangiectasia (A-T) is an autosomal recessive disorder involving
cerebellar degeneration, immunodeficiency, chromosomal instability,
radiosensitivity and cancer predisposition. The responsible gene, ATM, was
recently identified by positional cloning and found to encode a putative
350 kDa protein with a Pl 3-kinase-like domain, presumably involved in
mediating cell cycle arrest in response to radiation-induced DNA damage.
The nature and location of A-T mutations should provide insight into the
function of the ATM protein and the molecular basis of this pleiotropic
disease. Of 44 A-T mutations identified by us to date, 39 (89%) are
expected to inactivate the ATM protein by truncating it, by abolishing
correct initiation or termination of translation, or by deleting large
segments. Additional mutations are four smaller in-frame deletions and
insertions, and one substitution of a highly conserved amino acid at the Pl
3-kinase domain. The emerging profile of mutations causing A-T is thus
dominated by those expected to completely inactivate the ATM protein. ATM
mutations with milder effects may result in phenotypes related, but not
identical, to A-T.
相似文献
10.
Extraskeletal myxoid chondrosarcoma: a clinicopathologic, immunohistochemical, and ploidy analysis of 23 cases. 总被引:3,自引:0,他引:3
A M Oliveira T J Sebo J E McGrory T A Gaffey M G Rock A G Nascimento 《Modern pathology》2000,13(8):900-908
Twenty-three cases of extraskeletal myxoid chondrosarcoma, evaluated at the Mayo Clinic between 1968 and 1996, were studied for clinicopathologic features, immunohistochemical profile, Ki-67 activity, and ploidy status to identify adverse prognostic factors. Females and males were equally affected, and the median age at diagnosis was 50 years. The tumors were located mainly in the lower extremities (83%), and the median tumor size was 9.5 cm. Sixteen tumors showed low cellularity (70%), and eight tumors had high mitotic activity (more than two per 10 high-power fields). The tumors were immunoreactive for vimentin (89%), synaptophysin (72%), epithelial membrane antigen (28%), and S-100 protein (17%). Nine tumors were diploid, three aneuploid, and one tetraploid. Mean Ki-67 activity was 11% (range, 1 to 45%). The 10-year overall survival rate was 78%. On univariate analysis, tumor size > or = 10 cm, high cellularity, presence of anaplasia or rhabdoid features, mitotic activity more than two per 10 high-power fields, Ki-67 > or = 10%, and Ki-67 "hot spot" > or = 25% were associated with decreased metastasis-free or overall survival. Ploidy status was not associated with any adverse outcome. The presence of any of these adverse prognostic factors can indicate the possibility of a more aggressive behavior in extraskeletal myxoid chondrosarcoma, and a closer follow-up is suggested. 相似文献