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101.
Pre-B cells and other possible precursor lymphoid cell lines derived from patients with X-linked agammaglobulinemia 总被引:14,自引:6,他引:14 下载免费PDF全文
SM Fu JN Hurley JM McCune HG Kunkel RA Good 《The Journal of experimental medicine》1980,152(6):1519-1526
A group of unique Epstein-Barr virus-containing cell lines was derived from the bone marrow of three patients with X-linked agammaglobulinemia. Efforts to obtain cell lines from the peripheral blood of these patients were uniformly unsuccessful. Immunofluorescence analyses as well as biosynthetic studies with [(35)S]methionine indicated unusual patterns of Ig synthesis in many of these bone marrow derived lines. Seven of the lines were of particular interest in that two produced no Ig of any type; two others showed no Ig by fluorescence but small amounts by [(35)S]methionine labeling; one expressed only cytoplasmic μ chains without any evidence of light chain synthesis, and two produced primarily μ chains with only slight amounts of light chains. One of the lines without membrane or cytoplasmic Ig studied in detail grew like a typical lymphoid line and was carried in intermittent culture over a period of 2 yr without Ig expression. One line grew quite differently and resembled the round cell type described previously, which has been obtained from a variety of sources. The cell line with cytoplasmic μ chains and no light-chain expression had the characteristic properties of pre-B cells. Three normal type Ig-producing cell lines also were obtained from the patients. The accumulated evidence obtained in the present study indicates that these unusual cell lines represent normal precursor cells of the B-cell lineage; these grew out in these cases because of the virtual absence of mature B cells that ordinarily overgrow the culture system. However, the possibility that in certain instances they reflect abnormal Ig synthesis characteristic of the disease has not been ruled out. 相似文献
102.
Monitoring for undertransfusion 总被引:1,自引:0,他引:1
BACKGROUND: Most published reviews and audits of blood and blood component transfusion have focused on the issue of overtransfusion and on the inappropriate use of red cell components. There is growing concern that efforts to curb unnecessary transfusions may result in a trend toward undertransfusion of patients. There is little published information that addresses this issue or the magnitude of this practice. STUDY DESIGN AND METHODS: Undertransfusion was evaluated by examining the transfusion records from a 3-month period for 55 patients who met the study criteria of having either a hemoglobin level < 7 g per dL or a platelet count of < 10 × 10(9) per L. If the identified patient did not receive a transfusion within 24 hours of the reported hemoglobin level or platelet count, the medical record was reviewed by a resident physician. RESULTS: A total of 213 individual hemoglobin levels and platelet counts, representing the 55 patients, met our transfusion criteria. All except 8 of the identified patients received red cells and/or platelet transfusions. Reasons for not transfusing red cells included the patient's response to nutritional support and iron supplementation, refusal of blood, and noncompliance. Reasons for not transfusing platelets included falsely low platelet count because of platelet clumping in vitro, contraindication based on clinical diagnosis (e.g., immune thrombocytopenic purpura), and the patient's death before transfusion. CONCLUSION: Red cell and platelet transfusions were appropriately ordered for all patients who met the transfusion criteria. Undertransfusion is not a problem at this institution according to the criteria established. It is recommended that other institutions expand their blood utilization audits to include investigation for evidence of undertransfusion. Further research regarding the issue of undertransfusion is warranted and could be expanded to include other components. 相似文献
103.
Seaton RA; Naraqi S; Wembri JP; Warrell DA 《QJM : monthly journal of the Association of Physicians》1996,89(6):423-428
In Papua New Guinea, <it>Cryptococcus neoformans</it> var.
<it>gattii</it> meningitis has a high fatality rate even in
immunocompetent patients. Our retrospective study attempted to identify
marker of poor prognosis. Of 88 immunocompetent patients, 30 (34.1%) died,
usually soon after admission, and mortality was higher in men
(<it>p</it> = 0.025) and older patients (<it>p</it>
= 0.039). Death was associated with altered consciousness
(<it>p</it><0.001), a history of convulsions prior to
treatment (<it>p</it> = 0.002) and a maximum systolic blood
pressure of >150 mmHg (<it>p</it> = 0.017). These data
suggest that death results from raised intracranial pressure and subsequent
tentorial herniation. However, CSF opening pressure measured on admission
was raised in 29/36 (81%) patients and did not predict outcome. In
survivors, relapse was uncommon and was not predicted by discharge serum
cryptococcal antigen titres, which were frequently raised on completion of
therapy in asymptomatic patients. Mortality may be reduced if efforts are
made to lower intracranial pressure in those patients who present with
markers of poor prognosis.
相似文献
104.
Familial hemiplegic migraine: a clinical comparison of families linked and unlinked to chromosome 19 总被引:5,自引:0,他引:5
GM Terwindt RA Ophoff J Haan RR Frants MD Ferrari for the DMGRG 《Cephalalgia : an international journal of headache》1996,16(3):153-155
We compared the clinical characteristics of 50 patients from three unrelated families with familial hemiplegic migraine (FHM) linked to chromosome 19, with those of 20 patients from two families with FHM not linked to chromosome 19. We found no significant differences for age at onset, frequency and duration of attacks, duration of the paresis, and occurrence of basilar migraine symptoms. In the linked families, significantly more patients reported unconsciousness during attacks (39%, vs 15%; p<0.05) and provocation of attacks by mild head trauma (70% vs 40%; p< 0.05). In one linked family patients also displayed chronic progressive cerebellar ataxia, whereas in one unlinked family benign infantile convulsions occurred in addition to FHM. Interestingly, so far an association with cerebellar ataxia was only described in chromosome 19-linked families. FHM linked to chromosome 19 and FHM unlinked to chromosome 19 do not differ with respect to clinical features. 相似文献
105.
106.
Lynn J. White MS Jeffrey S. Jones MD Christopher W Felton MD Linda C. Pool RA 《Academic emergency medicine》1996,3(8):745-750
Objective: To identify common discrepancies and average reading grade levels for informed consent forms (ICFs) us submitted to institutional review boards (IRBs) by medical researchers.
Methods: A retrospective evaluation of ICFs as submitted to IRBs of 3 university-affiliated hospitals during a I-year period. ICF content was evaluated using a checklist of 23 requirements specified in the federal regulations governing human research. Documents then were computer-analyzed to determine the readability scores using 2 common indexes of comprehension. A discrepancy was defined as any instance in which an ICF did not address an applicable requirement in the Code of Federal Regulations.
Results: Eighty-two ICFs representing 16 medical specialties were evaluated; 8 (10%) were from emergency medicine. Eighteen ICFs (22%) were conspicuously incomplete, lacking 29 federal requirements. The mean number of discrepancies was 4.7 (95% CI, 3.9–5.5) Common omissions included: a statement about who is doing the research, number of subjects in the study, circumstances when a subject's participation may be terminated, disclosure of alternative procedures, and notice to subjects regarding new findings. The mean Flesch grade level required to read all ICFs was 13.8 (95% CI, 13.5–14.2), implying that the majority of the U.S. adult population would be unable to comprehend these forms.
Conclusion: Designing a consent form to meet all of the federal requirements while maintaining a level of reading comprehension suitable for the general population is a difficult task for investigators. 相似文献
Methods: A retrospective evaluation of ICFs as submitted to IRBs of 3 university-affiliated hospitals during a I-year period. ICF content was evaluated using a checklist of 23 requirements specified in the federal regulations governing human research. Documents then were computer-analyzed to determine the readability scores using 2 common indexes of comprehension. A discrepancy was defined as any instance in which an ICF did not address an applicable requirement in the Code of Federal Regulations.
Results: Eighty-two ICFs representing 16 medical specialties were evaluated; 8 (10%) were from emergency medicine. Eighteen ICFs (22%) were conspicuously incomplete, lacking 29 federal requirements. The mean number of discrepancies was 4.7 (95% CI, 3.9–5.5) Common omissions included: a statement about who is doing the research, number of subjects in the study, circumstances when a subject's participation may be terminated, disclosure of alternative procedures, and notice to subjects regarding new findings. The mean Flesch grade level required to read all ICFs was 13.8 (95% CI, 13.5–14.2), implying that the majority of the U.S. adult population would be unable to comprehend these forms.
Conclusion: Designing a consent form to meet all of the federal requirements while maintaining a level of reading comprehension suitable for the general population is a difficult task for investigators. 相似文献
107.
Intra-articular Chlamydial Antigen and Inflammatory Arthritis 总被引:1,自引:0,他引:1
HUGHES RA; HYDER E; TREHARNE JD; KEAT ACS 《QJM : monthly journal of the Association of Physicians》1991,80(1):575-588
Joint material from 133 patients with well-characterized inflammatoryarthritis, including individuals likely to have suffered reactivearthiritis, was studied. The majority of patients were alsoexamined for the presence of genital tract infection with Chlamydiatrachomatis. Fluorescein-conjugated monoclonal antibodies demonstratedthe presence of C. trachomatis antigen in synovial fluid celldeposits or synovial sections from inflamed knee joints of sevenpatients with reactive arthritis. The significance of thesefindings is discussed, as is the low rate of detection of chlamydialantigen in either the genital tract or the joint from patientsin this study. We emphasize the need for further work aimedat identifying the relevant immunogenic chlamydial antigensresponsible for the initiation of reactive arthritis. 相似文献
108.
Oral cyclophosphamide versus chlorambucil in the treatment of patients with membranous nephropathy and renal insufficiency 总被引:4,自引:1,他引:4
Branten AJ; Reichert LJ; Koene RA; Wetzels JF 《QJM : monthly journal of the Association of Physicians》1998,91(5):359-366
We treated patients with idiopathic membranous nephropathy (iMGN) and renal
insufficiency, using: (i) (n = 15) monthly cycles of steroids (1 g
methyl-prednisolone i.v. on three consecutive days, followed by oral
prednisone 0.5 mg/kg/day months 1, 3 and 5) and chlorambucil (0.15
mg/kg/day months 2, 4 and 6); or (ii) (n = 17) oral cyclophosphamide
(1.5-2.0 mg/kg/day for 1 year) and steroids in a comparable dose. The
groups were comparable in age, renal function and levels of proteinuria.
During the 6 months preceding treatment, serum creatinine levels increased
from 148 +/- 50 to 219 +/- 73 mumol/l in the chlorambucil group and from
164 +/- 86 to 274 +/- 126 mumol/l in the cyclophosphamide group. Median
(range) follow-ups were: chlorambucil 38 months (8-71); cyclophosphamide 26
months (5-68) (NS). Renal function improved in both groups, but the
improvement was short-lived in the chlorambucil group; 12 months after
starting treatment, mean serum creatinine was 6.3 mumol/l lower in the
chlorambucil group and 121 mumol/l lower in the cyclophosphamide group (p
< 0.01). Four chlorambucil-treated patients developed ESRD, and five
needed a second course of therapy, whereas only one
cyclophosphamide-treated patient developed ESRD (p < 0.05). Remissions
of proteinuria occurred more frequently after cyclophosphamide treatment
(15/17 vs. 5/15; p < 0.01). Side-effects necessitated interruption of
treatment in six patients on cyclophosphamide and in 11 on chlorambucil (p
< 0.05). In our patients, oral cyclophosphamide was better tolerated
than oral chlorambucil. The suggested greater efficacy of the oral
cyclophosphamide regimen needs to be ascertained by longer follow-up.
相似文献
109.
SR Kulkarni MS Gohel RA Bulbulia MR Whyman KR Poskitt 《Annals of the Royal College of Surgeons of England》2009,91(3):210-213
INTRODUCTION
Early carotid endarterectomy (CEA) in symptomatic patients may prevent repeat cerebral events. This study investigates the relationship between waiting time for CEA and the incidence of repeat cerebral events prior to surgery in symptomatic patients.PATIENTS AND METHODS
A prospective database of consecutive patients undergoing CEA between January 2002 and December 2006 was reviewed. Repeat event rates prior to surgery were calculated using Kaplan–Meier analysis and predictive factors identified using Cox regression analysis.RESULTS
A total of 118 patients underwent CEA for non-disabling stroke, TIA and amaurosis fugax. Repeat cerebral events occurred in 34 of 118 (29%) patients at a median 51 days (range, 2–360 days) after the first event. The estimated risk of repeat events was 2% at 7 days and 9% at 1 month after first event (Kaplan–Meier survival analysis). Age (HR 1.059; 95% CI 1.014–1.106; P = 0.009] was identified as a predictor of repeat events. Patients underwent surgery at median 97 days (range, 7–621 days) after the first event. Eleven of 60 (18%) patients waiting ≤?97 days for surgery and 23 of 58 (40%) patients waiting >?97 days had repeat events. (P = 0.011, chi-squared test).CONCLUSIONS
Delays in surgery should be reduced in order to minimise repeat cerebral events in patients with symptomatic carotid stenosis, particularly in the elderly population. 相似文献110.
RA Pearl W Townley D Stott AO Grobbelaar 《Annals of the Royal College of Surgeons of England》2009,91(6):494-499