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21.
S. A. C. DUNDAS P. MANSOUR M. ZEIDERMAN I. HARRISON P. SKIPWORTH & J. DUTTON 《Cytopathology》1997,8(4):230-235
Audit of 6 years' experience of breast fine needle aspiration (FNA) cytology using the cytospin method; improvement through multidisciplinary clinical audit
A breast FNA cytology service for palpable breast lumps was commenced in 1989 using the cytospin method. Over the following 6 years 2314 aspirates were received. The results were audited in detail in 1990, 1991/1992 and 1994. Multidisciplinary clinical audit meetings followed each audit cycle. Practice change was agreed after each audit. Each audit cycle was followed by demonstrable improvement in the complete sensitivity of the technique, being respectively 79%, 88% and 96%. The cytospin method is a viable alternative to the conventional smear method. 相似文献
A breast FNA cytology service for palpable breast lumps was commenced in 1989 using the cytospin method. Over the following 6 years 2314 aspirates were received. The results were audited in detail in 1990, 1991/1992 and 1994. Multidisciplinary clinical audit meetings followed each audit cycle. Practice change was agreed after each audit. Each audit cycle was followed by demonstrable improvement in the complete sensitivity of the technique, being respectively 79%, 88% and 96%. The cytospin method is a viable alternative to the conventional smear method. 相似文献
22.
Cervex brush versus vaginal–cervical–endocervical (VCE) triple smear techniques in cervical sampling
K JÄRVI 《Cytopathology》1997,8(4):282-288
Cervex brush versus vaginal–cervical–endocervical (VCE) triple smear techniques in cervical sampling
Cervex brush sampling was compared with the conventional triple vaginal–cervical–endocervical (VCE) smear technique. Nine hundred and fifty‐nine Cervex brush smears and 1064 VCE smears were studied. All smears with both methods were technically satisfactory for evaluation. Endocervical cells were found in 90.7% and metaplastic cells in 73.3% of Cervex brush samples and in 92.5% and 64.1% of VCE samples, respectively. There were significantly more metaplastic cells in smears from premenopausal women. Low grade squamous intraepithelial lesion (SIL) was found in three Cervex brush samples and in two VCE samples. High‐grade SIL was found only in one Cervex brush sample. Benign cellular changes were found in 142 Cervex brush samples and in 144 VCE samples. Sampling with the Cervex brush is efficient, simple and fast and gives high quality cervical smears for cytological evaluation. 相似文献
Cervex brush sampling was compared with the conventional triple vaginal–cervical–endocervical (VCE) smear technique. Nine hundred and fifty‐nine Cervex brush smears and 1064 VCE smears were studied. All smears with both methods were technically satisfactory for evaluation. Endocervical cells were found in 90.7% and metaplastic cells in 73.3% of Cervex brush samples and in 92.5% and 64.1% of VCE samples, respectively. There were significantly more metaplastic cells in smears from premenopausal women. Low grade squamous intraepithelial lesion (SIL) was found in three Cervex brush samples and in two VCE samples. High‐grade SIL was found only in one Cervex brush sample. Benign cellular changes were found in 142 Cervex brush samples and in 144 VCE samples. Sampling with the Cervex brush is efficient, simple and fast and gives high quality cervical smears for cytological evaluation. 相似文献
23.
Routine audit of breast fine needle aspiration (FNA) cytology specimens and aspirator inadequate rates 总被引:2,自引:0,他引:2
D. R. J. SNEAD P. VRYENHOEF S. E. PINDER A. EVANS A. R. M. WILSON R. W. BLAMEY C. W. ELSTON & I. O. ELLIS 《Cytopathology》1997,8(4):236-247
Routine audit of breast fine needle aspiration (FNA) cytology specimens and aspirator inadequate rates In an attempt to improve the quality of the breast FNA specimens we instigated a continuing audit of this procedure in this hospital. All FNAs since 1990 have had the following recorded: mode of aspiration, e.g. freehand or image guided, patient presentation (screening or symptomatic), patient diagnostic category, cytological diagnosis and final histological diagnosis. Aspirator performance was assessed by means of the inadequate aspiration rate (IR) of FNAs performed on patients with a final diagnosis of cancer (FDC) and diagnostic category A patients (clinically or radiologically malignant lesions). An ongoing annual review of the performance of all the aspirators was undertaken, all of whom received individual feedback. Counselling and further training were offered where indicated by poor performance. Over the period 1990–1995 a total of 13 537 FNAs were performed by 27 aspirators. The IR on category A and FDC cases over this period was 16.0% and 18.1%. The best performance achieved by an aspirator in a calendar year was an IR of 3.6% with no inadequate specimens in either FDC or category A lesions, and the best performance over the entire period was an average IR of 11.75% and 14.25% for FDC and category A groups, respectively. The overall IR on category A patients ranged from 15.9% to 23.8% and on FDC cases from 12.2% to 21.7%. There was a significant improvement in individual junior aspirator performance when their first year was compared with their last year on the unit. In some cases a deterioration in intra-aspirator performance was observed, from an IR of 6% to 33%. The overall IR rate of the unit remained stable for FDC patients, 15.5% in 1990 compared with 15.1% in 1995. This appeared to be largely due to a high proportion of the aspirations being performed by experienced personnel with consistent IRs. However, concealed within the overall rate there were some poor performers who benefited from counselling and/or further training. These results indicate an important role for audit in identifying poor aspirators who benefit from targeted training and advice, thereby improving the quality of FNA specimens, and ultimately patient care. 相似文献
24.
Fine needle aspiration (FNA) in the diagnosis of soft tissue tumours; a review of 22 years experience 总被引:1,自引:0,他引:1
FNA plays an important role in preoperative diagnosis of soft tissue tumours. A close clinical/morphologic cooperation is essential. FNA should be performed on the most accessible part of the tumour, avoiding penetration of the deep portions of the tumour. Needles 0.7 mm (22 G) are recommended. For deep lesions, needles with a stylet should be used. After the FNA, tattooing of the aspiration channel is recommended, and the channel is surgically removed together with the tumour, if a sarcoma. Material from the FNA can be used for additional examinations, i.e. electron microscopy, immunohistochemistry, DNA ploidy analysis and chromosomal analysis. Those techniques are of great importance in the differential diagnosis, particularly in the paediatric small/round cell tumours. the majority of sarcomas can be defined as low grade or high grade malignant in FNA. For malignancy grading the following parameters are used: cellularity, pleomorphism, chromatin pattern, nucleolar structure, mitotic figures and necroses. Cytodiagnostic details of the most common soft tissue tumours and their differential diagnoses are presented. 相似文献
25.
26.
T. WAYNE SCHULTZ JAMES N. DUMONT LOLA M. KYTE 《The Journal of eukaryotic microbiology》1978,25(4):502-509
SYNOPSIS. Shale oil retort water is obtained by centrifuging the oil/water emulsion produced by oil shale retorting. The ciliate Tetrahymena pyriformis was exposed to retort water; 2, 1, and 0.5% initially increased motility; longer exposures decreased motility. Three, 4, and 5% all decreased motility. Cell lysis was directly related to concentration; after 24 h, population densities were 0, 10, and 25% of controls for 2, 1, and 0.5% retort water, respectively. Oxygen consumption paralleled the motility pattern: at lower concentrations it increased initially but decreased with extended exposures while at higher concentrations it decreased rapidly. The most striking cytologic alteration of cells exposed to the toxicant occurred in the membranes; alterations of mucocysts and glycogen content were also observed, but mitochondrial changes were not. Population growth was affected at much lower concentrations than the other test indices. The growth of test populations reached a plateau at values inversely related to concentration: concentrations <0.4% had no effect on growth rate. 相似文献
27.
Summary Both the fast and slow muscle fibres of advanced teleost fish are multiply innervated. The fraction of slow-fibre volume occupied by mitochondria is 31.3%, 25.5% and 24.6%, respectively, for the myotomal muscles of brook trout (Salvelinus fontinalis), crucian carp (Carassius carassius), and plaice (Pleuronectes platessa), respectively. The corresponding figures for the fast muscles of these species are 9.3%, 4.6% and 2.0%, respectively. Cytochrome-oxidase and citrate-synthetase activities in the fast muscles of 9 species of teleost range from 0.20–0.93 moles substrate utilised, g wet weight muscle-1 min-1 (at 15° C) or around 4–17% of that of the corresponding slow fibres. Ultrastructural analyses reveal a marked heterogeneity within the fast-fibre population. For example, the fraction of fibres with <1% or >10% mitochondria is 0,4,42% and 36, 12 and 0%, respectively, for trout, carp and plaice. In general, small fibres (<500 m2) have the highest and large fibres (>1,500 m2) the lowest mitochondrial densities. The complexity of mitochondrial cristae is reduced in fast compared to slow fibres.Hexokinase activities range from 0.4–2.5 in slow and from 0.08–0.7 moles, g wet weight-1 min-1 in fast muscles, indicating a wide variation in their capacity for aerobic glucose utilisation. Phosphofructokinase activities are 1.2 to 3.6 times higher in fast than slow muscles indicating a greater glycolytic potential. Lactate dehydrogenase activities are not correlated with either the predicted anaerobic scopes for activity or the anoxic tolerances of the species studied. The results indicate a considerable variation in the aerobic capacities and principal fuels supporting activity among the fast muscles of different species. Brook trout and crucian carp are known to recruit fast fibres at low swimming speeds. For these species the aerobic potential of the fast muscle is probably sufficient to meet the energy requirements of slow swimming. 相似文献
28.
A. C. Triantaphyllou 《Journal of nematology》1991,23(2):249-253
Two tetraploid isolates of Meloidogyne hapla, 86P and E289P, with haploid chromosome numbers of 34 and 28, respectively, were studied cytogenetically and biologically in relation to the diploid populations, 86-Va (n = 17) and E289-Taiwan (n = 14), from which they had been originally isolated. Both isolates were quite stable, converting to diploidy at the low rate of about 2.5%. The tetraploid isolate 86P maintained itself in competition with its diploid counterpart in mixed cultures, although an initial frequency of 50% polyploidy was reduced to about 9% at the end of the sixth generation. Both tetraploid isolates could maintain themselves in greenhouse cultures without artificial selection for at least 2 years. Crosses between diploid females and tetraploid males resulted in a few triploid females that produced mostly nonviable eggs, suggesting partial reproductive isolation between the two ploidy forms. Ten generations of propagation of only polyploid females of isolate 86P that were associated with males failed to yield an obligatorily amphimictic isolate that would not convert at all to diploidy. If one accepts a previous assumption that the present day amphimictic root-knot nematodes are tetraploids derived from diploid ancestors, results of the present study are not inconsistent with an evolutionary trend toward an even higher level of ploidy in Meloidogyne, presumably octaploidy. 相似文献
29.
Evaluation of the Cost Effectiveness of Establishing A Fine Needle Aspiration Cytology Clinic In A Hospital Out-Patient Department 总被引:4,自引:0,他引:4
G. KOCJAN 《Cytopathology》1991,2(1):13-18
In an attempt to reduce the number of inadequate smears processed by our laboratory and the false negative rate of fine needle aspiration cytodiagnosis, we have introduced a fine needle aspiration cytology service where aspirates are taken by the cytopathologist in a clinic. In the 12 month period since the introduction of this service, the number of inadequate smears fell sharply. Nine per cent of the specimens were inadequate compared with 43% of specimens from other sources. The establishment of the clinic resulted in a threefold reduction in the cost of diagnosing breast lesions. 相似文献
30.
C. W. E. REDMAN S. E. CHAPMAN S. Y. CHAN E. J. BUXTON G. BLACKLEDGE D. M. LUESLEY† 《Cytopathology》1991,2(6):291-298
Peritoneal lavage fluid cytology was performed in 87 out-patients with histologically proven epithelial ovarian cancer undergoing primary management. A total of 246 peritoneal lavages were attempted, usually with temporary cannulae (n = 229). From these, 184 samples were obtained, of which 156 (85%) were suitable for cytological analysis. The sensitivity of peritoneal lavage fluid cytology in 67 patients with known residual disease was 57% whereas serum CA 125 levels were elevated in 58 (87%). Pre- and post-treatment peritoneal lavage fluid cytology had prognostic value, but this was less than that of serum CA 125 measurements. 相似文献