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1.
Cytochemistry     
L G Koss 《Acta cytologica》1984,28(4):353-355
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2.
Measurements of nuclear DNA were performed in urothelial cells in 54 Feulgen-restained cytocentrifuge preparations of voided urine previously studied visually and with an image analysis system. The study included 30 patients with bladder tumors of various grades, 9 patients with prostatic disease and 15 control samples from normal donors. A number of additional control measurements were performed, including measurements in tissue samples of the 30 bladder tumors corresponding to the cytologic samples. It was documented that DNA can be measured in most urinary sediments. The diagnostic performance of the image analysis system reflected the DNA patterns in 47 of the 54 cases. In several instances, particularly in cases of prostatic disease, the image analysis system recognized abnormal DNA patterns in the absence of significant morphologic abnormalities in the urothelial cells. In seven cases, the image analysis findings failed to conform with the DNA patterns. The reasons for these surprising results are discussed, and future modifications of the image analysis system are proposed.  相似文献   
3.
A Bladder Cancer Flow Cytometry Network study has been carried out aimed at identification of the sources of inter- and intralaboratory variability. Replicate "cocktail" samples containing a mixture of peripheral blood lymphocytes and an aneuploid cell line and samples of peripheral blood lymphocytes serving as a DNA reference standard were distributed to five network laboratories. The samples were stained for DNA using propidium iodide, with each laboratory using its own staining protocol. Sets of these samples were analyzed by flow cytometry to obtain cellular DNA distributions. DNA index and hyperdiploid fraction were calculated for each histogram using an automated technique. Results were evaluated by analysis of variance to identify sources of variability. Three important sources of variation were found that affect flow cytometry in general and- the transportability of flow cytometry results to routine clinical use in particular. The significant variation among laboratories that is constant across time most probably represents stable differences in instrumentation, instrument set-up, and laboratory techniques. This variation can be compensated for, if it is known and stable, to develop transportable classification criteria. The second type of variation, termed the interaction component, represents differences among laboratories that are not constant across time. Sources of this variation include inconsistency in sample preparation, staining, and analysis. The elimination of this type of variation is required for meaningful comparison of data within and among laboratories and the creation of interlaboratory data-bases. The third type of variation represents pure measurement variability and affects the sensitivity of the technique.  相似文献   
4.
Summary Two pairs of ganglia are found in the propodial region of the veliger of Onchidoris bilamellata: the anterolateral pair is located at the foremost corners of the propodium, and the frontal pair is located beside the propodial midline. Both sets of ganglia are positioned below the epidermis, and they are joined to the cerebral ganglia by large, common connectives. Each ganglion possesses sensory cells, nerve cells and sheath cells, and the frontal pair contains a complement of secretory cells. Externally, the propodial ganglia are manifested as sensory fields. The fields of the anterolateral pair are elliptical in shape, and each appears as a band of cilia bordering an unciliated zone. The region devoid of cilia is composed of ordinary epidermal cells, whereas the ciliated portion is comprised of dendritic endings originating from cells in the ganglion. Dendrites arise from one type of sensory cell and pass through the epidermis in bundles. Each dendrite terminates as a single cilium at the epidermal surface. Sensory fields of the frontal ganglia are key-shaped and oppose one another on the anterior end of the foot. Each field appears as a flat, circular, unciliated region which extends into a ciliated groove that runs dorsally toward the mouth. The groove contains the terminals of secretory cells, ciliated sensory cells, and the cell bodies of nonciliated sensory cells. The nonciliated sensory cells, characterized by a microvillous apex, are the dominant cells in the flattened circular zone. The space between the frontal ganglia and the epidermis is bridged by bundles of processes which are similar to those of the anterolateral ganglia. However, these tracts contain collections of the apical processes of secretory cells, the dendrites of ciliated sensory cells, and the axons of nonciliated sensory cells. Morphological and behavioral evidence indicates that the propodial ganglia serve a chemosensory function during settlement and metamorphosis.  相似文献   
5.
As part of an ongoing study of objective parameters of prognostic value in prostatic carcinoma, a routine procedure was developed to aspirate all prostates prior to surgery. These targets were different from those of other workers in the field of prostatic fine needle aspiration (FNA), who generally advocate that FNA be confined to suspicious nodules. The aspirations were performed by a large group of practicing urologists who had no special training in prostatic FNA except for guidelines provided by their peers and information available in the literature. This approach permitted an assessment of the performance of FNA as a screening test rather than as a diagnostic procedure. During the period from January 1983 to February 1987, 1,683 patients had prostatic FNAs performed (plus subsequent histologic study). The following diagnoses were rendered: "inadequate/scanty specimen" in 625 cases (37%), "negative/atypical" in 844 cases (50%) and "suspicious/positive" in 214 cases (13%). Histologic examination showed stage A1 prostatic adenocarcinoma in 18 patients. The cytologic diagnoses on these 18 patients were inadequate/scanty in 3 (17%), negative/atypical in 13 (72%) and suspicious/positive in 2 (11%). Of the 214 patients with a positive/suspicious diagnosis by FNA, the diagnosis of prostatic carcinoma was confirmed by tissue evidence in 200; the other 14 patients had either no evidence of prostatic carcinoma on surgical biopsy (needle biopsy/transurethral resection/suprapubic prostatectomy) or had no surgical biopsy. Eight of the 14 patients developed clinical evidence of carcinoma, 1 died of urinary bladder carcinoma and 1 was lost to follow-up. In the remaining four patients, there is still no evidence of prostatic carcinoma after about one-and-one-half years of follow-up. These results indicate that (1) specialized training is required in order to obtain adequate smears by prostatic FNA; (2) prostatic FNA is not a good screening technique for detecting stage A1 prostatic carcinoma; and (3) a positive diagnosis by prostatic FNA, even when not confirmed by tissue biopsy, is still an indication of disease.  相似文献   
6.
A video-based computerized semiautomated image analysis system was applied to the diagnostic evaluation of 119 sediments of voided urine: 103 from patients with a broad variety of neoplastic and nonneoplastic disorders of the lower urinary tract and 16 normal controls. Each specimen was presented to the machine as a single cytocentrifuge preparation, preserved in 2% Carbowax in 50% ethanol and stained-by the Papanicolaou method. Five hundred sequential "objects" were scanned within an area of 9 sq mm on each slide. "Objects" of no diagnostic value, such as dirt, debris, inflammatory cells, cell clusters, poorly preserved cells, etc., were eliminated from the final diagnostic analysis by a computer-based hierarchic triage system. The final specimen classifier was based on the cell images identified by the computer as well-preserved normal (NEG), atypical (ATY I), suspicious (ATY II) and malignant (POS) cells. For specimen classification by computer, the four categories of "abnormal," "inadequate," "acellular" and "negative" were defined. For high-grade tumors, the performance of the specimen classifier was generally comparable to the visual diagnosis. The specimen classifier unexpectedly identified twice as many low-grade papillary urothelial tumors as abnormal than did the visual analysis. Several false "alarms" were recorded by computer in patients with benign prostatic hypertrophy and prostatic carcinoma, some of whom had atypical urothelium. One of the 16 negative controls was misdiagnosed by the computer as abnormal. The possibility that the video system recognizes nuclear abnormalities not perceived by the human eye is being investigated further. The details of the computer analysis are reported, and the value of the system is discussed. The system appears to be promising as a future laboratory instrument, although it requires further extensive testing.  相似文献   
7.
A study was undertaken to demonstrate the safety, efficacy and value of esophageal balloon cytology in the diagnosis of esophageal lesions and as a tool in screening a high-risk patient population. The sampling was performed 110 times on 96 patients, 11 with known obstructive carcinoma of the esophagus and 85 thought to be at risk for esophageal cancer: 74 with treated or untreated cancer of the head and neck area and 11 with dysphagia or other findings requiring clarification. The method was well tolerated by the patients, and the cytologic smears were of excellent quality. Malignant or suspicious cells were found in smears from 7 to 11 patients with documented esophageal cancer and in 7 of 85 patients believed to be at risk. In the latter group there were three unsuspected recurrent cancers of the oropharyngeal region and one unsuspected carcinoma in situ of the esophagus. There were no false-suspicious or false-positive results. This noninvasive technique of esophageal cytology obviously deserves additional trials as an adjunct in the diagnosis of carcinoma of the head and neck and upper gastrointestinal tract, especially in high-risk patients.  相似文献   
8.
Cortical granules, which are specialized secretory organelles found in ova of many organisms, have been isolated from the eggs of the sea urchins Arbacia punctulata and Strongylocentrtus pupuratus by a simple, rapid procedure. Electron micropscope examination of cortical granules prepared by this procedure reveals that they are tightly attached to large segments of the plasma membrane and its associated vitelline layer. Further evidence that he cortical granules were associated with these cell surface layers was obtained by (125)I-labeling techniques. The cortical granule preparations were found to be rich in proteoesterase, which was purified 32-fold over that detected in a crude homogenate. Similarly, the specific radioactivity of a (125)I-labeled, surface glycoprotein was increased 40-fold. These facts, coupled with electron microscope observations, indicate the isolation procedure yields a preparation in which both the cortical granules and the plasma membrane-vitelline layer are purified to the same extent. Gel electrophoresis of the membrane-associated cortical granule preparation reveals the presence of at least eight polypeptides. The major polypeptide, which is a glycotprotein of apparent mol wt of 100,000, contains most of the radioactivity introduced by (125)I-labeling of the intact eggs. Lysis of the cortical granules is observed under hypotonic conditions, or under isotonic conditions if Ca(2+) ion is present. When lysis is under isotonic conditions is induced by addition of Ca(2+) ion, the electron-dense contents of the granules remain insoluble. In contrast, hypotonic lysis results in release of the contents of the granule in a soluble form. However, in both cases the (125)I-labeled glycoprotein remains insoluble, presumably because it is a component of either the plasma membrane or the vitelline layer. All these findings indicate that, using this purified preparation, it should be possible to carry out in vitro studies to better define some of the initial, surface-related events observed in vivo upon fertilization.  相似文献   
9.
Summary The two statocysts of the veliger larva of Rostanga pulchra are positioned within the base of the foot. They are spherical, fluid-filled capsule that contain a large, calcareous statolith and several smaller concretions. The epithelium of the statocyst is composed of 10 ciliated sensory cells (hair cells) and 11 accessory cells. The latter group stains darkly and includes 2 microvillous cells, 7 supporting cells, and 2 glial cells. The hair cells stain lightly and each gives rise to an axon; two types can be distinguished. The first type, in which a minimum of 3 cilia are randomly positioned on the apical cell membrane, is restricted to the upper portion of the statocyst. The second type, in which 9 to 11 cilia are arranged in a slightly curved row, is found exclusively around the base of the statocyst. Each statocyst is connected dorso-laterally to the ipsilateral cerebral ganglion by a short static nerve, formed by axons arising from the hair cells. Ganglionic neurons synapse with these axons as the static nerve enters the cerebral ganglion. The lumen of the statocyst is continuous with a blind constricted canal located beneath the static nerve.A diagram showing the structure of the statocyst and its association with the nervous system is presented. Possible functions of the statocyst in relation to larval behavior are discussed.  相似文献   
10.
Twelve patients with inactive ulcer disease were administered placebo and ranitidine via bolus and continuous intravenous infusions, at doses ranging from 50 every 8 h, to 12.5 mg/h for 24 h. Gastric acid was collected for 20 min each h for 24 h, and ranitidine serum concentrations were measured ± every 2 h, during each of the six study periods. Cosinor analysis of gastric acid secretion during placebo treatment revealed a significant circadian rhythm in all subjects. Mesor acid output ranged from 1.7 to 11.6 mmol/h (mean 5.6 ± 2.8 mmol/h) and the amplitude ranged from 0.7 to 6.5 mmol/h (mean 2.8 ±1.6 mmol/h). Peak acid output (acrophase) occurred at 10 p.m. ± 3 h. A pharmacodynamic model, relating ranitidine serum concentration to hourly acid secretion, was derived, which incorporated the circadian change in basal acid output. Data for this fractional response model included basal acid secretion-as determined by time of day, measured acid secretion, and associated serum ranitidine concentration. The 50% inhibitory concentration (IC50) for ranitidine ranged from 10-75 ng/ml, with a mean of 44 ng/ml. The variation in IC50 and in basal acid secretion combined to produce a wide variation in the pharmacodynamic response to ranitidine. The model-predicted serum concentrations, required to maintain acid secretion at 0.1 mmol/h, ranged from 250 to 1550 ng/ml, at the time of peak evening acid secretion. Despite a constant degree of acid inhibition by ranitidine during the day, higher serum concentrations are required during times of peak acid output to maintain adequate suppression of hydrogen ion secretion.  相似文献   
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