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卢日刚 《药学学报》1992,27(11):871-874
This paper provides a basic principle and experimental technique of derivative signal multiplier spectrophotometry in multicomponent mixture. A microcomputer was used to process the spectral data measured on a manual spectrophotometer (UV-7520) for the determination of moroxydine hydrochloride in Gan Mao Qing capsules. Quantitative analysis of multicomponent mixture can be done without sample separation. The selection of optimal wavelength pairs is performed through the program with a computer. The method needs no special spectrophotometer and is simple, rapid and easy to operate. The mean recovery was 99.98 +/- 0.53% (n = 12).  相似文献   
3.
An original approach to the measurement of analytes in clinical chemistry has now become available, in which dry reagent strip technology is linked to measurement by reflectance spectroscopy. The present studies have evaluated the performance of the first of these test systems—for uric acid, urea and glucose, in serum—by comparison with conventional liquid chemistry methods. Satisfactory performance in terms of both precision and accuracy was obtained for all three test systems, the current “state-of-the-art” performance criteria being met; the Seralyzer system proved reliable and easy to use in the hands of trained operators. It should find a place as a “Stat” analyser in the laboratory, in specified wards and in Health Centres.  相似文献   
4.
Localization and induced expression of fusion genes in the rat lung.   总被引:5,自引:0,他引:5  
Liposome-mediated gene transfer is useful for DNA transfection into cells in culture. We wondered whether this method could be used to introduce new DNA into the intact lung. Fusion genes containing either the Rous sarcoma virus (RSV) promoter or the mouse mammary tumor virus (MMTV) promoter (which contains glucocorticoid response elements) were linked to the bacterial gene chloramphenicol acetyltransferase (CAT), an enzyme not present in mammalian cells. Plasmids containing the RSV-CAT fusion gene were mixed with cationic liposomes (Lipofectin; BRL, Inc., Grand Island, NY), and single doses were instilled into the cervical trachea of anesthetized rats. Control rats received either liposomes or plasmid. After 24, 48, and 72 h, lungs were perfused free of blood, homogenized, and analyzed for CAT enzyme activity. Liver and kidney tissue were also obtained. We found that rats given either intratracheal liposomes or plasmid had no detectable CAT activity. By contrast, 24 h after instillation of lipid:DNA complexes, lung CAT expression remained elevated for the next 48 h but was barely detectable in liver or kidney. In another group of rats, MMTV-CAT:liposome complexes were instilled intratracheally and then the rats were injected with either dexamethasone or saline. We found that the dexamethasone-treated rats had a 5- to 10-fold higher level of lung CAT expression at 24 and 48 h than the saline-treated controls had; liver and kidney CAT levels were negligible in both groups. Dexamethasone treatment did not increase RSV-CAT expression, indicating that the dexamethasone effect on MMTV-CAT expression was related to the presence of the MMTV promoter.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
5.
OBJECTIVE: Because the survival rate has increased for extremely low birth weight neonates, many have raised the concern that the rate of developmental disability among survivors will also increase. To address this concern, we analyzed changes over time in survival and major neurosensory impairment in a sample of extremely low birth weight infants born between July 1, 1979, and June 30, 1994. METHODS: The study sample included 513 infants with birth weights of 501 to 800 g who were cared for in either of the two neonatal intensive care units that serve a 17-county region in northwest North Carolina and who were born to mothers residing in that region. At 1 year of age (corrected for gestation), survivors were examined by a pediatrician and were tested using the Bayley Scales of Infant Development. Major neurosensory impairment was defined as cerebral palsy, a Bayley Mental Developmental Index <68, or blindness. A total of 209/216 (97%) of survivors were examined at 1 year of age. Epoch of birth was defined as follows: epoch 1, July 1, 1979 to June 30, 1984; epoch 2, July 1, 1984 to June 30, 1989; and epoch 3, July 1, 1989 to June 30, 1994. RESULTS: Survival rates for epochs 1, 2, and 3 were, respectively, 24/120 (20%), 63/175 (36%), and 129/218 (59%). In contrast, the proportions with a major neurosensory impairment did not increase over time; rates for successive epochs were 6/24 (25%), 17/61 (28%), and 26/124 (21%). Rates of cerebral palsy were 3/24 (13%), 12/61 (20%), and 9/124 (7%); rates of delayed mental development were 4/24 (17%), 12/61 (20%), and 17/124 (14%); and rates of blindness were 2/24 (8%), 0/62, and 5/124 (4%), respectively. CONCLUSIONS: This analysis suggests that the increasing survival of extremely low birth weight neonates since the late 1970s has not resulted in an increased rate of major developmental problems identifiable at 1 year of age.  相似文献   
6.
PURPOSE: To determine the maximum-tolerated dose (MTD) of concurrent systemic oxaliplatin (Oxal) combinations plus hepatic arterial infusion (HAI) in patients with unresectable hepatic metastases from colorectal cancer. PATIENTS AND METHODS: Thirty-six patients (89% previously treated) with unresectable liver metastases were treated with concurrent HAI and systemic Oxal plus irinotecan (CPT-11; group A) or Oxal, fluorouracil (FU), and leucovorin (LV; group B). Systemic chemotherapy was administered every 2 weeks concurrent with 2 weeks of HAI floxuridine (FUDR) and dexamethasone (Dex) every 28 days. RESULTS: The MTD for patients in group A was Oxal 100 mg/m(2), CPT-11 150 mg/m(2), and FUDR 0.12 mg/kg x 30 mL divided by pump flow rate. The MTD for group B was Oxal 100 mg/m(2), LV 400 mg/m(2), and FU 1,400 mg/m(2) by continuous infusion over 48 hours, with the same FUDR dose as in group A. Grade 3 or 4 toxicities in groups A and B included diarrhea (24% and 20%), neutropenia (10% and 7%), neurotoxicity (24% and 20%), and bilirubin more than 3 mg/mL (5% and 7%, respectively). The complete and partial response rate totaled 90% for group A and 87% for group B. Median survival time was 36 and 22 months for groups A and B, respectively. Seven patients in group A were ultimately able to undergo liver resection. CONCLUSION: Combination therapy with HAI FUDR and Dex plus systemic Oxal combinations may be safely administered to patients with colorectal cancer. The high response rate (88%) and the possibility of conversion to resectability, despite disease progression on prior systemic regimens, suggest that these combinations should be evaluated in larger studies as first- or second-line therapy in patients with hepatic metastases from colorectal cancer.  相似文献   
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8.
We have investigated the localization of thrombospondin (TSP), fibrinogen, fibronectin, and von Willebrand factor in human platelets by transmission electron microscopy of antibody-stained ultrathin frozen sections. In negatively stained thin sections, alpha granules were identified on the basis of their smooth, roughly spherical shape, size, single limiting electron-lucent 100 A membrane, and frequent presence of electron-dense nucleoid. In contrast, mitochondria exhibited characteristic double membranes and cristae. Sections were separately stained with affinity-purified polyclonal antibodies to these proteins as well as with three monoclonal anti-TSP antibodies. Antibody specificity was documented in radioimmunoassays, by immunofluorescent cross-blocking, and by staining of bands of appropriate mobility in Western blots of whole platelets. Bound antibody was visualized using a 5-nm colloidal gold-avidin conjugate. In resting cells, staining of virtually all alpha granules was observed for all four proteins. In contrast, consistent staining was absent from other organelles, including plasma membranes, mitochondria, and vacuolar structures that may represent the open canalicular system.  相似文献   
9.

Background

Patients with locally unresectable pancreatic cancer (AJCC stage III) have a median survival of 10?C14?months. The objective of this study was to evaluate outcome of initially unresectable patients who respond to multimodality therapy and undergo resection.

Methods

Using a prospectively collected database, patients were identified who were initially unresectable because of vascular invasion and had sufficient response to nonoperative treatment to undergo resection. Overall survival (OS) was compared with a matched group of patients who were initially resectable. Case matching was performed using a previously validated pancreatic cancer nomogram.

Results

A total of 36 patients with initial stage III disease were identified who underwent resection after treatment with either systemic therapy or chemoradiation. Initial unresectability was determined by operative exploration (n?=?15, 42%) or by cross-sectional imaging (n?=?21, 58%). Resection consisted of pancreaticoduodenectomy (n?=?31, 86%), distal pancreatectomy (n?=?4, 11%), and total pancreatectomy (n?=?1, 3%). Pathology revealed T3 lesions in 26 patients (73%), node positivity in 6 patients (16%), and a negative margin in 30 patients (83%). The median OS in this series was 25?months from resection and 30?months since treatment initiation. There was no difference in OS from time of resection between the initial stage III patients and those who presented with resectable disease (P?=?.35).

Conclusions

In this study, patients who were able to undergo resection following treatment of initial stage III pancreatic cancer experienced survival similar to those who were initially resectable. Resection is indicated in this highly select group of patients.  相似文献   
10.
BACKGROUND: The majority of patients with hepatocellular carcinoma (HCC) who undergo complete tumor resection subsequently develop tumor recurrence. The objectives of this study were to determine the risk factors for recurrence of HCC after hepatectomy and to examine the outcomes once tumor recurrence occurs. STUDY DESIGN: From February 1990 to May 2001 a total of 164 patients underwent liver resection for HCC at our institution and were prospectively followed. Time to recurrence and survival after recurrence were determined by Kaplan-Meier analysis. Patient, tumor, and treatment characteristics were tested for their prognostic significance by univariate and multivariate analysis using the logrank test and the Cox proportional hazards model, respectively. RESULTS: The median patient age was 64 years (range 21 to 87 years) and 106 patients (65%) were male. After a median followup of 26 months, 90 patients (55%) have developed recurrent cancer. Among them, 75 patients (83%) had tumor detectable in the liver, which was the only site of disease in 67 (74%). In all, 15 patients (20%) had extrahepatic disease (7 lung, 4 peritoneum, 2 pancreas, 1 bone, and 1 brain). The median time to recurrence was 24 months (range 1 to 274 months). Predictors of recurrence on univariate analysis were tumor size greater than 5 cm, more than one tumor, cirrhosis, vascular invasion (microscopic or macroscopic), and tumor satellites. On multivariate analysis only tumor size greater than 5 cm (p = 0.04) and vascular invasion (p = 0.01) predicted recurrence. The median survival after recurrence was 11 months (range 0 to 60 months). Of the 90 patients who developed tumor recurrence 49 (67%) were able to undergo additional ablative or surgical therapy (33 embolization, 9 ethanol injection, and 14 re-resection). On multivariate analysis vascular invasion in the original tumor predicted poor survival after recurrence (p = 0.009). CONCLUSIONS: The liver is the predominant site of first recurrence after resection of hepatocellular carcinoma, and once recurrence occurs survival is limited. The current study underscores the need for effective adjuvant therapy for patients with HCC treated with partial hepatectomy.  相似文献   
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